Ion-cyclotron Resonance Heating Of Plasmas And Associated Longitudinal Cooling

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)We have investigated, via a 1-22 dimensional computer simulation, the possibility of forcing an initially isotropic, magnetized plasma into an anisotropic state by means of an external pump. Strong heating of the perpendicular ion temperature was observed together with a strong cooling of the longitudinal temperature. This mechanism could enhance particle trapping in tokamaks and increase confinement time in mirror machines. We use basic physical arguments to predict the maximum temperature ratio that can be obtained. © 1976 The American Physical Society.3612831FAPESP; São Paulo Research FoundationFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Solution Of The Urban Traffic Problem With Fixed Demand Using Inexact Restoration

Congested traffic has become a part of the day-to-day for the residents of big metropolitan centers. From an economic viewpoint, this problem has been causing huge financial damage and strategic measures must be taken to tackle it. An alternative means of solving the problem is the inclusion of toll charges on routes with a view to decongesting the road network. The mathematical formulation of this alternative involves the solving of an optimization problem with equilibrium constraints (MPEC). This work proposes an algorithm for the solution of this problem based on the strategy of inexact restoration.837-4019071918Andreani, R., Castro, S.L.C., Chela, J.L., Friedlander, A., Santos, S.A., Aninexact-restoration method for nonlinear bilevel programming problems (2009) Comput. Optim. Appl., 43, pp. 307-328Andreani, R., Martinez, J.M., Svaiter, B.F., On the Regularization of mixed complementarity problems (2000) Numerical Functional Analysis and Optimization, 21, pp. 589-600Andreani, R., Martinez, J.M., On the reformulation od Nonlinear Complementarity Problems using the Fischer-Burmeister function (1999) Applied Mathematics Letters, 12, pp. 7-12Andreani, R., Friedlander, A., Bound Constrained Smooth Optimization for Solving Variational Inequalities and Related Problems (2002) Annals of Operations Research, 116, pp. 179-198Arnott, R., Small, K., (1994) The economics of traffic congestion, , Boston College Working Papers in Economics 256, Boston College, Department of EconomicsBazarra, M.S., Sherali, H.D., Shetty, C.M., (1993) Nonlinear Programming: Theory and Algoritms, , Second Edition, John Wiley & Sons, New YorkBonnans, J.F., Shapiro, A., (2000) Perturbation Analysis of Optimization Problems, , Springer Series in Operations Research, SpringerBrotcorne, L., Labbé, M., Marcotte, P., Savard, G., A Bilevel Model for Toll Optimization on a Multicommodity Transportation Network (2001) Transportation Science, 35 (4), pp. 345-358Calamai, P.H., Vicente, L.N., Generating quadratic bilevel programming test problems (1994) ACM Transactions on Mathematical Software, 20, pp. 103-119Chela, J.L., (2006) Resolução do problem a de programao matemática com restrições de equilíbrio usando restauração inexata, , PhD thesis, University of CampinasFerrari, P., Road network toll pricing and social welfare (2002) Trans. Res. B, 36, pp. 471-483Harker, P.T., Pang, J.S., Existence of optimal solutions to mathematical programs with equilibrium constraints (1988) Operations Research Letters, 7 (2), pp. 61-64Hearn, D.W., (1980) Bounding Flows in Traffic Assignment Models, , Research report N.80-4, Dept. of Industrial and Systems Enginnering, University of Florida, Gainesville, FL 32611Hearn, D.W., Ramana, M.V., Solving congestion toll princing models (1998) Equilibrium and Advanced Transportation Modelling, pp. 109-124. , P. Marcotte, S. Nguyen (eds), Kluwer Academic Publisher, Boston, The NetherlandsHearn, D.W., Yildirim, M.B., A toll pricing framework for traffic assignment problems with elastic demands (2001) Current Trends in Transportation and Network Analysis: Miscellanea in Honor of Michael Florian, , M. Gendreau, P. Marcotte(eds), Kluwer Academic Publisher, Dordrecht, The NetherlandsHearn, D.W., Lawphongpanich, S., An MPEC approach to second-best toll pricing (2004) Mathematical Programming Series B, 101, pp. 33-55Hearn, D.W., Bergendorff, P., Ramana, M.V., Congestion Toll Pricing of Traffic Networks, Network Optimization (1997) Lecture Notes in Economics and Mathematical Systems, 450, pp. 51-71. , P. M. Pardalos, D.W. Hearn and W.W. Hager (Eds.), Springer-VerlagJohansson-Stenman, O., Sterner, T., What is the scope for environmental road pricing? (1998) Road pricing Traffic Congestion and Environment, , K.J. Button, E.T. Verhoef (eds.), Edward Elgar Publishing Limited, London, EnglandLabbé, M., Marcotte, P., Savard, G., A bilevel model of taxation and its application to optimal highway pricing (1998) Manage. Sci, 44 (12), pp. 1608-1622Migdalas, A., Bilevel Programming in traffic planning: models, methods and challenge (1994) Journal of Global Optimization, 4, pp. 340-357Patriksson, M., Rockafellar, R.T., A Mathematical model and descent algorithm for bilevel traffic management (2002) Trans. Sci, 36, pp. 271-291Solodov, M.V., Svaiter, B.F., A New Projection Method for Variational Inequality Problems (1999) SIAM Journal Control Optimization, 37, pp. 765-77

