three dimensional model
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2022 ◽  
Vol 30 (7) ◽  
pp. 0-0

At present, most risk management work mainly relies on manpower, and manpower relies on the professional knowledge of relevant skilled workers to discover hidden safety risks in production activities. This article combines relevant big data theories and 4V characteristics to analyze and investigate safety production and big data, study data structure, data source and data type. Using 5W1H scientific big data and applications, this analysis method analyzes the theoretical basis, applications and beneficiaries of big data related to safety production, some of which are application links and important theoretical issues. Secondly, it studies the security risk management model based on big data, proposes a risk management model based on big data, the technical basis of big data and the idea of a three-dimensional model, and applies the systematic space method, which is reflected in three aspects of risk management. In the end, a risk identification model based on big data, a risk assessment classification model, and a risk early warning and pre-control model are defined.


2022 ◽  
Vol 9 (2) ◽  
pp. 41-54
Author(s):  
Altamimi et al. ◽  

This study aimed at bridging this gap and proposed a Three-Dimensional Model (Macro, Meso, and Micro). It also attempted to gain a deeper understanding of the nature of the glass ceiling, which limits women's participation in higher decision-making positions and determined how to overcome these barriers. The study adopted a mixed-methods approach. Three exploratory workshops involving 65 academic women leaders were conducted at three Saudi universities. This was followed by a field survey of the overall population involving 213 female leaders. Then six interviews of 35 female leaders were conducted. The results of the field survey illustrated the barriers preventing women from career development. According to the participants, the most challenging barriers at the institutional level were related to administrative and organizational aspects. They were followed by the barriers related to institutional culture. The social and personal barriers were ranked the last. The results of the interviews also revealed a set of ideas, which proposed methods to support women's progress to senior positions. They included political authority, policy development, open-door policy, adherence to the standards for selecting leaders based on competence, continuous evaluation, and professional development. The important role of the academic woman leader in the development of her career requires her to take responsibility for her professional growth and meet the requirements of the leadership role. The study recommends a comprehensive and profound treatment of the glass ceiling phenomenon. The study recommends a comprehensive training plan to support the skills, experiences, and capabilities of qualified women to occupy academic leadership. Benefiting from international expertise regarding this issue is highly recommended. There must be continuous monitoring and analysis of some quantitative and qualitative indicators based on an accurate database related to the academic empowerment of Saudi women.


2022 ◽  
Vol 9 (1) ◽  
Author(s):  
Yijie Zhang ◽  
Juhong Jia ◽  
Ziyi Guo

AbstractA personal microclimate management system is designed to maintain thermal comfort which allows people to overcome a harsh environment. It consists of several micro-fans placed in the garment side seam to provide cooling air. The computational fluid dynamics method was used to simulate the three-dimensional model and analysis the influence of fan’s number and air gap distance. The obtained results depict that the introduced cool airflow will find its way along paths with flow resistance minimized and exhaust through several separated exit. The body heat flux is taken away at the same time. The convection effect is enhanced by the increase in the fans’ numbers, but the fans’ cooling effect varies a lot because of various air gap distances. When the air gap is small enough, the cooling air impact the body surface directly and causes fierce heat loss. While the air gap distance is large enough, the heat transfer along the skin surface could be enhanced by the eddy flow which is existed in the air gap between body and garment. These phenomena can maintain the body’s thermal comfort in a suitable range.


Author(s):  
Manuel Friedrich ◽  
Lennart Machill

AbstractWe consider a two-dimensional model of viscoelastic von Kármán plates in the Kelvin’s-Voigt’s rheology derived from a three-dimensional model at a finite-strain setting in Friedrich and Kružík (Arch Ration Mech Anal 238: 489–540, 2020). As the width of the plate goes to zero, we perform a dimension-reduction from 2D to 1D and identify an effective one-dimensional model for a viscoelastic ribbon comprising stretching, bending, and twisting both in the elastic and the viscous stress. Our arguments rely on the abstract theory of gradient flows in metric spaces by Sandier and Serfaty (Commun Pure Appl Math 57:1627–1672, 2004) and complement the $$\Gamma $$ Γ -convergence analysis of elastic von Kármán ribbons in Freddi et al. (Meccanica 53:659–670, 2018). Besides convergence of the gradient flows, we also show convergence of associated time-discrete approximations, and we provide a corresponding commutativity result.


