Comparison and Application of Two Mathematical Models in Predicting and Determining the State of Deposition and Slagging of Coal Burning Boiler

2013 ◽  
Vol 818 ◽  
pp. 240-245
Author(s):  
Xiao Qiang Wen
Keyword(s):  
Power Plant ◽  
Softening Temperature ◽  
The State ◽  
Vague Sets ◽  
Coal Burning ◽  
Average Temperature ◽  
Acid Ratio ◽  
Normal Method ◽  
High Level ◽  
Temperature Furnace

Building a model to predict the state of slag on coal-fired boilers is a good way to optimize the coal combustion and reduce the risk of boiler slag. This paper built new models based on vague sets to predict the state of slag on coal-fired boilers, in which there were six input vectors, which were softening temperature, SiO2-Al2O3 ratio, alkali-acid ratio, percentage of silicon content, the dimensionless average temperature furnace and the dimensionless inscribed circle diameter furnace, and one output vectors, which was slagging degree. Two methods, which were based on the sense of distance and symmetric fuzzy cross entropy, were proposed to calculate the similarity between vague sets. 10 coal burning boilers were selected as known samples and the feasibility of the new methods was proved by the result of predicting the state of slag on the four coal burning boilers from Jilin heat and power plant, Xinli power plant, Jinzhou power plant and Qinhuangdao power plant. Through predicting and determining, it proves that the two pattern recognition models are high in prediction accuracy. Compared with the normal method, it is easier for operators to predict, determine the slagging state and reduce disturbance as far as possible. Besides, a prediction system has been developed by object-oriented high-level language accordingly.

Prediction of the Slagging Characteristics of Coal Ash Based on Symmetric Fuzzy Cross Entropy and Vague Sets

2013 ◽  
Vol 302 ◽  
pp. 617-621
Author(s):  
Xiao Qiang Wen
Keyword(s):  
Pattern Recognition ◽  
Prediction Model ◽  
Coal Ash ◽  
Softening Temperature ◽  
Cross Entropy ◽  
Accuracy Rate ◽  
Recognition Model ◽  
Vague Sets ◽  
Acid Ratio ◽  
Sets Theory

A prediction model was built to predict the slagging characteristics of coal ash based on the theory of symmetric fuzzy cross entropy and vague sets. Softening temperature, SiO2-Al2O3 ratio, Alkali-acid ratio, silicon percentage of value were selected as input vectors. Firstly, the vague values of the selected samples were calculated based on vague sets theory, and then the similarity degree was evaluated based on symmetric fuzzy cross entropy. The prediction results prove that the predicting accuracy rate of the new pattern recognition model is 90%. So, the model built here is reasonable and feasible and meets the requirement of engineering.

Multidimensional analysis of the state of Russian studies on the education issues over 1993–2016

2018 ◽  
pp. 50-62
Author(s):  
Дмитрий Рубвальтер ◽  
Dmitry Rubvalter ◽  
Александр Либкинд ◽  
Alexander Libkind ◽  
Валентина Маркусова ◽  
...  
Keyword(s):  
Web Of Science ◽  
The State ◽  
Multidimensional Analysis ◽  
Russian Regions ◽  
Global Flow ◽  
Educational Issues ◽  
Foreign Countries ◽  
High Level ◽  
The Web ◽  
Made In

A multidimensional analysis of the state of Russian studies on the education issues over 1993–2016 was carried out based on the materials of the data contained in the Web of Science (SSCI, A & HCI and SCI-E databases). There were determined the dynamics and trends of a number of relevant indicators, such as the number of Russian publications by year, the share of these publications in the global flow of publications on education issues, the dynamics of the share of publications made in co-authorship with foreign colleagues, etc. A number of distributions of Russian publications on educational issues was compiled and analyzed: by journals, by Russian regions and cities, by organizations and authors of the publications. It was found that most of these distributions were characterized by a high level of non-uniformity. A list of journals (125 titles) in which Russian works on education issues had been published was compiled. Russian organizations (308) and domestic researchers (about two thousand) engaged in studying the issues of education were identified. It was discovered that more than 200 organizations and about 400 academicians from 60 foreign countries had participated in Russian studies on the education issues.

