scholarly journals Analysis methodology for the design of start-up rheostats on thermo-dependent polycrystalline resistances

2021 ◽  
Vol 2131 (4) ◽  
pp. 042070
Author(s):  
N P Voronova
Keyword(s):  
Low Cost ◽  
Autonomous Systems ◽  
Electrical Control ◽  
Analysis Methodology ◽  
Start Up ◽  
Electrical Devices ◽  
Limited Power ◽  
Starting Process ◽  
Polycrystalline Semiconductor ◽  
Thermistor Material

Abstract The article provides a brief analysis of the starting processes of electrical devices in autonomous systems of limited power. The existing methods of automatic start-up and regulation of the operation of electrical machines and apparatus are considered, which are a multi-link system, the reliability of which is determined by a number of intermediate links, and the stepping is one of the biggest drawbacks that negatively affect the dynamics of the starting process. In addition, the issues of simplicity, low cost and small dimensions of the automatic control system for electrical installations are of particular importance in the problem of energy saving. The use of low-power thermistors as part of starting devices requires intermediate equipment and various components, which significantly reduces the reliability of the equipment. The increase in currents flowing through the ballasts simplifies the electrical control and regulation circuits. For the use of polycrystalline semiconductor thermistors in circuits with high currents, it is necessary to use special designs in order to prevent overheating of the thermistor material. The article provides algorithms for the synthesis of starting rheostats. A number of restrictions are considered and formulated, on which the nature of the processes of starting electric motors with the help of thermistor rheostats, which ensure the fulfillment of certain restrictions, depends. Recommendations are given for the formation of optimal starting processes using rheostats built on semiconductor polycrystalline thermistors.

scholarly journals Effectiveness of National Airlines in Europe – the DEA Approach

2016 ◽  
Vol 16 (2) ◽  
pp. 103-118 ◽  
Author(s):  
Agata Żółtaszek ◽  
Renata Pisarek
Keyword(s):  
Low Cost ◽  
Air Transport ◽  
Competitive Environment ◽  
Load Factor ◽  
Data Envelopment ◽  
Eu Member States ◽  
Analysis Methodology ◽  
Low Cost Carriers ◽  
Dea Approach ◽  
Regional Airports

Abstract National airlines operate in a highly competitive environment. EU airlines face a challenge to compete with low cost carriers, as a result of the liberalization process in the sector. European flag airlines of non-EU member states, not benefiting from liberalization, are forced to compete internationally. This research is focused on national carriers, as they provide the majority of service to and from central and regional airports. Therefore, to establish the most efficient entities on the passenger air transport market, DEA (Data Envelopment Analysis) methodology, has been utilized. The purpose of this paper is to evaluate the effectiveness of 29 chosen national airlines in Europe in the year 2013, using the DEA approach, to pinpoint the subset of fully-efficient market leaders, as well as potential sources of inefficiency, among less effective carriers. The analysis incorporates information on inputs (e.g. fleet, number of employees, number of countries and airports served) and outputs (revenue, annual passengers carried, load factor). The results show that more than 40% (12 of 29) researched airlines are effective and the other 34% are near-efficient. Moreover, outcomes suggest that “going big” may not increase effectiveness. It is harder to achieve full efficiency for big carriers than small ones.

scholarly journals APPLICATION OF PLASMA-ELECTROLYTE COATINGS ON TITANIUM WITH REFRACTORY METALS FOR DETOXIFICATION OF ENVIRONMENTS FROM POLLUTING SUBSTANCES

2021 ◽  
pp. 96-102
Author(s):  
Mykola Sakhnenko ◽  
Serhii Indykov ◽  
Hanna Karakurkchi
Keyword(s):  
Photocatalytic Activity ◽  
Low Cost ◽  
Autonomous Systems ◽  
Quantitative Composition ◽  
High Catalytic Activity ◽  
Catalytic Layer ◽  
Oxide Systems ◽  
Metal Compounds ◽  
Anthropogenic Pollutants ◽  
Plasma Electrolyte

Based on the review of the peculiarities of the photocatalytic processes, the peculiarities of the catalytic action of oxide systems based on titanium dioxide are determined. It is shown that TiO2 is one of the most chemically and thermally stable and non-toxic inorganic oxides of semiconductors, whose photocatalytic activity is manifested by irradiation with ultraviolet part of the spectrum (λ 320–400 nm) and allows the oxidation of a significant amount of toxic agents to water and carbon dioxide. The essence of the photocatalytic process of oxidation of toxicants under the action of UV radiation on the TiO2 surface is considered. The proposed technology of photocatalytic detoxification of contaminants is economically available, environmentally friendly and allows its widespread use, in particular for autonomous systems, including dual purpose. It is established that the main requirements for materials for photocatalysis are their chemical and biological inertness, photocatalytic stability and activity, low cost. It is shown that the most rational technological form of the photocatalyst is the application (synthesis) of the catalytic layer on structured metal substrates, in particular titanium alloys. It is proved that these catalytic oxide systems can be effectively formed by the method of plasma-electrolyte oxidation in aqueous electrolytes with the addition of dopant metal compounds that increase the photocatalytic activity of the obtained heterooxide systems. It is proposed to use tungsten oxides of variable valence as the target additive. The kinetic regularities of the process of plasma-electrolytic oxidation of titanium VT1-0 in a diphosphate-borate electrolyte with the addition of tungstates have been studied. It is shown that in an electrolyte of this type at a current density of 1.0 A/dm2 in the galvanostatic mode for 30 min a uniform coating of TiO2·WxOy with a tubular torus-like structure and tungsten content of 2.5–7.5 wt.% is formed. The predicted quantitative composition of the heteroxide layer in combination with the surface morphology creates the preconditions for high catalytic activity of the synthesized coating for detoxification of media from anthropogenic pollutants.

