Structural System and Conceptual Model Test of Solar Chimney

2010 ◽  
Vol 168-170 ◽  
pp. 1601-1610 ◽  
Author(s):  
Xing Qiang Zhang ◽  
Xing Fei Yuan ◽  
Li Min Li

The solar chimney power station is a renewable energy system consisting of solar collector, wind turbine, and chimney. To improve the efficiency of energy generation, the higher chimney is the better. Considering the difference between the solar chimney and the traditional high-rise structure, the study on the chimney from the structural point of view is produced in this paper. The existing and planed chimneys are first introduced. Then the solar chimney is classified according to material, structural system, and constraint condition. Followed that, application of prestress technology including adoption of prestressed concrete, introduction of circumferential prestress, arrangement of stayed cable or cable net, and utilization of tensegrity system in the solar chimney is involved, which can improve the structural behavior of the chimney significantly. On this basis, conceptual models of three different structural systems are designed, and the performance of the models is tested under the horizontal force to show the effect of stayed cable and spokewise cable.

2021 ◽  
Vol 9 (2) ◽  
Author(s):  
Tünde Szabó

We often find the Soviet past at the core of Lyudmila Ulitskaya’s works, and most critics agree that the description of everyday life and historicity are fundamental principles of her prose. Nonetheless, episodes which record the characters’ mystical experiences play a fairly significant part in Ulitskaya’s works. However, they receive considerably less attention in research on her oeuvre. In this paper, the author focuses on the mystical component of Ulitskaya’s novels and most recent short stories and attempts to define the thematic and structural characteristics of the mystical episodes. In the first part of the paper, the author reviews the constant elements of the characters’ mystical experiences in different works. These experiences are primarily connected with encountering death and are based on the character’s borderline position and the permeability of the frontier between “reality” and the afterworld. This frontier is marked out by recurrent motifs, which symbolically bestow upon death the meaning of transformation (transubstantiation) and revival. From a structural point of view, the delineation of the frontier between the two worlds can be explained, among others, through the characteristics of fantasy. In the second part of the paper, the article examines this aspect of the mystical episodes of Ulitskaya’s works with reference to Tzvetan Todorov’s concept, which defines the fantastical as an interim phenomenon between the “uncanny” and the “miraculous”. The characters’ mystical experiences in the episodes examined here receive a rational explanation (dream, hallucination before dying, psychological disorder), which cancels their fantastic nature. As a result of this duality of a rational explanation and the simultaneous uncertainty about judging the experience, the mystical episodes of Ulitskaya’s works can be categorised as “fantastical and uncanny”. When these episodes are examined from the point of view of the properties of the genuinely mystical texts, we find a “profane mysticism”, primarily as a result of the neutrality of the narrator’s discourse, the blurriness of the difference between what is real and what is supernatural, and the proximity of the narrator’s and the author’s positions.


1997 ◽  
Vol 2 (3) ◽  
pp. 226-234 ◽  
Author(s):  
Michel Cabanac ◽  
Chantal Pouliot ◽  
James Everett

Previous work has shown that sensory pleasure is both the motor and the sign of optimal behaviors aimed at physiological ends. From an evolutionary psychology point of view it may be postulated that mental pleasure evolved from sensory pleasure. Accordingly, the present work tested empirically the hypothesis that pleasure signals efficacious mental activity. In Experiment 1, ten subjects played video-golf on a Macintosh computer. After each hole they were invited to rate their pleasure or displeasure on a magnitude estimation scale. Their ratings of pleasure correlated negatively with the difference par minus performance, i.e., the better the performance the greater the pleasure reported. In Experiments 2 and 3, the pleasure of reading poems was correlated with comprehension, both rated by two groups of subjects, science students and arts students. In the majority of science students pleasure was significantly correlated with comprehension. Only one arts student showed this relationship; this result suggests that the proposed relationship between pleasure and cognitive efficiency is not tautological. Globally, the results support the hypothesis that pleasure is aroused by the same mechanisms, and follows the same laws, in physiological and cognitive mental tasks and also leads to the optimization of performance.


