scholarly journals ACCOUNTING FOR THE INFLUENCE OF HUMIDITY PROPERTIES OF AUTOCLAVE- CURED CELLULAR CONCRETE IN THE DESIGN AND CONSTRUCTION OF ENCLOSING STRUCTURES

2021 ◽  
pp. 88-99
Author(s):  
Valeriy STROTSKIY ◽  
Aleksey KROKHIN ◽  
Vladimir SAVIN
Keyword(s):  
Frost Resistance ◽  
Pore Space ◽  
Deformation Characteristics ◽  
Solid Ratio ◽  
S Factor ◽  
Negative Temperatures ◽  
Main Factors ◽  
Surface Tension Forces ◽  
The Relationship ◽  
Cellular Concrete

The results of studies of porosity, water absorption, moisture shrinkage and frost resistance of cellular concrete, which are some of the main factors determining the durability of cellular concrete enclosing structures manufactured using autoclave hardening technology, are considered. Methods for determining water absorption, moisture shrinkage and frost resistance are presented. The relationship between the moisture shrinkage and the capillary forces (the sum of the surface tension forces on the micromeniscs of liquid in the capillaries of cellular concrete), as well as the dependence of the shrinkage on the size (radius) of the capillary and gas pores of cellular concreteand on the water-solid ratio (W/S-factor) of cellular concrete, is established. In the field of frost resistance of cellular concrete, the relationship between the structure of the pore space of concrete and its deformation characteristics under the action of negative temperatures is studied. The effect of the presence of gas pores in cellular concrete on the reduction of frost expansion deformations is described.

scholarly journals Some observations considering undrained shear strength, liquidity index, and fluid/solid ratio of mono-mineralic clays with water–ethanol mixtures

2018 ◽  
Vol 55 (7) ◽  
pp. 1048-1053 ◽  
Author(s):  
Giovanni Spagnoli ◽  
Helge Stanjek ◽  
Asuri Sridharan
Keyword(s):  
Pore Space ◽  
Regression Line ◽  
Liquid Limit ◽  
Particle Interactions ◽  
Solid Ratio ◽  
Liquidity Index ◽  
The Impact ◽  
First Time ◽  
The Relationship ◽  
Undrained Shear

The mechanical properties of clays are influenced by the characteristics of the fluid in the pore space. The liquid limit reacts differently to the permittivity, ε, of the fluid: for smectites the slopes are positive, for kaolinite and illite they are negative and smaller. This dissimilarity can be explained by the structural differences between swelling smectites with solvated interlayer cations and nonswelling clay minerals such as kaolinite and illite. Undrained shear strengths, cu, of Ca–smectite, but not Na–smectite, correlate with the actual fluid ratio. Regressing cu against the liquidity index, IL, yields two different regression lines for Na–smectite and Ca–smectite. For the first time it is shown that normalizing cu to the ε of the pore fluid results in a single regression line for both smectitic clay types. As kaolinites and illites possess significantly less exchangeable cations than smectites, this yields significantly smaller ranges for Atterberg limits and reduces the impact of ε on almost pure particle–particle interactions. In addition, the much larger particle sizes of the kaolinite and illite may dominate the undrained shear strengths, as normalization of cu to ε did not change the relationship to either the actual water content or the liquidity index.

scholarly journals Review of the relationship between aggregates geology and Los Angeles and micro-Deval tests

2021 ◽  
Vol 80 (3) ◽  
pp. 1963-1980
Author(s):  
Solomon Adomako ◽  
Christian John Engelsen ◽  
Rein Terje Thorstensen ◽  
Diego Maria Barbieri
Keyword(s):  
Los Angeles ◽  
Crystal Size ◽  
Grain Shape ◽  
Mechanical Performance ◽  
Pore Space ◽  
Construction Material ◽  
Engineering Properties ◽  
Coarse Grained ◽  
The Impact ◽  
The Relationship

AbstractRock aggregates constitute the enormous volume of inert construction material used around the globe. The petrologic description as igneous, sedimentary, and metamorphic types establishes the intrinsic formation pattern of the parent rock. The engineering properties of these rocks vary due to the differences in the transformation process (e.g. hydrothermal deposits) and weathering effect. The two most common mechanical tests used to investigate the performance of aggregates are the Los Angeles (LA) and micro-Deval (MD) tests. This study reviewed the geological parameters (including mineralogy, grain and crystal size, grain shape, and porosity) and the relationship to Los Angeles and micro-Deval tests. It was found that high content of primary minerals in rocks (e.g. quartz and feldspar) is a significant parameter for performance evaluation. Traces of secondary and accessory minerals also affect the performance of rocks, although in many cases it is based on the percentage. Furthermore, some studies showed that the effect of mineralogic composition on mechanical strength is not sufficient to draw final conclusions of mechanical performance; therefore, the impact of other textural characteristics should be considered. The disposition of grain size and crystal size (e.g. as result of lithification) showed that rocks composed of fine-grain textural composition of ≤ 1 mm enhanced fragmentation and wear resistance than medium and coarse grained (≥ 1 mm). The effect of grain shape was based on convex and concave shapes and flat and elongated apexes of tested samples. The equidimensional form descriptor of rocks somehow improved resistance to impact from LA than highly flat and elongated particles. Lastly, the distribution of pore space investigated by means of the saturation method mostly showed moderate (R = 0.50) to strong (R = 0.90) and positive correlations to LA and MD tests.

