scholarly journals Dynamic Simulation Analysis and Experiment of Large-caliber Self-propelled Pipeline Crawler Based on ADAMS

2021 ◽  
Vol 2095 (1) ◽  
pp. 012049
Author(s):  
Yinlong Tang ◽  
Huadong Song ◽  
Yating Yu ◽  
Jun Zhang ◽  
Wenguang Hu ◽  
...  
Keyword(s):  
Simulation Analysis ◽  
Solution Process ◽  
Analysis Method ◽  
Long Period ◽  
The Past ◽  
Output Torque ◽  
Driving Wheel ◽  
Motion Performance ◽  
Solid Works ◽  
Torque Values

Abstract The force states of driving wheels are different when the self-propelled pipeline crawler moves in the pipeline, so it is difficult to carry out accurate theoretical analysis and calculation on the force and output torque values of each driving wheel in horizontal, climbing and turning conditions of the crawler. Due to the complex mechanical properties of pipeline sealing and the limitation of visualization, it takes a long period and high cost to develop the robot in pipeline by experimental means. With the gradual application of virtual simulation means, the complicated dynamic analysis and solution process in the past has become relatively easy. In this paper, Solid works is used to establish a simplified model of the crawler, and ADAMS is used to analyze and simulate the dynamics of the crawler. The force of the multi-wheel driven pipeline crawler is given under the condition of horizontal, climbing 35° and turning, which provides the necessary analysis method and theoretical basis for the design optimization and improvement. Finally, the horizontal, climbing and bending motion performance of the crawler is verified by comprehensive pipeline experiment.

Application of Coupled Structural Acoustic Analysis and Sensitivity Calculations to a Tire Noise Problem

2012 ◽  
Vol 40 (1) ◽  
pp. 25-41 ◽  
Author(s):  
H. M. R. Aboutorabi ◽  
L. Kung
Keyword(s):  
Performance Improvement ◽  
Acoustic Analysis ◽  
Simulation Analysis ◽  
Analysis Method ◽  
Vehicle Manufacturer ◽  
Element Analysis ◽  
Equipment Manufacturer ◽  
Tire Noise ◽  
Fea Modeling ◽  
Testing Instruments

Abstract REFERENCE: H. M. R. Aboutorabi and L. Kung, “Application of Coupled Structural Acoustic Analysis and Sensitivity Calculations to a Tire Noise Problem,” Tire Science and Technology, TSTCA, Vol. 40, No. 1, January – March 2012, pp. 25–41. ABSTRACT: Tire qualification for an original equipment (OE) program consists of several rounds of submissions by the tire manufacturer for evaluation by the vehicle manufacturer. Tires are evaluated both subjectively, where the tire performance is rated by an expert driver, and objectively, where sensors and testing instruments are used to measure the tire performance. At the end of each round of testing the evaluation results are shared and requirements for performance improvement for the next round are communicated with the tire manufacturer. As building and testing is both expensive and time consuming predictive modeling and simulation analysis that can be applied to the performance of the tire is of great interest and value. This paper presents an application of finite element analysis (FEA) modeling along with experimental verification to solve tire noise objections at certain frequencies raised by an original equipment manufacturer (OEM) account. Coupled structural-acoustic analysis method was used to find modal characteristics of the tire at the objectionable frequencies. Sensitivity calculations were then carried out to evaluate the strength of contribution from each tire component to the identified modes. Based on these findings changes to the construction were proposed and implemented that addressed the noise issue.

scholarly journals A DESIGN RATIONALE ANALYSIS METHOD TOWARDS ROBUST ARTIFACT DESIGN

2021 ◽  
Vol 1 ◽  
pp. 71-80
Author(s):  
Yusuke Tsutsui ◽  
Yuya Mitake ◽  
Mar'atus Sholihah ◽  
Shigeru Hosono ◽  
Yoshiki Shimomura
Keyword(s):  
Robust Design ◽  
Design Rationale ◽  
Analysis Method ◽  
The Past ◽  
Previous Design ◽  
Artifact Design

AbstractTo design a more robust artifact, an artifact design based on a design rationale analysis is pivotal. Errors in previous design rationales that led to the degradation of artifact robustness in the past provide valuable knowledge towards improving the robust design. However, methods for exposing and analysing errors in design rationale remain unclear. This paper proposes a structured method for a design rationale analysis based on logical structuring. This method provides a well-constructed means of identifying and analysing errors in design rationale from the perspective of knowledge operation.

scholarly journals Evolution of the hypsometric relationship in Araucaria angustifolia plantations in the mid-south region of Paraná state

CERNE ◽  
2010 ◽  
Vol 16 (3) ◽  
pp. 347-357 ◽  
Author(s):  
Afonso Figueiredo Filho ◽  
Andrea Nogueira Dias ◽  
Sintia Valerio Kohler ◽  
Aline Angélica Verussa ◽  
Ademar Luiz Chiquetto
Keyword(s):  
Coefficient Of Determination ◽  
Generic Model ◽  
Araucaria Angustifolia ◽  
Analysis Method ◽  
Total Height ◽  
The Past ◽  
Satisfactory Performance ◽  
Standard Estimate ◽  
Estimate Error ◽  
The Right