Development of a low-cost smart vehicle start up and tracking system using Android and Arduino

2020 ◽  
Vol 15 (3/4) ◽  
pp. 271
Author(s):  
Sundresan Perumal ◽  
Mujahid Tabassum ◽  
Dayang Siti Nur Amirah Bt Ab Ahmad Zulkipli
Keyword(s):  
Tracking System ◽  
Low Cost ◽  
Start Up ◽  
Smart Vehicle

Advanced SiP Packaging Technologies of IPD for Mobile Applications

2010 ◽  
Vol 2010 (DPC) ◽  
pp. 1-20
Author(s):  
Geun Sik Kim ◽  
Kai Liu ◽  
Flynn Carson ◽  
Seung Wook Yoon ◽  
Meenakshi Padmanathan
Keyword(s):  
High Performance ◽  
Low Cost ◽  
Autonomous Systems ◽  
System Level ◽  
Design And Technology ◽  
Wafer Level ◽  
Future Technology ◽  
Rf Transceivers ◽  
And Performance ◽  
3D Stacking

IPD technology was originally developed as a way to replace bulky discrete passive components, but it¡¯s now gaining popularity in ESD/EMI protection applications, as well as in RF, high-brightness LED silicon sub-mounts, and digital and mixed-signal devices. Already well known as a key enabler of system-in-packages (SiPs), IPDs enable the assembly of increasingly complete and autonomous systems with the integration of diverse electronic functions such as sensors, RF transceivers, MEMS, power amplifiers, power management units, and digital processors. The application area for IPD will continue to evolve, especially as new packaging technology, such as flipchip, 3D stacking, wafer level packaging become available to provide vertical interconnections within the IPD. New applications like silicon interposers will become increasingly significant to the market. Currently the IPD market is being driven primarily by RF or wireless packages and applications including, but not limited to, cell phones, WiFi, GPS, WiMAX, and WiBro. In particular, applications and products in the emerging RF CMOS market that require a low cost, smaller size, and high performance are driving demand. In order to get right products in size and performance, packaging design and technology should be considered in device integration and implemented together in IPD designs. In addition, a comprehensive understanding of electrical and mechanical properties in component and system level design is important. This paper will highlight some of the recent advancements in SiP technology for IPD and integration as well as what is developed to address future technology requirements in IPD SiP solutions. The advantage and applications of SiP solution for IPD will be presented with several examples of IPD products. The design, assembly and packaging challenges and performance characteristics will be also discussed.

Time Slicing Method

2011 ◽  
pp. 272-279
Author(s):  
Phillip K.C. Tse
Keyword(s):  
High Throughput ◽  
Storage Capacity ◽  
Low Cost ◽  
Storage Devices ◽  
Access Latency ◽  
Tertiary Storage ◽  
Start Up ◽  
Slicing Method ◽  
Time Slicing

Tertiary storage devices provide huge storage capacity at low cost. Multimedia objects stored on the tertiary storage devices are accessed with high latency. Despite the high access latency, some tertiary storage devices are able to deliver data at high throughput. The time slicing method is designed to reduce the start-up latency in accessing multimedia objects from tertiary storage devices. The start-up latency is lowered by reducing the amount of data being migrated in stage one of the staging method being described in the last chapter. In order to support the time-slicing method, the tertiary storage devices should have the ability to deliver data at high throughput. The tertiary storage devices that cannot deliver data at sufficiently high throughput; the start-up latency cannot be reduced.

