Сравнительный анализ методик количественного определения окалинообразования в металлургическом переделе

Материалы XIII Междунар. науч.-техн. конф. студентов, магистрантов и молодых ученых, Гомель, 25–26 апр. 2013

Сучасні методи дослідження нелінійних коливань

(ru) Рассмотрены колебания консервативной системы. Предложен метод численного отыскания периода колебаний. Исследуются также колебания в нелинейных системах, рассматривается проблема центра-фокуса, получено численное решение дифференциальных уравнений и построены фазовые траектории. Рассмотрено уравнение Ван дер Поля и методы его исследования.(en) The vibrations of the conservative system are considered. The method of the numeral searching of period of vibrations is offered. Vibrations are also probed in the nonlinear systems, the problem of center-focus is examined, got numeral decision of differential equklizations and phase trajectories are built. Equklization of Van der Paul and methods of his research is considered

Characteristics of variable speed limit systems

The control algorithm used for deciding on the speed limit in variable speed limit systems is crucial for the performance of the systems. The algorithm is designed to fulfil the purpose of the variable speed limit system, which can be one or several of the following aspects: increasing safety, increasing efficiency and decreasing environmental impacts. Today, many of the control algorithms used in practice are based on fixed thresholds in speed and/or flow. Therefore, they are not necessarily reflecting the current traffic conditions. Control algorithms with a greater level of complexity can be found in the literature. In this paper, four existing control algorithms are investigated to conclude on important characteristics affecting the performance of the variable speed limit system. The purpose of the variable speed limit system and, consequently, the design of the control algorithm differ. Requirements of the investigated control algorithms are that they should be easy to interpret and the execution time should be short. The algorithms are evaluated through microscopic traffic simulation. Performance indicators related to traffic safety, traffic efficiency and environmental impacts are presented. The results show that the characteristics of the variable speed limit system and the design of the control algorithm will have effect on the resulting traffic performance, given that the drivers comply with the variable speed limits. Moreover, the time needed to trigger the system, the duration and the size of speed limit reductions, and the location of the congestion are factors of importance for the performance of variable speed limit systems. "p"Funding Agencies|Swedish Transportation Administration (Trafikverket) Document type: Articl

Coordinated responses of natural anticoagulants to allogeneic stem cell transplantation and acute GVHD - A longitudinal study

Background Allogeneic stem cell transplantation (SCT) enhances coagulation via endothelial perturbation and inflammation. Role of natural anticoagulants in interactions between coagulation and inflammation as well as in acute graft-versus-host disease (GVHD) are not well known. The purpose of this study was to define changes in natural anticoagulants over time in association with GVHD. Patients and methods This prospective study included 30 patients who received grafts from siblings (n = 19) or unrelated donors (n = 11). Eight patients developed GVHD. Standard clinical assays were applied to measure natural anticoagulants, represented by protein C (PC), antithrombin (AT), protein S (PS), complex of activated PC with its inhibitor (APC-PCI) and by markers of endothelial activation: Factor VIII coagulant activity (FVIII: C) and soluble thrombomodulin (s-TM) at 6-8 time points over three months. Results Overall, PC, AT and FVIII: C increased in parallel after engraftment. Significant correlations between PC and FVIII: C (r = 0.64-0.82, p Conclusion The coordinated activation of natural anticoagulants in our longitudinal study indicates the sustained ability of adaptation to endothelial and inflammatory activation during allogenic SCT treatment. The suboptimal control of coagulation by natural anticoagulants at early stage of SCT may contribute to onset of GVHD.Peer reviewe