Performance Analysis of an OFDMA Transmission System in a Multicell Environment

The paper deals with design and performance analysis of orthogonal frequency-division multiple-access (OFDMA)-based downlink cellular wireless communications. Due to a high degree of user mobility, the base station is assumed to have only a statistical knowledge of the users' channels. Relying on the ergodic capacities connected to the user rates, a subcarrier and power allocation that minimizes the total transmitted power is proposed. The allocation strategy requires only the knowledge of the channel statistics and the rate requirements for all users. An extension and a performance analysis of this allocation algorithm in a multicell environment working with a frequency reuse factor equal to one is also conducted. A condition for the multicell network to be able to satisfy all rate requirements is derived     

QuicK-means: accelerating inference for K-means by learning fast transforms

Machine Learning - K-means—and the celebrated Lloyd’s algorithm—is more than the clustering method it was originally designed to be. It has indeed proven pivotal to help increase...     

Listing all maximal cliques in large graphs on vertex-centric model

The Journal of Supercomputing - Maximal Clique Enumeration (MCE), which consists to enumerate all maximal complete subgraphs in a given graph, is a fundamental problem in graph theory, and it is...     

A prospective crossover randomized trial of novobiocin and rifampin prophylaxis for the prevention of intravascular catheter infections in cancer patients treated with interleukin-2

BACKGROUND: The aim of this study was to determine the efficacy of novobiocin and rifampin as oral antibiotic prophylaxis for the prevention of catheter-related infection in melanoma patients treated with interleukin-2 (IL-2) plus interferon-alpha and chemotherapy (biochemotherapy). METHODS: Patients with advanced melanoma who were treated with biochemotherapy at the University of Texas M. D. Anderson Cancer Center were randomized in a crossover study to receive either oral antibiotic prophylaxis consisting of novobiocin and rifampin or observation alone over a 35-day course period. Patients were subsequently "crossed over" to the opposite arm of the study for an additional 35-day period, with each serving as his or her own control. RESULTS: Twenty-six patients were enrolled. Nine patients (35%) failed to tolerate oral antibiotics because of severe nausea and vomiting; 17 patients (65%) were crossed over and considered evaluable. During the control patient courses, 71% of evaluable patients had infectious complications, 41% had a catheter-associated bacteremia, and 53% had a local catheter infection. In contrast, of the patients treated with antibiotic prophylaxis, only 12% had an infectious complication (P = 0.001), 12% had a local catheter infection (P = 0.008), and 6% had catheter-associated bacteremias (P = 0.04). Thirty-six episodes of catheter infections occurred during the 17 control courses, whereas only 3 episodes occurred during antibiotic prophylaxis (P < 0.001). CONCLUSIONS: Although more than one-third of patients receiving IL-2 treatment with biochemotherapy failed to tolerate novobiocin and rifampin, this oral antibiotic regimen was efficacious in preventing the infectious complications, especially those associated with vascular catheters, in this high risk patient population.     

Towards a holistic sustainability index for measuring sustainability of manufacturing companies

Competition from low wage countries and the adoption of free market strategies have forced manufacturing firms to recognise and implement productivity enhancement strategies. This research defines a holistic sustainability index embedding several performance indices. The aim of this study was to establish a relevant framework that would assess the current situation of an industry through aggregation of environmental, social, economical as well as manufacturing variables. The proposition has its roots in trends and gaps in the sustainability literature of manufacturing industries and is based on the analytic hierarchy process (AHP) method. A list of indicators measuring the industry performance based on an AHP scoring methodology is proposed. The next stages include grouping industries according to common deficiencies across the four dimensions and establishing a cooperation framework. The food manufacturing industry is the main target in this study and will benefit from adopting sustainable long-term policies. By recognising the importance of social–environmental sustainability and taking the initiative to pursue it, profits will grow as a positive effect of such policies. The added value is twofold: (1) coupling all sustainability dimensions, often addressed in silos and (2) integrating manufacturing indicators which enable the analysis of interrelationships with sustainability.     

