Piri Keşif Aracı

2

Statistical techniques for network security : modern statistically-based intrusion detection and protection

e-Kitap

Çevrimiçi

Kütüphane Kataloğu

Kaynak :

Karabük Üniversitesi

Demirbaş:

EK1981EABA

Kütüphane:

Karabük Üniversitesi Merkez Kütüphanesi

Yazar(lar) :

Yun. Wang

Konu :

Computer networks, Security measures, Computer security, Data mining and modeling, Data reduction techniques for network traffic, Data reliability, validity, and quality, Decision analysis in network security, Measure user behavior, Models network data for association and prediction, Network data characteristics, Network traffic and data, Statistical opportunity in network security, Statistical software for analyzing network data, Supervised learning techniques for network traffic classification, Unsupervised learning techniques for network traffic classification

Yun. Wang

Ek Bilgiler

Kopya: k.1
Künye Sınıflama Yer: Online
Fiziksel Tanım: electronic texts (xii, 461 p. : ill.) : : digital files.
Künye Sorumluları: Yun Wang.
Künye Yayın Yeri: Hershey, Pa.

Sınıflandırma :

Bilgisayar Bilimi %96

3

Review Article

Dergi Makalesi

Kaynak :

JSTOR

Dergi:

The American Statistician

Yayıncı:

American Statistical Association

Yazar(lar) :

Yun Wang

Konu :

Science & Mathematics, Statistics

Yun Wang

4

Immortality, and: The Visitation, and: Casanova: A Translation from Fellini

Dergi Makalesi

Kaynak :

JSTOR

Dergi:

Prairie Schooner

Yayıncı:

Project MUSE

Yazar(lar) :

Yun Wang

Yun Wang

Piri Tam Metin Bulucu

DOI : 10.1353/psg.2018.0022

5

The Pain Fish

Dergi Makalesi

Kaynak :

JSTOR

Dergi:

The Kenyon Review

Yayıncı:

Kenyon College

Yazar(lar) :

Yun Wang

Konu :

Humanities, Language & Literature

Yun Wang

6

Dark Energy Search with Supernovae

e-Kitap

Kaynak :

Internet Archive Books

Dergi:

Internet Archive

Yayıncı:

Internet Archive

Yazar(lar) :

Yun Wang

Yıl :

2004

Yun Wang

Özet Ek Bilgiler

To determine the nature of dark energy from observational data, it is important that we use model-independent and optimal methods. We should probe dark energy using its density (allowed to be a free function of cosmic time) instead of its equation of state. We should minimize gravitational lensing effect on supernovae by flux-averaging. We need to include complementary data (for example, from the Cosmic Microwave Background [CMB] and large scale structure [LSS]) in a consistent manner to help break the degeneracy between the dark energy density and the matter density fraction. We should push for ambitious future supernova surveys that can observe a large number of supernovae at the highest possible redshifts. I discuss these and other issues that will be important in our quest to unravel the mystery of the nature of dark energy. Current supernova, CMB, and LSS data already rule out dark energy models with dark energy densities that vary greatly with time; with the cosmological constant model providing an excellent fit to the data. A precise measurement of dark energy density as a free function of cosmic time will have a fundamental impact on particle physics and cosmology.

Sınıflandırma :

Fizik %100

Kozmoloji %94

7

Distance Measurements from Supernovae and Dark Energy Constraints

e-Kitap

Kaynak :

Internet Archive Books

Dergi:

Internet Archive

Yayıncı:

Internet Archive

Yazar(lar) :

Yun Wang

Yıl :

