Non-Linear Model of Rubber Bearings under Random Excitation

2012 ◽  
Vol 452-453 ◽  
pp. 602-606
Author(s):  
Hai Yan Jing ◽  
Yan Ping Zheng ◽  
Ming Xia Fang
Keyword(s):  
Past Research ◽  
Random Excitation ◽  
Mean Value ◽  
Statistical Characteristics ◽  
The Past ◽  
Non Linear ◽  
The Mean ◽  
Rubber Bearings ◽  
Force Displacement ◽  
Sinusoidal Excitation

Through dynamics test and theoretical analysis about rubber bearings in Auto body’s sub-frame, and the past research results of sinusoidal excitation, a hysteretic non-linear mathematical model of the rubber bearings is established under the condition of random excitation. The model shows that the hysteretic renewed force of the rubber bearings under random excitation can be expressed with the mean value and variance of random excitation’s statistical characteristics and speed. Finally curves of the hysteretic renewed force - displacement are reconstructed with the model built, which match the test’s results well.

scholarly journals Development of Jawi Spelling Skills Mobile Applications, 'Oh Jawiku'

2019 ◽  
Vol 13 (07) ◽  
pp. 80
Author(s):  
Noor Asmina Binti Mohd Rashid ◽  
Shaharuddin Bin Md Salleh ◽  
Norah Binti Md Noor
Keyword(s):  
Mobile Learning ◽  
Mobile Applications ◽  
Mobile Application ◽  
Mean Value ◽  
The Past ◽  
Post Test ◽  
Main Medium ◽  
The Mean ◽  
Addie Model ◽  
Roman Script

<p class="0abstract"> In the past, Jawi script was the main medium of intermediation in Malaya. However, since the emergence of the Roman script, the use of Jawi script has been marginalized causing less awareness among some of the younger generation on the uniqueness of Jawi script. Therefore, a mobile application has been developed to attract students to explore Jawi script especially the spelling of Jawi words. This Jawi Spelling Skills mobile application used constructivism approach and ADDIE model during the development process. This study used quantitative one group pre-test and post-test research design that conducted among 20 students of a primary school. The result shows that the mean value of the post-test was higher than the pre-test which is 89.00 while the percentage of students who liked the Jawi Spelling Skills mobile learning application was high. In conclusion, the application of Jawi Spelling Skills Mobile Learning Application able to attract students to learn Jawi indirectly raised the dignity of Jawi script in the future besides supporting the 21st- century education.</p>

Mean-Square Response of Thermoviscoelastic Medium to Nonstationary Random Excitation

1976 ◽  
Vol 43 (1) ◽  
pp. 150-158 ◽  
Author(s):  
W. Mosberg ◽  
M. Yildiz
Keyword(s):  
Random Excitation ◽  
Irreversible Thermodynamics ◽  
Envelope Function ◽  
Statistical Characteristics ◽  
Mean Square ◽  
Statistical Property ◽  
Step Functions ◽  
Mean Square Response ◽  
The Mean ◽  
Thermoviscoelastic Medium

The mean-square wave response of a lightly damped thermoviscoelastic medium to a special type of nonstationary random excitation is determined. The excitation function on the thermoviscoelastic medium is taken in the form of a product of a well-defined, slowly varying envelope function, and a part which prescribes the statistical characteristics of the excitation. Both the unit step and rectangular step functions are used for the envelope function, and both white noise and noise with an exponentially decaying harmonic correlation function are used to prescribe the statistical property of the excitation. By taking into consideration the slow variation envelope function and the wave characteristics of the lightly damped thermoviscoelastic medium, the mean-square response (as a function of temperature, excitation, and damping parameters with the aid of reversible and irreversible thermodynamics) is evaluated.

scholarly journals Characteristics of cold–warm variation in the Hetao region and its surrounding areas in China during the past 5000 years

