bluuebunny/crossref_metadata_2025_split huggingface dataset:
EFFECT OF WATER TEMPERATURE AT INLET TO THE STEAM GENERATING CHANNEL ON STABILITY OF THE TWO-PHASE FLOW
Authors: Kovetskaya M.M. 
Published: June 2019

The paper considers the influence of the coolant temperature on stability of the flow in the closed loop of thermal-hydraulic test bench in the natural circulation mode. The loop includes a lifting section with a heated and unheated zone, condenser and lowering section where the single-phase coolant flows. The regime is considered, when the heat flow on the wall of the heated channel remains constant and the temperature of the coolant inlet increases.
The effect of underheating at entrance to heated channel on the stability of the natural circulation of the coolant is considered. A one dimensional unsteady mathematical model of a two-phase coolant flow is presented. Boundaries of natural circulation instability region are determined depending on the coolant underheating at the entrance to the heated channel. Fluctuations in coolant flow rate are characterized by regular shape and an antiphase change in the flow rate at the outlet.
The ambiguous effect of underheating of the coolant at the entrance to the steam generating channel on the boundary of the stability of a two-phase flow is shown: at low values of underheating, its increasing destabilizes flow; at large underheating its increasing stabilizes the flow.
DEVELOPMENT AND VERIFICATION OF APPROPRIATENESS FOR MATHEMATICAL MODEL OF HEAT BALANCE OF ELECTROTHERMAL FLUIDIZED BED REACTOR
Authors: Simeiko K.V. 
Published: June 2019

Supply of heat through combustion of organic fuel is impossible or economically unviable for the raw of high temperature processes due to it’s technological peculiarities. Some of these processes can be carried out in electrothermal fluidized bed reactors. Development of appropriate mathematical model for heat balance will allow prognostication of capacity needed to carry out specific process and improvement of electrothermal fluidized bed reactor.
During the development of mathematical model methods of heat-mass exchange theory were applied. Verification of appropriateness for mathematical model was carried out through comparison of experimental results and calculated values of the amount of heat needed to perform the process of methane pyrolysis in electrothermal fluidized bed and coefficient of thermal efficiency of electrothermal fluidized bed reactor.
Comparison with real thermochemical process in electrothermal fluidized bed reactor confirms the appropriateness of mathematical model. Average deviation of mathematical model of heat balance and coefficient of thermal efficiency from obtained experimental values is 5…7 % and 6…9 % respectively. Proposed mathematical model can be applied in design of electrothermal fluidized bed reactors.
REDUCTION OF NATURAL GAS CONSUMPTION AND REDUCTION OF EMISSIONS WITH COMBUSTION PRODUCTS IN MUNICIPAL HEAT SUPPLY
Authors: Sigal O. , Pavlyuk N. , Pashyhin S. 
Published: June 2019

The technical solutions are proposed to reduce the consumption of natural gas, as well as to reduce emissions with combustion products in the municipal heat supply systems:
- New constructions of water-tube and water-fire-tube boilers with improved technical, economic and environmental characteristics have been developed. Replacing of old boilers with these boilers within Ukraine will provide an economic effect of about 100 thousand tons of fuel equivalent per year. NOx reduction will be up to 35%;
- The new temperature mode for heating networks 115/70 oС has been developed, which provides the amount of heat that is adequate to the needs of consumers, and is appropriate for use in cities of the country from an economic point of view. However, the implementation of such reduced temperature mode requires a corresponding change in the general requirements when issuing "Technical Specifications" for connection to district heating systems, necessitates changes in the temperature mode values in other documents, for example the general plan of the city, as well as the possible need to change the calculated heat loads in concluded contracts for heat supply to consumers. Nevertheless, the correction of temperature modes of cities should be considered as one of the possible measures to improve the energy efficiency of heat supply systems;
- The expediency of partial replacement of natural gas in the municipal heat supply systems of large cities of Ukraine with municipal solid waste (MSW) has been proved. The ways of improving the efficiency of mixed MSW combustion in conditions of country, including the extraction of "wet" biowaste from the total mass of mixed MSW with using a separate collection. are determined;
- To achieve compliance with the new more stringent European environmental standards, the highly efficient devices for cleaning combustion products from particulate matter and sulfur oxides have been developed. The efficiency of dust removal in centrifugal filters is 90...98%, in cyclone dust collectors - 90...93%. Desulfurization efficiency is up to 50%.
Zones of intensive interactions over the North Atlantic, 700 hPa level, November
Authors: Serga E. N. , Serga I. N. 
Published: June 2019

