scholarly journals ПРОФІЛОМЕТРІЮВАННЯ КРОМОК РОЗРЯДНОЇ КАМЕРИ СТАЦІОНАРНОГО ПЛАЗМОВОГО ДВИГУНА

2018 ◽  
pp. 91-96
Author(s):  
Алена Николаевна Хаустова ◽  
Андрей Виталиевич Лоян ◽  
Олег Петрович Рыбалов ◽  
Евгений Иванович Ищенко
Keyword(s):  
Discharge Chamber ◽  
Operation Time ◽  
Time Trial ◽  
High Energy ◽  
Contact Method ◽  
Factors Affecting ◽  
Advantages And Disadvantages ◽  
Erosion Processes ◽  
Long Time ◽  
Stationary Plasma Thrusters

The effectiveness of stationary plasma thrusters was proved by many years of experience of their on board operation on various spacecraft especially on geostationary orbits. One of the main factors that affects the duration of the SPT operation time is the lifetime of the edges of the discharge chamber walls. One of the factors affecting the discharge chamber lifetime is the erosion of the edges of the insulators. Ceramic wear is cause by the destruction of the high-energy ion flow that takes place in thruster plasma.Theoretical study of the processes of discharge chamber insulators sputtering still does not allow mathematically determining the rate of development of the ceramic edges erosion processes with the necessary accuracy that is required for the SPT lifetime forecast. That is why all the researches require a full-scale testing of the thruster on a long time trial basis with subsequent measurements of the insulators value of erosion.In this paper, several methods for measuring the degree of insulators wear are considered. The analysis of the method for measuring the thickness of the ends of discharge chamber insulators was carried out, followed by the determination of radial erosion. It has been shown that this method is the most suitable for non-separable constructions of SPT due to the high accuracy of the measurements and its simplicity.A method for noncontact profilometry of the edges of thruster discharge chamber insulators was proposed. The use of a non-contact method allows measurements to be carried out, excluding the possibility of any deformations to the surface of insulators. Measurements were provided with the help of modern metallographic microscope. Advantages and disadvantages of the methodology are shown. The analysis of the factors that influences the error during measurements of the ceramic profile is carried out.A method is proposed for contact profilometry of the edges of thruster discharge chamber insulators. Advantages and disadvantages of the methodology are shown. The results of measurements of the profile of the two thrusters with the construction differences are provided.

ANALYSIS OF DOMESTIC AND FOREIGN TECHNICAL MEANS FOR THE CULTIVATION OF POTATOES AND JERUSALEM ARTICHOKE ON SEED PLOT

2020 ◽  
Vol 4 (41) ◽  
pp. 144-150
Author(s):  
STEPAN SEMICHEV ◽  
Keyword(s):  
Rational Design ◽  
Jerusalem Artichoke ◽  
High Energy ◽  
Research Purpose ◽  
Seed Plot ◽  
Factors Affecting ◽  
Advantages And Disadvantages ◽  
Rotation Axes ◽  
One Machine

Growing potatoes involves extensive ground preparation. Factors affecting the crop are air and moisture permeability of the soil. (Research purpose) The research purpose is in analyzing existing domestic and foreign technical means for growing potatoes and Jerusalem artichoke on seed plot. (Materials and methods) The article presents the advantages and disadvantages of using vertical and horizontal tillage cutters. Authors have analyzed existing domestic and foreign tillage cutters and tools and their applications. (Results and discussion) For high-quality pre-planting tillage there are widely used cutters with horizontal and vertical rotation axes; for loosening the lower layers of soil under a seed plot there are used various paws installed on the cutters; in order to perform several operations by one machine, in particular, continuous milling with loosening the lower layers and strip milling with cutting ridges, separate designs of horizontal cutters contain replaceable both a roller and an apron-ridgeformer. Due to the use of replaceable tools, horizontal cutters are more suitable for performing different operations than vertical ones; a rational design of a milling cultivator for pre-planting soil treatment should contains replaceable organs for continuous milling and leveling the top layer of soil and forming ridges before planting and when caring for potato and Jerusalem artichoke plantings. (Conclusions) Pre-planting milling of the soil for potatoes is better than traditional. Despite the high energy intensity of the process of preparing the soil for planting potatoes, the quality of milling cultivators exceeds the agrotechnical performance of non-driving machines.

