Simulation of drawing process based on fiber arrangement in the sliver with straightness and separation degree

2021 ◽  
pp. 004051752110342
Author(s):  
Na Sun
Keyword(s):  
High Velocity ◽  
Prediction Accuracy ◽  
Drawing Process ◽  
Low Velocity ◽  
Model Based ◽  
Fiber Arrangement ◽  
Separation Degree ◽  
Relative Errors

Sliver irregularity, straightness and separation degree of fibers are three crucial factors in sliver quality. Considering the straightness and separation degree, the drafting model based on the fiber arrangement in the sliver was applied to simulate the drawing process. First, the fiber arrangement in the carding sliver was developed. Then, the drafting process was divided into the low-velocity stage, straightening stage and high-velocity stage to carry out the redistribution of the fiber arrangement so that the sliver quality after drafting can be recalculated from the new fiber arrangement after the drafting procedure. Combining the doubling procedure, the simulated sliver quality of each drawing process was demonstrated to be close to the actual values, taking the straightness and separation degree into consideration. The relative errors between the simulated straightness and percentage of separated fibers and the tested one were all less than 10%. The prediction accuracy of sliver irregularity was raised by about 40%. In addition, the simulated results strongly confirmed the theory that the drawing process has an influence on straightening the hooked fibers, separating the fiber in the assembly and improving the sliver evenness, which cannot be reflected in previous models.

scholarly journals Effect of Tool Geometry Parameters on the Formability of a Camera Cover in the Deep Drawing Process

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3993
Author(s):  
Thanh Trung Do ◽  
Pham Son Minh ◽  
Nhan Le
Keyword(s):  
Deep Drawing ◽  
Thickness Distribution ◽  
Metal Flow ◽  
Sheet Thickness ◽  
Side Wall ◽  
Tool Geometry ◽  
Drawing Process ◽  
Nose Radius ◽  
Deep Drawing Process

The formability of the drawn part in the deep drawing process depends not only on the material properties, but also on the equipment used, metal flow control and tool parameters. The most common defects can be the thickening, stretching and splitting. However, the optimization of tools including the die and punch parameters leads to a reduction of the defects and improves the quality of the products. In this paper, the formability of the camera cover by aluminum alloy A1050 in the deep drawing process was examined relating to the tool geometry parameters based on numerical and experimental analyses. The results showed that the thickness was the smallest and the stress was the highest at one of the bottom corners where the biaxial stretching was the predominant mode of deformation. The problems of the thickening at the flange area, the stretching at the side wall and the splitting at the bottom corners could be prevented when the tool parameters were optimized that related to the thickness and stress. It was clear that the optimal thickness distribution of the camera cover was obtained by the design of tools with the best values—with the die edge radius 10 times, the pocket radius on the bottom of the die 5 times, and the punch nose radius 2.5 times the sheet thickness. Additionally, the quality of the camera cover was improved with a maximum thinning of 25% experimentally, and it was within the suggested maximum allowable thickness reduction of 45% for various industrial applications after optimizing the tool geometry parameters in the deep drawing process.

An interpretable mechanism for personalized recommendation based on cross feature

2021 ◽  
pp. 1-12
Author(s):  
Lv YE ◽  
Yue Yang ◽  
Jian-Xu Zeng
Keyword(s):  
Recommender System ◽  
Online Shopping ◽  
Side Information ◽  
Attention Mechanism ◽  
Personalized Recommendation ◽  
Model Based ◽  
Embedded Model ◽  
Feature Attention ◽  
Match Score

The existing recommender system provides personalized recommendation service for users in online shopping, entertainment, and other activities. In order to improve the probability of users accepting the system’s recommendation service, compared with the traditional recommender system, the interpretable recommender system will give the recommendation reasons and results at the same time. In this paper, an interpretable recommendation model based on XGBoost tree is proposed to obtain comprehensible and effective cross features from side information. The results are input into the embedded model based on attention mechanism to capture the invisible interaction among user IDs, item IDs and cross features. The captured interactions are used to predict the match score between the user and the recommended item. Cross-feature attention score is used to generate different recommendation reasons for different user-items.Experimental results show that the proposed algorithm can guarantee the quality of recommendation. The transparency and readability of the recommendation process has been improved by providing reference reasons. This method can help users better understand the recommendation behavior of the system and has certain enlightenment to help the recommender system become more personalized and intelligent.