2010 ◽  
Vol 6 (4) ◽  
pp. 475-481 ◽  
Author(s):  
M.-Q. Li ◽  
Q.-S. Ge ◽  
Z.-X. Hao ◽  
J.-Y. Zheng ◽  
S.-F. He
Keyword(s):  
Climate Changes ◽  
Mean Value ◽  
Data Series ◽  
Proxy Data ◽  
Average Temperature ◽  
The Past ◽  
The Mean ◽  
Temperature Proxy ◽  
Surrounding Areas

Abstract. Using six long-term temperature proxy data series derived from different natural evidences, including pollens and lake-sediments, we reconstructed a temperature series with a 100-yr time resolution for the past 5000 yr in the Hetao region and its surrounding areas. The resulting series suggests that, on a millennial timescale, temperatures in the region were higher than the mean value of the whole series during the 5000~2600 years before present (yr BP) period, and became relatively low comparing with the average temperature of the whole series after 2600 yr BP. Within these two periods, temperature fluctuations comprising numerous short, multi-centennial intervals also existed. A comparison between our reconstructed series and other series in China and across the Northern Hemisphere indicate that, on a long-term scale, cold–warm variations had been in phase across the whole hemisphere during the past 5000 years; on the century to multi-century scale, the beginning and the ending times varied from region to region, thus implying that climate changes did not occur simultaneously in different regions.

scholarly journals Comparative analysis of maternal mortality indices in Perm Krai over the past 20 years

2018 ◽  
Vol 35 (5) ◽  
pp. 57-62
Author(s):  
M. M. Padrul ◽  
E. V. Cherkasova ◽  
V. V. Skryabina ◽  
S. N. Berseneva
Keyword(s):  
Comparative Analysis ◽  
Maternal Mortality ◽  
Statistical Data ◽  
Federal District ◽  
Mean Value ◽  
Data Intensive ◽  
The Past ◽  
Perm Krai ◽  
The Russian Federation ◽  
The Mean

Aim. To compare the maternal mortality (MM) indices in Perm Krai with MM indices in the Russian Federation (RF) and Privolzhskiy Federal District over the past 20 years. Materials and methods. On the basis of official statistical data, intensive indices and image indices, mean multiyear MM indices, 95 % confidence intervals, median, 25 and 75 percentile indices were calculated. The mean multiyear indices are presented as M (mean value) ± SD (standard deviation). Results. According to official statistical data, the mean multiyear (1997–2016) indices of MM coefficient in Perm Krai tend to decline, but they do not reliably differ from the analogous indices in RF. During the last 20 years, there was noted a steady and obvious decrease in MM index on the territory of Perm Krai, especially marked for the last 2 years (2015–2016) that resulted in appearance of statistically significant differences regarding this index in Perm Krai compared to these indices in RF as a whole. Conclusions. Perm Krai is a rather favorable region as far as rendering of medical aid to pregnant, parturient women and puerperas is concerned.

scholarly journals Relationship between atopic manifestations, family history of atopic disease and cord blood IgE levels in children

2007 ◽  
Vol 47 (6) ◽  
pp. 278
Author(s):  
Tisnasari Hafsah ◽  
Myrna Soepriadi ◽  
Budi Setiabudiawan ◽  
Herry Garna
Keyword(s):  
Family History ◽  
Cord Blood ◽  
Atopic Disease ◽  
Mean Value ◽  
Inclusion Criteria ◽  
Chi Square ◽  
The Past ◽  
History Of ◽  
The Mean ◽  
The Relationship