2009

Yun Wang

Özet

Constraints on dark energy from current observational data are sensitive to how distances are measured from Type Ia supernova (SN Ia) data. We find that flux-averaging of SNe Ia can be used to test the presence of unknown systematic uncertainties, and yield more robust distance measurements from SNe Ia. We have applied this approach to the nearby + SDSS +ESSENCE +SNLS +HST set of 288 SNe Ia, and the ``Constitution''of set 397 SNe Ia. Combining the SN Ia data with CMB data from WMAP five year observations, the Sloan Digital Sky Survey baryon acoustic oscillation measurements, the data of 69 gammay-ray bursts, and the Hubble constant measurement from the HST project SHOES, we measure the dark energy density function X(z)=\rho_X(z)/\rho_X(0) as a free function of redshift (assumed to be a constant at z>1 or z>1.5). Without flux-averaging of SNe Ia, the combined data using the ``Constitution'' set of SNe Ia seem to indicate a deviation from a cosmological constant at ~95% confidence level at 0< z <0.8; they are consistent with a cosmological constant at ~68% confidence level when SNe Ia are flux-averaged. The combined data using the nearby +SDSS +ESSENCE +SNLS +HST data set of SNe Ia are consistent with a cosmological constant at 68% confidence level with or without flux-averaging of SNe Ia, and give dark energy constraints that are significantly more stringent than that using the ``Constitution'' set of SNe Ia. Assuming a flat universe, dark energy is detected at >98% confidence level for z<= 0.75 using the combined data with 288 SNe Ia from nearby + SDSS+ ESSENCE +SNLS +HST, independent of the assumptions about X(z>1). We quantify dark energy constraints without assuming a flat universe using the dark energy Figure-of-Merit (FoM) for both $X(z)$ and a dark energy equation-of-state linear in the cosmic scale factor.

8

Observational approaches to understanding dark energy

e-Kitap

Kaynak :

Internet Archive Books

Dergi:

Internet Archive

Yayıncı:

Internet Archive

Yazar(lar) :

Yun Wang

Yıl :

2007

Yun Wang

Özet Ek Bilgiler

Illuminating the nature of dark energy is one of the most important challenges in cosmology today. In this review I discuss several promising observational approaches to understanding dark energy, in the context of the recommendations by the U.S. Dark Energy Task Force and the ESA-ESO Working Group on Fundamental Cosmology.

Sınıflandırma :

Fizik %95

Kozmoloji %51

Klasik ve Kuantum Yerçekimi %30

9

Model-Independent Measurements of Cosmic Expansion and Growth at z=0.57 Using the Anisotropic Clustering of CMASS Galaxies From the Sloan Digital Sky Survey Data Release 9

e-Kitap

Kaynak :

Internet Archive Books

Dergi:

arXiv.org

Yayıncı:

arXiv.org

Yazar(lar) :

Yun Wang

Yıl :

2014

Yun Wang

Özet Ek Bilgiler

We analyze the anisotropic two dimensional galaxy correlation function (2DCF) of the CMASS galaxy sample from the Sloan Digital Sky Survey Data Release 9 (DR9) of the Baryon Oscillation Spectroscopic Survey (BOSS) data. Modeling the 2DCF fully including nonlinear effects and redshift space distortions (RSD) in the scale range of 30 to 120 h^{-1}Mpc, we find H(0.57)r_s(z_d)/c=0.0444 +/- 0.0019, D_A(0.57)/r_s(z_d)=9.01 +/- 0.23, and f_g(0.57)\sigma_8(0.57)=0.474 +/- 0.075, where r_s(z_d) is the sound horizon at the drag epoch computed using a simple integral, and f_g(z) is the growth rate at redshift z, and \sigma_8(z) represents the matter power spectrum normalization on 8h^{-1}Mpc scale at z. We find that the scales larger than 120 h^{-1}Mpc are dominated by noise in the 2DCF analysis, and that the inclusion of scales 30-40 h^{-1}Mpc significantly tightens the RSD measurement. Our measurements are consistent with previous results using the same data, but have significantly better precision since we are using all the information from the 2DCF in the scale range of 30 to 120 h^{-1}Mpc. Our measurements have been marginalized over sufficiently wide priors for the relevant parameters; they can be combined with other data to probe dark energy and gravity.

DOI : urn:doi:10.1093/mnras/stu1374

Sınıflandırma :

Fizik %100

Kozmoloji %36

Gözlemler ve Teknikler %33

10

Polynomial Hybrid Inflation

e-Kitap

Kaynak :

Internet Archive Books

Dergi:

Internet Archive

Yayıncı:

Internet Archive

Yazar(lar) :

Yun Wang

Yıl :

1994

Yun Wang

Özet

We study a simple extension of Linde's hybrid inflation model, with the inflaton mass term replaced by the most general renormalizable potential for $\phi$. The unprocessed power spectrum of density perturbations can have two minima and one maximum, roughly corresponding to two steep regions separated by a somewhat flat region in $V(\phi)$. In the examples studied here, sufficient amount of inflation and normalization to COBE require a vacuum scale of $10^{16}$ GeV and a $\phi$ mass of $10^{13}$ GeV. Depending on the initial value of $\phi$, our model can give either less ($\sim n<1$) or more ($\sim n>1$) power on small scales compared to the scale-invariant spectrum ($n=1$), given the normalization to COBE.

