Performance tests and simulations for Taiji-1 inertial sensor

Author(s):  
Jian Min ◽  
Jun-Gang Lei ◽  
Yun-Peng Li ◽  
Dong-Xue Xi ◽  
Wen-Ze Tao ◽  
...  

Taiji-1 satellite was successfully launched on 31 August 2019, and it has been operating normally in orbit until now. A series of in-orbit experiments were carried out with the inertial sensor, which included the micro-thrust test, drag-free control test and laser interferometer test. Comprehensive performance simulations and tests of the inertial sensor were also carried out prior to the launch of Taiji-1, including the calibration and drop-tower tests. These tests were one of the preconditions for the success of these experiments. The calibration experiments were conducted in a cave-lab using the gravity-inclination method and the scale factors of the inertial sensor along Y- and Z-axis were measured. In addition, 20 drop-tower tests were carried out in the National Microgravity Laboratory of China (NMLC) drop tower and the control stability of all the axes was tested and optimized. A simulation model was used before each test, and the results showed that an accurate simulation prior to each experiment had an important role in ensuring the efficiency and accuracy of the experiment. The circuit-gain switch was realized for the first time during the drop-tower tests. The test results indicated that the microgravity level of the NMLC drop tower could reach about 13 [Formula: see text]g0 along the horizontal axes, offering an important reference for researchers planning to conduct microgravity experiments in the NMLC drop tower.

Sensors ◽  
2021 ◽  
Vol 21 (6) ◽  
pp. 2203
Author(s):  
Antal Hiba ◽  
Attila Gáti ◽  
Augustin Manecy

Precise navigation is often performed by sensor fusion of different sensors. Among these sensors, optical sensors use image features to obtain the position and attitude of the camera. Runway relative navigation during final approach is a special case where robust and continuous detection of the runway is required. This paper presents a robust threshold marker detection method for monocular cameras and introduces an on-board real-time implementation with flight test results. Results with narrow and wide field-of-view optics are compared. The image processing approach is also evaluated on image data captured by a different on-board system. The pure optical approach of this paper increases sensor redundancy because it does not require input from an inertial sensor as most of the robust runway detectors.


2020 ◽  
Vol 2 (Supplement_3) ◽  
pp. ii22-ii22
Author(s):  
Yoshiki Arakawa ◽  
Junko Suga ◽  
Yukinori Terada ◽  
Kohei Nakajima ◽  
Masahiro Tanji ◽  
...  

Abstract Objective: Kyoto University Hospital has introduced the cancer genomic profiling tests, Oncoprime in 2015, Guardant360 in 2018, which are not under insurance coverage, FoundationOne CDx(F1CDx) and OncoGuide NCC Oncopanel system(NCC OP) in 2019, which received approval for insurance coverage for the first time in Japan. We investigated the results of cancer genomic profiling test under insurance coverage in our hospital. Methods: A special facility for the cancer genomic profiling tests was produced. To perform the cancer genomic profiling test, an outpatient must visit the facility three times (learning, ordering of the test, and getting the results). The expert panels decide the final test results and treatment options with the all information of the patients. Results: From November 2019 to March 2020, 51 and 9 patients were tested with F1CDx and NCC OP, respectively. 16 patients (31%) of F1CDX and 2 patients (22%) of NCC OP got treatment recommendations from the expert panels. However, only 5 patients (9.8%) of F1CDX and 1 patient (11%) of NCC OP received the treatments. The secondary finding suspecting germline mutations was found in 8 patients of F1CDX. Conclusion: After the approval the cancer genomic profiling tests with insurance coverage in Japan, it becomes easy for the patients to perform the test and get the genetic information of the tumor. However, it remains not easy to receive the recommended drugs because of several limitations of their usages.


2019 ◽  
Vol 946 ◽  
pp. 380-385
Author(s):  
Boris A. Chaplygin ◽  
Viacheslav V. Shirokov ◽  
Tat'yana A. Lisovskaya ◽  
Roman A. Lisovskiy

The strength of abrasive wheels is one of the key factors affecting the performance of abrasive machining. The paper discusses ways to improve the strength of abrasive wheels. The stress-state mathematical model presented herein is a generalization of the existing models. It is used herein to find for the first time that there are numerous optimal combinations of the elastic modulus and reinforcing material density, which result in the same minimum value of the objective function. It is found out that increasing the radius of the reinforcing component while also optimizing the mechanical properties of its material may increase the permissible breaking speed of the wheel several times. We herein present a regression equation and a nomogram for finding the optimal combination of control factors. Conventional methods for testing the mechanical properties of materials, which have been proven reliable for testing metals and alloys, are not as reliable for testing abrasive materials, as the test results they generate are not sufficiently stable or accurate. We therefore propose an alternative method that does not require any special equipment or special studies.