2022 ◽  
Vol 24 (1) ◽  
Author(s):  
Jeffrey S Lantis ◽  
Carmen Wunderlich

Abstract Constructivist theories of norm dynamics offer a variety of analytical tools to understand the complex processes of norm emergence, diffusion, and evolution over time. As the literature has developed, though, it lacks a general framing of the interconnections between norms, norm clusters or configurations, and principles or “normativity.” This article advances a new three-dimensional model of constructivist theories of norms that emphasizes the spatial dimensions of norm meanings, legitimacy, and impact and identifies promising avenues for research progress. First, individual norms represent a primary intersubjective structural component that is both developed and contested. Second, theories of norm interrelations or norm clusters provide additional critical dimensions of structuration that may promote resiliency in the face of contestation. Third, norms exist within a larger constellation of norm structures, representing the broadest dimension in world politics. Collisions can occur in this environment, but broader normativity and institutionalization often become activated in the face of serious challenges. As demonstrated using the illustration of international responses to the Syrian civil war (2011 till present), only by attending to all three dimensions of norms can we gain a more accurate understanding of real-world circumstances of norm connections, norm collisions, and the variable effects of norm contestation. The article concludes by identifying promising research avenues building from the three-dimensional framework.


2022 ◽  
Vol 2022 ◽  
pp. 1-10
Author(s):  
Habtamu Beri ◽  
Perumalla Janaki Ramulu

In this study, NACA0018 airfoil surface conformity test was conducted using API tracker3 in combination with SpatialAnalyzer (SA) and modeling software SolidWorks. Plaster of Paris is used as a plug making material and a woven-type fiberglass is used as mold and airfoil surface making material. For airfoil surface analysis, three-dimensional model of the airfoil surface was developed in SolidWorks software and imported in IGES file format to SpatialAnalyzer (SA) software. Then, measurements were taken from manufactured airfoil surface using laser tracker through surface scanning method. Surface conformity test was conducted through fitting of measured points to surface model imported from SolidWorks to SpatialAnalyzer (SA) software. The optimized fit summary result shows that the average fit difference is 0.0 having standard deviation from 0.22224 from the average and zero with RMS of 0.2210. The maximum magnitude of the difference including x and y together is 0.5336 and the minimum −0.5077. Thus, with a given range of surface quality specification, laser tracker is an easy and reliable measurement and inspection tool to be considered.


2022 ◽  
Author(s):  
Saeed Darki ◽  
Evgeniy Yurevich Raskatov

Abstract In this study, considering all the parameters in radial forging and a three-dimensional model has been simulated using the finite element method. By implementing an elastoplastic state for the specimen tube, parameters such as friction type, residual stress distribution, effective strain distribution, material flow velocity and its effect on the neutral plate and the distribution of force in the die have been studied and analyzed. The effects of angle on the quality and characteristics of the specimen and the longevity of the die have also been obtained. Experimental results have been used to confirm the accuracy of the simulation. The results of the hardness test after forging were compared with the simulation results. Good agreement between the results indicates the accuracy of the simulation in terms of hardness. Therefore, this validation allows confirming the other obtained results for the analysis and prediction of various components in the forging process. After the validation and confirmation of the results through the hardness test, the hardness distribution was obtained by considering temperature changes and the effective strain on the specimen.


2022 ◽  
pp. 60-69
Author(s):  
SVITLANA BOBROVA ◽  
TETIANA YELINA ◽  
LIUDMYLA HALAVSKA ◽  
VOLODYMYR SHCHERBAN ◽  
OKSANA KOLISKO

Purpose. The purpose of this study is to develop a mathematical description of the transformation of the frame model of weft-knits under the action of tensile forces in the courswise direction for further three-dimensional modeling of the knited structure.Methodology. Methods of theoretical analysis and synthesis, basics of knitting theory, methods of geometric modeling and parameterization were used in the research process.Findings. Considering the knitwear stretching during the use of the clothing is one of the determining factors of the quality of design decisions. When stretching the weft-knitted fabrics in the coursewise direction, the configuration of its individual stitches’ changes, as well as the thread’s cross-section due to the force interaction between the adjacent structure elements. To simulate the physical and mechanical behavior of knitwear under the stretching, it is suggested using a complex model of knitwear deformation, that includes the suggested frame model of uniaxial coursewise stretching of knitted fabrics. An algorithm for constructing a frame model of stretching a sample of knitted fabric in the coursewise direction is described in the paper. The algorithm is based on the structure parameters, including the wale spacing and course spacing in a dry relaxed state, the relative elongation of the sample at the time of modeling, number of wales and courses in the sample, the coefficient of courses narrowing. Scientific novelty. The paper investigates the features of the transformation of the knitting structure during stretching in the coursewise direction and offers algorithmic and mathematical support for the automated generation of the mesh frame in the context of three-dimensional modeling, which provides for the possibility of considering the dynamics of deformation of knitted fabric undergoing tensile deformations.Practical value. Frame model of the weft-knits deformation and algorithm of mesh-frame construction suggested in the paper, form the basis for determination of coordinates of characteristic points of the structural elements of the knit in a state of uniaxial tension for construction of a three-dimensional model of thread a deformed knitted fabric.


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