scholarly journals Innovations in Ornamental Culture as a Process of Loss of the Sacred (on the Example of Russian Textile Ornament of the XVIII — Early XX Centuries)

2021 ◽  
Vol 27 (4) ◽  
pp. 139-148
Author(s):  
T. L. Shcherbakova ◽  
Keyword(s):  
Point Of View ◽  
Cultural Significance ◽  
The Stability

The article examines the process of interaction between tradition and innovation in the culture of textile ornament. The stability of the tradition of ornamental elements is investigated from the point of view of the ontology of an archaic society, its inextricable connection with the ritual. The process of shifting the cultural significance of the phenomenon of ornament from the sacred to the decorative is considered as a mechanism for the formation of innovations on the material of the ornament of Russian embroidery and printed pattern on fabric of the 18th — early 20th centuries.

scholarly journals Suboptimal Disturbance Observer Design Using All Stabilizing Q Filter for Precise Tracking Control

Mathematics ◽  
2020 ◽  
Vol 8 (9) ◽  
pp. 1434 ◽  
Author(s):  
Wonhee Kim ◽  
Sangmin Suh
Keyword(s):  
Design Method ◽  
Industrial Applications ◽  
Point Of View ◽  
Observer Design ◽  
Linear Matrix ◽  
External Disturbances ◽  
Closed Loop Systems ◽  
Control Target ◽  
The Stability ◽  
Unified Index

For several decades, disturbance observers (DOs) have been widely utilized to enhance tracking performance by reducing external disturbances in different industrial applications. However, although a DO is a verified control structure, a conventional DO does not guarantee stability. This paper proposes a stability-guaranteed design method, while maintaining the DO structure. The proposed design method uses a linear matrix inequality (LMI)-based H∞ control because the LMI-based control guarantees the stability of closed loop systems. However, applying the DO design to the LMI framework is not trivial because there are two control targets, whereas the standard LMI stabilizes a single control target. In this study, the problem is first resolved by building a single fictitious model because the two models are serial and can be considered as a single model from the Q-filter point of view. Using the proposed design framework, all-stabilizing Q filters are calculated. In addition, for the stability and robustness of the DO, two metrics are proposed to quantify the stability and robustness and combined into a single unified index to satisfy both metrics. Based on an application example, it is verified that the proposed method is effective, with a performance improvement of 10.8%.

scholarly journals No-z Model for Magnetic Fields of Different Astrophysical Objects and Stability of the Solutions

Data ◽  
2021 ◽  
Vol 6 (1) ◽  
pp. 4
Author(s):  
Evgeny Mikhailov ◽  
Daniela Boneva ◽  
Maria Pashentseva
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Large Scale ◽  
Point Of View ◽  
Accretion Discs ◽  
Wide Range ◽  
Astrophysical Objects ◽  
Alpha Effect ◽  
The Stability ◽  
The Magnetic Field

A wide range of astrophysical objects, such as the Sun, galaxies, stars, planets, accretion discs etc., have large-scale magnetic fields. Their generation is often based on the dynamo mechanism, which is connected with joint action of the alpha-effect and differential rotation. They compete with the turbulent diffusion. If the dynamo is intensive enough, the magnetic field grows, else it decays. The magnetic field evolution is described by Steenbeck—Krause—Raedler equations, which are quite difficult to be solved. So, for different objects, specific two-dimensional models are used. As for thin discs (this shape corresponds to galaxies and accretion discs), usually, no-z approximation is used. Some of the partial derivatives are changed by the algebraic expressions, and the solenoidality condition is taken into account as well. The field generation is restricted by the equipartition value and saturates if the field becomes comparable with it. From the point of view of mathematical physics, they can be characterized as stable points of the equations. The field can come to these values monotonously or have oscillations. It depends on the type of the stability of these points, whether it is a node or focus. Here, we study the stability of such points and give examples for astrophysical applications.

scholarly journals Photoluminescent Coordination Polymers Based on Group 12 Metals and 1H-Indazole-6-Carboxylic Acid

Inorganics ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 20
Author(s):  
Antonio A. García-Valdivia ◽  
Estitxu Echenique-Errandonea ◽  
Gloria B. Ramírez-Rodríguez ◽  
José M. Delgado-López ◽  
Belén Fernández ◽  
...  
Keyword(s):  
Carboxylic Acid ◽  
Coordination Polymers ◽  
Density Functional ◽  
Free Ligand ◽  
Emission Spectra ◽  
Point Of View ◽  
Theoretical Point ◽  
Fourier Transformed Infrared Spectroscopy ◽  
3D Network ◽  
The Stability

