Efficient networks for quantum factoring

We consider how to optimize memory use and computation time in operating a quantum computer. In particular, we estimate the number of memory quantum bits (qubits) and the number of operations required to perform factorization, using the algorithm suggested by Shor [in Proceedings of the 35th Annual Symposium on Foundations of Computer Science, edited by S. Goldwasser (IEEE Computer Society, Los Alamitos, CA, 1994), p. 124]. A K-bit number can be factored in time of order K3 using a machine capable of storing 5K+1 qubits. Evaluation of the modular exponential function (the bottleneck of Shor’s algorithm) could be achieved with about 72K3 elementary quantum gates; implementation using a linear ion trap would require about 396K3 laser pulses. A proof-of-principle demonstration of quantum factoring (factorization of 15) could be performed with only 6 trapped ions and 38 laser pulses. Though the ion trap may never be a useful computer, it will be a powerful device for exploring experimentally the properties of entangled quantum states

The Block Point Process Model for Continuous-Time Event-Based Dynamic Networks

We consider the problem of analyzing timestamped relational events between a set of entities, such as messages between users of an on-line social network. Such data are often analyzed using static or discrete-time network models, which discard a significant amount of information by aggregating events over time to form network snapshots. In this paper, we introduce a block point process model (BPPM) for continuous-time event-based dynamic networks. The BPPM is inspired by the well-known stochastic block model (SBM) for static networks. We show that networks generated by the BPPM follow an SBM in the limit of a growing number of nodes. We use this property to develop principled and efficient local search and variational inference procedures initialized by regularized spectral clustering. We fit BPPMs with exponential Hawkes processes to analyze several real network data sets, including a Facebook wall post network with over 3,500 nodes and 130,000 events.Comment: To appear at The Web Conference 201

Leveraging Friendship Networks for Dynamic Link Prediction in Social Interaction Networks

On-line social networks (OSNs) often contain many different types of relationships between users. When studying the structure of OSNs such as Facebook, two of the most commonly studied networks are friendship and interaction networks. The link prediction problem in friendship networks has been heavily studied. There has also been prior work on link prediction in interaction networks, independent of friendship networks. In this paper, we study the predictive power of combining friendship and interaction networks. We hypothesize that, by leveraging friendship networks, we can improve the accuracy of link prediction in interaction networks. We augment several interaction link prediction algorithms to incorporate friendships and predicted friendships. From experiments on Facebook data, we find that incorporating friendships into interaction link prediction algorithms results in higher accuracy, but incorporating predicted friendships does not when compared to incorporating current friendships.Comment: To appear in ICWSM 2018. This version corrects some minor errors in Table 1. MATLAB code available at https://github.com/IdeasLabUT/Friendship-Interaction-Predictio

Non-uniform transmission line ultra-wideband wilkinson power divider

We propose a technique with clear guidelines to design a compact planar Wilkinson power divider (WPD) for ultra-wideband (UWB) applications. The design procedure is accomplished by replacing the uniform transmission lines in each arm of the conventional power divider with varying-impedance profiles governed by a truncated Fourier series. Such non-uniform transmission lines (NTLs) are obtained through the even mode analysis, whereas three isolation resistors are optimized in the odd mode circuit to achieve proper isolation and output ports matching over the frequency range of interest. For verification purposes, an in-phase equal split WPD is designed, simulated, and measured. Simulation and measurement results show that the input and output ports matching as well as the isolation are below -10 dB, whereas the transmission parameters are in the range of (-3:2 dB, -4:2 dB) across the 3.1 GHz-10.6 GHz band

Elastic brain image registration using mutual information

Image Registration is the determination of a geometrical transformation that aligns points in one image of an object with corresponding points in another image. The source image is geometrically transformed to match the target image. The geometric transformation can be rigid or non-rigid. Rigid transformations preserve straight lines and angles between straight lines. The basic rigid transformations are rotation, scaling and translation. In this thesis non-rigid registration using B-splines is the method being used to take into account the elastic change in the brain structure. The B-spline equation is a type of curved transformation that does not preserve the straightness of lines, as is the case with rigid transformation. A similarity measure is based on similar pixel values in the image pairs. It is used as a cost function to measure the similarity between the source and target image. Mutual information is a similarity measure based on the probability density function. Optimization of both rigid and non-rigid registration techniques is performed to obtain the registration parameters that define the best geometrical transformation. The parameters are optimized based on the mutual information. Neurosurgery is an application of image registration and requires accurate surgical planning and guidance because of complex and delicate structures in the brain. Over the course of the surgery, the brain changes its shape in reaction to mechanical and physiological changes associated with the surgery such as loss of cerebrospinal fluid and gravity forces

Selection of Capacitors for the Self Excited Slip ring Induction Generator with External Rotor Capacitance

