scholarly journals INVESTIGATION OF THE TEMPERATURE FACTORS INFLUENCE ON OPERATING SAFETY THE SUBMERSIBLE ELECTROMECHANICAL CONVERTER

2021 ◽  
Vol 1 (161) ◽  
pp. 328-333
Author(s):  
O. Tymofieieva

The article presents a mathematical model of the thermal field for determining the values of temperatures during the submersible electromechanical converter operation. The influence of obtained temperature values on the safety and reliability of the submersible electromechanical converter is analyzed. In a submersible electromechanical converter the windings temperature has great importance. On the one hand, the windings temperature must be such as to transfer a sufficient amount of heat to the viscous loading environment for its processing (movement, transportation, etc.) to begin. On the other hand, the windings temperature must not exceed the limit values for the corresponding insulation class, since this can cause an emergency (fire, short circuit, etc.) The obtained results shows, that temperature on the surface of rotor's cylinders reaches 135 ° C, which provides rapid heating of a viscous substance, and therefore high performance of the pumping process. In this work, the bitumen BND 200/300 was used as the loading and cooling environment. The flash point of this brand of bitumen is 220 ° C and characterizes the degree of flammability of bitumen when it heated. Bitumen does not reach the maximum allowable temperature as a result of heating by means of submersible electromechanical converter that creates a safe temperature corridor in a technological chain at its processing. The temperature of the outer surface of the submersible electromechanical converter, with which the service technical staff may have a contact, does not exceed 20 ° C (Fig. 3), which is completely safe and does not endanger the workers health or life. Also, the obtained temperatures values are within the permissible limits of the heat resistance class of a winding electrical insulating material (H - 180 ° C), which also contributes to the safe submersible electromechanical converter operation.

Energies ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 5986
Author(s):  
Tao Chen ◽  
Hao Guo ◽  
Leiming Yu ◽  
Tao Sun ◽  
Anran Chen ◽  
...  

Si/PEDOT: PSS solar cell is an optional photovoltaic device owing to its promising high photovoltaic conversion efficiency (PCE) and economic manufacture process. In this work, dopamine@graphene was firstly introduced between the silicon substrate and PEDOT:PSS film for Si/PEDOT: PSS solar cell. The dopamine@graphene was proved to be effective in improving the PCE, and the influence of mechanical properties of dopamine@graphene on solar cell performance was revealed. When dopamine@graphene was incorporated into the cell preparation, the antireflection ability of the cell was enhanced within the wavelength range of 300~450 and 650~1100 nm. The enhanced antireflection ability would benefit amount of the photon-generated carriers. The electrochemical impedance spectra test revealed that the introduction of dopamine@graphene could facilitate the separation of carriers and improve the junction quality. Thus, the short-circuit current density and fill factor were both promoted, which led to the improved PCE. Meanwhile, the influence of graphene concentration on device performances was also investigated. The photovoltaic conversion efficiency would be promoted from 11.06% to 13.15% when dopamine@graphene solution with concentration 1.5 mg/mL was applied. The achievements of this study showed that the dopamine@graphene composites could be an useful materials for high-performance Si/PEDOT:PSS solar cells.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Zhenrong Jia ◽  
Shucheng Qin ◽  
Lei Meng ◽  
Qing Ma ◽  
Indunil Angunawela ◽  
...  

AbstractTandem organic solar cells are based on the device structure monolithically connecting two solar cells to broaden overall absorption spectrum and utilize the photon energy more efficiently. Herein, we demonstrate a simple strategy of inserting a double bond between the central core and end groups of the small molecule acceptor Y6 to extend its conjugation length and absorption range. As a result, a new narrow bandgap acceptor BTPV-4F was synthesized with an optical bandgap of 1.21 eV. The single-junction devices based on BTPV-4F as acceptor achieved a power conversion efficiency of over 13.4% with a high short-circuit current density of 28.9 mA cm−2. With adopting BTPV-4F as the rear cell acceptor material, the resulting tandem devices reached a high power conversion efficiency of over 16.4% with good photostability. The results indicate that BTPV-4F is an efficient infrared-absorbing narrow bandgap acceptor and has great potential to be applied into tandem organic solar cells.


2021 ◽  
Vol 11 (15) ◽  
pp. 6736
Author(s):  
Ong Heo ◽  
Yeowon Yoon ◽  
Jinung Do

When underground space requires excavation in areas below the water table, the foundation system suffers from buoyancy, which leads to the uplifting of the superstructure. A deep foundation system can be used; however, in cases where a hard layer is encountered, high driving forces and corresponding noises cause civil complaints in urban areas. Micropiles can be an effective alternative option, due to their high performance despite a short installation depth. Pressurized grouting is used with a packer to induce higher interfacial properties between micropile and soil. In this study, the field performance of micropiles installed using gravitational grouting or pressure-grouted using either a geotextile packer or rubber packer was comparatively evaluated by tension and creep tests. Micropiles were installed using pressure grouting in weak and fractured zones. As results, the pressure-grouted micropiles showed more stable and stronger behaviors than ones installed using the gravitational grouting. Moreover, the pressure-grouted micropile installed using the rubber packer showed better performance than the one using the geotextile packer.