The aim of this study was to assess and model the evolution of the hypsometric relationship in Araucaria angustifolia plantations grown in the 1940's and 1960's in the Irati National Forest, in the mid-south region of Paraná state, Brazil. Using the complete stem analysis method, it was possible to reconstitute the past annual growth of the diameter at 1.3 m (d) and of the total height (h) of a sample of 30 trees, selected so as to cover diametric and age variability. Eleven discs were removed from each tree at 0.1 and 1.3 m and at 15, 25, 35,..., 95% of the total height. Eleven models traditionally used in hypsometric relationships were tested, two of which were considered generic because they involved the age variable. The models were selected based on the Adjusted Coefficient of Determination (R²Adj), Standard Estimate Error (Syx), absolute (m) and relative (%), and on the graphic distribution of residues in percentage. In the models tested by age, no tendencies were observed and erros (Syx) remained below 14.6%, except for ages 5 and 11. However, the coefficients of determination were low, ranging from 0.29 to 0.55. The Curtis generic model (1970), selected to represent the h/d curve for all ages, also presented a satisfactory performance (R²Adj = 0.87 and Syx = 16%), with results similar to those obtained for the models in each age. As age increases, the h/d curve shifts to the right and changes level, remaining steep at the younger ages and more stable and flat as the population nears the end of its cycle.

scholarly journals Changes in the strength and width of the Hadley Circulation since 1871

2012 ◽  
Vol 8 (4) ◽  
pp. 1169-1175 ◽  
Author(s):  
J. Liu ◽  
M. Song ◽  
Y. Hu ◽  
X. Ren
Keyword(s):  
20Th Century ◽  
Global Climate ◽  
Hadley Circulation ◽  
Recent Change ◽  
Early 20Th Century ◽  
Greenhouse Warming ◽  
Long Period ◽  
The Past ◽  
Period Oscillation

Abstract. Recent studies demonstrate that the Hadley Circulation has intensified and expanded for the past three decades, which has important implications for subtropical societies and may lead to profound changes in global climate. However, the robustness of this intensification and expansion that should be considered when interpreting long-term changes of the Hadley Circulation is still a matter of debate. It also remains largely unknown how the Hadley Circulation has evolved over longer periods. Here, we present long-term variability of the Hadley Circulation using the 20th Century Reanalysis. It shows a slight strengthening and widening of the Hadley Circulation since the late 1970s, which is not inconsistent with recent assessments. However, over centennial timescales (1871–2008), the Hadley Circulation shows a tendency towards a more intense and narrower state. More importantly, the width of the Hadley Circulation might have not yet completed a life-cycle since 1871. The strength and width of the Hadley Circulation during the late 19th to early 20th century show strong natural variability, exceeding variability that coincides with global warming in recent decades. These findings raise the question of whether the recent change in the Hadley Circulation is primarily attributed to greenhouse warming or to a long-period oscillation of the Hadley Circulation – substantially longer than that observed in previous studies.

scholarly journals Effect of fungus Heterobasidion Annosum (FR) bref. on fir and spruce dying in the region of the NP "Durmitor" and "Biogradska gora"

2002 ◽  
pp. 49-58 ◽  
Author(s):  
Milosav Andjelic
Keyword(s):  
Infection Intensity ◽  
Heterobasidion Annosum ◽  
Parasitic Fungus ◽  
Anthropogenic Factors ◽  
Abiotic Factor ◽  
Forest Reserve ◽  
Virgin Forest ◽  
Long Period ◽  
The Past ◽  
The Impact

Several adverse factors of abiotic and biotic nature affect the vitality and decline of spruce and fir in the region of NP "Durmitor" and NP "Biogradska Gora". The most significant adverse abiotic factor is air pollution. Among the adverse biotic factors, the most significant is by all means the parasitic fungus Heterobasidion annosum. The damage caused by this fungus is especially severe in spruce and fir stands in the region of the NP "Durmitor". The infection intensity is approximately the same in both species. The damage caused by H. annosum is greater in the forests of NP "Durmitor", than in the forests of NP "Biogradska Gora". This can be explained by the fact that spruce and fir stands on Durmitor were felled without maintaining the forest order. In the virgin forest reserve NP "Biogradska Gora" in the past there were no fellings, i.e. the impact of anthropogenic factors was excluded. Fungus H. annosum cannot be eliminated form spruce and fir stands on Durmitor, but the treatment of stumps (immediately after the sanitation felling) with "Penofil" or "Borax" can check the velocity of its spread. In this way, the forest is given an opportunity to form more resistant populations through a long period by natural selection .

scholarly journals Need to Change Exam Preparation Strategy

2017 ◽  
Vol 4 (2) ◽  
Author(s):  
Akhil Subhash Madankar
Keyword(s):  
Learning Process ◽  
Educational Tool ◽  
Long Period ◽  
The Past ◽  
Exam Preparation ◽  
The World ◽  
Examination Methods ◽  
Preparation Strategy ◽  
Expected Outcomes ◽  
The Way

