Credit availability to construction sector entities determines for thin-capitalized construction firms the possibility of survival during the crisis and of efficient growth during the economic recovery. The main lenders for construction sector entities are commercial creditors (suppliers) and banks. Although their credit policies are similar, debt to commercial creditors dominate in the balance sheets of borrowers, because of customary business practices in construction industry and regulatory distinctions.
Keywords: information asymmetry, agency theory, trade credit
This paper presents key capital structure determinants of construction companies and their impact on fund raising and financing mix formation in accordance with the conditions of construction activity. It was found that profitability and tangibility have a positive effect on leverage, risk - the negative and the effect of company size, assets growth rate and taxes is ambiguous.
Keywords: capital structure determinants, profitability, risk, taxes, tangibility, construction companies
The article describes the main problems of circuit simulation. The problem of solving ill-conditioned systems of linear algebraic equations (SLAE) of large dimension. The modified algorithm is a linear algebraic solutions. Described a hybrid evolutionary algorithm for solving linear systems based on the proposed modified method. The results of the pilot study and comparison of the algorithm with the algorithms based on the traditional methods for solving linear algebraic equation, which confirm the advantages of the hybrid evolutionary algorithm.
Keywords: Genetic operators, evolutionary algorithm, the system of linear algebraic equations, computer-aided design.
The establishment of automated air monitoring systems is a promising way of the air monitoring devices development. The comparative analysis of literature has shown that thin films based on semiconductor metal oxides are effective and widely used material for air monitoring systems creation. In order to create effective and more sensitive sensors it is important to research processes that occur on the surface of the gas sensitive material when it contacts with different substances. The processes that proceed on the surface of gas sensitive material based on SiO2SnOxCuOy during the interaction with molecules of nitrogen dioxide. Quantum chemical calculations have shown that there are three possible mechanisms of interaction between the molecules of nitrogen dioxide with a surface of gas sensitive material.
Keywords: multitouch system of the monitoring, gas-sensitive material, molecules of dioxide of nitrogen
The mathematical model of the potential distribution in the semiconductor surficial region in the presence of deep-lying levels in its forbidden zone which specified by multiple-charge impurity centers has been developed. The simulation results can be used for the width of the space charge region estimation, for the prognostication of the most probable mechanism of the charge carriers transfer in metal-semiconductor structure with multiple-charge deep-lying levels and also for the prognostication of the barrier capacitance value. It can be used in the development of solid-state electronic devices with improved values of some parameters.
Keywords: Poisson’s equation, multiple-charge impurity center, potential distribution, deep-lying levels
Stability of sensors on the basis of inorganic oxide materials is one of the primary goals by working out of atmospheric air control devices. In this work long-term stability of a sensor response on the basis of the SiO2SnOxCuOy material to carbon oxide (II) exposure in a range of concentration 1-100 ppm is studied. It is shown that the sensor response differs high stability and reproducibility. Continuous heating within 21 days to working temperature (350°С) influence its value negligibly.
Keywords: stability of a response, sensor, carbon oxide, material of structure of SiO2SnOxCuOy.
Results of researches of gas sensitive properties of zinc oxide films grown by reactive rf magnetron sputtering was shown. Process parameters, affected on the gas-sensitive ratio, response time, recovery time and the type of electrical conductivity of obtained films were identified. Optimal modes of magnetron sputtering of zinc oxide for implementing gas sensors (RF sputtering Zn target in a gas mixture of oxygen and argon at a concentration of 80% oxygen, a chamber pressure of 0.8 Pa and the magnetron power 100 W) were established. Avarage response time on NO2 gas was 5-15 sec. The obtained values of the gas-sensitivity were in the range 30-67% for NO2 concentrations from 20 to 100 ppm, CO and CO2 from 50 to 100 ppm and 81-97% for higher gas concentrations from 500 to 1000 ppm.
Keywords: Nanotechnology, magnetron sputtering, zinc oxide, thin films, gas sensitivity
In this work researches of structural and electrophysical properties of ferroelectric films of lead zirconate titanate (PZT) which afterwards is planned to apply in hybrid sensor systems are done. Values of capacities of the received samples are in the range from 200 to 1100 pF, the range of thickness of the received films is 300-1000 nanometers. X-ray analysis showed direct dependence of the quantitative maintenance of crystalline PZT in film structure from partial pressure of oxygen in the camera. By results of research the range of polarization of samples are in the range 0,06 – 2,2 µC/cm2, and values of calculated piezoelectric modules are in the range 0,04*10-12 – 13,3*10-12 C/N.