11

Simple Analytical Methods for Computing the Gravity-Wave Contribution to the Cosmic Background Radiation Anisotropy

e-Kitap

Kaynak 1:

Internet Archive Books

Kaynak 2:

Internet Archive Books

Dergi:

Internet Archive

Yayıncı:

Internet Archive

Yazar(lar) :

Yun Wang

Yıl :

1995

Yun Wang

Yayıncı Web Siteleri

Özet Ek Bilgiler

We present two simple analytical methods for computing the gravity wave contribution to the cosmic background radiation (CBR) anisotropy in inflationary models; one method uses a time-dependent transfer function, the other method uses an approximate gravity-wave mode function which is a simple combination of the lowest order spherical Bessel functions. We compare the CBR anisotropy tensor multipole spectrum computed using our methods with the previous result of the highly accurate numerical method, the ``Boltzmann'' method. Our time-dependent transfer function is more accurate than the time-independent transfer function found by Turner, White, and Lidsey; however, we find that the transfer function method is only good for $l \la 120$. Using our approximate gravity-wave mode function, we obtain much better accuracy; the tensor multipole spectrum we find differs by less than 2\% for $l \la 50$, less than 10\% for $l \la 120$, and less than 20\% for $l \leq 300$ from the ``Boltzmann'' result. Our approximate graviton mode function should be quite useful in studying tensor perturbations from inflationary models.

Kaynak 1: https://archive.org/details/arxiv-astro-ph9501116 arayıcılığı görüntüle.
Kaynak 2: https://archive.org/details/arxiv-astro-ph9501116 arayıcılığı görüntüle.

Sınıflandırma :

Fizik %97

Klasik ve Kuantum Yerçekimi %100

12

S nü chu mo, zhu yi

e-Kitap

Kaynak :

Internet Archive Books

Dergi:

Beijing Shi : Zhongguo hua bao chu ban she

Yayıncı:

Beijing Shi : Zhongguo hua bao chu ban she

Yazar(lar) :

Yun Wang

Yıl :

2009

Yun Wang

Özet Ek Bilgiler

2 volumes ; 21 cm Fiction

Sayfa sayısı :362

Sınıflandırma :

Edebiyat %75

Kitabın Tarihi %38

13

Flux-averaging Analysis of Type Ia Supernova Data

e-Kitap

Kaynak :

Internet Archive Books

Dergi:

Internet Archive

Yayıncı:

Internet Archive

Yazar(lar) :

Yun Wang

Yıl :

2000

Yun Wang

Özet Ek Bilgiler

Because of flux conservation, flux-averaging {\it justifies} the use of the distance-redshift relation for a smooth universe in the analysis of type Ia supernova (SN Ia) data. We have combined the SN Ia data from the High-$z$ SN Search and the Supernova Cosmology Project, and binned the combined data by flux-averaging in redshift intervals of $\Delta z=0.05$ and $\Delta z=0.1$. We find that the unbinned data yield a Hubble constant of $H_0=65\pm 1 $km$ $s$^{-1} $Mpc$^{-1}$ (statistical error only), a matter density fraction of $\Omega_m=0.7\pm0.4$, and a vacuum energy density fraction of $\Omega_{\Lambda}=1.2\pm0.5$. The binned data for $\Delta z=0.1$ yield $H_0=65\pm 1 $km$ $s$^{-1} $Mpc$^{-1}$ (statistical error only), $\Omega_m=0.3\pm0.6$, and $\Omega_{\Lambda}=0.7\pm0.7$. Our results are not sensitive to the redshift bin size. Flux-averaging leads to less biased estimates of the cosmological parameters by reducing the bias due to systematic effects such as weak lensing. Comparison of the data of 18 SNe Ia published by both groups yields a mean SN Ia peak absolute magnitude of $M_B=-19.33\pm 0.25$. The internal dispersion of each data set is about 0.20 magnitude in the {\it calibrated} SN Ia peak absolute magnitudes. The difference in analysis techniques introduces an additional uncertainty of about 0.15 magnitude. If the SNe Ia peak absolute luminosity changes with redshift due to evolution, our ability to measure the cosmological parameters from SN Ia data will be significantly diminished.