Detection of effort maximality in adults performing isokinetic wrist flexion and extension

2021 ◽  
pp. 1-7
Author(s):  
Mercè Torra ◽  
Eduard Pujol ◽  
Anna Maiques ◽  
Salvador Quintana ◽  
Roser Garreta ◽  
...  
Keyword(s):  
High Velocity ◽  
Healthy Male ◽  
Wrist Flexion ◽  
Low Velocity ◽  
Wrist Extensor ◽  
Submaximal Effort ◽  
The Difference ◽  
Muscle Groups ◽  
Maximal Effort ◽  
Flexion And Extension

BACKGROUND: The difference between isokinetic eccentric to concentric strength ratios at high and low velocities (DEC) is a powerful tool for identifying submaximal effort in other muscle groups but its efficiency in terms of the wrist extensors (WE) and flexors (WF) isokinetic effort has hitherto not been studied. OBJECTIVE: The objective of the present study is to examine the usefulness of the DEC for identifying suboptimal wrist extensor and flexor isokinetic efforts. METHODS: Twenty healthy male volunteers aged 20–40 years (28.5 ± 3.2) were recruited. Participants were instructed to exert maximal and feigned efforts, using a range of motion of 20∘ in concentric (C) and eccentric (E) WE and WF modes at two velocities: 10 and 40∘/s. E/C ratios (E/CR) where then calculated and finally DEC by subtracting low velocity E/CR from high velocity ones. RESULTS: Feigned maximal effort DEC values were significantly higher than their maximal effort counterparts, both for WF and WE. For both actions, a DEC cutoff level to detect submaximal effort could be defined. The sensitivity of the DEC was 71.43% and 62.5% for WE ad WF respectively. The specificity was 100% in both cases. CONCLUSION: The DEC may be a valuable parameter for detecting feigned maximal WF and WE isokinetic effort in healthy adults.

scholarly journals Studying the Depth Structure of the Kyrgyz Tien Shan by Using the Seismic Tomography and Magnetotelluric Sounding Methods

Geosciences ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 122
Author(s):  
Irina Medved ◽  
Elena Bataleva ◽  
Michael Buslov
Keyword(s):  
Seismic Tomography ◽  
High Velocity ◽  
Fault Zones ◽  
Magnetotelluric Sounding ◽  
Tien Shan ◽  
High Resistivity ◽  
Low Velocity ◽  
Low Resistivity ◽  
Velocity Models ◽  
Fluid Saturation

This paper presents new results of detailed seismic tomography (ST) on the deep structure beneath the Middle Tien Shan to a depth of 60 km. For a better understanding of the detected heterogeneities, the obtained velocity models were compared with the results of magnetotelluric sounding (MTS) along the Kekemeren and Naryn profiles, running parallel to the 74 and 76 meridians, respectively. We found that in the study region the velocity characteristics and geoelectric properties correlate with each other. The high-velocity high-resistivity anomalies correspond to the parts of the Tarim and Kazakhstan-Junggar plates submerged under the Tien Shan. We revealed that the structure of the Middle Tien Shan crust is conditioned by the presence of the Central Tien Shan microcontinent. It manifests itself as two anomalies lying one below the other: the lower low-velocity low-resistivity anomaly, and the upper high-velocity high-resistivity anomaly. The fault zones, limiting the Central Tien Shan microcontinent, appear as low-velocity low-resistivity anomalies. The obtained features indicate the fluid saturation of the fault zones. According to the revealed features of the Central Tien Shan geological structure, it is assumed that the lower-crustal low-velocity layer can play a significant role in the delamination of the mantle part of the submerged plates.