Measurement of the Pulverized Coal Concentration by Measuring the Time Delay of Ultrasonic with Digital Correlation Method

2013 ◽  
Vol 333-335 ◽  
pp. 359-364
Author(s):  
Ke Wang
Keyword(s):  
Time Delay ◽  
Power Plant ◽  
Correlation Method ◽  
The State ◽  
Pulverized Coal ◽  
Measuring System ◽  
Digital Correlation ◽  
Coal Boiler ◽  
Key Parameter

The pulverized coal concentration in blast pipe in front of firebox is one key parameter in coal boiler used in a power plant; it will affect the state of burning in firebox. This paper proposes a new digital correlation method to measure the time delay of ultrasonic for measuring the pulverized coal concentration. The principle of measurement is discussed in detail and the measuring system is designed.

scholarly journals Courage and Cowardice in the North African Campaign: The Eighth Army and Defeat in the Summer of 1942

2013 ◽  
Vol 20 (1) ◽  
pp. 99-122 ◽  
Author(s):  
Jonathan Fennell
Keyword(s):  
North Africa ◽  
The State ◽  
The Other ◽  
Human Dimension ◽  
North African ◽  
The North ◽  
High Level ◽  
Eighth Army

High rates of desertion and surrender during the battles in North Africa in the summer of 1942 were a major factor in Eighth Army’s poor combat performance. At the time, some suggested that these problems were symptomatic of a lack of courage or even of cowardice. There are two broad strands to the conceptualization of courage and cowardice. One focuses on the willingness of the person to fight; the other puts emphasis on how actions express an individual’s ability to cope with fear. Whichever conceptualization is used, high morale motivates the soldier to fight and shields the ordinary recruit from his fear, preventing it from overcoming him in battle. Where morale fails, the soldier is left demotivated and burdened with his terror and, therefore, and is therefore prone to desertion or surrender. Because it is extremely difficult to maintain morale at a continuously high level in an environment governed by chance and managed by humans, all soldiers can find themselves in situations where their actions may be judged as cowardly. Alternatively, if they are properly motivated to fight and prepared by the state and military to deal with the unavoidable fear of combat, all soldiers can be labelled courageous. Accordingly, emotive terms should be avoided when attempting to describe rationally explainable outcomes. The undoubtedly negative connotations attached to cowardice in battle and the positive ones attached to courage are, therefore, arguably unhelpful in understanding Eighth Army’s performance in the summer of 1942 and the human dimension in warfare more generally.

Analysis of the state of the migration process of the ukrainian population in the context of domestic and international levels

2021 ◽  
Vol 72 (5) ◽  
pp. 110-118
Author(s):  
M. Shkurat ◽  
K. Pavlotska
Keyword(s):  
Social Protection ◽  
Negative Impact ◽  
Migration Policy ◽  
Cash Flows ◽  
The State ◽  
Negative Consequences ◽  
Migration Process ◽  
State Of The Economy ◽  
Migration Flows ◽  
High Level