Sınıflandırma :

Fizik %100

Kozmoloji %58

Gözlemler ve Teknikler %37

14

Clarifying Forecasts of Dark Energy Constraints from Baryon Acoustic Oscillations

e-Kitap

Kaynak :

Internet Archive Books

Dergi:

Internet Archive

Yayıncı:

Internet Archive

Yazar(lar) :

Yun Wang

Yıl :

2009

Yun Wang

Özet

The measurement of baryon acoustic oscillations (BAO) from a galaxy redshift survey provides one of the most promising methods for probing dark energy. In this paper, we clarify the assumptions that go into the forecasts of dark energy constraints from BAO. We show that assuming a constant nP_{0.2}/G^2(z) (where P_{0.2} is the real space galaxy power spectrum at k=0.2h/Mpc and redshift z) gives a good approximation of the observed galaxy number density expected from a realistic flux-limited galaxy redshift survey. We find that assuming nP_{0.2}/G^2(z)=10 gives very similar dark energy constraints to assuming nP_{0.2}=3, but the latter corresponds to a galaxy number density larger by ~70% at z=2. We show how the Figure-of-Merit (FoM) for constraining dark energy depends on the assumed galaxy number density, redshift accuracy, redshift range, survey area, and the systematic errors due to calibration and uncertainties in the theory of nonlinear evolution and galaxy biasing. We find that an additive systematic noise of up to 0.4-0.5% per dz=0.1 redshift slice does not lead to significant decrease in the BAO FoM.

15

Figure of Merit for Dark Energy Constraints from Current Observational Data

e-Kitap

Kaynak :

Internet Archive Books

Dergi:

Internet Archive

Yayıncı:

Internet Archive

Yazar(lar) :

Yun Wang

Yıl :

2008

Yun Wang

Özet Ek Bilgiler

Choosing the appropriate figure of merit (FoM) for dark energy (DE) constraints is key in comparing different DE experiments. Here we show that for a set of DE parameters {f_i}, it is most intuitive to define FoM = 1/\sqrt{Cov(f1,f2,f3,...)}, where Cov(f1,f2,f3,...) is the covariance matrix of {f_i}. The {f_i} should be minimally correlated. We demonstrate two useful choices of {f_i} using 182 SNe Ia (compiled by Riess et al. 2007), [R(z_*), l_a(z_*), \Omega_b h^2] from the five year Wilkinson Microwave Anisotropy Probe (WMAP) observations, and SDSS measurement of the baryon acoustic oscillation (BAO) scale, assuming the HST prior of H_0=72+/-8 km/s Mpc^{-1} and without assuming spatial flatness. We find that the correlation of (w_0,w_{0.5}) [w_0=w_X(z=0), w_{0.5}=w_X(z=0.5), w_X(a) = 3w_{0.5}-2w_0+3(w_0-w_{0.5})a] is significantly smaller than that of (w_0,w_a) [w_X(a)=w_0+(1-a)w_a]. In order to obtain model-independent constraints on DE, we parametrize the DE density function X(z)=\rho_X(z)/\rho_X(0) as a free function with X_{0.5}, X_{1.0}, and X_{1.5} [values of X(z) at z=0.5, 1.0, and 1.5] as free parameters estimated from data. If one assumes a linear DE equation of state, current data are consistent with a cosmological constant at 68% C.L. If one assumes X(z) to be a free function parametrized by (X_{0.5}, X_{1.0}, X_{1.5}), current data deviate from a cosmological constant at z=1 at 68% C.L., but are consistent with a cosmological constant at 95% C.L.. Future DE experiments will allow us to dramatically increase the FoM of constraints on (w_0,w_{0.5}) and of (X_{0.5}, X_{1.0}, X_{1.5}). This will significantly shrink the DE parameter space to enable the discovery of DE evolution, or the conclusive evidence for a cosmological constant.