Catalysts ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 163
Author(s):  
Masaru Ogura ◽  
Yumiko Shimada ◽  
Takeshi Ohnishi ◽  
Naoto Nakazawa ◽  
Yoshihiro Kubota ◽  
...  

This paper introduces a joint industries–academia–academia research project started by researchers in several automobile companies and universities working on a single theme. Our first target was to find a zeolite for NH3-SCR, that is, zeolite mining. Zeolite AFX, having the same topology of SSZ-16, was found to be the one of the zeolites. SSZ-16 can be synthesized by using an organic structure-directing agent such as 1,1′-tetramethylenebis(1-azonia-4-azabicyclo[2.2.2]octane; Dab-4, resulting in the formation of Al-rich SSZ-16 with Si/Al below five. We found that AFX crystallized by use of N,N,N′,N′-tetraethylbicyclo[2.2.2]oct-7-ene-2,3:5,6-dipyrrolidinium ion, called TEBOP in this study, had the same analog as SSZ-16 having Si/Al around six and a smaller particle size than SSZ-16. The AFX demonstrated a high performance for NH3-SCR as the zeolitic support to load a large number of divalent Cu ionic species with high hydrothermal stability.


Genetics ◽  
2003 ◽  
Vol 165 (4) ◽  
pp. 2269-2282
Author(s):  
D Mester ◽  
Y Ronin ◽  
D Minkov ◽  
E Nevo ◽  
A Korol

Abstract This article is devoted to the problem of ordering in linkage groups with many dozens or even hundreds of markers. The ordering problem belongs to the field of discrete optimization on a set of all possible orders, amounting to n!/2 for n loci; hence it is considered an NP-hard problem. Several authors attempted to employ the methods developed in the well-known traveling salesman problem (TSP) for multilocus ordering, using the assumption that for a set of linked loci the true order will be the one that minimizes the total length of the linkage group. A novel, fast, and reliable algorithm developed for the TSP and based on evolution-strategy discrete optimization was applied in this study for multilocus ordering on the basis of pairwise recombination frequencies. The quality of derived maps under various complications (dominant vs. codominant markers, marker misclassification, negative and positive interference, and missing data) was analyzed using simulated data with ∼50-400 markers. High performance of the employed algorithm allows systematic treatment of the problem of verification of the obtained multilocus orders on the basis of computing-intensive bootstrap and/or jackknife approaches for detecting and removing questionable marker scores, thereby stabilizing the resulting maps. Parallel calculation technology can easily be adopted for further acceleration of the proposed algorithm. Real data analysis (on maize chromosome 1 with 230 markers) is provided to illustrate the proposed methodology.


2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Zhuang Hui ◽  
Ming Xiao ◽  
Daozhi Shen ◽  
Jiayun Feng ◽  
Peng Peng ◽  
...  

Abstract With the increase in the use of electronic devices in many different environments, a need has arisen for an easily implemented method for the rapid, sensitive detection of liquids in the vicinity of electronic components. In this work, a high-performance power generator that combines carbon nanoparticles and TiO2 nanowires has been fabricated by sequential electrophoretic deposition (EPD). The open-circuit voltage and short-circuit current of a single generator are found to exceed 0.7 V and 100 μA when 6 μL of water was applied. The generator is also found to have a stable and reproducible response to other liquids. An output voltage of 0.3 V was obtained after 244, 876, 931, and 184 μs, on exposure of the generator to 6 μL of water, ethanol, acetone, and methanol, respectively. The fast response time and high sensitivity to liquids show that the device has great potential for the detection of small quantities of liquid. In addition, the simple easily implemented sequential EPD method ensures the high mechanical strength of the device. This compact, reliable device provides a new method for the sensitive, rapid detection of extraneous liquids before they can impact the performance of electronic circuits, particularly those on printed circuit board.


2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Shruti Vashist ◽  
M. K. Soni ◽  
P. K. Singhal

Rotman lenses are the beguiling devices used by the beamforming networks (BFNs). These lenses are generally used in the radar surveillance systems to see targets in multiple directions due to its multibeam capability without physically moving the antenna system. Now a days these lenses are being integrated into many radars and electronic warfare systems around the world. The antenna should be capable of producing multiple beams which can be steered without changing the orientation of the antenna. Microwave lenses are the one who support low-phase error, wideband, and wide-angle scanning. They are the true time delay (TTD) devices producing frequency independent beam steering. The emerging printed lenses in recent years have facilitated the advancement of designing high performance but low-profile, light-weight, and small-size and networks (BFNs). This paper will review and analyze various design concepts used over the years to improve the scanning capability of the lens developed by various researchers.


