Structure Design Based on Mechanism and Materials Property

2014 ◽  
Vol 620 ◽  
pp. 100-103
Author(s):  
Heng Li Liu ◽  
Bao Shun Liu ◽  
Xiao Na Li

For products, the structure determines function; appearance form aesthetic; and the two co-exist to achieve the perfect unity of function and aesthetics, but in fact, the structure is largely affects the product shape. In this paper, classified the product structure according to function, analyzed the impact of the typical structural design to the shape of product, and also pointed out that the development of science and technology and material choice are also an important factor in the structure design, thereby affected the design of the product styling. By analyzing, it elaborated fully the impact of structural design and its importance in the product design, and provided one practical way of thinking.

Author(s):  
D. Zhang

Structural fatigue plays a very important role in plating structural design. There are a lot of efforts in finding effective ways to improve the fatigue life of the plating structure. One of the means is to use welding profile. Welding profile is widely used in fatigue sensitive areas to improve the fatigue life of offshore platforms. How to evaluate the impact of welding profile to fatigue life calculation has always been the topic of engineering design. This paper will study the impact of different shapes of welding profiles to the fatigue life of structure through a real project example, and discuss its application in platform design. Different welding profiles have large impact on fatigue life; and an achievable good welding profile can improve the fatigue life dramatically. With the help of welding profiles, offshore engineers can achieve a more efficient design of the structure.


2018 ◽  
Vol 176 ◽  
pp. 02014
Author(s):  
Chun Li ◽  
Kaining Meng ◽  
Qinqin Yu

Serious pollution problems in the global offshore area are caused by a large number of municipal wastes from land. The reason is that there are many unenvironmental structure designs in the product design, which brings a lot of waste of resources and environmental pollution and other problems. Based on the principle of 3R, this article integrates the thought of ecological structure design into the "human-machine-environment" ecosystems; establishes the ideological system of product ecological structure design; confirms the feasibility of product ecological structure design with analysis of relevant design cases. Then to establish the assessment system of the economical system to evaluate the ecology of the product structure design.


Author(s):  
Ke-Zheng Huang ◽  
Huai-Wei Ren

Tolerancing is an essential part of a product design process. It is traditionally performed after the product structure has been determined. The product precision requirements may not be fully utilized for the decision making for selecting the best structure in the early stage of product design — the conceptual design phase. A growth design method has been proposed for product structure design and concurrent tolerancing, in which the product form and tolerance can be generated in the same way as an organism grows. The basic feature of biology, cell division, has been borrowed as the design guiding principle. Product conceptual model has been built as the basis of form and tolerance growth design. The relationship of product function, structure and tolerance was analysed to explain on what and how they act in product design process. Tolerance mathematic model expressed by screw parameters and expression model based on Technologically and Topologically Related Surface (TTRS) are described to execute the tolerance allocation. The automation selection of Datum reference frame (DRF) can facilitate the generation of tolerance. Finally, a prototype form design and tolerancing system has been implemented and applied to a dedicated fixture design to verify the validity of the growth design.


2020 ◽  
Vol 15 (1) ◽  
pp. 37-44
Author(s):  
El Mehdi Echebba ◽  
Hasnae Boubel ◽  
Oumnia Elmrabet ◽  
Mohamed Rougui

Abstract In this paper, an evaluation was tried for the impact of structural design on structural response. Several situations are foreseen as the possibilities of changing the distribution of the structural elements (sails, columns, etc.), the width of the structure and the number of floors indicates the adapted type of bracing for a given structure by referring only to its Geometric dimensions. This was done by studying the effect of the technical design of the building on the natural frequency of the structure with the study of the influence of the distribution of the structural elements on the seismic response of the building, taking into account of the requirements of the Moroccan earthquake regulations 2000/2011 and using the ANSYS APDL and Robot Structural Analysis software.


2021 ◽  
Vol 11 (9) ◽  
pp. 4071
Author(s):  
Yali Zhang ◽  
Xinrong Huang ◽  
Yubin Lan ◽  
Linlin Wang ◽  
Xiaoyang Lu ◽  
...  

Aerial electrostatic spray technology for agriculture is the integration of precision agricultural aviation and electrostatic spray technology. It is one of the research topics that have been paid close attention to by scholars in the field of agricultural aviation. This study summarizes the development of airborne electrostatic spray technology for agricultural use in China, including the early research and exploration of Chinese institutions and researchers in the aspects of nozzle structure design optimization and theoretical simulation. The research progress of UAV-based aerial electrostatic spray technology for agricultural use in China was expounded from the aspects of nozzle modification, technical feasibility study, influencing mechanism of various factors, and field efficiency tests. According to the current development of agricultural UAVs and the characteristics of the farmland environment in China, the UAV-based aerial electrostatic spray technology, which carries the airborne electrostatic spray system on the plant protection UAVs, has a wide potential in the future. At present, the application of UAV-based aerial electrostatic spray technology has yet to be further improved due to several factors, such as the optimization of the test technology for charged droplets, the impact of UAV rotor wind field, comparison study on charging modes, and the lack of technical accumulation in the research of aerial electrostatic spray technology. With the continuous improvement of the research system of agricultural aviation electrostatic spray technology, UAV-based electrostatic spray technology will give play to the advantages in increasing the droplets deposition on the target and reducing environmental pollution from the application of pesticides. This study is capable of providing a reference for the development of the UAV-based agricultural electrostatic spray technology and the spray equipment.