A Stationary Solution of High-Energy Electron Reflection (HEER) for An Arbitrary Surface

1990 ◽  
Vol 48 (2) ◽  
pp. 374-375
Author(s):  
YIQUN MA
Keyword(s):  
Stationary Solution ◽  
High Energy ◽  
Bloch Wave ◽  
Dynamical Theory ◽  
High Energy Electron ◽  
Bulk Materials ◽  
Periodic Surface ◽  
Electron Transmission ◽  
Electron Reflection ◽  
Long Time

For a long time, the development of dynamical theory for HEER has been stagnated for several reasons. Although the Bloch wave method is powerful for the understanding of physical insights of electron diffraction, particularly electron transmission diffraction, it is not readily available for the simulation of various surface imperfection in electron reflection diffraction since it is basically a method for bulk materials and perfect surface. When the multislice method due to Cowley & Moodie is used for electron reflection, the “edge effects” stand firmly in the way of reaching a stationary solution for HEER. The multislice method due to Maksym & Beeby is valid only for an 2-D periodic surface.Now, a method for solving stationary solution of HEER for an arbitrary surface is available, which is called the Edge Patching method in Multislice-Only mode (the EPMO method). The analytical basis for this method can be attributed to two important characters of HEER: 1) 2-D dependence of the wave fields and 2) the Picard iteractionlike character of multislice calculation due to Cowley and Moodie in the Bragg case.

An overview of Osmotic Drug Delivery System: An update review

2017 ◽  
Vol 6 (7) ◽  
pp. 5426 ◽  
Author(s):  
Hiren J. Patel ◽  
Vaishnavi P. Parikh
Keyword(s):  
Drug Delivery ◽  
Drug Delivery Systems ◽  
Life Cycle Management ◽  
Delivery Systems ◽  
Osmotic Pump ◽  
Factors Affecting ◽  
Advantages And Disadvantages ◽  
New Chemical Entities ◽  
History Of ◽  
Novel Drug

The pharmaceutical industry has faced several marked challenges in order to bring new chemical entities (NCEs) into the market over the past few decades. Various novel drug delivery approaches have been used as a part of life cycle management from which Osmotic drug delivery systems look the most promising one. After discussing the history of osmotic pump development, this article looks at the principles, advantages and disadvantages of osmotic drug delivery systems. Then, the basic components of osmotic pump and factors affecting the design of oral osmotic drug delivery systems are discussed in detail. In the later part of the manuscript, various types of osmotic pumps available in the market and evaluation methods for osmotic drug delivery systems are discussed in detail.

Using Self-report to Study How Application affect Motivation of Behavior Change (Preprint)

2020 ◽  
Author(s):  
Yuan Yin ◽  
Yurong Yu
Keyword(s):  
Behavior Change ◽  
Self Report ◽  
Group Method ◽  
Behavior Changes ◽  
Technology Design ◽  
Factors Affecting ◽  
Negative Results ◽  
Long Time ◽  
Ecological Momentary ◽  
Positive Effect

BACKGROUND Currently, changing behaviors with the assistance of mobile applications has been popularized. However, most of the participants are unable to persist in participating in behavior-changing activities for a long time. Some researchers have studied what factors motivate people to maintain behaviors-changing actions. There has been controversy about whether the commonly used triggers, negative results or competitions, could motivate behavior changes. In the meantime, the main methodology these researchers have been using is to conduct experiments, from which data was collected from subjects’ recalling previous behavior changing. The experiments are time-consuming, and the results can be unreliable. To resolve this problem, the Ecological Momentary Assessment (EMA) was developed to record real-time feedback. However, the EMA unavoidably increases the workload of the subjects. OBJECTIVE This study investigated the factors affecting behavior change, especially from the motivation aspect. Additionally, this paper attempted to identify a way to record human behavior changes without increasing the subjects’ workload. METHODS The methodology of “self-report” was adopted to report how people’s views regarding the behavior-changing intervention. To achieve a balance between workload and being timely, the self-reporting data was recorded once a day. After the 28-day “self-report” experiment, the “focus group” method was used to gather people’s feedback on behavior changing process. RESULTS This paper identified 9 factors: cooperation, competition, award, understandable graphic, reminder and alarm, trust and willing, gender, relation with disease and environmental factors). These factors could affect motivation of behavior changing. Besides, we found that negative results could be a motivation for behavior changing. In the experiment, we also found that a small number of subjects tended to cheat for a more “beautiful” result. The last part of the paper has presented possible implications for technology design to facilitate behavior-changing. CONCLUSIONS In particular, (i) the research promoted the possibility of cheating when recording data which is ignored by existing research and will make the digital applications less useful; (ii) the results show that not all cooperation is needed to lead to a positive effect; (iii) the research identified the negative results caused by over-competition in behavior change. Finally, the paper proposes technology design directions should focus on giving motivation through keeping dairy, negative results feedback and avoid cheating.