Sınıflandırma :

Fizik %100

Kozmoloji %78

16

Analytical Modeling of the Weak Lensing of Standard Candles I. Empirical Fitting of Numerical Simulation Results

e-Kitap

Kaynak :

Internet Archive Books

Dergi:

Internet Archive

Yayıncı:

Internet Archive

Yazar(lar) :

Yun Wang

Yıl :

1999

Yun Wang

Özet Ek Bilgiler

Weak lensing leads to the non-Gaussian magnification distribution of standard candles at given redshift $z$, $p(\mu|z)$. In this paper, we give accurate and simple empirical fitting formulae of the weak lensing numerical simulation results with the generalized Dyer-Roeder prescription. The smoothness parameter $\tilde{\alpha}$ essentially represents the amount of matter that can cause magnification of a given source. Since matter distribution in our universe is inhomogeneous, we can think of our universe as a mosaic of cones centered on the observer, each with a different value of $\tilde{\alpha}$. We define the {\it direction dependent} smoothness parameter $\tilde{\alpha}$ via the Dyer-Roeder equation; there is a unique mapping between $\tilde{\alpha}$ and the magnification of a source. We find that the distribution of $\tilde{\alpha}$ at given $z$, $p(\tilde{\alpha}|z)$, is well described by a modified Gaussian distribution. For the same matter distribution, i.e., the same $p(\tilde{\alpha}|z)$, different values of $\Omega_m$ and $\Omega_{\Lambda}$ can lead to very different magnification distributions. Our formulae can be conveniently used to calculate the weak lensing effects for observed Type Ia supernovae at arbitrary redshifts.

Sınıflandırma :

Fizik %100

Klasik ve Kuantum Yerçekimi %57

Gözlemler ve Teknikler %24

17

A Model-Independent Photometric Redshift Estimator for Type Ia Supernovae

e-Kitap

Kaynak :

Internet Archive Books

Dergi:

Internet Archive

Yayıncı:

Internet Archive

Yazar(lar) :

Yun Wang

Yıl :

2006

Yun Wang

Özet Ek Bilgiler

The use of type Ia supernovae (SNe Ia) as cosmological standard candles is fundamental in modern observational cosmology. In this letter, we derive a simple empirical photometric redshift estimator for SNe Ia using a training set of SNe Ia with multiband ($griz$) light-curves and spectroscopic redshifts obtained by the Supernova Legacy Survey (SNLS). This estimator is analytical and model-independent; it does not use spectral templates. We use all the available SNe Ia from SNLS with near maximum photometry in $griz$ (a total of 40 SNe Ia) to train and test our photometric redshift estimator. The difference between the estimated redshifts $z_{phot}$ and the spectroscopic redshifts $z_{spec}$, $(z_{phot}-z_{spec})/(1+z_{spec})$, has rms dispersions of 0.031 for 20 SNe Ia used in the training set, and 0.050 for 20 SNe Ia not used in the training set. The dispersion is of the same order of magnitude as the flux uncertainties at peak brightness for the SNe Ia. There are no outlyers. This photometric redshift estimator should significantly enhance the ability of observers to accurately target high redshift SNe Ia for spectroscopy in ongoing surveys. It will also dramatically boost the cosmological impact of very large future supernova surveys, such as those planned for Advanced Liquid-mirror Probe for Astrophysics, Cosmology and Asteroids (ALPACA), and the Large Synoptic Survey Telescope (LSST).

Sınıflandırma :

Fizik %100

Kozmoloji %85

18

Observational signatures of the weak lensing magnification of supernovae

e-Kitap

Kaynak :

Internet Archive Books

Dergi:

Internet Archive

Yayıncı:

Internet Archive

Yazar(lar) :

Yun Wang

Yıl :

2005

Yun Wang

Özet Ek Bilgiler

Due to the deflection of light by density fluctuations along the line of sight, weak lensing is an unavoidable systematic uncertainty in the use of type Ia supernovae (SNe Ia) as cosmological distance indicators. We derive the expected weak lensing signatures of SNe Ia by convolving the intrinsic distribution in SN Ia peak luminosity with magnification distributions of point sources. We analyze current SN Ia data, and find marginal evidence for weak lensing effects. The statistics is poor because of the small number of observed SNe Ia. Future observational data will allow unambiguous detection of the weak lensing effect of SNe Ia. The observational signatures of weak lensing of SNe Ia that we have derived provide useful templates with which future data can be compared.