Transport and storage of Helicobacter pylori from gastric mucosal biopsies and clinical isolates

Presence of multivessel coronary artery disease (MVD) identifies a high risk subgroup after acute myocardial infarction (AMI). Dobutamine stress echocardiography (DSE) has recently emerged as a promising non invasive test to detect the presence and extent of coronary artery disease. Forty six consecutive patients (38 males, 8 females; mean age 48.6 +/- 10.4 years) of Q-wave acute myocardial infarction were subjected to submaximal treadmill test (TMT) and dobutamine stress echocardiography to see their ability to predict multivessel coronary artery disease as detected by coronary angiography before hospital discharge. Dobutamine infusion was started at 5 micrograms/kg/min to a maximum of 40 micrograms/kg/min, to achieve 70 percent of the age predicted heart rate. Appearance of new regional wall motion abnormality was interpreted as positive DSE for MVD. Mean peak infusion dose of dobutamine used in the study was 28.56 +/- 5.67 micrograms/kg/min. In none of the patients, the test had to be terminated due to side effects. The sensitivity and specificity of DSE to predict MVD was 80 percent and 93.7 percent, respectively as compared to 45 percent and 86 percent for submaximal TMT. Thus, DSE in patients of AMI before hospital discharge is a safe procedure with fairly accurate prediction of multivessel coronary artery disease.     

Intelligent data analysis systems

A variety of approaches to the intelligent analysis of complex manufacturing data have been described in the literature. A comparative analysis of these systems reveals underlying similarities in their functional organizations. This leads to the development of a general functional model for intelligent data analysis (IDA).This article describes the various data analysis systems studied, the general model for IDA, and the implementation of a demonstration IDA system. The implementation serves to demonstrate the feasibility of this approach, and provides directions for further research.     

Monte Carlo simulation of a medical linear accelerator for radiotherapy use

A Monte Carlo code MCNPX (Monte Carlo N-particle) was used to model a 25 MV photon beam from a PRIMUS (KD2-Siemens) medical linear electron accelerator at the Centre Antoine Lacassagne in Nice. The entire geometry including the accelerator head and the water phantom was simulated to calculate the dose profile and the relative depth-dose distribution. The measurements were done using an ionisation chamber in water for different square field ranges. The first results show that the mean electron beam energy is not 19 MeV as mentioned by Siemens. The adjustment between the Monte Carlo calculated and measured data is obtained when the mean electron beam energy is approximately 15 MeV. These encouraging results will permit to check calculation data given by the treatment planning system, especially for small fields in high gradient heterogeneous zones, typical for intensity modulated radiation therapy technique.     

Improvement of the early-age reactivity of fly ash and blast furnace slag cementitious systems using limestone filler

This article analyzes the effects of the addition of limestone filler on the hydration rate, setting times and early-age mechanical properties of binary and ternary-binder mortars containing Portland cement, blast furnace slag (BFS) and fly ash (FA), with various substitution rates of cement with mineral additions going up to 50%. Vicat needle penetration tests and measurements of heat flow of reaction, compressive strength and dynamic Young’s modulus were carried out on 14 mortars prepared with binary and ternary binders, at 20°C. The results obtained on the mortars containing binary binders, show that their loss of mechanical strength at early age is not caused by a deceleration of the reactions of cement in the presence of mineral additions, but is mainly explained by the dilution effect related to the reduction in cement content. A moderate addition of limestone filler (8–17%) makes it possible to obtain ternary binders with early-age reactivity equal or even higher than that of Portland cement, and with 28-days mechanical resistance close to those of the binary-binder mortars. This accelerating effect of limestone filler is particularly sensitive in the case of mortars containing FA.     

MMSE analysis of certain large isometric random precoded systems

Linear precoding consists in multiplying by an N/spl times/K matrix a K-dimensional vector obtained by serial-to-parallel conversion of a symbol sequence to be transmitted. In this paper, new tools, borrowed from the so-called free probability theory, are introduced for the purpose of analyzing the performance of minimum mean-square error (MMSE) receivers for certain large random isometric precoded systems on fading channels. The isometric condition represents the case of precoding matrices with orthonormal columns. It is shown in this contribution that the signal-to-interference-plus-noise ratio (SINR) at the equalizer output converges almost surely to a deterministic value depending on the probability distribution of the channel coefficients when N/spl rarr/+/spl infin/ and K/N/spl rarr//spl alpha//spl les/1. These asymptotic results are used to analyze the impact of orthogonal spreading as well as to optimally balance the redundancy introduced between linear precoding versus classical convolutional coding, while preserving a simple MMSE equalization scheme at the receiver.