Keywords: sensors, segnetoelektric films, touch systems, piezoelectric modules.
The article investigates the impact on the normal stresses of inequality of the young modulus for tension and compression in the bending of reinforced beams. Obtained formulas for determination of the bending moments that arise in the fixture, compressed and stretched zone of the aggregate. Found the formula for the normal stresses arbitrarily supported reinforced beams, arbitrary cross section and arbitrarily loaded bending loads. For example, reinforced beams of rectangular cross-section shows the determination of the neutral line and maximum stresses.
Keywords: reinforced beam, elastic modulus, stress, normal concrete
Cracking of reinforced-concrete elements with holes is examined. Comparison of theoretical and experiment moments of crack’s formation during torsion, and during intensive torsion with twist. Formula for practical calculations of cracking of reinforced-concrete elements with holes during torsion and formula for estimate of cracking of reinforced-concrete elements with holes during intensive torsion with twist is suggested.
Keywords: Crack, twist, torsion, reinforced-concrete, elements, hole, beam
A principle of spectrometric systems of gas sensors was described. A model and a method of numerical modeling of spectrometric gas sensor with the combined radiator-receiver of infrared radiation on the basis of the punched semiconductor thermoresistor were proposed.
Keywords: spectrometric gas sensor, model, method of modeling
We propose a method for cooling the condenser compression refrigerator, including the use of melt water wetting the surface of the water condenser. The water is directed into the groove in the middle part of which is the tube condenser coil, and the water flows by gravity to the tribes of the inclined groove, wetting the surface of the trough and tube condenser. Remains of meltwater routed to the tank on the compressor.
Keywords: Household refrigerating appliances, water, cooling, condenser, reducing energy consumption
In this article the mathematical model dynamic process installations for blast cleaning the surface, and clearly showed the graph of the transition process, given the theoretical integer parameters yield in the specific process conditions.
Keywords: Fluid Technology, a dynamic characteristic of the drive, nozzle - gate, jetting processing surface
Article focuses on the use of statistical models to predict tolerability surgery using intracavitary hyperthermic chemotherapy (IHCT) and the definition of indications and contraindications to perform operations and tolerability for patients with cancer based on the hemostatic patient. This technique allows a high enough accuracy to prediction portability planned surgery, duration of disease-free period, the period and quality of life in the immediate and late postoperative period.Improve treatment of patients with malignant tumors of the abdomen and pelvis, is one of the priorities of modern health care. Relevance of various parameters of immunity, clinical and biological parameters of homeostasis and prognosis of malignant disease in humans will significantly reduce the proportion of late diagnoses of relapses. Recently there has been increased research to find a method of complex cytoreductive surgery and the use of cytotoxic drugs, and physical therapies, one of which is a local intraoperative hyperthermic chemotherapy. With the help of statistical methods has been studied the degree of influence on the parameters IHCT immunity and an estimate of the nature of the immunological changes in different types of surgery. Methods of binary logistic regression analysis was calculated diskriminatnogo forecast portability operation - patient survival probability. Based on the method of multiple regression were obtained algorithms calculate the duration of life of patients after surgery, and the duration of DFS. Studies based on the factor analysis showed that the main factors affecting the prognosis of disease-free period and the period of life are the morphological structure of the tumor volume cytoreduction, the sum of your immune system and cancer markers. Peritoneal cancer index, sex and age of the patient does not have a significant effect on these parameters. Thus, the introduction into clinical practice of the proposed computer systems and statistical forecasting models allow physicians to objectively evaluate the performance of homeostasis, the portability of the planned surgery, more accurately predict the course of the cancer disease and the likelihood of recurrence of the disease and the duration and quality of life.
Keywords: statistics, modeling, forecasting, surgery, colorectal cancer, disease-free life expectancy, tolerance of surgery, immunological parameters, factor analysis, regression equation
To create in Rostov-on-Don, ecologically effective, technologically advanced and durable green plantings to solve the problem: 1. Create a variety of trees for landscaping cities and towns; 2. Determine the principles of green plantings, ensuring their maximum environmental efficiency. In the steppe zone of Russia should use the structure of the park, with a high proportion of dense plantings (400 trees per hectare) of long-lived trees of the first magnitude.
Keywords: green building, greening cities, assortment of trees, ecologically effective green plantings, the steppe zone