scholarly journals Core Elements Affecting Sharing: Evidence from the United States

2021 ◽  
Vol 13 (7) ◽  
pp. 3943
Author(s):  
Aurelija Burinskienė ◽  
Edita Leonavičienė ◽  
Virginija Grybaitė ◽  
Olga Lingaitienė ◽  
Juozas Merkevičius
Keyword(s):  
United States ◽  
The United States ◽  
Collaborative Consumption ◽  
Factors Affecting ◽  
Use Of Resources ◽  
Personal Consumption ◽  
Depth Analysis ◽  
Core Elements ◽  
Long Time ◽  
Number Of Visits

The new phenomenon called sharing or collaborative consumption emerged a decade ago and is continuously growing. It creates new possibilities for society, and especially for business, is beneficial for the environment, makes more efficient use of resources, and presents a new competitive business model. The scientific literature lacks a more in-depth analysis of the factors influencing sharing activity growth; therefore, the paper’s authors attempt to fill this gap. The authors aim to identify the factors affecting the use of sharing platforms. To reach the goal, the authors developed a regression model and constructed a list of 71 variables. The study used monthly United States data from January 2017 to June 2020 from the publicly available Federal Reserve Economic Data (FRED)and Google trends databases. The comparison to other indexes proves that the proposed index, representing the number of visits to sharing platforms (SEP), is a unique one. The first index allowed us to revise the sharing activity monthly. The authors identified that variables such as wage level, social network users, import level, and personal consumption are critical in affecting the number of visits to sharing platforms. The presented framework could be helpful for practitioners and policymakers analysing the stimulation of sharing or collaborative consumption. It includes indicators representing different areas, such as society, technology, and country, and allows for monthly investigations. Such activity was evident for a long time when online platforms contributed to its wider accessibility. The results help to forecast the number of visits monthly. Sharing is still an emerging area for research; thus, the authors tried to explore the phenomenon of sharing to expand the conceptual level of knowledge.

scholarly journals Mathematical modeling and experimental study on solid–liquid suspension separation in ultrasonic standing wave field

2021 ◽  
pp. 146134842110229
Author(s):  
Yajing Wang ◽  
Liqun Wu ◽  
Yaxing Wang ◽  
Yafei Fan
Keyword(s):  
Standing Wave ◽  
Sound Pressure ◽  
Acoustic Radiation ◽  
Sound Field ◽  
Radiation Force ◽  
High Energy ◽  
Factors Affecting ◽  
Liquid Suspension ◽  
Ultrasonic Standing Wave ◽  
Solid Liquid

A new method of removing waste chips is proposed by focusing on the key factors affecting the processing quality and efficiency of high energy beams. Firstly, a mathematical model has been established to provide the theoretical basis for the separation of solid–liquid suspension under ultrasonic standing wave. Secondly, the distribution of sound field with and without droplet has been simulated. Thirdly, the deformation and movement of droplets are simulated and tested. It is found that the sound pressure around the droplet is greater than the sound pressure in the droplet, which can promote the separation of droplets and provide theoretical support for the ultrasonic suspension separation of droplet; under the interaction of acoustic radiation force, surface tension, adhesion, and static pressure, the droplet is deformed so that the gas fluid around the droplet is concentrated in the center to achieve droplet separation, and the droplet just as a flat ball with a central sag is stably suspended in the acoustic wave node.

scholarly journals Electromagnetic power of lightning superbolts from Earth to space

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
J.-F. Ripoll ◽  
T. Farges ◽  
D. M. Malaspina ◽  
G. S. Cunningham ◽  
E. H. Lay ◽  
...  
Keyword(s):  
Low Frequency ◽  
Optical Emission ◽  
High Energy ◽  
Very Low Frequency ◽  
Electromagnetic Power ◽  
Power Spectral ◽  
High Energy Tail ◽  
Van Allen Probes ◽  
Long Time ◽  
Low Frequency Waves

AbstractLightning superbolts are the most powerful and rare lightning events with intense optical emission, first identified from space. Superbolt events occurred in 2010-2018 could be localized by extracting the high energy tail of the lightning stroke signals measured by the very low frequency ground stations of the World-Wide Lightning Location Network. Here, we report electromagnetic observations of superbolts from space using Van Allen Probes satellite measurements, and ground measurements, and with two events measured both from ground and space. From burst-triggered measurements, we compute electric and magnetic power spectral density for very low frequency waves driven by superbolts, both on Earth and transmitted into space, demonstrating that superbolts transmit 10-1000 times more powerful very low frequency waves into space than typical strokes and revealing that their extreme nature is observed in space. We find several properties of superbolts that notably differ from most lightning flashes; a more symmetric first ground-wave peak due to a longer rise time, larger peak current, weaker decay of electromagnetic power density in space with distance, and a power mostly confined in the very low frequency range. Their signal is absent in space during day times and is received with a long-time delay on the Van Allen Probes. These results have implications for our understanding of lightning and superbolts, for ionosphere-magnetosphere wave transmission, wave propagation in space, and remote sensing of extreme events.