Two new coordination polymers (CPs) based on Zn(II) and Cd(II) and 1H-indazole-6-carboxylic acid (H2L) of general formulae [Zn(L)(H2O)]n (1) and [Cd2(HL)4]n (2) have been synthesized and fully characterized by elemental analyses, Fourier transformed infrared spectroscopy and single crystal X-ray diffraction. The results indicate that compound 1 possesses double chains in its structure whereas 2 exhibits a 3D network. The intermolecular interactions, including hydrogen bonds, C–H···π and π···π stacking interactions, stabilize both crystal structures. Photoluminescence (PL) properties have shown that compounds 1 and 2 present similar emission spectra compared to the free-ligand. The emission spectra are also studied from the theoretical point of view by means of time-dependent density-functional theory (TD-DFT) calculations to confirm that ligand-centred π-π* electronic transitions govern emission of compound 1 and 2. Finally, the PL properties are also studied in aqueous solution to explore the stability and emission capacity of the compounds.

USING MALIC ACID SOLUTIONS FOR THE HYDRATION OF VEGETABLE OILS AND LECITHIN PRODUCTION

2020 ◽  
Author(s):  
Л.А. МАРЧЕНКО ◽  
Т.Н. БОКОВИКОВА ◽  
Е.В. ЛИСОВАЯ ◽  
С.А. ИЛЬИНОВА ◽  
Е.П. ВИКТОРОВА
Keyword(s):  
Malic Acid ◽  
Complex Compounds ◽  
Point Of View ◽  
Magnesium Ions ◽  
Ph Values ◽  
Calcium And Magnesium ◽  
The Stability ◽  
The Cost ◽  
Calcium And Magnesium Ions

Исследована возможность применения яблочной кислоты (ЯК) в качестве гидратирующего агента для перевода негидратируемых форм фосфолипидов в гидратируемые. Выбор ЯК обусловлен ее стоимостью, которая в 1,5 раза меньше стоимости янтарной кислоты, широко применяемой в качестве гидратирующего агента, а также большей доступностью с точки зрения промышленного производства. Исследование процесса комплексообразования и определение состава комплексных соединений ЯК с ионами кальция и магния осуществляли методом потенциометрического титрования. Установлено, что внесение в раствор ЯК ионов кальция и магния приводит к снижению значений рН, что свидетельствует о наличии комплексообразования в указанных системах. Наиболее устойчивыми являются комплексы ионов кальция и магния с непротонированным лигандом при соотношении Ме2 : лиганд 1 : 1. В процессе комплексообразования ионы Ca2 и Mg2 вытесняют протоны только карбоксильных групп ЯК, которая с ионами кальция образует более устойчивые комплексы, чем с ионами магния. Показано, что устойчивость комплексов ЯК с ионами кальция и магния значительно выше, чем устойчивость комплексов фосфатидилсеринов и фосфатидных кислот с указанными ионами. Использование водных растворов ЯК в качестве гидратирующего агента позволит повысить эффективность процесса гидратации и увеличить выход фосфолипидов и, следовательно, готового продукта лецитина. The possibility of using malic acid (MA) as a hydrating agent for converting non-hydrated forms of phospholipids into hydrated ones has been investigated. The choice of MA is due to its cost, which is 1,5 times less than the cost of succinic acid, as well as greater availability from the point of view of industrial production. The study of the complexation process and determination of the composition of complex compounds of MA with calcium and magnesium ions was carried out by the method of potentiometric titration. It was found that the introduction of calcium and magnesium ions into the MA solution leads to a decrease in pH values, which indicates the presence of complexation in these systems. Complexes of calcium and magnesium ions with an unprotected ligand at a ratio of ME2 : ligand 1 : 1 are the most stable. In the process of complexing, Ca2 and Mg2 ions displace protons only of the carboxyl groups of MA, which forms more stable complexes with calcium ions than with magnesium ions. It is shown that the stability of MA complexes with calcium and magnesium ions is significantly higher than the stability of phosphatidylserine and phosphatidic acid complexes with these ions. Using water solutions of MA as a hydrating agent will increase the efficiency of the hydration process and increase the yield of phospholipids and, consequently, the finished product lecithin.