The self regulating feature of a Self Excited Induction Generator (SEIG) by connecting additional capacitors is examined with the slip ring induction generator. The system consisting of external rotor capacitors at rotor has been analyzed. A methodology has been explained to choose appropriate set of values of these rotor capacitors for desired voltage regulation. Based on the steady-state equivalent circuit model, consideration of the circuit conductances yields a 7th-degree polynomial in the frequency. The polynomial can be solved for real roots, which enables the value of C, to be calculated. Critical values of load impedance and speed, below which the machine fails to self-excite irrespective of the capacitance used, are found to exist. Closed form solutions for C are derived for different loads. Using the Same numerical approach, an iterative procedure is also developed for predicting the capacitance required for maintaining the terminal voltage at a preset value when the generator is supplying load. Results of a detailed investigation on a conventional 3.5 kW induction motor operated as a SEIG are presented to illustrate the effectiveness of the proposed method. Close agreement between predicted and test results has been observed thereby establishing the validity of the analysis carried Keywords: capacitance requirements, self-excitation, slip ring induction generator, external rotor capacitanc

Hysteroscopy to identify retained placental tissue and excision in secondary post-partum haemorrhage

Background: Most cases of secondary postpartum haemorrhage (PPH) are due to retained placental products (RPP). This study had a crop of five cases of secondary PPH, referral cases, during a period of six months during 2006. Four cases were following a caesarean delivery and in one, sub mucous and intra mural, uterine fibroids, caused retained placental tissue by distortion of the uterine cavity. Objectives of this study were to evaluate the feasibility of hysteroscopy to identify the retained placental products in cases of secondary postpartum haemorrhage. Verification of complete removal of RPP by reinsertion of hysteroscope, after removal of RPP by using a sponge holder, or curette.Methods: Trans vaginal ultrasonography (TVS) identified echogenic retained products of conception in all cases. Surgical profile investigations were done as per protocol. Transfusion of blood products was needed in some. Bettocchi 5 mm continuous flow hysteroscope (Karl Storz) was used. Storz endomat hysteroflator was used for irrigation and aspiration.Results: Hysteroscopic guided excision of the placental tissue was one-time treatment in four of study cases, and one needed a second hysteroscopic excision. Secondary PPH occurred at varying periods after the caesarean delivery, one week in one, two weeks in one case, three weeks in two cases and one woman was admitted with retained placenta, primary PPH continuing to secondary PPH. Hysteroscopy done during the puerperal period, in cases of secondary PPH, had certain challenges to cope with.Conclusions: Hysteroscopic guided excision of the retained placental tissue was successful in all the five cases with secondary postpartum haemorrhage. Hysteroscopy is an excellent procedure in cases of secondary PPH. We request guidelines committees to consider including hysteroscopic guided removal of retained placental products, in the algorithm of management of secondary PPH

Modeling and Analysis of Wind turbine Driven Self-Excited Induction Generator Connected to Grid Interface with Multilevel H-Bridge Inverter

This paper deals with the stator flux oriented vector control of wind driven self excited induction generator This paper presents an investigation of Hybrid nine level inverter (HNLI) used along with the voltage source rectifier unit as interface between Self excited induction generator and grid. Making use of HNLI benefits of low harmonics distortion, reduced number of switches to achieve the nine level output over the conventional cascaded nine level inverter and reduced switching losses results in improvement of the p.f at grid, to compensate the reactive power and to suppress the total harmonic reduction. The generated voltage of the wind driven self excited induction generator mainly depends on the wind velocity, appropriate excitation capacitance and grid conditions. The main objective of this paper is to track the maximum power of the grid connected SEIG driven by wind turbine. In previous literature there no discussion about the grid connected SEIG interface with the AC/DC link. The variable magnitude, variable frequency, voltage of the generator can be controlled by the proper modulation index.  The modulation index of the proposed HNLI is adjusted to obtain the maximum output power. The results are valid through MATLAB/SIMULINK software. Keywords: Self excited induction generator (SEIG), Wind turbine, Hybrid nine level inverter, voltage source rectifier, grid

Fixed combination of amlodipine and atorvastatin in cardiovascular risk management: patient perspectives

Hypertension and dyslipidemia are two of the most commonly co-occurring cardiovascular risk factors which together cause an increase in coronary heart disease-related events that is more than simply additive for anticipated event rates with each condition. Data have shown that even relatively small reductions in both blood pressure and cholesterol levels can lead to large reductions in the risk for cardiovascular events. However, though there are robust data on the beneficial effect of concomitant reduction in these risk factors, the reality is that this is achieved in <10% of patients. There is nonadherence with prescribed therapies with up to 50% of patients stopping their medications of their own volition for a variety of reasons. There is a reasonable evidence base to suggest that simplifying drug regimens and reducing pill burden will enhance patient adherence. The fixed-dose combination containing the antihypertensive agent amlodipine besylate and the statin atorvastatin is the first combination of its kind, which is both efficacious and safe and could potentially improve medication compliance, thereby improving the outcomes in these patients