scholarly journals Very Fast Current Diagnostic for Linear Pulsed Beams

2018 ◽  
Vol 167 ◽  
pp. 02006
Author(s):  
Vincenzo Nassisi ◽  
Domenico Delle Side ◽  
Vito Turco

Fast current pulses manage lasers and particle accelerators and require sophisticate systems to be detected. At today Rogowski coils are well known. They are designed and built with a toroidal structure. In recently application, flat transmission lines are imploded and for this reason we develop a linear Rogowski coil to detect current pulses inside flat conductors. To get deep information from the system, it was approached by means of the theory of the transmission lines. The coil we build presents a resistance but it doesn’t influence the rise time of the response, instead the integrating time. We also studied the influence of the magnetic properties of coil support. The new device was able to record pulses of more hundred nanoseconds depending on the inductance, load impedance and resistance of the coil. Furthermore, its response was characterized by a sub-nanosecond rise time (~100 ps), The attenuation coefficient depends mainly on the turn number of the coil, while the quality of the response depends both on the manufacture quality of the coil and on the magnetic core characteristics. In biophysical applications often, a double line is employed in order to have a sample as control and a sample stressed by a light source. So, in this case we build two equal plane lines by 100 Ω characteristic resistance connected in parallel. We diagnosed the current present in a line. The attenuation factor resulted to be 11,5 A/V.

JURNAL ELTEK ◽  
2020 ◽  
Vol 18 (2) ◽  
pp. 48
Author(s):  
Achmad Afandi ◽  
Mila Fauziyah Fauziyah ◽  
Denda Dewatama

Perusahaan tahu di Indonesia pada umumnya, masih menggunakan cara manual, dalam pembuatannya khususnya pada proses penyaringan bubur kedelai yang membutuhkan waktu yang, lama. Hal tersebut didasarkan pada belum ditemukannya mesin pemeras bubur kedelai. Dewasa ini telah ditemukan inovasi mesin, pemeras bubur kedelai yang bisa meningkatkan kuantitas dan, kualitas produksi dibanding dengan cara manual. Penerapan, teknologinya adalah bubur kedelai diletakkan pada tabung, penyaring kemudian tabung tersebut diputar menggunakan motor, yang dihubungkan melalui fanbelt dan pulley. Ketika motor, diputar, tabung akan ikut berputar sehingga menimbulkan gerak, sentrifugal dimana air kedelai akan terpisah dari ampas. Kecepatan putar motor yang dikontrol adalah 750 rpm dengan, nilai Kp 0,108 , Ki 0,83 sehingga mendapatkan air sari kedelai, sebesar 1,3 liter dengan perbandingan 1 kg kedelai : 1 liter air. Parameter dari penerapan metode PI ini meliputi rise time 4 detik, settling time 4,5 detik, overshoot 0 dan error steady state 2,4%. Dengan penerapan metode PI maka hasil perasan kedelai dari, peyaringan menjadi semakin banyak dan waktu yang dibutuhkan 4 menit lebih singkat dibandingkan dengan cara konvensional.   Tofu companies in Indonesia generally still use manual methods in their manufacture, especially in the soybean slurry screening process which certainly has many disadvantages such as extortion time needed. This was based on the fact that there was no innovation in the soybean pulp squeezer. Currently, it has been found that innovations of soybean slurry machines can increase the quantity and quality of production compared to manual methods. The application of the technology is soybean slurry placed on the filter tube then the tube is rotated using a motor connected with fanbelt and pulley. When the motor is rotated, the tube will rotate, causing centrifugal motion where the soybean water will separate from the pulp. The speed of the motor controlled in 750 rpm with the Kp 0,108, Ki 0,83, to get soybean essence up to 1,3 liter within comparison 1 kg soybean : 1 liter water. The parameter PI method including rise time 4 second, settling time 4,5 second, overshoot 0 and error steady state 2,4%. By applying PI method, the result of filtering is 4 minute faster comparing with conventional method.


2009 ◽  
Vol 87-88 ◽  
pp. 244-249
Author(s):  
Zhi Hua Li ◽  
Shi Liang Yang ◽  
Peng Xia ◽  
Zhao Feng Li ◽  
Yan Qing Liu ◽  
...  

By analyzing the technology process of all steel radial truck tire building machine, the author finds that there is a big potential of improvement both in stitching effect and efficiency. A new kind of stitching and control device is designed to replace the original. The new device can realize the soft stitching of tire, which reduces redundant actions and thus optimizes the process and improves the stitching efficiency. It is found in tests that the optimized process reduces the blister defectives greatly. Both productivity and quality of tires are improved significantly. It shows a big economic benefit.