Separation Standards—II

1966 ◽  
Vol 19 (2) ◽  
pp. 169-186 ◽  
Author(s):  
P. G. Reich
Keyword(s):  
One Dimension ◽  
Collision Risk ◽  
Practical Applications ◽  
Upper Limit ◽  
Intensive Observation ◽  
Relative Errors ◽  
Separation Standards

In the first part of this series of papers an outline was given of the approach made at the Royal Aircraft Establishment to the problems of estimating collision risk and of specifying the quality of navigation needed to make separation standards safe. It was stressed that estimates should be based on intensive observation of flying errors, rather than on speculative theories, and that it is more feasible to develop ‘upper limit’ estimating techniques than those which purport to give the exact risk. In summary, a list of seven ‘requirements’ was given, as a reminder of the essential principles which can so easily be overlooked in the piecemeal task of relating separation standards to collision risk.The purpose of this paper is to show some of the theoretical techniques which have been developed at R.A.E. to satisfy five of these requirements. (The remaining two do not call for special techniques and will be dealt with when practical applications are described in Part III.) The paper contains three Appendixes, dealing with the frequency of losing separation in one dimension, the computation of P's from the assumed tail shapes, and the treatment of relative errors. These are not included here but will appear in the off-printed version which may be obtained from the Royal Aircraft Establishment.Both this paper and the paper that follows by Mr. Attwooll are crown copyright and are reproduced with the permission of H.M. Stationery Office.

scholarly journals A MODEL BASED ON FUZZY LINGUISTIC INFORMATION TO EVALUATE THE QUALITY OF DIGITAL LIBRARIES

2010 ◽  
Vol 09 (03) ◽  
pp. 455-472 ◽  
Author(s):  
F. J. CABRERIZO ◽  
J. LÓPEZ-GIJÓN ◽  
A. A. RUÍZ ◽  
E. HERRERA-VIEDMA
Keyword(s):  
Digital Libraries ◽  
User Satisfaction ◽  
Information Access ◽  
Great Influence ◽  
Linguistic Information ◽  
Model Based ◽  
Global Quality ◽  
Fuzzy Linguistic ◽  
The Web

The Web is changing the information access processes and it is one of the most important information media. Thus, the developments on the Web are having a great influence over the developments on others information access instruments as digital libraries. As the development of digital libraries is to satisfy user need, user satisfaction is essential for the success of a digital library. The aim of this paper is to present a model based on fuzzy linguistic information to evaluate the quality of digital libraries. The quality evaluation of digital libraries is defined using users' perceptions on the quality of digital services provided through their Websites. We assume a fuzzy linguistic modeling to represent the users' perception and apply automatic tools of fuzzy computing with words based on the LOWA and LWA operators to compute global quality evaluations of digital libraries. Additionally, we show an example of application of this model where three Spanish academic digital libraries are evaluated by fifty users.

QUALITY OF ECONOMIC AND PRODUCTION MANAGEMENT: PRACTICE, QUESTIONS OF THEORY

2021 ◽  
Vol 1 (8) ◽  
pp. 12-19
Author(s):  
V. G. VERSAN ◽  
Keyword(s):  
Economic Development ◽  
Production Management ◽  
Management Practice ◽  
Management Model ◽  
Global Trends ◽  
Model Based ◽  
Socio Economic Development ◽  
Practice Questions

The article notes the low quality of economic and production management in Russia. The reasons for this and ways to eliminate them are established. It is shown that the global trends of socio-economic development are not fully reflected in the theory of economic and production management. The ways of developing a management model based on improving the quality of interaction between people and economic entities are proposed. The concept of interaction in relation to socio-economic processes is revealed. The ways of minimizing management costs are considered.

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