The methods of cluster and component analysis were applied to the existing factors that are associated with the characteristics of heat and moisture exchange at 700 hPa level before their inclusion in the model of regional climates imitation, in order to detect zones of active interaction in the atmosphere over the North Atlantic and determine the regions hosting the processes that cause a significant impact on formation of features of climatic responsive regimes in the Eastern Europe. Each node of a 2,5º2,5º grid covering the North Atlantic has the first three main components identified and they describe more than 80 % of the total dispersion of the interaction processes at 700 hPa level. Using the Universal Iterative Method of data clustering the study defines the homogeneous regions in the fields of main components of vectors of state of meteorological characteristics at 700 hPa level over the North Atlantic. It also specifies a physical and statistical analysis of the obtained clustering schemes which has a good scientific substantiation and shows that the clusters of the first main component are of a large-scale type, and the second and third components have a focal character. At 700 hPa level clusters differ in the intensity of interaction processes. The intensity of processes is characterized by distribution and magnitude of weight loads, average values of representative vectors and intra-cluster dispersion. We determined that the first main component makes the basic contribution to the formation of the majority of initial meteorological values, and the third main component reflects the influence of local features on interaction processes. These facts are confirmed by the manner in which loads over the studied region are distributed on the initial characteristics of atmospheric processes. Intra-cluster dispersion reflects the degree of diversity of these processes by region. The study identifies correspondence of the high-altitude homogeneous zones of the main components to the near-surface cyclic energy-active ocean zones.
Impulse Noise Parameter Assessment in a Batch Radio Channel
Authors: Bekkiev A. Yu. , Makoviy V. A. 
Published: June 2019

Modern radio communication means to provide safe data transmission due to adapting radio channel to the actual noise environment. It is impossible to conduct proper comparative tests on various radio stations offered by manufacturers and to compare objectively the results obtained in field without actual signal parameters and noise environment instrument inspection at the reception point. The paper considers tactical level radio communications system operation when jammed with powerful impulse noise of various nature. It suggests a device enabling to assess the main parameters of impulse noise, namely desired signal and additive noise mixture envelope effective value, impulse noise envelope effective value, impulse noise duty factor. To provide measurement independence from a specific realization of a decoder it is suggested to use the envelope of a signal received by a radio station. The developed device uses standard radio channel data batches as measuring signals and does not require changing radio channel or radio network algorithms and timing charts. A method to assess the effective value of desired signal envelope and additive noise mean-square value when the received signal involves impulse noise is suggested. The paper demonstrates that valid assessment of desired signal and additive noise mixture is possible in case of setting aside selection values affected by impulse noise. A device separating symbols affected by impulse noise from those that are not affected is suggested. Formulas that allow synthesizing the device operation algorithms are obtained. The structure chart of the measurer is developed; the algorithms used to assess measured parameters are given.
The Stand for Research of Positional-Sensitive Photosensor
Authors: Chukita V. I. , Senokosov E. A. , Feshchenko V. S. 
Published: June 2019