Author(s):  
Lunnetta Safura Lumba ◽  
◽  
Suwarno Suwarno ◽  

In recent years, polymeric insulators have been increasingly used for high voltage overhead transmission lines. The industry has replaced the insulators from ceramic to polymeric due to its lightweight and hydrophobic materials, not to mention the performance against pollutant contamination. In this study, an analysis of two 70 kV silicone rubber insulators is performed. The insulators had been in service for 30 years on transmission networks in volcanic area, exposed to intense UV solar radiation in midday, but also high precipitation occur throughout the year. The urge to understand better of polymeric aging behavior is important to improve the quality of the polymeric type insulators. In this study, these aged samples were then compared with virgin samples to identify the endurance and quality of polymer material. The surface deterioration and the change of chemical content were evaluated using advanced techniques, including Spectroscopy and Scanning Electron Microscopy (SEM), Energy-dispersive X-ray Analysis (EDX), Thermo-Gravimetric Analysis (TGA), and Fourier Transform Infrared (FTIR). Meanwhile, the hydrophobic and visual inspection were also conducted. The hydrophobicity was evaluated by measuring the contact angle and assessed using IEC62073. The aged samples are categorized as hydrophobic class 1 due to the angle value of more than 60o. Physicochemical results showed that the aged sample compared with the virgin simple did not differ significantly given that the aged samples have been in-service for 30 years. Based on TG/DTA result, the percentage difference of weight loss between virgin and aged sample only lower than 4%. Then, from EDX result, the atomic percentage differences of C and O component compared with virgin sample are 4%-10%. Furthermore, the FTIR spectra indicates a normal aging condition of the silicone rubber, the difference in peak value of Si-(CH3)2 and OH compared with virgin sample is 10%.


Materials ◽  
2020 ◽  
Vol 13 (8) ◽  
pp. 1982 ◽  
Author(s):  
Marco Cicciù ◽  
Luca Fiorillo ◽  
Cesare D’Amico ◽  
Dario Gambino ◽  
Emanuele Mario Amantia ◽  
...  

The advent of new technologies in the field of medicine and dentistry is giving improvements that lead the clinicians to have materials and procedures able to improve patients’ quality of life. In dentistry, the last digital techniques offer a fully digital computerized workflow that does not include the standard multiple traditional phases. The purpose of this study is to evaluate all clinical trials and clinical randomized trials related to the digital or dental impression technique in prosthetic dentistry trying to give the readers global information about advantages and disadvantages of each procedure. Data collection was conducted in the main scientific search engines, including articles from the last 10 years, in order to obtain results that do not concern obsolete impression techniques. Elsevier, Pubmed and Embase have been screened as sources for performing the research. The results data demonstrated how the working time appears to be improved with digital workflow, but without a significant result (P = 0.72596). The papers have been selected following the Population Intervention Comparison Outcome (PICO) question, which is related to the progress on dental impression materials and technique. The comparison between dentists or practitioners with respect to classic impression procedures, and students open to new device and digital techniques seem to be the key factor on the final impression technique choice. Surely, digital techniques will end up supplanting the analogical ones altogether, improving the quality of oral rehabilitations, the economics of dental practice and also the perception by our patients.


1997 ◽  
Vol 15 (2) ◽  
pp. 241-248 ◽  
Author(s):  
H. Chuaqui ◽  
E. Wyndham ◽  
C. Friedli ◽  
M. Favre

The design and constructional aspects of a novel pulse power generator for use in dense plasma research presently under construction are presented. The generator consists of two Marx capacitor banks, each of 0.25 μF, 480 kV, and 28.8 kJ. Each Marx generator drives a water transmission line, in which the live electrode is the central conductor. The transmission lines consist of a constant impedance section followed by a multielectrode gas linegap followed by an exponential taper to the load section. The novel feature is the use of an auxiliary exponential line coupled at the load. This line controls both the voltage and the effective impedance at the load section. In addition, by leaving this line circuit open, energy not coupled to the plasma in the initial high-impedance phase may be reflected back and deposited into the discharge, increasing the peak current by 50%. Circuit simulations using a real-time-varying load impedance show that the current pulse rises in an approximately linear way to a maximum of 1.2 MA at 250 ns. The current falls to zero in the following 250 ns. The current waveform may be flattened simply by disconnecting the auxiliary line, giving a rectangular pulse of 350 ns with a maximum value of 950 kA. The overall impedance of the entire system may be adjusted by varying the separation between the conductors. The equivalent source impedance at the load is 0.8 Ω. This low value is by virtue of the auxiliary line, which limits the voltage at the load section and reduces the insulator constraints. We present simulations of the generator under real load conditions. The model also is checked against analytical solutions of exponential line behavior and against other published models of pulse power generators.


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