Sınıflandırma :

Fizik %100

Astrofizik ve Kozmoloji %88

19

Hui fei de jiao shi

e-Kitap

Kaynak :

Internet Archive Books

Dergi:

Beijing : Beijing shao nian er tong chu ban she

Yayıncı:

Beijing : Beijing shao nian er tong chu ban she

Yazar(lar) :

Yun Wang

Yıl :

2008

Yun Wang

Özet Ek Bilgiler

2, 150 pages

Cilt :2
Sayfa sayısı :166

Sınıflandırma :

Edebiyat %84

Asya Edebiyatı %100

20

Model-Independent Distance Measurements from Gamma-Ray Bursts and Constraints on Dark Energy

e-Kitap

Kaynak :

Internet Archive Books

Dergi:

Internet Archive

Yayıncı:

Internet Archive

Yazar(lar) :

Yun Wang

Yıl :

2008

Yun Wang

Özet Ek Bilgiler

Gamma-Ray Bursts (GRB) are the most energetic events in the Universe, and provide a complementary probe of dark energy by allowing the measurement of cosmic expansion history that extends to redshifts greater than 6. Unlike Type Ia supernovae (SNe Ia), GRBs must be calibrated for each cosmological model considered, because of the lack of a nearby sample of GRBs for model-independent calibration. For a flat Universe with a cosmological constant, we find Omega_m=0.25^{+0.12}_{-0.11} from 69 GRBs alone. We show that the current GRB data can be summarized by a set of model-independent distance measurements, with negligible loss of information. We constrain a dark energy equation of state linear in the cosmic scale factor using these distance measurements from GRBs, together with the "Union" compilation of SNe Ia, WMAP five year observations, and the SDSS baryon acoustic oscillation scale measurement. We find that a cosmological constant is consistent with current data at 68% confidence level for a flat Universe. Our results provide a simple and robust method to incorporate GRB data in a joint analysis of cosmological data to constrain dark energy.

Sınıflandırma :

Fizik %100

Kozmoloji %83

21

Mass and radius of cosmic balloons

e-Kitap

Kaynak :

Internet Archive Books

Dergi:

Internet Archive

Yayıncı:

Internet Archive

Yazar(lar) :

Yun Wang

Yıl :

1994

Yun Wang

Özet Ek Bilgiler

This revised version uses Gauss-Codazzi equations to derive the exact mass and radius relations. The results remain qualitatively the same.

Sınıflandırma :

Fizik %79

Klasik ve Kuantum Yerçekimi %23

22

Shuo wen shi li : 20 juan

e-Kitap

Kaynak :

Internet Archive Books

Dergi:

[s.l.] : Guo xue zheng li she

Yayıncı:

[s.l.] : Guo xue zheng li she

Yazar(lar) :

Yun Wang

Yıl :

1936

Yun Wang

Özet Ek Bilgiler

In colophon: Ying yin Shuo wen shi li 11

Sayfa sayısı :980

Sınıflandırma :

Dilbilim %61

Çince %100

Ekonomi %37

Asya Ekonomisi %100

23

Differentiating dark energy and modified gravity with galaxy redshift surveys

e-Kitap

Kaynak :

Internet Archive Books

Dergi:

Internet Archive

Yayıncı:

Internet Archive

Yazar(lar) :

Yun Wang

Yıl :

2008

Yun Wang

Özet Ek Bilgiler

The observed cosmic acceleration today could be due to an unknown energy component (dark energy), or a modification to general relativity (modified gravity). If dark energy models and modified gravity models are required to predict the same cosmic expansion history H(z), they will predict different growth rate for cosmic large scale structure, f_g(z)=d\ln \delta/d\ln a (\delta=(\rho_m-\bar{\rho_m})/\bar{\rho_m}), a is the cosmic scale factor). If gravity is not modified, the measured H(z) leads to a unique prediction for f_g(z), f_g^H(z). Comparing f_g^H(z) with the measured f_g(z) provides a transparent and straightforward test of gravity. We show that a simple \chi^2 test provides a general figure-of-merit for our ability to distinguish between dark energy and modified gravity given the measured H(z) and f_g(z). We study a magnitude-limited NIR galaxy redshift survey covering >10,000 (deg)^2 and the redshift range of 0.5

Sınıflandırma :

Fizik %100

Klasik ve Kuantum Yerçekimi %77

Kozmoloji %20

24

The Statistics of Nearly On-Axis Gravitational Lensing Events

e-Kitap

Kaynak :

Internet Archive Books

Dergi:

Internet Archive

Yayıncı:

Internet Archive

Yazar(lar) :

Yun Wang

Yıl :

1995

Yun Wang

Özet Ek Bilgiler

A small volume of space, nearly on-axis behind a gravitational lens with respect to a given source, will receive a greatly increased radiation flux. In the idealized case of a point mass lens acting on a point source in complete isolation, the volume will approach zero only as the flux tends to infinity; in fact, the volume weighted rms flux is divergent. In realistic cases, finite source size and the effects of other gravitational deflections (i.e., non-zero shear) limit the maximum flux and considerably complicate the physics, but very large fluxes are still produced in small volumes. We consider the physics and statistics of these Extreme Gravitational Lensing Events (EGLE) and present an initial examination of their possible astrophysical effects for various known and putative populations of lensing objects and sources, with particular attention to the case in which finite source size is important but shear is not.