The paper considers position-sensitive photodetectors (PSP), which are designed to detect the source of electromagnetic radiation in the optical range and determine the coordinates of the irradiated area in real time, as well as to track moving optical objects. In particular, data are presented on photodetectors based on photosensitive epitaxial CdSe/mica layers with an unconventional layout and switching of electrical contacts. The output signal of such PSP is the transverse potential difference that appears between its two contacts after exposure of one of the areas of the photodetector. These PSPs can be an alternative or competition to existing photocells due to high accuracy, speed, ease of manufacture and low cost. But there are significant obstacles for their wide application. First, it is an analog type of output signal, which prevents its further processing. And, second, it is difficult to calibrate “manually” a newly made photosensor: it takes a long time associated with the accumulation and processing of large amounts of data. The introduction of computer technology and the creation of an information-measuring system allow us to process the output signals of such photodetectors with high accuracy and speed in real time. To solve this problem we have developed a stand for the study of position-sensitive photodetectors, which is presented in this paper. This stand allows digitizing the signal received from the photodetector, in real time, with high accuracy to determine the coordinates of the irradiated area on the photodetector and explore its characteristics such as the specified value of the dark current of the photodetector, light current at a certain illumination, and output voltage. At this stand, position-sensitive photodetectors based on the CdS/mica system were studied. It is shown that the characteristics and parameters of photoreceivers measured on this stand coincide with theoretical ones, within the error limits. Recommendations on the use of the standare given.
Stochastic and Percolating Models of Blocking Computer Networks Dynamics during Distribution of Epidemics of Evolutionary Computer Viruses
Authors: Lesko S. A. , Alyoshkin A. S. , Filatov V. V. 
Published: June 2019

The paper presents a complex model of the dynamics of virus epidemies propagation in computer networks, based on topological properties of computer networks and mechanisms of the viruses spread. On one hand, this model is based on the use of percolation theory methods, which makes it possible to determine such structural-information characteristics of networks as the dependence of the percolation threshold on the average number of connections per one node (network density). On the other hand, the dynamic processes of stochastic propagation in computer networks of evolving viruses are observed when anti-virus programs become outdated and postponed. The paper discusses the concept of percolation threshold, provides an equation for the dependence of the percolation threshold of a network on its density obtained by analyzing numerical simulation data. The dynamics of virus epidemies were studied through two approaches. The first one is based on the description of transition diagrams between states of nodes, after which a system of kinetic differential equations for the virus epidemies is constructed. The second is based on considering the probabilities of transitions between possible states of the entire network. A second-order differential equation is obtained in this article, and a boundary value problem is formulated. Its solution describes the dependence of the network blocking probability on the blocking probability of an individual node. The solution also makes it possible to estimate the time required to reach the percolation threshold. The model incorporates the evolutionary properties of viruses: previously immunized or disinfected nodes can be infected again after a certain time interval. Besides, the model incorporates a lag of the anti-virus protection. Analysis of the solutions obtained for the models created shows the possibility of various modes of virus propagation. Moreover, with some sets of values of differential equation coefficients, an oscillating and almost periodic nature of virus epidemies is observed, which largely coincides with real observations.
Dynamic Programming as a Method of Spline Approximation in the CAD Systems of Linear Constructions
Authors: Karpov D. A. , Struchenkov V. I. 
Published: June 2019

Under study is a problem of the line structure routing of roads, railways and other linear constructions. Designing a trace plan and longitudinal profile are considered as non-linear programming tasks. Since the number of elements of the plan and the longitudinal profile is not known, the problem is solved in three stages. First, a search is performed for a polyline consisting of short elements. On the second stage it is used to determine the initial approximation of the desired line, which is optimized at the last stage. The required line consists of a given type elements and it is a spline with a number of features:- In contrast to the polynomial elements considered in the theory of splines, when designing roads unknown spline is a sequence of elements: straight, clothoid, circle, clothoid, straight and so on.- In this task, the spline does not have to be a single-valued function.- The parameters of the elements of the desired spline must satisfy the constraints in the form of inequalities.These features of the task do not allow the use of non-linear programming methods to solve it. Converting a broken line to a spline is carried out using dynamic programming. For this purpose a special formalization of this task is proposed. A new algorithm of dynamic programming is given. The result is used as an initial approximation to optimize the parameters of the spline using a previously developed non-linear programming program.
The anxiolytic and analgesic effects of melatonin: a study protocol for a randomized, double-blind, placebo-controlled study
Authors: Kollerup Madsen Bennedikte , Zetner Dennis , Andersen Lars Peter Kloster , Rosenberg Jacob 
Published: June 2019