All over the world, there are different students who acquired the different ways of preparation.  Every professional graduator having different mindsets or approach towards the examination. Due to this, some student will get good outcomes in minimum time and some will not get expected outcomes even when they were tried a lot. The examination methods have a large impact on how and when student study and what they learn. The examination should not only be used as a control that a student is qualified, but also as an educational tool to influence the learning process. Over a long period of time, students were thinking that exam would the way where we will express our knowledge. But according to some student will be not. Now a day, a number of students adopted different way of learning and attempting the examination. And getting good marks in an exam will not be an issue. Today, the world is practical oriented. They demand not only the base of knowledge but a group of knowledge along with skills. Also, the way of learning is different than the past decade. Now we have to change our mindset regarding exam and way which will be adopting for it.

scholarly journals APPLICABILITY OF THE VERTICAL TELESCOPIC BREAKWATER USING THE PAST TYPHOON IN TOKYO BAY

2020 ◽  
pp. 35
Author(s):  
Yako Harada ◽  
Yukihisa Matsumoto ◽  
Kazuho Morishita ◽  
Nobuyuki Oonishi ◽  
Kazuyoshi Kihara ◽  
...  
Keyword(s):  
Climate Change ◽  
Storm Surge ◽  
Storm Surges ◽  
Numerical Calculations ◽  
Numerical Analyses ◽  
Tokyo Bay ◽  
Worst Case ◽  
Sea Levels ◽  
Long Period ◽  
The Past

The vertical telescopic breakwater(VTB), which is a new breakwater that permits the navigation of ships, remain at the bottom of the sea during calm and rise to the surface during tsunamis or storm surges. Kawai et al. (2017) and Arikawa et al. (2019) found that it is effective not only for swell waves, but also for long-period waves simulating tsunamis and storm surges by previous experiments and numerical analyses. However, there have been few studies on the performance of VTB by numerical calculations in actual ports using actual typhoons. In addition, sea levels and changes in characteristics of typhoon due to climate change are predicted to occur; hence, we are concerned about the damage in all quarters caused by storm surge inundation, especially at Tokyo. Therefore, in this study, we used hypothetical typhoons under worst-case scenarios and quantitatively evaluated the protection performance of VTB against hypothetical typhoons with different aperture rates of VTB in Tokyo Bay by the numerical simulation.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/qof5ixKqIiA

Using the Explicit Dynamic Method to Simulate Pile Dynamical Driving Process

2010 ◽  
Vol 163-167 ◽  
pp. 366-371
Author(s):  
Jian Bing Lv ◽  
He Lin Fu ◽  
Hua Zhi Li ◽  
Zhe Liu
Keyword(s):  
Method Development ◽  
Elastic Solid ◽  
Computational Method ◽  
Dynamical Analysis ◽  
Pile Driving ◽  
Past Study ◽  
Analysis Method ◽  
The Past ◽  
Explicit Dynamic ◽  
Dynamical Stress

The dynamic pile driving process is so complex that till now the analysis on the process had been focusing on the filed test or laboratory test. However, the past study about the dynamic process is a time consuming one; with the computational method development, the numerical simulation on this process is possible. In this paper, explicit dynamical analysis method is adopted, the pile is simulated using the elastic solid element, two computational cases are considered and finally the pile driving process dynamical stress is studied.

scholarly journals A spatial and temporal analysis on NDVI in Urad grassland during 2010-2019 over remote sensing

2021 ◽  
Vol 336 ◽  
pp. 06029
Author(s):  
Yueying Zhang ◽  
Tiantian Liu ◽  
Yuxi Wang ◽  
Ming Zhang ◽  
Yu Zheng
Keyword(s):  
Remote Sensing ◽  
Trend Analysis ◽  
Temporal Analysis ◽  
Vegetation Coverage ◽  
Analysis Method ◽  
Modis Ndvi ◽  
The Past ◽  
Spatial And Temporal Analysis ◽  
Change Trend ◽  
Temporal And Spatial

The temporal-spatial dynamic variation of vegetation coverage from 2010 to 2019 in Urad Grassland, Inner Mongolia has been investigated by analysing on MODIS NDVI remote sensing products. This paper applies pixel dichotomy approach and linear regression trend analysis method to analyze the temporal and spatial evolution trend of vegetation coverage over the past 10 years. The average annual vegetation coverage showed a downward trend in general from 2010 to 2019. The vegetation distribution and change trend analysis provide a thorough and scientific reference for policymaking in environmental protection.

The Symbolism of Colors in Art – Traditions and Modernity

2021 ◽  
Vol 5 (1) ◽  
Author(s):  
Maya Dimcheva ◽  
Keyword(s):  
Geographical Location ◽  
Symbolic Meaning ◽  
Human Consciousness ◽  
Cultural Traditions ◽  
Modern Times ◽  
Long Period ◽  
The Past ◽  
Ancient Times

The colors in art have always influenced the human consciousness through the power of the symbolism embedded in them from ancient times to the present. Some color values from the past are preserved for a long period of time, while others are transformed with a certain meaning in time, depending on various factors such as religion, cultural traditions, geographical location, etc. In modern times, the symbolic meaning of color is rethought with a new content, often uniting those laws that were once the basis of ancient knowledge.

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