2021 ◽  
Vol 64 (4) ◽  
pp. 1381-1389
Author(s):  
Fengwei Gu ◽  
Meng Yang ◽  
Zhichao Hu ◽  
Yanhua Zhang ◽  
Chong Zhang ◽  
...  

HighlightsAn efficient method for separating peanut seedlings and residual film harvested from film-mulched peanut was proposed, and the mechanism was optimized.The relationships between the suspension velocity and moisture content of different shredded materials were studied.Four-factor, three-level Box-Behnken experiments were carried out and analyzed, and the optimal parameter combination was determined.A validation test was carried out to verify the rationality and accuracy of the optimized regression model.Abstract. To address the problems of lower residual film removal and higher material loss in the forage utilization of peanut seedlings wrapped in residual film, this study explored the relationships between the suspension velocity and moisture content of different shredded materials derived from peanut seedlings and conducted performance tests and parameter optimization for a machine that uses peanut seedlings as forage material. Four-factor, three-level Box-Behnken experiments were designed using the rotational speeds of the shredding shaft, upper fans, and lower fans and the frequency of the vibrating sieve as test factors, and using the residual film removal rate and material loss rate as response values. The test results indicated that the suspension velocity of the shredded materials showed a quadratic relationship with moisture content. The performance tests showed that the significance sequence of the test factors for the residual film removal rate was: rotational speed of the lower fans, rotational speed of the upper fans, rotational speed of the shredding shaft, and frequency of the vibrating sieve. The significance sequence for the material loss rate was: rotational speed of the lower fans, rotational speed of the shredding shaft, frequency of the vibrating sieve, and rotational speed of the upper fans. The parameter optimization and validation test showed that the residual film removal rate was 92.71% and the material loss rate was 8.19% when the rotational speeds of the shredding shaft, upper fans, and lower fans were 1650, 770, and 665 rpm, respectively, and the frequency of the vibrating sieve was 4 Hz. The relative errors between the validation test results and the predicted values from the regression models were less than 3%, which suggests that the regression models are reliable. This study provides a reference for the forage utilization of peanut seedlings harvested from film-mulched peanut and provides a reference for determining the optimal working parameters of forage processing machines. Keywords: Agricultural machinery, Box-Behnken experiment, Optimization, Peanut film-seedling separation, Suspension velocity.


1983 ◽  
Vol 73 (6A) ◽  
pp. 1895-1902
Author(s):  
Gerard C. Pardoen

Abstract The ambient vibration test results conducted on the Imperial County Services Building prior to the 15 October 1979 Imperial Valley earthquake are summarized. These results are of significant interest because the Imperial County Services Building has been the source of many postearthquake investigations due to the fact that the 1979 earthquake represented the first time a building instrumented with strong motion recorders suffered and recorded the major structural failure.


1975 ◽  
Vol 69 (8) ◽  
pp. 350-353
Author(s):  
John L. Morse

The most common question asked by the psychologist who is faced for the first time with assessing a visually handicapped child are answered. The 15 questions include such areas as the required information concerning visual condition, background of the client, test conditions, the role of the parents, classroom observation, behaviors observed during testing, evaluation of test results, expectations of parents and teachers, and modification of a child's inappropriate behaviors.


2016 ◽  
Vol 15 (3) ◽  
pp. 7-14 ◽  
Author(s):  
M. A. Koroleva ◽  
I. S. Koroleva ◽  
I. M. Zakroeva ◽  
I. M. Gruber

Relevance. One of the prognostic criteria meningococcal infection (MI) epidemic status process is the increasing number of resistant to antibiotics meningococcal strains. Aim of this study was to investigate the dynamics of invasive strains of N. meningitidis susceptibility to antibiotics in Moscow in 2006 - 2015. Materials and methods. Studied 98 strains of N. meningitidis, isolated from blood and cerebrospinal fluid of patients with MI. The study changes of sensitivity N. meningitidis to antibiotics was occured in two periods: first -2006 - 2011 and second - 2012 - 2015. The MIC was determined by E-test. Results. In the present study revealed for the first time the Russian strains of N. meningitidis, moderately resistant to penicillin (5 strains) and resistant to rifampicin (3 strains). Among the studied strains were not found resistant to ceftriaxone, ciprofloxacin, tetracycline and chloramphenicol. Discussion. Comparison results two study periods allowed to reveal the dynamics of increasing the sensitivity of N. meningitidis to antibiotics, which confirms the decline in meningococcal virulence, and as a result, continued interepidemic MI period. Conclusions. Despite the decline antibakterial resistance is required continuous monitoring.