Anxiety and pain are both significant clinical challenges following surgery. Melatonin has been demonstrated to have both anxiolytic and analgesic effects in numerous experimental and clinical studies. This study protocol aims to present the design of a randomized study investigating the anxiolytic and analgesic effects of exogenous melatonin in cosmetic breast augmentation. The study will be a randomized, double-blind, placebo-controlled trial. Included patients are candidates for primary breast augmentation or replacement of existing implants. Patients receive a standardized general anesthetic and postoperative analgesic regimen. The study medication includes 4 separate doses, containing either 10 mg of melatonin or placebo. Doses are administered orally at 21:00 hours of the night before surgery, 120 minutes before surgery, immediately after surgery in the post-anesthesia care unit, and at 21:00 hours of the night following surgery. The two primary outcomes are preoperative anxiety, assessed by the State-Trait Anxiety Inventory and pain, measured by an integrated assessment of longitudinally measured pain intensity and opioid consumption. Secondary outcomes are VAS anxiety, and VAS pain, sleep quality, general fatigue and wellbeing. This study protocol presents in detail the design of a randomized, double-blind, placebo-controlled study investigating the anxiolytic and analgesic effects of repeated doses of exogenous melatonin in patients undergoing cosmetic breast augmentation.
Are melatonin doses employed clinically adequate for melatonin-induced cytoprotection?
Authors: Cardinali Daniel Pedro 
Published: June 2019

This review article discusses the special role that melatonin, a molecule with
chronobiotic/cytoprotective properties, may have in prevention and treatment of
the metabolic syndrome (MS), ischemic and non-ischemic cardiovascular diseases
and Alzheimer´s disease (AD). Prevention of these diseases is a major goal for
governmental and non-governmental organizations, and melatonin, an unusual
phylogenetically conserved molecule present in all aerobic organisms, merits
consideration in this respect. In humans, circulating melatonin levels are consistently
reduced in MS, ischemic and non-ischemic cardiovascular diseases and AD, the
potential therapeutic value of melatonin being suggested by a limited number of
clinical trials generally employing melatonin in the 2-5 mg/day range. In
animal model studies of MS, ischemic and non-ischemic cardiovascular diseases
and AD melatonin was very effective to curtail symptomatology. However,
calculations derived from animal studies indicate projected cytoprotective
melatonin doses for humans in the 40-100 mg/day range, doses that are rarely
employed clinically. Hence, controlled studies employing melatonin doses in
this range are urgently needed. Since the pharmaceutical industry is refractive
to support them because of the lack of protective patents for a natural
compound, only the involvement of governmental and non-profit organizations can
achieve that goal. Within this prospect, the off-label use of melatonin is
discussed.
Hand, Foot, and Mouth Disease Caused by Coxsackievirus A6: A Preliminary Report from Istanbul
Authors: CEYLAN AYSE N. , TUREL OZDEN , GULTEPE BILGE SUMBUL , INAN ELIF , TURKMEN AYSEL VEHAPOGLU , DOYMAZ MEHMET Z. 
Published: June 2019