START-UP STRATEGY FOR SBR TREATMENT OF COMPLEX INDUSTRIAL WASTEWATER

1994 ◽  
Vol 30 (3) ◽  
pp. 149-155
Author(s):  
M. Muñiz ◽  
A. G. Lavin ◽  
M. Díaz
Keyword(s):  
Industrial Wastewater ◽  
Low Cost ◽  
Process Efficiency ◽  
Normal Operation ◽  
Organic Load ◽  
Feeding Time ◽  
Good Test ◽  
High Salinity Water ◽  
Start Up ◽  
Complex Organic

In SBR processes, the start-up operation is of considerable interest, not only because of the effect of the efficiency on normal operation, but also because of the cost of the transport of sludge seed and the related feeding time with artificial substrate. The selection of the strategy bas not been studied previously as far as we know, although it is a problem of considerable economic importance. This is not only a problem of the relation between seed magnitude and the start-up timing, but also the effect on the process efficiency. The start-up in SBRs is more frequent than in conventional activated sludge when considering SBRs are mainly used for industrial wastewater treatment, where there are more stops and changes of organic load. A start-up strategy for SBR biological treatment of industrial wastewater with several complex organic components, based on two steps (Filling and Conditioning Periods), bas been proposed and put into operation in a pilot plant column. The strategy looks for minimum time to achieve high steady state efficiency, and low cost of implementation, and sludge seeding. It makes a provision for feed on the basis of inhibition potential and organic needs, and introduces instructions during the operation, depending on the results being obtained. The results of this strategy using a complex organic high salinity water are presented. The presence in this case of two types of solvents and very high salts concentration has been a good test problem for the proposed strategy because of the necessity of multiple adaptation of sludge and the considerably difficult problem to be solved.

Application of Bond-Graph Method in Microjet Engine Cold Start Modeling to Investigate the Idea of Injecting Compressed Air

2015 ◽  
Vol 799-800 ◽  
pp. 890-894 ◽  
Author(s):  
Morteza Montazeri-Gh ◽  
Seyed Alireza Miran-F
Keyword(s):  
Bond Graph ◽  
Compressed Air ◽  
Labview Software ◽  
Cold Starting ◽  
Graph Modeling ◽  
Start Up ◽  
Proposed Model ◽  
Bond Graph Modeling ◽  
Starting Process ◽  
Good Agreement

This paper presents the application of bond-graph modeling for investigation of the microjet engine in cold starting mode. In this model, the idea of simultaneous usage of the compressed air and electric starter is developed to perform the starting process. For this purpose, the microjet engine is assembled by components which is provided by the engine manufacturer, then a monitoring system in Labview software is developed. Dynamic modeling of the engine cold starting phase is performed by bond graph approach and simulated in 20-sim software. So, the allowable air pressure to inject during the starting process is calculated. The simulation results are then compared with experimental data where a good agreement is observed. These results support the proposed model for further analysis to improve the performance of engine start-up process.

The Modeling and Simulation of Super-Capacitor in Diesel Engine Starting Process

2012 ◽  
Vol 229-231 ◽  
pp. 1967-1970
Author(s):  
Zhen Min Cui ◽  
Ru Wang
Keyword(s):  
Diesel Engine ◽  
System Modeling ◽  
Super Capacitor ◽  
Power Characteristics ◽  
Modeling Simulation ◽  
Auxiliary Power ◽  
Start Up ◽  
Instantaneous Discharge ◽  
Starting Process ◽  
Engine Start

Diesel engine; Super-capacitor; Starter system; Modeling; Simulation Abstract. In order to improve the start-up performance of the diesel engine and the working conditions of batteries, make efficient use of the high instantaneous discharge power characteristics of the super-capacitor as a diesel engine start-up auxiliary power. Taking the YC6J180 types of Yuchai diesel engine as illustration, diesel engine starting process was modeled and simulated by Matlab/Simulink software, and compared with the simulation model of diesel engine starting system added the super-capacitor. The simulation results show that the diesel engine starter system added the super-capacitor as the auxiliary power, the starting performance is improved significantly, meanwhile improve the battery state, and extend its service life.

scholarly journals Strength and dynamic characteristics analyses of wound composite axial impeller

2012 ◽  
Vol 2 (1) ◽  
Author(s):  
Jifeng Wang ◽  
Jorge Olortegui-Yume ◽  
Norbert Müller
Keyword(s):  
Dynamic Characteristics ◽  
High Performance ◽  
Low Cost ◽  
Three Dimensional ◽  
Design Parameters ◽  
Modal Shape ◽  
Kevlar Fiber ◽  
Start Up ◽  
High Performance Composite ◽  
Wound Composite

AbstractA low cost, light weight, high performance composite material turbomachinery impeller with a uniquely designed blade patterns is analyzed. Such impellers can economically enable refrigeration plants to use water as a refrigerant (R718). A strength and dynamic characteristics analyses procedure is developed to assess the maximum stresses and natural frequencies of these wound composite axial impellers under operating loading conditions. Numerical simulation using FEM for two-dimensional and three-dimensional impellers was investigated. A commercially available software ANSYS is used for the finite element calculations. Analysis is done for different blade geometries and then suggestions are made for optimum design parameters. In order to avoid operating at resonance, which can make impellers suffer a significant reduction in the design life, the designer must calculate the natural frequency and modal shape of the impeller to analyze the dynamic characteristics. The results show that using composite Kevlar fiber/epoxy matrix enables the impeller to run at high tip speed and withstand the stresses, no critical speed will be matched during start-up and shut-down, and that mass imbalances of the impeller shall not pose a critical problem.

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