Study on Self-Excited Vibration Mechanism of Wheel-Rail Lateral Contact System

2013 ◽  
Vol 427-429 ◽  
pp. 257-261
Author(s):  
Li Xia Sun ◽  
Jian Wei Yao ◽  
Fu Guo Hou ◽  
Xin Zhao
Keyword(s):  
Feedback Mechanism ◽  
Point Of View ◽  
Contact System ◽  
Vibration System ◽  
Lateral Contact ◽  
System A ◽  
Vibration Model ◽  
Excited Vibration ◽  
Vibration Mechanism ◽  
The Stability

In order to investigate self-excited vibration mechanism of wheel-rail lateral contact system, a two DOF elasticity position wheelset lateral vibration model is established which considers the dry friction; the mechanism of the wheelset lateral self-excited vibration is investigated from the energy point of view. It shows that: the bifurcation diagram of this wheel-rail lateral contact system has a supercritical Hopf bifurcation. The energy of self-excited vibration derives from a part of traction energy; the creep rate in the wheel-rail system act as a feedback mechanism in the wheelset lateral self-excited vibration system. The stability of the wheelset self-excited vibration system depends mainly on the total energy removed from and imported into the system.

scholarly journals Retrograde resonances in compact multi-planetary systems: a feasible stabilizing mechanism

2007 ◽  
Vol 3 (S249) ◽  
pp. 511-516 ◽  
Author(s):  
Julie Gayon ◽  
Eric Bois
Keyword(s):  
Body Problem ◽  
Extrasolar Planets ◽  
Planetary Systems ◽  
Central Star ◽  
Point Of View ◽  
Outer Planet ◽  
Mean Motion Resonances ◽  
Hot Jupiters ◽  
The Stability ◽  
Orbital Data

AbstractMulti-planet systems detected until now are in most cases characterized by hot-Jupiters close to their central star as well as high eccentricities. As a consequence, from a dynamical point of view, compact multi-planetary systems form a variety of the general N-body problem (with N ≥ 3), whose solutions are not necessarily known. Extrasolar planets are up to now found in prograde (i.e. direct) orbital motions about their host star and often in mean-motion resonances (MMR). In the present paper, we investigate a theoretical alternative suitable for the stability of compact multi-planetary systems. When the outer planet moves on a retrograde orbit in MMR with respect to the inner planet, we find that the so-called retrograde resonances present fine and characteristic structures particularly relevant for dynamical stability. We show that retrograde resonances and their resources open a family of stabilizing mechanisms involving specific behaviors of apsidal precessions. We also point up that for particular orbital data, retrograde MMRs may provide more robust stability compared to the corresponding prograde MMRs.

scholarly journals Criteria for evaluating the competencies of the school counselor at the basic education stage from the point of view of school principals in the state of Khartoum: معايير تقويم كفايات المرشد المدرسي بمرحلة تعليم الاساس من وجهة نظر مدراء المدارس بولاية الخرطوم

2017 ◽  
Vol 1 (3) ◽  
Author(s):  
Ikhlas Hassan Sayyid Echriya ◽  
Reham Anwar Mohammed Hassan
Keyword(s):  
School Counselor ◽  
Basic Education ◽  
School Principals ◽  
Pearson Correlation ◽  
Statistical Significance ◽  
Correlation Equation ◽  
Significance Test ◽  
Point Of View ◽  
The Stability ◽  
Extension Process

The aim of this study was to investigate the criteria of evaluating the competencies of the school counselor in the basic education stage, from the point of view of the school principals in Khartoum State, to achieve the objectives of the study. The researchers prepared a questionnaire that was applied during the academic year 2014-2015 to a random sample of 20 managers in basic education Khartoum, a maritime locality, the questionnaire contains six criteria for evaluating the school's competencies: planning the extension process, implementing the extension process, designing the extension programs, effective communication skills, using the technique in the extension process, In order to ascertain the stability and validity of the questionnaire, by means of the Alpha Kronbach equation and to verify the persistence of the questionnaire by Pearson correlation equation for the questionnaire items in the overall degree of the questionnaire, the sincerity of the arbitrators was measured by presenting it to a number of curriculum experts and pedagogic and educational psychologists in different Sudanese universities. Statistical packages of social sciences (SPSS), and statistical methods used to analyze repetitive data: percentages, arithmetical averages, standard deviations, mono variance, applied statistical significance test (T) The results of the study were reached by a number of recommendations, the most important of which are the need to develop an integrated methodology and a clear job description. For the role of the educational guide, and the process of educational guidance of schools based on the academic procedures of higher education, the need to contribute sections of educational psychology in the quality models and procedures to control and follow up the implementation of strategic plans for the tasks of the school guide and evaluate, The number of educational counselors for the number of learners and the creation of the guiding environment.

scholarly journals Qualifications for teachers and teachers of gifted students in Jeddah

2018 ◽  
Vol 2 (4) ◽  
Author(s):  
Ibtisam Rashad Abdullah Hameedah
Keyword(s):  
Random Sample ◽  
Gifted Students ◽  
Point Of View ◽  
Average Score ◽  
Stability Factor ◽  
Years Of Experience ◽  
Jeddah City ◽  
Study Population ◽  
Descriptive Approach ◽  
The Stability

