71 research outputs found

    Optimal configuration algorithm of a satellite transponder

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    This paper describes the algorithm of determining the optimal transponder configuration of the communication satellite while in service. This method uses a mathematical model of the pay load scheme based on the finite-state machine. The repeater scheme is shown as a weighted oriented graph that is represented as plexus in the program view. This paper considers an algorithm example for application with a typical transparent repeater scheme. In addition, the complexity of the current algorithm has been calculated. The main peculiarity of this algorithm is that it takes into account the functionality and state of devices, reserved equipment and input-output ports ranged in accordance with their priority. All described limitations allow a significant decrease in possible payload commutation variants and enable a satellite operator to make reconfiguration solutions operatively

    Improvement of firebrand tracking and detection software

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    Burning and glowing firebrands generated by wildland and urban fires may lead to the initiation of spot fnes and the ignition of structures. One of the ways to obtain this infonnation is to process tliennal video files. Earlier, a number of algorithms were developed for the analysis of the characteristics of fu'ebrands under field conditions. However, they had certain disadvantages. In this regard, this work is devoted to the development of new algorithms and their testing

    A simplified Bixon-Jortner-Plotnikov method for fast calculation of radiationless transfer rates in symmetric molecules

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    A simplified form of the Bixon-Jortner-Plotnikov (BJP) method is derived for calculation of internal conversion (IC) rate in a symmetrical molecule. The rate is a sum of contributions from individual transitions between vibronic states. For each transition, vibrational modes are divided into two groups, the promoting (one or two modes per electronic transition) and the surrounding ones. In the case of the non-totally symmetric transition in a symmetric molecule, the overwhelming majority of transitions do not contribute to the overall rate. Moreover, the promoting and surrounding modes belong to different symmetry representations and can be separated. It is proposed to deal with the promoting modes directly, while approximating the effect of the surrounding modes by a Pekarian function. The method was tested on polyacenes and it was shown that the calculated IC rates are in agreement with the experimental ones. The simplified method can be applied for calculating the rates of non-totally symmetric transition in a symmetric molecule, if its point symmetry group does not change after transition

    Using non-adiabatic excitation transfer for signal transmission between molecular logic gates

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    Molecular logic gates (MLG) are molecules which perform logic operations. Their integration into a computing system is a very difficult task which remains to be addressed. The problem lies in the field of signal exchange between the gates within the system. We propose using non-adiabatic excitation transfer between the gates to address this problem while absorption and fluorescence are left to communicate with external devices. Excitation transfer was studied using the modified Bixon-Jortner- Plotnikov theory on the example of the 3H-thioxanthene-TTF-dibenzo-BODIPY covalently linked triade. Several designs of the molecule were studied in vacuum and cyclohexane. It was found that the molecular logic system has to be planar and rigid to isolate radiative interfaces from other gates. Functioning of these gates is based on dark πσ∗-states in contrast to bright ππ∗-states of radiative interfaces. There are no fundamental difference between ππ∗ → πσ∗ and ππ∗ → ππ∗ transitions for cases when an exciton hopes from one gate to another. The rates of such transitions depend only on an energy gap between states and a distance between gates. A circuit is highly sensitive to the choice of solvent which could rearrange its state structure thereby altering its behavior. According to the obtained results, non-adiabatic transfer can be considered as one of the possible ways for transmitting a signal between MLGs

    Comparison of Colorimetric and Fluorometric Chemosensors for Protein Concentration Determination and Approaches for Estimation of Their Limits of Detection

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    Here, we present a direct comparison of different dyes and assays for the determination of protein concentrations. We compared the classical Bradford assay with two modern assays based on the fluorogenic dyes QuDye and ProteOrange and showed that the Bradford reagent achieved excellent results in the determination of protein concentrations as compared with more modern rivals. We also showed that standard approaches for determining the limit of detection (LoD) and limit of quantification (LoQ) may not work correctly with the tested dyes. We proposed a new approach that extends the standard algorithm for LoD and LoQ determination. This approach works well with both classical colorimetric and fluorogenic dyes, as well as with nontrivial fluorescent probes

    Improvement of firebrand tracking and detection software

    Get PDF
    Burning and glowing firebrands generated by wildland and urban fires may lead to the initiation of spot fnes and the ignition of structures. One of the ways to obtain this infonnation is to process tliennal video files. Earlier, a number of algorithms were developed for the analysis of the characteristics of fu'ebrands under field conditions. However, they had certain disadvantages. In this regard, this work is devoted to the development of new algorithms and their testing

    Features of the course of COVID-19 in patients with type 2 diabetes mellitus

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    Aim. To identify the features of the course of COVID-19 in patients with type 2 diabetes mellitus (T2DM), depending on the intake of hypoglycemic therapy at the prehospital stage, in conjunction with the functional state of the kidneys. Materials and methods. A retrospective analysis of 291 case histories of patients with COVID-19 and T2DM hospitalized in the infection department of Semashko Regional Clinical Hospital from January to December 2021, including the main clinical and laboratory parameters. Results. Among hospitalized patients with COVID-19, patients with T2DM had a higher mortality rate. An analysis of the case histories of deceased patients with COVID-19 and T2DM showed that at admission, body mass index (BMI), C-reactive protein, and creatinine were higher than those of survivors and amounted to BMI – 33 [30; 39] and 33 [28; 36] kg/m3; p=0.039, C-reactive protein – 77 [47.5; 106.0] and 57 [27.0; 89.0] mg/l; p=0.015, in terms of creatinine level – 89 [70.0; 144.0] and 82 [66.0; 101.0] µmol/l; p=0.039, respectively. It was found that in the second week of hospitalization in the group of deceased patients with COVID-19 and T2DM, the creatinine level was statistically significantly higher than in surviving patients and amounted to 94.5 [71.5; 141.0] and 72.5 [57.0; 88.0] µmol/L; p0.001, respectively. The probability of death in hospitalized patients with type 2 COVID-19 and T2DM depended on BMI and creatinine levels at the second week of hospitalization. Patients with prehospital correction of hyperglycemia dipeptidyl peptidase-4 inhibitors (iDPP-4)/ glucagon-like peptide-1 receptor agonists (agGLP-1)/ sodium-glucose co-transporter 2 inhibitors (iSGLT-2) had significantly lower creatinine levels at week 2 of hospitalization. Conclusion. In patients with moderate to severe COVID-19 with concomitant T2DM, special attention should be paid to the combination of high BMI and creatinine in the second week of hospitalization, which is a prognostically unfavorable predictor of death in such patients
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