Transience analysis of bursty traffic with erbium doped fiber amplifiers

Copyright © [2009] IEEE. Reprinted from ICTON 2009. ISBN 978-1-4244-4826-5. This material is posted here with permission of the IEEE. Internal or personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution must be obtained from the IEEE by writing to [email protected]. By choosing to view this document, you agree to all provisions of the copyright laws protecting it.In this paper, we investigate experimentally the impact of optical amplifiers, namely Erbium Doped Fiber Amplifiers (EDFA) on Optical Burst Switching (OBS) networks, operating at 2.5 Gb/s (typical bit rate for current passive optical networks - PON). Bursts with 212 – 1 and 216 – 1 pseudo random binary sequence (PRBS) were studied, with different idle times. The use of traffic with variable idle time was assessed in order to evaluate the effect on the burst initial amplitude. We also analyzed the performance of the packet based system by measuring the Q factor at the receiver and concluded that the performance is not affected by the type of traffic (variable or fixed idle times)

Caracterização mecânica das argamassas de assentamento para alvenaria estrutural – previsão e modo de ruptura

Este trabalho pretende avaliar o comportamento mecânico das argamassas de assentamento para o uso estrutural, por meio das propriedades de resistência à compressão, tração na flexão e módulo de elasticidade, sob estados de tensões uniaxial e multiaxial. Portanto, estabelecer correlações entre os resultados mecânicos de diferentes traços de argamassas, relações água/cimento e geometria da amostra associada ao modo de ruptura. As principais conclusões obtidas, entre outras, são: existe uma relação potencial entre a resistência a compressão da amostra de geometria cúbica, cilíndrica e a resistência à flexão (amostra de geometria prismática) em função da relação água/cimento; a função linear é a que melhor ajusta os valores médios do módulo de elasticidade em função da resistência à compressão; a envoltória de ruptura da argamassa confinada lateralmente pode ser representada como uma relação linear de Mohr-Coulomb; observou-se, por meio de ensaios de microscopia eletrônica de varredura a existência de fissuras de retração na interface pasta-agregado e poros isolados, devido ao fluxo ascendente de água causado pela exsudação

High-Risk Human Papillomavirus Detection in Urine Samples from a Referral Population with Cervical Biopsy-Proven High-Grade Lesions

Objective The aim of the study was to evaluate the performance of the HPV-HR test to detect high-risk human papillomavirus (HPV) in urine samples in comparison with a commercial molecular HPV test. Materials and Methods This is a prospective study, in which 350 patients diagnosed previously with cervical intraepithelial neoplasia (CIN) grade 2 or higher were enrolled. Urine and cervical specimens were collected. Urine was tested with the HPV-HR test and cervical specimens were tested with the Cobas. Results Of the 336 evaluable patients, there were 271 cases of CIN 2+, of which 202 were CIN 3+ and the remaining 65 patients were less than CIN 2. Positivity was 77.1% (95% confidence interval [CI] = 72.5-81.5) for the urine samples and 83.6% (95% CI = 79.6-87.6) for the cervical samples. Agreement between cervical and urine samples for HPV detection was 79.8% (κ = 0.363; 95% CI = 0.243-0.484). Sensitivity for CIN 2+ was 83.4% (95% CI = 78.4-87.6) for urine and 90.8% (95% CI = 86.7-92.9) for cervical samples. The sensitivity for CIN 3+ was 85.6% (95% CI = 80.0-90.2) for urine and 92.6% (95% CI = 88.0-95.8) for cervical samples. Specificity for worse than CIN 2 was 50.8% (95% CI = 33.7-59.0) and 46.2% (95% CI = 33.7-59.0) for urine and cervical samples, respectively. Conclusions Although these results demonstrated slightly higher detection rates for HR-HPV and clinical sensitivity in cervical samples than in urine, when compared with histological diagnoses, urine sampling is a viable alternative to access women who do not participate in routine screening programs

Patterns of psychological responses among the public during the early phase of COVID-19: A cross-regional analysis

This study aimed to compare the mediation of psychological flexibility, prosociality and coping in the impacts of illness perceptions toward COVID-19 on mental health among seven regions. Convenience sampled online survey was conducted between April and June 2020 from 9130 citizens in 21 countries. Illness perceptions toward COVID-19, psychological flexibility, prosociality, coping and mental health, socio-demographics, lockdown-related variables and COVID-19 status were assessed. Results showed that psychological flexibility was the only significant mediator in the relationship between illness perceptions toward COVID-19 and mental health across all regions (all ps = 0.001–0.021). Seeking social support was the significant mediator across subgroups (all ps range = <0.001–0.005) except from the Hong Kong sample (p = 0.06) and the North and South American sample (p = 0.53). No mediation was found for problem-solving (except from the Northern European sample, p = 0.009). Prosociality was the significant mediator in the Hong Kong sample (p =0.016) and the Eastern European sample (p = 0.008). These findings indicate that fostering psychological flexibility may help to mitigate the adverse mental impacts of COVID-19 across regions. Roles of seeking social support, problem-solving and prosociality vary across regions. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

Modulation instability induced by cross-phase modulation in a dual-wavelength dispersion-managed soliton fiber ring laser

We report on the observation of modulation instability induced by cross-phase modulation in a dual-wavelength operation dispersion-managed soliton fiber ring laser with net negative cavity dispersion. The passively mode-locked operation is achieved by using nonlinear polarization rotation technique. A new type of dual-wavelength operation, where one is femtosecond pulse and the other is picosecond pulse operation, is obtained by properly rotating the polarization controllers. When the dual-wavelength pulses are simultaneously circulating in the laser ring cavity, a series of stable modulation sidebands appears in the picosecond pulse spectrum at longer wavelength with lower peak power due to modulation instability induced by cross-phase modulation between the two lasing wavelengths. Moreover, the intensities and wavelength shifts of the modulation sidebands can be tuned by varying the power of the femtosecond pulse or the lasing central wavelengths of the dual-wavelength pulses. The theoretical analysis of the modulation instability induced by cross-phase modulation in our fiber laser is also presented.Comment: 26 pages, 10 figure