Abstract
Hand, foot, and mouth disease (HFMD) is caused by various serotypes of Enterovirus genus. Coxsackievirus A16 (CV-A16) and enterovirus A71 (EV-A71) were known to be the only responsible agents for these epidemics; however, this opinion was challenged after the detection that coxsackievirus A6 (CV-A6) was the responsible species for the outbreak in Finland in 2008. HFMD is frequently seen in Turkey, and no detailed study on its clinical and microbiological epidemiology has previously been reported. The present study addresses this question. Twenty-seven patient samples collected between 2015 and 2017 were included in the study. Typing was conducted by RT-PCR and the sequencing applied directly to patient’s samples and as well as to the viral cultures with pan-enterovirus and serotype-specific primers. The presence of Enterovirus in 12 of 27 HFMD samples was shown with RT-PCR. The causative agent for three of these 12 samples was CV-A16, one of the most frequent two serotypes around the world, and the remaining nine samples was CV-A6. The findings of the study are relevant since it pertains to the molecular epidemiology of HFMD in Turkey, a gateway country where different serotypes might be circulating and transmitted. The findings also support the notion that CV-A6 cases are rising in number, which has caused more severe clinical features and widespread rashes in recent outbreaks.
Evaluation of a Salmonella Strain Isolated from Honeybee Gut as a Potential Live Oral Vaccine Against Lethal Infection of Salmonella Typhimurium
Authors: ZAFAR HASSAN , RAHMAN SAJJAD UR , ALI SULTAN , JAVED MUHAMMAD TARIQ 
Published: June 2019

Abstract
In this research, Salmonella species were isolated from the animal, insect and human enteric sources in Faisalabad, Punjab, Pakistan. These species were characterized by different microbiological and molecular techniques including polymerase chain reaction (PCR) by amplification of the 16S rRNA gene. Furthermore, sequencing of the amplicons confirmed all ten isolates as Salmonella strains. The antigenic cross-reactivity was found maximum between the HB1 (strain isolated from honeybee) antiserum and its antigen with an antibody titer of 1:128, while the HB1 antiserum showed a cross-reactive titer range of 1:8 to 1:64. On the basis of the highest geometric mean titer (GMT) shown by the antiserum of the HB1 antigen, it was selected as the best candidate for a cross-reactive live Salmonella oral antigen. Moreover, the HB1 antigen was used a live oral antigen (1 × 1010 CFU/ml) in a safety test in rabbits and proved to be avirulent. During the animal trial, three different oral doses of the HB1 live oral antigen were evaluated in four different rabbits’ groups (R1, R2, R3, and R4). The dose number 2 of 0.5 ml (two drops orally and repeated after one week) gave the best GMT measured by indirect hemagglutination (IHA) as compared to the other two doses, while R4 group was kept as control. Results of the challenge protection test also validated the efficacy of the double dose of the HB1 live vaccine, which gave the highest survival percentage. Results of this study lay the foundation for a potential cross-reactive live oral Salmonella vaccine that has proved to be immunogenic in rabbits.
Evaluation of The Pathogenic Potential of Insecticidal Serratia marcescens Strains to Humans
Authors: KONECKA EDYTA , MOKRACKA JOANNA , KRZYMIŃSKA SYLWIA , KAZNOWSKI ADAM 
Published: June 2019

Abstract
We observed the death of insect caterpillars of Spodoptera exigua in the laboratory culture line and identified Serratia marcescens as the bacterial causative agent of the insect death. We confirmed that S. marcescens had insecticidal activity against S. exigua and caused high mortality of larvae. The LC50 values of S. marcescens CFU per 1 cm2 of insect diet surface were similar for all isolates. Our research reports novel strains with high pesticidal activity as candidates for future research on a new bioinsecticide. As bioinsecticides cannot be harmful to non-target organisms, we determined the pathogenic properties of S. marcescens to humans. We proved the ability of S. marcescens to damage mammalian epithelial cells. All strains had cytopathic effects to Vero cells with a cytotoxic index ranging from 51.2% ± 3.8% to 79.2% ± 4.1%. We found that all of the strains excreted catecholate siderophore – enterobactin. All isolates were resistant to sulfamethoxazole, tobramycin, gentamicin, cefepime, and aztreonam. We did not observe the ESBL phenotype and the integrons’ integrase genes. Resistance to sulfamethoxazole was due to the presence of the sul1 or sul2 gene. The use of resistant S. marcescens strains that are pathogenic to humans in plant protection may cause infections difficult to cure and lead to the spread of resistance genes. The results of our study emphasize the necessity of determination of the safety to vertebrates of the bacteria that are proposed to serve as biocontrol agents. The novelty of our study lies in the demonstration of the indispensability of the bacteria verification towards the lack of hazardous properties to humans.