The results of experimental studies of masonry on the action of dynamic and static (short-term and long-term) loads are presented. The possibility of plastic deformations in the masonry is analyzed for different types of force effects. The falsity of the proposed approach to the estimation of the coefficient of plasticity of masonry, taking into account the ratio of elastic and total deformations of the masonry is noted. The study of the works of Soviet scientists revealed that the masonry under the action of seismic loads refers to brittle materials in the complete absence of plastic properties in it in the process of instantaneous application of forces. For the cases of uniaxial and plane stress states of the masonry, data on the coefficient of plasticity obtained from the experiment are presented. On the basis of experimental studies the influence of the strength of the so-called base materials (brick, mortar) on the bearing capacity of the masonry, regardless of the nature of the application of forces and the type of its stress state, is noted. The analysis of works of prof. S. V. Polyakov makes it possible to draw a conclusion that at the long application of the load, characteristic for the masonry are not plastic deformations, but creep deformations. It is shown that the proposals of some authors on the need to reduce the level of adhesion of the mortar to the brick for the masonry erected in earthquake-prone regions in order to improve its plastic properties are erroneous both from the structural point of view and from the point of view of ensuring the seismic resistance of structures. It is noted that the proposal to assess the plasticity of the masonry of ceramic brick walls and large-format ceramic stone with a voidness of more than 20% is incorrect, and does not meet the work of the masonry of hollow material. On the basis of the analysis of a large number of research works it is concluded about the fragile work of masonry.


2020 ◽  
Vol 7 (2) ◽  
pp. 34-41
Author(s):  
VLADIMIR NIKONOV ◽  
◽  
ANTON ZOBOV ◽  

The construction and selection of a suitable bijective function, that is, substitution, is now becoming an important applied task, particularly for building block encryption systems. Many articles have suggested using different approaches to determining the quality of substitution, but most of them are highly computationally complex. The solution of this problem will significantly expand the range of methods for constructing and analyzing scheme in information protection systems. The purpose of research is to find easily measurable characteristics of substitutions, allowing to evaluate their quality, and also measures of the proximity of a particular substitutions to a random one, or its distance from it. For this purpose, several characteristics were proposed in this work: difference and polynomial, and their mathematical expectation was found, as well as variance for the difference characteristic. This allows us to make a conclusion about its quality by comparing the result of calculating the characteristic for a particular substitution with the calculated mathematical expectation. From a computational point of view, the thesises of the article are of exceptional interest due to the simplicity of the algorithm for quantifying the quality of bijective function substitutions. By its nature, the operation of calculating the difference characteristic carries out a simple summation of integer terms in a fixed and small range. Such an operation, both in the modern and in the prospective element base, is embedded in the logic of a wide range of functional elements, especially when implementing computational actions in the optical range, or on other carriers related to the field of nanotechnology.


Author(s):  
Angela Dranishnikova

In the article, the author reflects the existing problems of the fight against corruption in the Russian Federation. He focuses on the opacity of the work of state bodies, leading to an increase in bribery and corruption. The topic we have chosen is socially exciting in our days, since its significance is growing on a large scale at all levels of the investigated aspect of our modern life. Democratic institutions are being jeopardized, the difference in the position of social strata of society in society’s access to material goods is growing, and the state of society is suffering from the moral point of view, citizens are losing confidence in the government, and in the top officials of the state.


2020 ◽  
Vol 15 (1) ◽  
pp. 39
Author(s):  
С. И. Дудник ◽  
И. Д. Осипов

The article discusses the problems of evolution and the formation of the ideology of an enlightened monarchy in Russia. In this regard, the philosophical and political ideas of Catherine the Great, as well as their theoretical and ideological premises, are analyzed. It is noted that the philosophy of education in Russia was closely connected with the concepts of Voltaire, Didro, Montesquieu, Beccaria, Bentham, their views on natural law and human freedom, humanism and the rule of law. These concepts in the philosophy of Catherine received a specific interpretation, due to the sociocultural conditions of Russia. This was manifested in the famous work of Catherine the Great “The Nakaz”, which recognized Montesquieu's argument in favor of the autocracy, but at the same time, his point of view on the separation of powers was rejected. The specificity of the doctrine of enlightened monarchy lies in the combination of liberal and conservative values, which form eclectic forms. This was the dialectic of the supreme power, the difference between the enlightened monarchy and the ideology of absolutism. The article also notes that education in Russia is associated with fundamental socio-political reforms, processes of secularization of culture. At this time, the natural and human sciences are developing. The changes positively influenced the development of medicine, beautification of towns and public education. Also considered are the views on the autocracy of the opposition nobility intelligentsia: A. N. Radishchev and noted that his criticism of the autocracy was determined by an alternative cultural policy, proceeding from the protection of the interests of the people. The doctrine of enlightened monarchy is characterized by internal worldview inconsistency and political inconsistency, which did not allow solving the pressing social problems of the establishment of legal state, democratization of society and the abolition of serfdom.