Analysis of the migration process of the Ukrainian population, which takes place within the state and at the international level during 2014–2019 is carried out in this paper. On the basis of scientific works of domestic scientists and institutes the problems which have not been investigated, and also aspects which have been solved partially are defined. The negative consequences of the Ukrainian migration process on the state of the country are identified. The classification of migration flows of the Ukrainian population according to the reasons of movement is carried out. The main regions and countries which, as of the beginning of 2021, are more attractive to compatriots and are characterized by significant influxes of Ukrainians are identified. The main centers of departure – regions and countries – which are characterized by high level of outflow of Ukrainians are determined, the main problems and reasons that motivate the outflow of Ukrainians are highlighted in this paper. The level of growth of the Ukrainian population in terms of migration flows is defined. The investigation of Ukrainian diasporas, territorial location and analysis of their share in comparison is carried out. The main factors that force the Ukrainian population to move, which affects the demographic situation in Ukraine, the level of employment, as well as the amount of cash flows to the country and the state of the economy as a whole are identified. The main regulations and identified solutions to the migration flows of the domestic population, which were approved and implemented in the period from 2001 to 2019 are compared in this paper. On the basis of current and newly introduced strategies, critical analysis of the ways of regulating the migration process of the Ukrainian population is carried out, the main aspects and problems of the implemented migration policy of Ukraine are determined. The results of the work are to identify the main ways to reduce the negative impact of the migration process on the country's economy and related processes, and strategies to benefit from the movement of citizens of Ukraine, namely: introduction of intellectual security, revision of wages by region, stimulating the process of attracting technology in all spheres of activity and formation of the social protection system.

Can Russia Fight Organized Crime and Corruption?

2002 ◽  
Vol 23 (2) ◽  
pp. 37-55
Author(s):  
Louise I. Shelley
Keyword(s):  
Organized Crime ◽  
Local Level ◽  
The State ◽  
The Political ◽  
Political Will ◽  
Structural Problems ◽  
Economic Elite ◽  
High Level ◽  
Personal Interests

The murder of Valentin Tsvetkov, the governor of Magadan in central Moscow in broad day light in October 2002 highlights that organized crime and corruption are still alive and well and highly destructive of life and governance in Russia (Wines, 2002). His murder once again raises the question, “Why has Russia not been able to stop organized crime and high level corruption?” The answer is that Russia docs not have the political will at the national, regional or local level to fight these problems. This is true because the Kremlin and economic elite push their personal interests over those of the state and the society. Structural problems such as low salaries of state personnel and the embedding of organized crime and corruption make reform very difficult.

The Effect of Post-Irradiation Annealing on VVER-440 RPV Materials Mechanolocal Properties and Nano-Structure Under Re-Irradiation

2009 ◽  
Author(s):  
S. Rogozkin ◽  
A. Chernobaeva ◽  
A. Aleev ◽  
A. Nikitin ◽  
A. Zaluzhnyi ◽  
...  
Keyword(s):  
Transition Temperature ◽  
Power Plant ◽  
Atom Probe Tomography ◽  
Nuclear Power ◽  
Temperature Shift ◽  
Atom Probe ◽  
Structure Evolution ◽  
Nano Structure ◽  
High Level ◽  
Nuclear Power Plant Unit

The present work provides the analyses of embrittlement behavior and atom probe tomography study of nano-structure evolution of VVER-440 RPV materials under irradiation and re-irradiation. Specimens from VVER-440 weld with high level of cupper (0.16 wt.%) and phosphorus (0.027–0.038 wt.%) were irradiated in surveillance channels of Rovno Nuclear Power plant unit 1 (Ro-1). The embrittlement behavior has been assessed by transition temperature shift.

scholarly journals Technological exchanged natural radioactivity in vicinity of the Coal Burning Power Plant Kakanj, BiH

2009 ◽  
Vol 44 (5) ◽  
pp. 759-764
Author(s):  
D. Samek ◽  
L. Saracevic ◽  
N. Gradascevic ◽  
A. Mihalj
Keyword(s):  
Power Plant ◽  
Natural Radioactivity ◽  
Coal Burning

Optimal State-Space Control of a Gas Turbine Engine

1992 ◽  
Vol 114 (4) ◽  
pp. 763-767 ◽  
Author(s):  
J. W. Watts ◽  
T. E. Dwan ◽  
C. G. Brockus
Keyword(s):  
State Space ◽  
Gas Turbine ◽  
State Space Model ◽  
Gas Turbine Engine ◽  
The State ◽  
Operating Conditions ◽  
Turbine Engine ◽  
Analog Control ◽  
Linear State ◽  
High Level