Prospects for fast reactors

1987 ◽  
Vol 92 (1-2) ◽  
pp. 57-71
Author(s):  
C. W. Blumfield
Keyword(s):  
Fast Reactor ◽  
High Energy ◽  
High Energy Density ◽  
Fast Reactors ◽  
Advantages And Disadvantages ◽  
Reactor Technology ◽  
European Collaboration ◽  
Fast Reactor Fuel ◽  
Fuel Reprocessing ◽  
Planned Activities

SynopsisThe background to recent major advances in the construction and operation of fast reactors is outlined with particular reference to the Dounreay Prototype Fast Reactor. The advantages and disadvantages of sodium as a coolant of the high energy density assembly are discussed and an account given of the consequences of a leak and the precautions taken against this eventuality. Attention is drawn to the safety aspects of the system. The economics of the plans for fuel reprocessing are explained and an account given of the progress in the fabrication of fast reactor fuel pins. Finally the environmental impact of present and planned activities on the Dounreay site is presented in the context of participation in the European Collaboration on Fast Reactor Technology and attention drawn to the importance of the planning inquiry in progress at Dounreay.

Silver Metal Pattern Fabrication on a Glass Substrate Using a Conformal Contact Printing

2013 ◽  
Vol 646 ◽  
pp. 106-110
Author(s):  
Da Hyeok Lee ◽  
Se Geun Park ◽  
Myoung Soo Kim ◽  
Young Hwan Cha ◽  
Beom Hoan O ◽  
...  
Keyword(s):  
Glass Substrate ◽  
Metal Films ◽  
Contact Method ◽  
Mold Surface ◽  
Contact Printing ◽  
Factors Affecting ◽  
Glass Substrates ◽  
Metal Pattern ◽  
Transfer Method ◽  
Conformal Contact

This paper describes a simple metal pattern transfer method on glass substrates. Ag metal films were transferred by the conformal contact method at 150°C, which did not require higher pressure than the conventional nano-imprinting method. The important factors affecting quality of transferred metal patterns on glass were the usage of anti-sticking layer on mold surface, thickness of transferred metal films and temperature during contact printing step. Various Ag patterns were transferred onto glass substrate.

scholarly journals Radiocarbon Dating of Holocene Calcareous Tufa in Southern Poland

Radiocarbon ◽  
1988 ◽  
Vol 30 (2) ◽  
pp. 133-152 ◽  
Author(s):  
Anna Pazdur ◽  
Mieczysław F Pazdur ◽  
Joachim Szulc
Keyword(s):  
High Energy ◽  
Clear Correlation ◽  
Carbonate Sediments ◽  
Radiocarbon Dates ◽  
Factors Affecting ◽  
Southern Poland ◽  
Calcareous Tufa ◽  
Organic Fractions ◽  
Apparent Age

Calcareous tufa from five sites in southern Poland, representing several most typical conditions of tufa sedimentation, were chosen for 14C, 13C, and 18O measurements. These tufas were deposited in a high-energy turbulent stream (the Racławka site), in streams with moderate but variable flow (Rzerzuśnia and Trzebienice), and in semilimnic conditions (Sieradowice site). Sediments of the Gliczarów site represent spring travertines. In all but the latter site, direct comparison of 14C dates of carbonate and organic fractions was possible, leading to an estimate of initial apparent age of carbonate sediments. Clear correlation was found between the value of initial apparent age of tufas and the hydrodynamic conditions of sedimentation. Corresponding values range from ca 3900 yr (Racławka) to 910 yr for semilimnic sediments (Sieradowice). Intermediate, almost identical values, equal to 2460 ± 200 yr and 2100 ± 160 yr, were obtained for tufas from Rzerzuśnia and Trzebienice, respectively. Detailed sedimentologic classification of tufaceous deposits is presented and some primary and secondary factors affecting the accuracy of radiocarbon dates of various types of tufas are also discussed.

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