Background The incidence of atopic disease tends to increaseover the past few decades and its morbidity interferes with thequality of life and health. Prediction of the disease is importantfor early prevention.Objective To evaluate the relationship between atopicmanifestations, family history (FH) of atopic disease and cordblood IgE (CB-IgE) levels.Methods We conducted an analytic observational study withcohort retrospective design on children with an average age of 3years whose CB-IgE had been measured at delivery inKiaracondong Primary Health Care during October–December2004. Manifestations of atopic disease were recorded using ISAACquestionaire for allergy. Chi-square, Mann-Whitney test, andlogistic regression analysis were used for analysis.Results Cord blood IgE was measured on 124 children after birth.Only 94 children (76%) fulfilled the inclusion criteria. Atopicdisease was found in 17 children (18%), consisting of 8 childrenwith atopic dermatitis, 4 with allergic rhinitis, and 5 suffered fromboth. There were significant differences in the mean value of CB-IgE (Z M-W =4.60; P<0.001) and FH (x 2 =19.059; P<0.001)between atopic and non atopic children. Cut off point of the CB-IgE concentration was 1.4 IU/mL (77.7%). The highest probabilityfor atopic manifestations was found in children who had highCB-IgE and positive FH (P=45%). Relative risk of children withhigh CB-IgE level in positive FH group was 3.636 (95% CI0.943;14.016).Conclusion CB-IgE level and family history of atopic disease arerisk factors for the development of atopic manifestation.

scholarly journals Non-Stationary Random Vibration of FE Structures Subjected to Moving Loads

2009 ◽  
Vol 16 (3) ◽  
pp. 291-305 ◽  
Author(s):  
F. Lu ◽  
D. Kennedy ◽  
F.W. Williams ◽  
J.H. Lin
Keyword(s):  
Random Vibration ◽  
High Efficiency ◽  
Harmonic Excitation ◽  
Random Excitation ◽  
Mean Value ◽  
Statistical Characteristics ◽  
Moving Loads ◽  
Precise Integration ◽  
Power Spectral ◽  
Decomposition Procedure

An efficient and accurate FEM based method is proposed for studying non-stationary random vibration of structures subjected to moving loads. The loads are assumed to be a stationary process with constant mean value. The non-stationary power spectral densities (PSD) and the time dependent standard deviations of dynamic response are derived by using the pseudo excitation method (PEM) to transform this random excitation problem into a deterministic harmonic excitation one. The precise integration method (PIM) is extended to solve the equation of motion of beams under moving harmonic loads by enhancing the very recent consistent decomposition procedure, in order to simulate the movement of the loads. Six numerical examples are given to show the very high efficiency and accuracy of the method and also to deduce some useful preliminary conclusions from investigation of the dynamic statistical characteristics of a simply supported beam and of a symmetrical three span beam with its centre span unequal to the outer ones.

scholarly journals On the normal weston cadmium cell

1907 ◽  
Vol 80 (535) ◽  
pp. 75-76 ◽  
Keyword(s):  
Sulphuric Acid ◽  
Chemical Precipitation ◽  
Mean Value ◽  
Experimental Investigations ◽  
Guiding Principle ◽  
The Past ◽  
Primary Object ◽  
The Mean ◽  
Mercurous Nitrate ◽  
Set Up

The experimental investigations described had as their primary object the improvement of the Clark and cadmium cells as standards of electromotive force. In the past many investigators have pointed out that the mercurous sulphate used as a depolariser may produce variations in the E. M. F. as great as 0·002 volt, and the first thing sought by us was a mode of manufacture of the sulphate which could be relied on to give a constant product. We have prepared the salt in four ways: (1) Electrolytically (the method is due to Carhart and Hulett, and Wolff); (2) by chemical precipitation, mercurous nitrate being added to sulphuric acid; (3) by the recrystallisation of purchased samples of mercurous sulphate from strong sulphuric acid; and (4) by the action of fuming sulphuric acid on mercury. The mean value of the cells set up with the electrolytic salt is 1·01828 volts; with the sulphate prepared by (2) the E. M. F. is 1·01830 volts; (3) gives 1·01832 volts, and (4) gives 1·01831 volts. We conclude that the mode of manufacture of the depolariser is immaterial, provided that certain conditions are observed, and our guiding principle in the manufacture of the salt and the preparation of the paste is to prevent hydrolysis by keeping the salt in contact with dilute sulphuric acid (1 to 6) or with saturated cadmium sulphate solution.