Effects of surface tension and viscosity on airway reopening

1990 ◽  
Vol 69 (1) ◽  
pp. 74-85 ◽  
Author(s):  
D. P. Gaver ◽  
R. W. Samsel ◽  
J. Solway
Keyword(s):  
Surface Tension ◽  
Fluid Viscosity ◽  
Opening Pressure ◽  
Viscous Forces ◽  
Considerable Portion ◽  
Airway Opening ◽  
Wall Compliance ◽  
Large Opening ◽  
Surface Tension Forces ◽  
The Relationship

We studied airway opening in a benchtop model intended to mimic bronchial walls held in apposition by airway lining fluid. We measured the relationship between the airway opening velocity (U) and the applied airway opening pressure in thin-walled polyethylene tubes of different radii (R) using lining fluids of different surface tensions (gamma) and viscosities (mu). Axial wall tension (T) was applied to modify the apparent wall compliance characteristics, and the lining film thickness (H) was varied. Increasing mu or gamma or decreasing R or T led to an increase in the airway opening pressures. The effect of H depended on T: when T was small, opening pressures increased slightly as H was decreased; when T was large, opening pressure was independent of H. Using dimensional analysis, we found that the relative importance of viscous and surface tension forces depends on the capillary number (Ca = microU/gamma). When Ca is small, the opening pressure is approximately 8 gamma/R and acts as an apparent “yield pressure” that must be exceeded before airway opening can begin. When Ca is large (Ca greater than 0.5), viscous forces add appreciably to the overall opening pressures. Based on these results, predictions of airway opening times suggest that airway closure can persist through a considerable portion of inspiration when lining fluid viscosity or surface tension are elevated.

Intelligence Selection System for Honing Parameter Based on Genetics and Artificial Neural Networks

2010 ◽  
Vol 102-104 ◽  
pp. 846-850
Author(s):  
Wen Yu Pu ◽  
Yan Nian Rui ◽  
Lian Sheng Zhao ◽  
Chun Yan Zhang
Keyword(s):  
Neural Networks ◽  
Artificial Neural Networks ◽  
Selection System ◽  
Process Data ◽  
Replacement Strategy ◽  
Machining Quality ◽  
Main Factors ◽  
Artificial Neural ◽  
Neural Networks Optimization ◽  
The Relationship

Appropriate selecting of process parameters influences the machining quality greatly. For honing, the main factors are product precision, material components and productivity. In view of this situation, a intelligence selection model for honing parameter based on genetics and artificial neural networks was built by using excellent robustness, fault-tolerance of artificial neural networks optimization process and excellent self-optimum of genetic algorithm. It can simulate the decision making progress of experienced operators, abstract the relationship from process data and machining incidence, realize the purpose of intelligence selection honing parameter through copying, exchanging, aberrance, replacement strategy and neural networks training. Besides, experiment was performed and the results helped optimize the theories model. Both the theory and experiment show the updated level and feasibility of this system.

scholarly journals Leadership Style, Compensation And Its Effect On Employee Performance (PT. SSBP Case)

2020 ◽  
Vol 18 (3) ◽  
pp. 138
Author(s):  
Elly Alfrida ◽  
Petrus T. Resi ◽  
Sabam Simbolon
Keyword(s):  
Leadership Style ◽  
Employee Performance ◽  
Independent Variables ◽  
Main Factors ◽  
Relationship Of ◽  
The Relationship ◽  
A Company ◽  
Two Independent Variables

This research is aimed at understanding the relationship of leadership style and compensation on employee performance at PT SSBP considering that the two independent variables are the main factors that determines the success of a company as general as well as PT SSBP. The research obtained data from 144 respondents out of 210 total employees. A questionnaire was prepared to catch their perception on leadership style and compensation and how they affect their performance in the company they work with. From the data obtained and the analysis result shows that the relationship and the contribution of leadership style and compensation on the performance of employees is strong and significant, either partially or simultaneously. Therefore as managerial instruments, leadership style and compensation are extremely important factors to be considered and continuously updated in order to keep and maintain employees motivation that in turn will boost their performance,

scholarly journals SUSTAINABILITY OF NUTS OF THE GENUS JUGLANS TO NEGATIVE WINTER TEMPERATURES IN THE VORONEZH REGION

2018 ◽  
Vol 8 (1) ◽  
pp. 72-80 ◽  
Author(s):  
В. Славский ◽  
V. Slavskiy ◽  
Михаил Чернышов ◽  
Mikhail Chernyshov
Keyword(s):  
Frost Resistance ◽  
The North ◽  
Winter Temperatures ◽  
Negative Temperatures ◽  
Voronezh Region ◽  
Stable Forms