Author(s):  
Natalia Lvovna Margolina ◽  
Irina Vladimirovna Nalimova

The article analyzes the concept of mathematical literacy. The formation of mathematical literacy among members of modern society is a fundamental basis for the formation of functional literacy. Currently, there is no single approach to the interpretation of the concept of "mathematical literacy", the article provides several different approaches to the definition. Based on the analysis of the points of view of different scientists, the authors of the article highlight the main components of the concept of "mathematical literacy". These include: literacy of mathematical speech; possession of mathematical concepts; the ability to correctly formulate definitions and statements; the ability to apply mathematics to research. The paper provides a characteristic of the listed components of mathematical literacy. In addition, in this work, for the first time, an attempt was made to formulate the levels of mathematical literacy – speech, terminological, critical and operational. The article presents the results of testing students in pedagogic areas of training of two universities – Kostroma State University and Yaroslavl State Pedagogic University. The test was aimed at assessing the level of mathematical literacy of future teachers, for whom teaching mathematics will be a part of their professional activities. The test tested not only the knowledge of terms and the ability to give definitions, but also the ability to correctly apply mathematics to solve practical problems with subsequent interpretation, as well as the ability to see errors and inaccuracies in the texts of students' works, Internet sources and teaching aids. The authors identified criteria for assessing the test results and for each criterion; a quantitative indicator was determined equal to the number of correctly completed tasks. The low results of even third-year students show topicality of specific activities that could help improve the mathematical literacy of pedagogues.


2021 ◽  
Author(s):  
Rasoul Alipour

Abstract Existing problematic sub-layers in mixing technologies are a challenge, and for the first time, the effects of salt sub-layers in mass mixing technology have been investigated in this study for sandy salt in the southwest of Iran. This paper discusses the influence of adding various cement contents, Aw, and imposing different preloading values on the salty sand soil. First, salt and sand samples were dried, then, 90 % sand was mixed with 10% salt. After that, 30 % water was mixed thoroughly with the mixture of salty sand to obtain slurries. Cement slurry at a water-cement ratio (w/c) of 0.6 was then added to the sample and thoroughly mixed. The amount of cement in a slurry form that was added to the salty soil was 2, 4, 6, 8, and 10% by mass of dry soil. Each treated soil preloaded by 0, 9, and 45 kPa. After 120 days, the unconfined compressive strength of the sample was determined. Furthermore, by Scanning Electronic Microscope, SEM, the microstructures of treated samples were analyzed. At the end Unconfined Compression Strength, UCS, test results normalized to the non-preloaded treated soil. By increasing cement content, the effect of preloading in increasing UCS will decrease. In the SEM images for Aw=2%, the effect of preloading indicates porous shape for non-preloaded samples. Vice versa by Aw=8%, porous shape in the SEM images will disappear. In the end, treatability studies of pure salt in the thick layer have been investigated.


2021 ◽  
Author(s):  
◽  
Jan Larres

<p>In order to evaluate software performance and find regressions, many developers use automated performance tests. However, the test results often contain a certain amount of noise that is not caused by actual performance changes in the programs. They are instead caused by external factors like operating system decisions or unexpected non-determinisms inside the programs. This makes interpreting the test results hard since results that differ from previous results cannot easily be attributed to either genuine changes or noise. In this thesis we use Mozilla Firefox as an example to try to find the causes for this performance variance, develop ways to reduce the noise and present a statistical technique that makes identifying genuine performance changes more reliable. Our results show that a significant amount of noise is caused by memory randomization and other external factors, that there is variance in Firefox internals that does not seem to be correlated with test result variance, and that our suggested statistical forecasting technique can give more reliable detection of genuine performance changes than the one currently in use by Mozilla.</p>


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