Sınıflandırma :

Fizik %100

Klasik ve Kuantum Yerçekimi %81

25

Self-lensing of a Singular Isothermal Sphere

e-Kitap

Kaynak :

Internet Archive Books

Dergi:

Internet Archive

Yayıncı:

Internet Archive

Yazar(lar) :

Yun Wang

Yıl :

2000

Yun Wang

Özet Ek Bilgiler

Many astrophysical systems can be approximated as isothermal spheres. In an isothermal sphere, the ``foreground'' objects can act as lenses on ``background'' objects in the same distribution. We study gravitational lensing by a singular isothermal sphere analytically. Our results may have interesting applications.

Sınıflandırma :

Fizik %96

Klasik ve Kuantum Yerçekimi %62

26

Dark Energy Constraints from Baryon Acoustic Oscillations

e-Kitap

Kaynak :

Internet Archive Books

Dergi:

Internet Archive

Yayıncı:

Internet Archive

Yazar(lar) :

Yun Wang

Yıl :

2006

Yun Wang

Özet

Baryon acoustic oscillations (BAO) in the galaxy power spectrum allows us to extract the scale of the comoving sound horizon at recombination, a cosmological standard ruler accurately determined by the cosmic microwave background anisotropy data. We examine various issues important in the use of BAO to probe dark energy. We find that assuming a flat universe, and priors on Omega_m, Omega_m h^2, and Omega_b h^2 as expected from the Planck mission, the constraints on dark energy parameters (w_0,w') scale much less steeply with survey area than (area)^{-1/2} for a given redshift range. The constraints on the dark energy density rho_X(z), however, do scale roughly with (area)^{-1/2} due to the strong correlation between H(z) and Omega_m (which reduces the effect of priors on Omega_m). Dark energy constraints from BAO are very sensitive to the assumed linear scale of matter clustering and the redshift accuracy of the survey. For a BAO survey with 0.5<= z <= 2, sigma(R)=0.4 (corresponding to k_{max}(z=0)=0.086 h Mpc^{-1}), and sigma_z/(1+z)=0.001, (sigma_{w_0},sigma_{w'})=(0.115, 0.183) and (0.069, 0.104) for survey areas of 1000 (deg)^2 and 10000 (deg)^2 respectively. We find that it is critical to minimize the bias in the scale estimates in order to derive reliable dark energy constraints. For a 1000 (10000) square degree BAO survey, a 1-sigma bias in ln H(z) leads to a 2-sigma (3-sigma) bias in w'. The bias in w' due to the same scale bias from ln D_A(z) is slightly smaller and opposite in sign. The results from this paper will be useful in assessing different proposed BAO surveys and guiding the design of optimal dark energy detection strategies.

27

Statistical techniques for network security : modern statistically-based intrusion detection and protection

e-Kitap

çevrimiçi

Kütüphane Kataloğu

Kaynak :

Amasya Üniversitesi

Yer Numarası:

Online

Demirbaş:

EK95B069E0

Kütüphane:

Amasya Üniversitesi Merkez Kütüphanesi

Yazar(lar) :

Yun. Wang

Konu :

Network data characteristics, Network traffic and data, Statistical software for analyzing network data, Statistical opportunity in network security, Data reduction techniques for network traffic, Decision analysis in network security, Measure user behavior, Security measures, Data reliability, validity, and quality, Computer networks, Computer security, Data mining and modeling, Models network data for association and prediction, Supervised learning techniques for network traffic classification, Unsupervised learning techniques for network traffic classification

Yıl :

2009

Yun. Wang

Özet

Eser Adı
Statistical techniques for network security : modern statistically-based intrusion detection and protection

Yazar
Wang, Yun.

Yayın Tarihi
c2009

Yayınlayan
IGI Global (701 E. Chocolate Avenue Hershey Pennsylvania 17033 USA)

Yayın Yeri
Hershey, Pa.