This study aimed to identify the qualitative competencies of teachers and teachers of gifted students in Jeddah from their point of view and to indicate the extent of these competencies according to the variables of the study: gender, scientific qualification and years of experience. We have used the descriptive approach, as a questionnaire was developed to collect data, verified its validity and stability in the appropriate educational and statistical methods, and the value of the stability factor, Kronbach Alpha, (0.75). The study population is composed of all teachers and teachers of the gifted students in the schools of Jeddah city (70) teachers and teachers, a random sample was selected (40%). The results of the study showed that the qualitative competencies of teachers and teachers of gifted students came in a medium and an average score of (3.31) according to the Likert quintile scale. The results also showed that there were statistically significant differences between the estimations of the sample of the study of the qualitative competencies of teachers and gifted students in Jeddah For the sex variable, and the absence of differences attributed to the variable of scientific qualification, and years of experience.

EVOLUTION AND CULTURAL SIGNIFICANCE OF GREEN PUBLIC SPACES IN KRASNOYARSK

2021 ◽  
pp. 29-42
Author(s):  
Olga N. Bliankinshyein ◽  
◽  
Natalya A. Popkova ◽  
Keyword(s):  
Urban Environment ◽  
Public Spaces ◽  
Point Of View ◽  
Green Spaces ◽  
Great Effort ◽  
Cultural Significance ◽  
Photographic Recording ◽  
Green Areas ◽  
The City ◽  
Cultural Role

One of the criteria for a comfortable ecologically clean urban environment is access to green spaces, their number and quality in any given city. Public green spaces play an important socio-cultural role in the context of active and passive recreation of citizens, various types of recreational activities. The relevance of this study is due to increased attention to the formation of open public spaces in the city of Krasnoyarsk. The purpose of this work is to trace the evolution and identify the social and cultural significance of the green public spaces in Krasnoyarsk. The objectives of the research are to study the green spaces of Krasnoyarsk in a historical retrospective, analyze the green spaces of Krasnoyarsk from the point of view of their ecological significance, recreational use. Research methods included literature review on the topic, analysis of historical data, field survey of the territory, long-term observation, photographic recording, comparative retrospective analysis, and graphic-analytical method. The study captures the most common types of public green spaces and their role in creating a comfortable urban environment. It traces in the most detail the evolution and cultural significance of the most important historical green spaces in Krasnoyarsk: the City Garden (now the Central Park), Yudinsky Garden, Krutovsky Garden. These examples show that gardens and parks can be formed both on the basis of the natural environment of urban forests, and artificially created by the efforts of citizens, that over time they can undergo various quantitative and qualitative, planning and functional transformations. Despite the transformations that have taken place, all the studied historical objects still exist and are used for their intended purpose. In addition to these historical green areas, we examine the newly organized public green spaces with a cultural and recreational component over the past decades: Tatyshev Park, All-season Fun-Park Bobrovy Log, Flora and Fauna Park Roev Ruchey, Dream Gardens and others. The article notes the importance of municipal, public and private initiatives in the organization of local green areas. The analysis allows us to assert that there is a certain system of public green spaces in Krasnoyarsk. It has disadvantages, such as an uneven distribution of green areas throughout the city, lack of interconnections between individual elements, aging of certain areas of greenery, and the complete destruction of some. Nevertheless, the city authorities, architects, designers and the general public make great effort to create a green framework for Krasnoyarsk destined to have an important recreational and cultural role.

Stability of a Piezoresistive Ceramic Pressure Sensor Made With LTCC Technology

2012 ◽  
Vol 2012 (CICMT) ◽  
pp. 000371-000376 ◽  
Author(s):  
Marina Santo Zarnik ◽  
Darko Belavic
Keyword(s):  
Pressure Sensor ◽  
Fatigue Testing ◽  
Low Pressure ◽  
Fatigue Tests ◽  
Point Of View ◽  
Long Term Stability ◽  
Pressure Cycling ◽  
Key Characteristics ◽  
The Stability

This paper discusses the stability of a piezoresistive, LTCC-based, pressure sensor that was designed for measurements in a low-pressure range below 100 mbar. The intrinsic stability of the sensor's offset was evaluated at a constant ambient temperature and different conditions regarding the atmospheric humidity. The sensors were also subjected to functional fatigue tests, which included a full-scale and an overload pressure cycling. The results of the fatigue testing revealed the vulnerability of the sensor's structure from the point of view of the long-term stability and the life-cycle. Nevertheless, the stability of the key characteristics of the prototype sensors was found to be satisfactory for accurate measurements in the low-pressure ranges.

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