An analog fuel control for a gas turbine engine was compared with several state-space derived fuel controls. A single-spool, simple cycle gas turbine engine was modeled using ACSL (high level simulation language based on FORTRAN). The model included an analog fuel control representative of existing commercial fuel controls. The ACSL model was stripped of nonessential states to produce an eight-state linear state-space model of the engine. The A, B, and C matrices, derived from rated operating conditions, were used to obtain feedback control gains by the following methods: (1) state feedback; (2) LQR theory; (3) Bellman method; and (4) polygonal search. An off-load transient followed by an on-load transient was run for each of these fuel controls. The transient curves obtained were used to compare the state-space fuel controls with the analog fuel control. The state-space fuel controls did better than the analog control.

scholarly journals (M.A. thesis) Migration schedules by age and characterization of migrants in the micro-regions of Goiás and the Federal District, 1975–1979 and 1986–1990

2018 ◽  
Author(s):  
Ernesto F. L. Amaral
Keyword(s):  
Low Income ◽  
Rural Areas ◽  
Federal District ◽  
The State ◽  
Considerable Proportion ◽  
Migrant Population ◽  
Formal Sector ◽  
Mato Grosso ◽  
The North ◽  
High Level

Title in Portuguese: Funções de migração por idade e caracterização de migrantes das microrregiões de Goiás e Distrito Federal, 1975-1979 e 1986-1990(Dissertação de Mestrado)(M.A. Thesis)Since the 70’s, the Brazilian Middle-West Region has experienced an important modernization process in agricultural and industrial activities, which has led to an employment retraction and migration flows, especially from rural areas to the major metropolitan cities of the region. In this research the focus of analysis are the State of Goiás and the Federal District, which encompasses Brasília, the capital of Brazil. In order to understand the new population configuration, the region was divided into four sub-areas (micro-region of Goiânia, micro-region of Entorno de Brasília, the Federal District, and a group of 16 micro-regions of Goiás) and the patterns of migration, by age and sex, were estimated for the periods 1975-1979 and 1986-1991. In addition, differences between native and migrant population of each sub-area, according to the participation in the labor force, income, education and type of migration were investigated. The analysis was performed on the basis of the 1980 and 1991 Brazilian Census data.In the intra-state migration, the fluxes between the micro-region of Goiânia and the 16 other micro-regions of Goiás, and between the Federal District and the micro-region of Entorno de Brasília were the most important. In the inter-state migration, the flux from the states of Mato Grosso, Mato Grosso do Sul and the North region to the 16 micro-regions of Goiás, as well as the flux from Northeast, Southeast and South to the Federal District were significant. But there was a decline in the migration to the Federal District, between 1975-1979 and 1986-1991, while, in the same period, the migration to the Entorno of Brasília increased.The chance of the migrant population in the micro-region of Goiânia and in the Federal District to have worked in the last 12 months prior to census interview was lower than that of the native population. However, those who migrated from the Federal District to the micro-region of Entorno de Brasília had higher chance to have worked in the formal sector than those who did not migrate. Migrants who moved from the micro-region of Entorno de Brasília and the 16 other micro-regions of Goiás to the micro-region of Goiânia had lower wages than the non-migrant population. The lowest level of wages was recorded for the migrants to the 16 other micro-regions of Goiás. Migrants living in the Federal District had high level of education, while those migrants living in the micro-region of Entorno de Brasília had low level of education.In 1986-1990, the micro-regions of Goiânia and Entorno de Brasília, as well as the 16 other micro-regions of Goiás, presented a high percentage of returned migrants. In the same period, a major proportion of migrants to the micro-region of Entorno de Brasília had first moved from Southeast or from the Federal District to others regions. In addition, there was a considerable proportion of migrants with low income who had moved from Northeast to the Federal District and then to the micro-region of the Entorno de Brasília.Future research could focus other areas or regions of Brazil, and could also explore the same kind of analysis, on the basis of the incoming 2000 Brazilian Census, which requires the development of new techniques, as it did not collect information on the city of previous residence, but only on the state of residence.

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