2014 ◽  
Vol 555 ◽  
pp. 665-672
Author(s):  
Adriana Şerban Târgoveţ ◽  
Dragoş Ionescu-Bondoc

During swimming competitions starting from the block-start platform, a potential hypothesis was noticed, through an active multimodal process, which can make the swimming start efficient, especially in the case of sprint races, by improving the propulsive force parameters of the inferior limbs. The swimming start research from interdisciplinary perspective: biomechanical, kinematic, informational and statistical can consolidate and improve the specific technique in accordance with the abilities and psycho-motor qualities of the swimmers. The present study is based on an experiment where the spatial-temporal and kinematic parameters were processed with the help of a Dartfish program. The evolution of parameters is researched as a result of a motor training program with the purpose to increase the propulsive force off the block-start. The improvement of spatial-temporal parameters influences the performance and evolution of technical parameters. Initial and final recordings were made on an MLD Station Evo5 and MLD software MuskelLeistungs Diagnose, fromSPSport, SPSportdiagnosegeräte, in order to evaluate the force, the power and the propulsive force. The argumentation of the experimental research is based on the statement: “the spatial characteristics of the motions and actions can be studied for themselves as parameters, characteristics or as a reference method for defining other characteristics, such as velocity or push-off force [1]. The main purpose of this study is to identify the influences of the specific start training upon the force improvement and kick power of the support foot from the block-start, during the classic track start. Given that the track start technique is the same as the one of the kick start executed from the international block-start of Omega, OSB11, developed in 2009, one assumes that the improvement of the classic track start leads by default to the improvement of the kick start. Lack of training to practice this type of start leads to deficient use during competitions, thus obtaining poor performances. There are no kick block-starts in Romania in order to train high performance athletes participating in international competitions and as a consequence, poor results are obtained at sprint races. One assumes that training for this type of start can be succesfully made only from a block-start similar to the kick one. The block-start model adapted by us under the same biomechanical conditions as the ones of the international kick start, is called “athletic kick”. The training specific to the kick start is carried out only with the optimum use of the kick block-start, the reasons for this being presented by N, Houel, A. Charliac, JL.Rey, Phellardin the paper: “How the swimmer could improve his track start using new Olympic plot” [2].


2013 ◽  
Vol 554-557 ◽  
pp. 264-273 ◽  
Author(s):  
Stanislav Dedov ◽  
Gunter Lehmann ◽  
Rudolf Kawalla

Due to the constant development in the automotive industry, where high performance shared with the maximal comfort and safety at low car body weight are the primary goals, gains the lightweight construction in importance. Materials with light weight, high strength and toughness are being engaged. With this background the material aluminum and its alloys become highly attractive to manufacturers. There are mainly two ways of forming the metal materials: casting or forming. Apart from substitution of one method by another there are also many examples of combining of casting and forging processes in practice. Such approach allows using the advantages of both methods, shortening the process chains and saving energy and resources at the same time. Furthermore the form flexibility can be increased and the product quality can be improved. For higher process efficiency a direct transition from casting to forging operation should be applied, so that the heat loss decreases and no additional heat treatment between these operations is necessary. There are processes known, which allow producing the final parts by casting and forging from one a single heat. The application of such processes requires materials, which have simultaneously good casting and forging properties. The Institute of Metal forming TU Freiberg works intensively on development of combined casting-forging technologies for lightweight aluminum parts. A technological chain for this coupled process followed by precipitation hardening heat treatment was developed (Figure 1). Heat treatable aluminum cast and wrought alloys with 1 – 7 % silicon were applied. By the variation of silicon content the optimal cast, forging and hardening properties were achieved. This technology with high energy efficiency allows producing durable light weight parts from aluminum alloys while the mechanical properties of the final parts are equal to or even higher than those in the conventional processes.


Author(s):  
S. Sadasivan ◽  
R. Rele ◽  
J. S. Greenstein ◽  
A. K. Gramopadhye ◽  
J. Masters ◽  
...  

The human inspector performing visual inspection of an aircraft is the backbone of the aircraft inspection process, a vital element in assuring safety and reliability of an air transportation system. Training is an effective strategy for improving their inspection performance. A drawback of present-day on-the-job (OJT) training provided to aircraft inspectors is the limited exposure to different defect types. Previous studies have shown offline feedback training using virtual reality (VR) simulators to be effective in improving visual inspection performance. This research aims at combining the advantages of VR technology that includes exposure to a wide variety of defects and the one-on-one tutoring approach of OJT by implementing a collaborative virtual training environment. In an immersive collaborative virtual environment (CVE), avatars are used to represent the co-participants. In a CVE, information of where the trainer is pointing can be provided to a trainee as visual deictic reference (VDR). This study evaluates the effectiveness of simulating on-the-job training in a CVE for aircraft inspection training, providing VDR slaved to a 3D mouse used by the trainer for pointing. The results of this study show that the training was effective in improving inspection performance.


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