Given the high value of Juglans nuts, the increase in their production should not only be due to the identification and breeding of the best forms, but also by shifting the established border of cultivation to the North. In this regard, the main purpose of the work is to study and analyze the adaptive characteristics of plants in winter. The paper considers garden, park and field protection plantations, plantations, landscape groups and stand-alone trees of Juglans family nuts on adaptive signs of frost resistance and frost stability, as well as the most stable forms, which should form the basis of the breeding fund. Comparison of resistance of the genus Juglans to the various factors of ethnology gives the following results: decreasing resistance to low negative temperatures, plants can be placed as J. cenerea, J. manshurica, J. nigra, J. cordiformis, J. regia.

scholarly journals THE ROLE OF THE RELATIONSHIP WITH THE MOTHER IN CHILDHOOD IN FORMING A WOMAN'S ATTITUDE TOWARDS HER OWN MOTHERHOOD

2020 ◽  
Vol 11 (87) ◽  
Author(s):  
Tatiana Sidorenko ◽  
◽  
Natalia Grisenko ◽  
Keyword(s):  
Theoretical Analysis ◽  
Adult Age ◽  
Personal Attitude ◽  
Psychological Science ◽  
Factors Influencing ◽  
Different Types ◽  
Main Factors ◽  
Psychological Features ◽  
The Relationship

The article is devoted to the study of such an important psychological phenomenon as an attitude of women to their own motherhood. It is summarizes the study of the problem of motherhood in psychological science in general. The article analyzes the problem of the influence of the relationship with the mother in childhood on the formation of a woman's attitude to her own motherhood in adult age. It is illuminates views of foreign and national researchers on the study of this phenomenon, as well as the essence of different areas of research on this phenomenon. Based on the theoretical analysis of the literature on this topic, the concept of "motherhood", its content and psychological essence is studied. Cultural-historical, biological, physiological and psychological aspects to the study of motherhood are singled out. The main content of scientific views on the formation of the phenomenon of motherhood is generalized. The main factors influencing the development of a woman's maternal sphere and the formation of the attitude to one's own motherhood are analyzed and considered. The content of such basic concepts as "mother's image" and "maternal relations" is revealed. The psychological features of the formation of an adequate image of the mother in the theoretical analysis of the ontogenesis of the maternal sphere are analyzed. The article also reveals the dynamics of motherhood in ontogenesis. The types of maternal relations and their role in the life of a mature woman are determined, as well as the influence of these relations on the formation of a woman's attitude to her own motherhood. The influence of different types of relationships between women and their own mothers on the level of formation of their attitude to personal motherhood has been empirically studied. Two groups of women were studied, one group had a positive relationship with their own mother, and the other had a negative one. In the course of the research the differences between different types of maternal relations and the level of formation of a woman's personal attitude to motherhood are singled out.

scholarly journals Study on the Influence of Urban Spatial Connection of Beijing Tianjin Hebei Urban Agglomeration on Total factor Productivity

2020 ◽  
Vol 206 ◽  
pp. 02010
Author(s):  
Wang Hongmei ◽  
Lu Zhihui
Keyword(s):  
Industrial Structure ◽  
Network Centrality ◽  
Connection Strength ◽  
External Effect ◽  
Factor Productivity ◽  
Positive Role ◽  
Centrality Index ◽  
Main Factors ◽  
City Cluster ◽  
The Relationship

The development of a city can not be separated from the connection with the outside world. A city can benefit from the external effect of the connection network with other cities. This paper studies the relationship between cities’ connection strength and TFP according to the network centrality index, which measures the level of the connection between cities. It is found that the connection between cities has a significant positive role in promoting the TFP of cities in a city cluster. The differences of labor scale, industrial structure and openness are the main factors that affect the connection between cities.

scholarly journals Nitrous oxide emission from conservation forest of Kampar Peninsula peatland ecosystem

2021 ◽  
Vol 11 (3) ◽  
pp. 442-452
Author(s):  
Nardi ◽  
Syaiful Anwar ◽  
Mohamad Yani ◽  
Nurholis ◽  
Muhammad Hendrizal
Keyword(s):  
Nitrous Oxide ◽  
Pore Space ◽  
Chemical Properties ◽  
N2o Emission ◽  
Data Availability ◽  
Physical And Chemical Properties ◽  
Swamp Forest ◽  
Main Factors ◽  
Physical And Chemical ◽  
And Chemical Properties

Nitrous oxide (N2O) is a long-lived greenhouse gas with a warming potential of 300 times higher than CO2. Conserving of intact peat swamp forest can hold the natural physical and chemical properties of the soil, such that the N2O emission occurs naturally. To quantify N2O emission from peatland ecosystems, data availability is highly needed. The objectives of this study were to quantify the emission of N2O and determine the main factors controlling N2O emission from peatland conservation forests. This research was conducted from January to December 2020 in the Kampar Peninsula, Pelalawan Regency, Riau Province. This study found that N2O emission at peatland conservation forest was 0.23 ± 0.19 kg-N/ha/year. Substantial changes in soil and environmental factors such as water table, soil temperature, soil moisture, water-filled pore space, NH4-N, and NO3-N significantly affect the exchange of N2O between peatlands and the atmosphere.

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