Konu
Computer networksSecurity measures.Computer security.Data mining and modelingData reduction techniques for network trafficData reliability, validity, and qualityDecision analysis in network securityMeasure user behaviorModels network data for association and predictionNetwork data characteristicsNetwork traffic and dataStatistical opportunity in network securityStatistical software for analyzing network dataSupervised learning techniques for network traffic classificationUnsupervised learning techniques for network traffic classification

Dil
İngilizce

ISBN
9781599047102 (PDF) 1599047101 (PDF) 9781599047089 (hardcover) 159904708X (hardcover) 9781616925048 (softcover)

Notlar
Includes bibliographical references and index.1. Statistical opportunities, roles, and challenges in network security -- 2. Statistical analysis software -- 3. Network traffic and data -- 4. Network data characteristics -- 5. Exploring network data -- 6. Data reduction -- 7. Models network data for association and prediction -- 8. Measuring user behavior -- 9. Classification based on supervised learning -- 10. Classification based on unsupervised learning -- 11. Decision analysis in network security -- 12. Evaluation.Restricted to subscribers or individual electronic text purchasers.

Fiziksel Nitelik
electronic texts (xii, 461 p. : ill.) : : digital files.

Yayın Geliş Tarihi
05.12.2019

Demirbaş Numarası
EK95B069E0

Yer Bilgisi
Online

Kütüphane
Amasya Üniversitesi Merkez Kütüphanesi

28

Statistical techniques for network security : modern statistically-based intrusion detection and protection

e-Kitap

çevrimiçi

Kütüphane Kataloğu

Kaynak :

İskenderun Teknik Üniversitesi

Yer Numarası:

Online

Demirbaş:

EKE5AE0F8F

Kütüphane:

İskenderun Teknik Üniversitesi Merkez Kütüphanesi

Yazar(lar) :

Yun. Wang

Konu :

Network data characteristics, Network traffic and data, Statistical software for analyzing network data, Statistical opportunity in network security, Data reduction techniques for network traffic, Decision analysis in network security, Measure user behavior, Security measures, Data reliability, validity, and quality, Computer networks, Computer security, Data mining and modeling, Models network data for association and prediction, Supervised learning techniques for network traffic classification, Unsupervised learning techniques for network traffic classification

Yıl :

2009

Yun. Wang

Özet

Eser Adı
Statistical techniques for network security : modern statistically-based intrusion detection and protection

Yazar
Wang, Yun.

Sorumlular
Yun Wang.

Yayın Tarihi
c2009.

Yayınlayan
IGI Global (701 E. Chocolate Avenue, Hershey, Pennsylvania, 17033, USA),

Yayın Yeri
Hershey, Pa.

Konu
Computer networksSecurity measures.Computer security.Data mining and modelingData reduction techniques for network trafficData reliability, validity, and qualityDecision analysis in network securityMeasure user behaviorModels network data for association and predictionNetwork data characteristicsNetwork traffic and dataStatistical opportunity in network securityStatistical software for analyzing network dataSupervised learning techniques for network traffic classificationUnsupervised learning techniques for network traffic classification

Dil
İngilizce

ISBN
9781599047102 (PDF) 1599047101 (PDF) 9781599047089 (hardcover) 159904708X (hardcover) 9781616925048 (softcover)

Notlar
Includes bibliographical references and index.1. Statistical opportunities, roles, and challenges in network security -- 2. Statistical analysis software -- 3. Network traffic and data -- 4. Network data characteristics -- 5. Exploring network data -- 6. Data reduction -- 7. Models network data for association and prediction -- 8. Measuring user behavior -- 9. Classification based on supervised learning -- 10. Classification based on unsupervised learning -- 11. Decision analysis in network security -- 12. Evaluation.Restricted to subscribers or individual electronic text purchasers.

Fiziksel Nitelik
electronic texts (xii, 461 p. : ill.) : digital files.

Yayın Geliş Tarihi
18.06.2020

Demirbaş Numarası
EKE5AE0F8F

Yer Bilgisi
Online

Kütüphane
İskenderun Teknik Üniversitesi Merkez Kütüphanesi

29

Modeling and performance analysis of queueing systems.

Tez

Kaynak :

Canada Theses

Dergi:

Ottawa :National Library of Canada = Bibliothèque nationale du Canada,1993.

Yayıncı:

Ottawa :National Library of Canada = Bibliothèque nationale du Canada,1993.

Yazar(lar) :

Yun Wang

Yıl :

1993

Yun Wang

Özet Ek Bilgiler