Why Does a Kronecker Model Result in Misleading Capacity Estimates?

Many recent works that study the performance of multi-input multi-output (MIMO) systems in practice assume a Kronecker model where the variances of the channel entries, upon decomposition on to the transmit and the receive eigen-bases, admit a separable form. Measurement campaigns, however, show that the Kronecker model results in poor estimates for capacity. Motivated by these observations, a channel model that does not impose a separable structure has been recently proposed and shown to fit the capacity of measured channels better. In this work, we show that this recently proposed modeling framework can be viewed as a natural consequence of channel decomposition on to its canonical coordinates, the transmit and/or the receive eigen-bases. Using tools from random matrix theory, we then establish the theoretical basis behind the Kronecker mismatch at the low- and the high-SNR extremes: 1) Sparsity of the dominant statistical degrees of freedom (DoF) in the true channel at the low-SNR extreme, and 2) Non-regularity of the sparsity structure (disparities in the distribution of the DoF across the rows and the columns) at the high-SNR extreme.Comment: 39 pages, 5 figures, under review with IEEE Trans. Inform. Theor

Exhaustive Search-based Model for Hybrid Sensor Network

A new model for a cluster of hybrid sensors network with multi sub-clusters is proposed. The model is in particular relevant to the early warning system in a large scale monitoring system in, for example, a nuclear power plant. It mainly addresses to a safety critical system which requires real-time processes with high accuracy. The mathematical model is based on the extended conventional search algorithm with certain interactions among the nearest neighborhood of sensors. It is argued that the model could realize a highly accurate decision support system with less number of parameters. A case of one dimensional interaction function is discussed, and a simple algorithm for the model is also given.Comment: 6 pages, Proceeding of the International Conference on Intelligent & Advanced Systems 2012 pp. 557-56

Optical Photometry and Spectroscopy of the Suspected Cool Algol AV Delphini: Determination of the Physical Properties

We present new spectroscopic and BVRI photometric observations of the double-lined eclipsing binary AV Del ( period = 3:85 days) conducted over six observing seasons. A detailed radial velocity and light-curve analysis of the optical data shows the system to be most likely semidetached, with the less massive and cooler star filling its Roche lobe. The system is probably a member of the rare class of ‘‘cool Algol’’ systems, which are distinguished from the ‘‘classical’’ Algol systems in that the mass-gaining component is also a late-type star rather than a B- or A-type star. By combining the spectroscopic and photometric analyses, we derive accurate absolute masses for the components of M1 = 1.453 + 0.028 M and M2 = 0.705 + 0.014 M and radii of R1 = 2.632 + 0.030 R and R2 = 4.233 + 0.060 R, as well as effective temperatures of 6000 + 200 and 4275 + 150 K for the primary and secondary, respectively. There are no obvious signs of activity (spottedness) in the optical light curve of the binary

Non-Invasive Induction Link Model for Implantable Biomedical Microsystems: Pacemaker to Monitor Arrhythmic Patients in Body Area Networks

In this paper, a non-invasive inductive link model for an Implantable Biomedical Microsystems (IBMs) such as, a pacemaker to monitor Arrhythmic Patients (APs) in Body Area Networks (BANs) is proposed. The model acts as a driving source to keep the batteries charged, inside a device called, pacemaker. The device monitors any drift from natural human heart beats, a condition of arrythmia and also in turn, produces electrical pulses that create forced rhythms that, matches with the original normal heart rhythms. It constantly sends a medical report to the health center to keep the medical personnel aware of the patient's conditions and let them handle any critical condition, before it actually happens. Two equivalent models are compared by carrying the simulations, based on the parameters of voltage gain and link efficiency. Results depict that the series tuned primary and parallel tuned secondary circuit achieves the best results for both the parameters, keeping in view the constraint of coupling co-efficient (k), which should be less than a value \emph{0.45} as, desirable for the safety of body tissues.Comment: IEEE 8th International Conference on Broadband and Wireless Computing, Communication and Applications (BWCCA'13), Compiegne, Franc

Topological superconductivity of spin-3/2 carriers in a three-dimensional doped Luttinger semimetal

We investigate topological Cooper pairing, including gapless Weyl and fully gapped class DIII superconductivity, in a three-dimensional doped Luttinger semimetal. The latter describes effective spin-3/2 carriers near a quadratic band touching and captures the normal-state properties of the 227 pyrochlore iridates and half-Heusler alloys. Electron-electron interactions may favor non-$s$-wave pairing in such systems, including even-parity $d$-wave pairing. We argue that the lowest energy $d$-wave pairings are always of complex (e.g., $d + i d$) type, with nodal Weyl quasiparticles. This implies $\varrho(E) \sim |E|^2$ scaling of the density of states (DoS) at low energies in the clean limit, or $\varrho(E) \sim |E|$ over a wide critical region in the presence of disorder. The latter is consistent with the $T$-dependence of the penetration depth in the half-Heusler compound YPtBi. We enumerate routes for experimental verification, including specific heat, thermal conductivity, NMR relaxation time, and topological Fermi arcs. Nucleation of any $d$-wave pairing also causes a small lattice distortion and induces an $s$-wave component; this gives a route to strain-engineer exotic $s+d$ pairings. We also consider odd-parity, fully gapped $p$-wave superconductivity. For hole doping, a gapless Majorana fluid with cubic dispersion appears at the surface. We invent a generalized surface model with $\nu$-fold dispersion to simulate a bulk with winding number $\nu$. Using exact diagonalization, we show that disorder drives the surface into a critically delocalized phase, with universal DoS and multifractal scaling consistent with the conformal field theory (CFT) SO($n$)${}_\nu$, where $n \rightarrow 0$ counts replicas. This is contrary to the naive expectation of a surface thermal metal, and implies that the topology tunes the surface renormalization group to the CFT in the presence of disorder.Comment: Published Version in PRB (Editors' Suggestion): 49 Pages, 17 Figures, 3 Table

Analisis dan Evaluasi Peringkat Website Perguruan Tinggi Terbaik di Indonesia Menggunakan Teknik Search Engine Optimization (SEO)

Teknik Search Engine Optimization (SEO) merupakan salah satu teknik yang wajib diterapkan pada sebuah website, hal itu dianggap penting karena setiap website memerlukan kunjungan agar trafik website meningkat. Website universitas seharusnya dapat menerapkan SEO dengan baik agar website tersebut banyak pengunjung. Penerapan metode SEO tentunya tidak hanya dilakukan submit melalui webmaster mesin pencari, namun pada sebuah website juga harus diterapkan kata kunci yang berkaitan dengan isi konten website tersebut, karena dengan adanya kata kunci maka akan secara otomatis menarik para pengunjung ke website universitas berdasakan frasa kata kunci yang mereka ketik di mesin pencari. Dari hasil analisis yang telah dilakukan oleh penulis maka dapat diambil kesimpulan bahwa website dengan penerapan SEO yang tepat maka akan dapat meningkatkan trafik pengunjung, para pengguna yang mengunjungi website tentunya bukan hanya mencari informasi saja, namun mereka juga melakukan pencarian berdasarkan kebutuhan mereka seperti informasi penerimaan mahasiswa baru, pencarian repository, jurnal maupun info lain yang dibutuhka