Analysis of decay characteristics of an accumulator in an open-circuit hydrostatic system with pump loading

2017 ◽  
Vol 231 (4) ◽  
pp. 312-326 ◽  
Author(s):  
Ajit Kumar ◽  
K Dasgupta ◽  
J Das
Keyword(s):  
Open Circuit ◽  
Drive System ◽  
Test Results ◽  
System Pressure ◽  
Parametric Studies ◽  
Resistive Loads ◽  
Hydraulic Accumulator ◽  
Hydrostatic System ◽  
Mining Vehicles ◽  
Made In

The effects of the decay characteristics of a hydraulic accumulator on the responses of the hydrostatic drive system used in mining vehicles are studied in this article. The system considered for the analysis basically consists of a hydraulic pump, hydro-motor, accumulator and a loading circuit. The studies have been carried out with respect to two different sizes of accumulators. The system model has been made in MATLAB/Simulink® environment. The simulation test results are obtained with respect to the hydro-motor speeds and the system pressure at different resistive loads and capacities of the accumulator and they are verified with the experimental test data. Using the validated model, the parametric studies are also made on the speed responses of the hydrostatic drive for different precharge pressures of the accumulator and inertial load on the motor shaft. The studies made in this article may be useful for the selection of proper capacity of accumulators incorporated in the hydrostatic drive system in mining vehicles.

ЦИФРОВОЙ ИЗОЛЯТОР В СПЕЦИАЛИЗИРОВАННОМ КОРПУСЕ, ВЫПОЛНЕННОМ ПО ТЕХНОЛОГИИ LTCC

2020 ◽  
Vol 96 (3s) ◽  
pp. 392-395
Author(s):  
В.А. Бутузов ◽  
А.Е. Назаренко ◽  
Н.Ю. Дмитриев ◽  
В.А. Трофимов ◽  
В.А. Косевский ◽  
...  
Keyword(s):  
Low Temperature ◽  
Data Rate ◽  
Test Results ◽  
Made In

Представлены результаты разработки цифрового изолятора на основе интегрального микротрансформатора в специализированном корпусе, выполненном по технологии низкотемпературной совместно обжигаемой керамики (LTCC). Согласно результатам измерений тестовых образцов максимальная скорость передачи данных разработанного цифрового изолятора - не менее 30 Мбит/с. The paper presents the results of the development of a digital insulator based on an integral microtransformer in a specialized package made in technology of low-temperature co-fired ceramics. The isolator is a microassembly consisting of a transceiver chip and an integrated transformer. According to the test results, the maximum data rate speed of the developed digital insulator is not less than 30 Mbit/s.

scholarly journals Deriving formulations for forecasting the ultimate strength of locally dented ring-stiffened cylinders under combined axial compression and radial pressure loads

2020 ◽  
Vol 23 (3) ◽  
pp. 640-654
Author(s):  
Do Quang Thang
Keyword(s):  
Ultimate Strength ◽  
Residual Strength ◽  
Good Accuracy ◽  
Uncertainty Modeling ◽  
Radial Pressure ◽  
Mean Value ◽  
Reduction Factor ◽  
The Novel ◽  
Test Results ◽  
Parametric Studies

Introduction: This paper focuses on the derived equations to evaluate the ultimate strength of ring-stiffened cylinders with local denting damage under combined loadings. The damage generation scenarios in this research are representing the collision accidents of offshore stiffened cylinders with supply ships. Methods: Numerical analysis of structures are performed using Abaqus software after validation against the experiments from the authors. The responses from seventeen cylinder specimens are analyzed to develop the numerical methods. Results: Good accuracy results were achieved when comparing the test results and the simulation results. Parametric studies are then performed on design examples of ring-stiffened cylinders when considering both intact and damaged conditions for assessing the reduction factor. Then, the novel simple design equations to assess the residual strength of ring-stiffened cylinders after ship collision are derived based on the regression analysis. These equations have good accuracy with mean value Xm (Uncertainty modeling factor) around 1.0 and together with COV (Coefficient of Variation) lower than 5.3%. Conclusion: The accuracy and reliability of the derived equations are validated by comparing it with the existing test data in open access. It is concluded that the proposed equations have high accuracy and reliability, and convenient application for the purpose of checking the residual strength of dented offshore cylinder under ship collisions.