2020 ◽  
Vol 15 (1-3) ◽  
pp. 44-59
Author(s):  
Lidia Peneva

Crimes against marriage and family are a particular group of social relation­ships that the law has defended properly in view of the high public significance and value they enjoy. At the moment they are regulated in Chapter VI, Section I, of the specific part of the Penal Code the Repub­lic of Bulgaria. The subject matter of this Statement will, however, be the legisla­tive provisions concerning these criminal­ized acts in retrospect. The purpose of the study is to show by historical method and through the comparatively legal method the development of these criminal groups during the periods of various criminal laws in Bulgaria. This will also provide a basis for reflection on possible de lege ferenda proposals. This report from a structural point of view will be divided into three distinct points, marking each of the penal laws in the Republic of Bulgaria, which were in force before 1968.


Dreyfus argues that there is a basic methodological difference between the natural sciences and the social sciences, a difference that derives from the different goals and practices of each. He goes on to argue that being a realist about natural entities is compatible with pluralism or, as he calls it, “plural realism.” If intelligibility is always grounded in our practices, Dreyfus points out, then there is no point of view from which one can ask about or provide an answer to the one true nature of ultimate reality. But that is consistent with believing that the natural sciences can still reveal the way the world is independent of our theories and practices.


Encyclopedia ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 409-422
Author(s):  
Haihua Zhang ◽  
Yao Tao ◽  
Long Shi

A solar chimney is a renewable energy system used to enhance the natural ventilation in a building based on solar and wind energy. It is one of the most representative solar-assisted passive ventilation systems attached to the building envelope. It performs exceptionally in enhancing natural ventilation and improving thermal comfort under certain climate conditions. The ventilation enhancement of solar chimneys has been widely studied numerically and experimentally. The assessment of solar chimney systems based on buoyancy ventilation relies heavily on the natural environment, experimental environment, and performance prediction methods, bringing great difficulties to quantitative analysis and parameterization research. With the increase in volume and complexity of modern building structures, current studies of solar chimneys have not yet obtained a unified design strategy and corresponding guidance. Meanwhile, combining a solar chimney with other passive ventilation systems has attracted much attention. The solar chimney-based integrated passive-assisted ventilation systems prolong the service life of an independent system and strengthen the ventilation ability for indoor cooling and heating. However, the progress is still slow regarding expanded applications and related research of solar chimneys in large volume and multi-layer buildings, and contradictory conclusions appear due to the inherent complexity of the system.


Membranes ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 429
Author(s):  
Aurelia Cristina Nechifor ◽  
Andreia Pîrțac ◽  
Paul Constantin Albu ◽  
Alexandra Raluca Grosu ◽  
Florina Dumitru ◽  
...  

The separation, concentration and transport of the amino acids through membranes have been continuously developed due to the multitude of interest amino acids of interest and the sources from which they must be recovered. At the same time, the types of membranes used in the sepa-ration of the amino acids are the most diverse: liquids, ion exchangers, inorganic, polymeric or composites. This paper addresses the recuperative separation of three amino acids (alanine, phe-nylalanine, and methionine) using membranes from cellulosic derivatives in polypropylene ma-trix. The microfiltration membranes (polypropylene hollow fibers) were impregnated with solu-tions of some cellulosic derivatives: cellulose acetate, 2-hydroxyethyl-cellulose, methyl 2-hydroxyethyl-celluloseand sodium carboxymethyl-cellulose. The obtained membranes were characterized in terms of the separation performance of the amino acids considered (retention, flux, and selectivity) and from a morphological and structural point of view: scanning electron microscopy (SEM), high resolution SEM (HR-SEM), Fourier transform infrared spectroscopy (FT-IR), energy dispersive spectroscopy (EDS) and thermal gravimetric analyzer (TGA). The re-sults obtained show that phenylalanine has the highest fluxes through all four types of mem-branes, followed by methionine and alanine. Of the four kinds of membrane, the most suitable for recuperative separation of the considered amino acids are those based on cellulose acetate and methyl 2-hydroxyethyl-cellulose.


Sign in / Sign up

Export Citation Format

Share Document