Study on Ride Comfort of Non-Linear Vehicle Vibration System

2012 ◽  
Vol 215-216 ◽  
pp. 1043-1046
Author(s):  
Hai Yan Jing ◽  
Yan Ping Zheng ◽  
Ming Xia Fang
Keyword(s):  
Ride Comfort ◽  
Monotone Function ◽  
Random Excitation ◽  
Domain Model ◽  
Vehicle Body ◽  
Road Profile ◽  
Road Roughness ◽  
Non Linear ◽  
Rubber Bearings ◽  
The Mathematical Model

Based on the mathematical model of non-linear rubber bearings under the condition of random excitation and time domain model of road roughness, the 11-dof vibrant model for vehicle was built with considering the non-linear rubber bearings. Then the influence of the rubber bearings on ride comfort was simulated under the condition on the B-class road profile by different speed as the random input. The result shows that the way of modeling the vibrant model is feasible, and the influence is not a simple monotone function, especially in the barycenter acceleration of vehicle body.

scholarly journals Characteristics of cold-warm variation in the Hetao region and its surrounding areas in China during the past 5000 yr

2010 ◽  
Vol 6 (1) ◽  
pp. 1-18
Author(s):  
M. Li ◽  
Q. Ge ◽  
Z. Hao ◽  
J. Zheng ◽  
S. He
Keyword(s):  
Climate Changes ◽  
Mean Value ◽  
Data Series ◽  
Proxy Data ◽  
Average Temperature ◽  
The Past ◽  
The Mean ◽  
Temperature Proxy ◽  
Surrounding Areas

Abstract. Using six long-term temperature proxy data series derived from different natural evidences, including pollens and lake-sediments, we reconstructed a temperature series with a 100-year time resolution for the past 5000 yr in the Hetao region and its surrounding areas. The resulting series suggests that, on a millennial timescale, temperatures in the region were higher than the mean value of the whole series during the 5000~2600 yr before present (yr BP) period, and became relatively low comparing with the average temperature of the whole series after 2600 yr BP. Within these two periods, temperature fluctuations comprising numerous short, multi-centennial intervals also existed. A comparison between our reconstructed series and other series in China and across the Northern Hemisphere indicate that, on a long-term scale, cold–warm variations had been in phase across the whole hemisphere during the past 5000 yr; on the century to multi-century scale, the beginning and the ending times varied from region to region, thus implying that climate changes did not occur simultaneously in different regions.

scholarly journals Annotated Checklist of the Lichenicolous Fungi of Hungary

Diversity ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 557
Author(s):  
Nóra Varga ◽  
László Lőkös ◽  
Edit Farkas
Keyword(s):  
Field Studies ◽  
Mean Value ◽  
Lichenicolous Fungi ◽  
Distribution Maps ◽  
The Past ◽  
Key Characteristics ◽  
The Mean ◽  
Annotated Checklist ◽  
Detailed Work ◽  
Interesting Species

Knowledge of lichenicolous fungi is limited at a worldwide level and needs further basic information, as in the case of Central and Southern Europe. The literature sources for “Revised checklist of the Hungarian lichen-forming and lichenicolous fungi” by Lőkös and Farkas in 2009 contained 54 lichenicolous and other microfungi species of 38 genera. Due to recent field studies and microscopic work, the number of known species has increased to 104 lichenicolous species in 64 genera during the last decade, including 53 new species for the country. Old records of five species were confirmed by new collections. Key characteristics of some of the most interesting species are illustrated by microscopic views and two distribution maps are provided. Recent biodiversity estimates suggest that the number of currently known species could be 1.5 (–2) times higher with more detailed work on field collections. Although lichenicolous fungi have been less well studied in Hungary in the past, the relative diversity of lichenicolous fungi there, as indicated by Zhurbenko’s lichenicolous index, was found to be slightly higher than the mean value calculated for the world.

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