scholarly journals Pengembangan Rubrik Penskoran pada Asesmen Otentik untuk Materi Volume dan Luas Balok

2020 ◽  
Vol 4 (2) ◽  
pp. 275
Author(s):  
Yunita Rochmawati Jonan
Keyword(s):  
Authentic Assessment ◽  
Student Response ◽  
Small Scale ◽  
Development Research ◽  
Test Results ◽  
Assessment Of Learning ◽  
Teachers And Students ◽  
Scoring Rubric ◽  
Large Groups ◽  
Made In

ABSTRAK Tujuan penelitian pengembangan ini adalah menghasilkan sebuah rubrik penskoran pada asesmen otentikuntuk materi volume dan luas balok yang dapat digunakan oleh guru dan siswa. Rubrik ini dibuat sesuai dengan standar penilaian dalam kurikulum 2013. Penelitian pengembangan (R&D) ini menggunakan model Borg and Gall yang terdiri dari lima tahap yaitu penelitian dan pengumpulan data awal, perencanaan, pengembangan format produk, uji coba skala kecil, revisi akhir dan penyempurnaan produk. Hasil penelitian pengembangan ini berupa rubrik penyekoran holistik dan analitik dengan nilai sangat valid sebesar 94%. Analisis dari penelitian ini adalah angket kebutuhan bagi guru dan siswa sedangkan uji coba dilakukan melalui perorangan, kelompok kecil dan kelompok besar. Sedangkan kelayakan rubrik penskoran dari penilaian oleh ahli dengan menggunakan angket uji validitas materi, hasil belajar siswa, respon siswa serta tanggapan guru pengajar. Hasil penelitian ini menunjukkan bahwa rubrik penskoran ini efektif dalam membantu memperbaiki hasil ulangan dan cukup praktis serta dapat dipergunakan untuk memberikan penilaian hasil belajar yang sesuai dengan kurikulum 2013. Kata kunci: rubrik, penskoran, asesmen otentik.   ABSTRACT The purpose of this development research is to produce a scoring rubric on an authenticity assessment for the volume and area materials that can be used by teachers and students. The rubric is made in based on the assessment standards in the 2013 curriculum. This development research (R&D) uses the Borg and Gall model consisting of five stages of preliminary data research and collection, planning, product format development, small-scale trials, final revisions and product enhancements. The results of this development research include holistic and analytic scoring rubric with a very valid score of 94%. The rubric is analyzed fromquestionnaire for teachers and students, while trials are conducted through individuals, small groups and large groups. The feasibility of the scoring rubric from assessment by members by using the material validity test questionnaire, student learning results, student response and teacher responses. The results of this study show that the scoring rubric is effective in helping to improve the test results and is practical and can be used to provide assessment of learning outcomes in accordance with the 2013 curriculum. Keywords: rubric, scoring, authentic assessment.

scholarly journals The Effect of Technological Treatments and Loads on the Service Life of Fillet Welds

2020 ◽  
pp. 21-25
Author(s):  
Janusz Lewandowski ◽  
Dariusz Rozumek
Keyword(s):  
Service Life ◽  
Stress Ratio ◽  
Fatigue Cracks ◽  
Constant Stress ◽  
Fillet Welds ◽  
Test Results ◽  
Technological Treatment ◽  
Technological Treatments ◽  
Made In

The paper presents test results concerning the service life of fillet welds made in steel S355. In addition, the article discusses the initiation and growth of fatigue cracks in specimens subjected to bending with torsion. The tests were performed in relation to constant stress ratio R = -1 and 0. The results presented in the article take into account the effect of the technological treatment on the service life of the specimens. The tests revealed longer service life of the specimens not subjected to the technological treatment, both when R = -1 and 0.

scholarly journals The PENGARUH KEMASAN DAN DURABILITY MAKANAN RINGAN BUATAN MALAYSIA TERHADAP ETNOSENTRISME KONSUMEN DI BATAM

2019 ◽  
Vol 4 (1) ◽  
pp. 132
Author(s):  
Tiurniari Purba
Keyword(s):  
Multiple Regression ◽  
Significant Influence ◽  
Research Tool ◽  
Test Results ◽  
F Test ◽  
Statistical Software ◽  
Consumer Ethnocentrism ◽  
Regression Test ◽  
Snack Products ◽  
Made In