Author(s):  
Jialin Tian ◽  
Xuehua Hu ◽  
Liming Dai ◽  
Lin Yang ◽  
Yi Yang ◽  
...  

This paper presents a new drilling tool with multidirectional and controllable vibrations for enhancing the drilling rate of penetration and reducing the wellbore friction in complex well structure. Based on the structure design, the working mechanism is analyzed in downhole conditions. Then, combined with the impact theory and the drilling process, the theoretical models including the various impact forces are established. Also, to study the downhole performance, the bottom hole assembly dynamics characteristics in new condition are discussed. Moreover, to study the influence of key parameters on the impact force, the parabolic effect of the tool and the rebound of the drill string were considered, and the kinematics and mechanical properties of the new tool under working conditions were calculated. For the importance of the roller as a vibration generator, the displacement trajectory of the roller under different rotating speed and weight on bit was compared and analyzed. The reliable and accuracy of the theoretical model were verified by comparing the calculation results and experimental test results. The results show that the new design can produce a continuous and stable periodic impact. By adjusting the design parameter matching to the working condition, the bottom hole assembly with the new tool can improve the rate of penetration and reduce the wellbore friction or drilling stick-slip with benign vibration. The analysis model can also be used for a similar method or design just by changing the relative parameters. The research and results can provide references for enhancing drilling efficiency and safe production.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
Q Zhao ◽  
H Xu ◽  
J Lv ◽  
Y Wu

Abstract Background The prevalence of aortic stenosis (AS) steadily increases with age. There is a consensus that intervention should be advised in patients with symptomatic severe AS. However, decision to operate raises complex issues in the elderly due to the increasing operative comorbidity and mortality. There is limited information regarding the characteristics and outcome of elderly patients with symptomatic severe AS who were denied intervention and the reasons leading to the denial. Purpose To analyze the decision-making and the prognosis in elderly patients with symptomatic severe AS. Methods In a cohort of 8929 patients aged ≥60 years with significant valvular heart disease, we divided patients with severe (valve area ≤1 cm2 or peak velocity ≥4.0 m/s or mean gradient ≥40 mmHg), symptomatic (angina or NYHA II-IV or syncope) AS into three groups by final treatment decision: intervention group, doctor-deny group, patient-deny group. The impact of characteristics on decision-making was evaluated and 1-year mortality among three groups were compared. Results Among 546 patients with severe symptomatic AS, the interventional decision was taken in 338 patients (61.9%), 134 patients (24.5%) were denied intervention by doctor after evaluation and 74 patients (13.5%) refused intervention due to personal preference. In multivariable analysis, age [OR=1.104, 95% CI (1.068–1.142)], multi-comorbidities [OR=4.706, 95% CI (2.355–9.403)] and left ventricular end-diastolic diameter (LVEDD) [OR=1.021, 95% CI (1.001–1.042)] were markedly associated with the conservative decision made by doctor, while LVEF >50% [OR=0.260, 95% CI (0.082–0.823)] was significantly linked with the interventional decision. Lower mortality was observed in intervention group during 1-year follow-up compared with either doctor-deny group or patient-deny group (both P<0.001 after adjustment). Further, diabetes [HR=2.513, 95% CI (1.243–5.084)], syncope [HR=2.856, 95% CI (1.338–6.098)], atrial fibrillation (AF) [HR=2.764, 95% CI (1.305–5.855)], stroke [HR=2.921, 95% CI (1.252–6.851)] and multi-comorbidities [HR=3.120, 95% CI (1.363–7.142)] were strong 1-year mortality predictors, whereas interventional treatment [HR=0.195, 95% CI (0.091–0.417)] and LEVF >50% [HR=0.960, 95% CI (0.938–0.984)] were related to lower mortality. Conclusions Intervention was denied in about forty percent of elderly patients with symptomatic severe AS. Patients with advanced age, multi-comorbidities and increased LVEDD tended to be denied intervention by doctors, whereas interventions were more likely to be performed on patients with normal LVEF. Diabetes, syncope, AF, stroke and multi-comorbidities were the predictive factors of 1-year mortality. Elderly patients with symptomatic severe AS could benefit from intervention. Patient education needs to be strengthened, to encourage more patients accept the appropriate intervention. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Twelfth Five-year Science and Technology Support Projects by Ministry of Science and Technology of China


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