This study aims to determine the effect of variable packaging and durability on consumer ethnocentrism in Batam, both partially and simultaneously. The background of this research is due to the rise of types of snack products made in Malaysia circulating in every type of retail in Batam, and very well-selling. This research will be analyzed quantitatively with a research tool using a questionnaire. The results of the questionnaire will be processed with the help of SPSS statistical software. As for what will be tested is the multiple regression test. Regression test results showed that the packaging had no effect on consumer ethnocentrism in Batam. While the durability variable shows a significant influence on consumer ethnocentrism. Simultaneously the F test shows that both packaging and durability affect ethnocentrism. While the determination coefficient test results indicate that the determination test output for the R Square value of 0.817 means that the magnitude of the contribution or contribution of the X1 and X2 variables of 82% to the Y variable and the rest of 18% is the influence of other variables not mentioned in this study.   Keywords: Packeging, Durability, Etnosentrisme, Snack

Test Results and What They Mean

1971 ◽  
Vol 6 (4) ◽  
pp. 429-431
Author(s):  
William J. Woolbright
Keyword(s):  
Academic Achievement ◽  
Los Angeles ◽  
Grade Level ◽  
School Administrators ◽  
Remedial Reading ◽  
School Personnel ◽  
Test Results ◽  
Local School ◽  
Learning Group ◽  
Made In

Part of the responsibility of a reading therapist is to report to the parents the results of specialized programs developed for their children. Whether the report is made in person or sent to the parents or teachers of the children, there can be confusion or misunderstanding when grade-level scores are used. Over a period of time, and after a review of numerous parent conferences and discussions with local school administrators and teachers, the following report was prepared by the Academic Achievement and Learning Group, Los Angeles, California, to better communicate with parents and school personnel who are concerned about students' work in remedial reading.

Design Considerations for Flow Noise in Automotive Air Handling Systems

1999 ◽  
Author(s):  
David W. Warner ◽  
Niranjan G. Humbad ◽  
Basem Alzahabi ◽  
Robert A. Porada
Keyword(s):  
Pressure Drop ◽  
Predictive Model ◽  
Design Process ◽  
Heat Exchangers ◽  
Test Results ◽  
Noise Levels ◽  
Flow Noise ◽  
Design Considerations ◽  
System Pressure ◽  
Noise Data

Abstract Noise from automotive air handling systems is an important issue for driver and passenger comfort. This study was undertaken to quantify the flow noise from the blower and remaining system, and to develop an analytical predictive model for airflow noise. Tests were conducted on four different vehicle Air Handling Systems (AHS) comprised of blower, heat exchangers, ducts and panel registers. Flow and noise data were measured. Test results suggest that overall noise is dominated by blower noise. A predictive model for airflow noise was developed. This model suggests system pressure drop (Δp) and system airflow (q) being dominant parameters in the noise predictions. The noise variation scales as flow velocity to the power 5.75. The developed model for flow noise can be very useful in the design process to estimate noise levels for new systems from CFD/CAE analyses.

scholarly journals Analysis on the Possibility of Eliminating Interference from Paraseismic Vibration Signals Induced by the Detonation of Explosive Materials

Sensors ◽  
2020 ◽  
Vol 20 (21) ◽  
pp. 6401
Author(s):  
Józef Pyra ◽  
Maciej Kłaczyński ◽  
Rafał Burdzik
Keyword(s):  
Acoustic Waves ◽  
Vibration Signal ◽  
Test Results ◽  
Subtraction Method ◽  
Reverberation Chamber ◽  
Explosive Materials ◽  
Short Time ◽  
Spectral Subtraction Method ◽  
The Impact ◽  
Made In

This article presents the results of studies on the impact of acoustic waves on geophones and microphones used to measure airblasts carried out in a reverberation chamber. During the tests, a number of test signals were generated, of which two are presented in this article: frequency-modulated sine (sine sweep) waves in the 30–300 Hz range, and the result of detonating 3 g of pyrotechnic material inside the chamber. Then, based on the short-time Fourier transform, the spectral subtraction method was used to remove unwanted disruption interfering with the recorded signal. Using MATLAB software, a program was written that was calibrated and adapted to the specifics of the measuring equipment based on the collected test results. As a result, it was possible to clean the signals of interference and obtain a vibration signal propagated by the substrate. The results are based on signals registered in the laboratory and made in field conditions during the detonation of explosive materials.

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