scholarly journals Comparative Research on the Rebound Effect in Direct Electromagnetic Forming and Indirect Electromagnetic Forming with an Elastic Medium

Materials ◽  
2018 ◽  
Vol 11 (8) ◽  
pp. 1450 ◽  
Author(s):  
Xianlong Liu ◽  
Liang Huang ◽  
Hongliang Su ◽  
Fei Ma ◽  
Jianjun Li
Keyword(s):  
Elastic Medium ◽  
High Speed ◽  
Rebound Effect ◽  
Influence Factors ◽  
Skin Depth ◽  
Electromagnetic Forming ◽  
Forming Quality ◽  
Driver Plate ◽  
The Impact

In the process of electromagnetic forming (EMF), the rebound effect caused by high speed collision between sheet and die will affect the fittability, which results in a bad forming quality of workpiece. In this paper, finite element models of direct EMF and indirect EMF with an elastic medium are established, the influence factors of fittability in indirect EMF are studied, the two forming processes are compared, and the mechanisms of reduced rebound effect in indirect EMF are revealed. The results show that: in indirect EMF, with the increase of the discharging voltage or thickness of rubber, the fittability increases and then decreases; when the thickness of driver plate is equal to the skin depth of the driver plate, the fittability is the best. The optimal process parameters of indirect EMF are as follows: the discharging voltage is 10 kV, the thickness of the rubber is 20 mm and the thickness of driver plate is 2 mm. The rebound effect in indirect EMF is reduced compared with direct EMF for the following reasons: the impact force caused by the collision between the sheet and die is balanced by the pressure provided by the rubber; the sheet is always under tensile stress state due to the friction force provided by rubber; the remaining kinetic energy of sheet after collision with the die is absorbed by rubber. Therefore, the rebound effect in indirect EMF is suppressed compared with direct EMF. So, the fittability of the workpiece is improved, which results in a better forming quality.

The Impact of Offset Paper on Ink Transfer Rate and Ink Absorption Rate

2012 ◽  
Vol 560-561 ◽  
pp. 506-509
Author(s):  
Zhi Jian Li ◽  
Qing Jun Meng ◽  
Liang Liu
Keyword(s):  
Transfer Rate ◽  
Absorption Rate ◽  
Influence Factors ◽  
Ink Transfer ◽  
The Impact

The ink transfer rate and ink absorption rate directly affects the quality of printing matter, so it is very important to know the influence factors of the ink transfer rate and ink absorption rate. This paper studied on the impact of offset paper smoothness and offset paper absorbency on the ink transfer rate, the impact of offset paper compactness and offset paper absorbency on the ink absorption rate. The results show that ink transfer rate is affected by offset paper smoothness within a certain range. The ink transfer rate is affected greatly by offset paper absorbency. The ink absorption rate is greatly affected by offset paper compactness and absorbency.

The Influence Factors of Silicon Steel Magnetic Property

2014 ◽  
Vol 884-885 ◽  
pp. 345-348 ◽  
Author(s):  
Lei Shang ◽  
Hai Li Yang ◽  
Hong Xu ◽  
Yun Gang Li
Keyword(s):  
Magnetic Properties ◽  
Magnetic Property ◽  
Chemical Composition ◽  
Influence Factors ◽  
Dimensional Accuracy ◽  
Silicon Steel ◽  
Factors Affecting ◽  
Size Type ◽  
The Impact

Magnetic properties of silicon steel mainly depend on the internal organizational structure and chemical composition. The main factors affecting magnetic properties of silicon steel are analyzed and summarized, including grain size, inclusions (size, type, quantity, and morphology), crystal texture, internal stress, dimensional accuracy, the surface quality of steels, and chemical composition. The impact mechanism of the factors influencing silicon steel magnetic property is explained and these influence factors are interrelated.

Flexibility Analysis of the Cross Axis and Furcated Frame in the Spatial 4-Bar Linkage Weft Insertion Mechanism

2012 ◽  
Vol 627 ◽  
pp. 435-438 ◽  
Author(s):  
Lei Zhang ◽  
Ke Long Yu
Keyword(s):  
High Speed ◽  
Component Material ◽  
Insertion Mechanism ◽  
The Cross ◽  
Cross Axis ◽  
Map Analysis ◽  
Four Bar Linkage ◽  
Relationship Of ◽  
The Impact

In this paper, the flexibility of the cross axis and furcated frame of high speed rapier loom was considered through the change of the two components’ material. Corresponding neutral documents were generated in ANSYS, then with the ANSYS-ADAMS co-simulation, those neutral documents were imported into ADAMS. The motion curves of sword belt were received. Through the map analysis and comparison, the relationship of changing the two components’ material and the motion curves of sword belt were found. The simulation results show that, in consideration of the flexible components, rational selection of the component material can greatly reduce the impact on Spatial four bar linkage weft insertion mechanism, thereby enhance the quality of the fabric.

Research on the Impact of Vent Pressure on the Yarn Splicing Based on ANSYS

2013 ◽  
Vol 584 ◽  
pp. 50-53
Author(s):  
De Gong Chang ◽  
Deng Chen Li ◽  
Song Mei Li ◽  
Guang Zhen Zhou ◽  
Hai Xia Zhao
Keyword(s):  
Driving Force ◽  
High Speed ◽  
Structure Design ◽  
Hole Diameter ◽  
Ansys Software ◽  
Modeling Analysis ◽  
Solid Foundation ◽  
The Impact ◽  
Chamber Diameter

Pneumatic splice makes use of high-speed compressed air as the driving force to complete the yarn splicing, noticing that the change of the vent pressure has a significant effect on yarn splicing. This paper studies the impact of vent pressure on the quality of yarn splicing when twisting and untwisting. Modeling, analysis and simulation of the air splice is done with the integration of Pro/E and ANSYS software, to study the flow filed and obtain the influence on the speed and pressure of the inside the splicing chamber when changing the speed and pressure while keeping the diameter of splicing chamber diameter, the vent hole diameter and the relative angle are unchanged. The results of the analysis of the air splice will lay a solid foundation for the further optimized structure design.

scholarly journals Performance Analysis on Multiple Device Connections of Small Office Home Office Network

2021 ◽  
Vol 18 (4(Suppl.)) ◽  
pp. 1457
Author(s):  
Muhamad Nur Ashaari ◽  
Murizah Kassim ◽  
Ruhani Ab. Rahman ◽  
Abd Razak Mahmud
Keyword(s):  
Performance Analysis ◽  
Packet Loss ◽  
High Speed ◽  
Network Performance ◽  
Network Services ◽  
Quality Of Services ◽  
Home Office ◽  
Internet Connections ◽  
The Impact

Malaysia has been supported by one of the high-speed fiber internet connections called TM UniFi. TM UniFi is very familiar to be used as a medium to apply Small Office Home Office (SOHO) concept due to the COVID-19 pandemic. Most of the communication vendors offer varieties of network services to fulfill customers' needs and satisfaction during the pandemic. Quality of Services is queried by most users by the fact of increased on users from time to time. Therefore, it is crucial to know the network performance contrary to the number of devices connected to the TM UniFi network. The main objective of this research is to analyze TM UniFi performance with the impact of multiple device connections or users' services. The study was conducted to analyze the QoS on its traffic, packets transfer, RTT, latency, and throughput. Wireshark simulation program has been used as a network traffic capture where PCAP files have been analyzed by using PCAP Analyzer for Splunk. Traffic filtering has been enabled to capture selected traffic to measure network performance. The result shows that better network performance can be achieved if a smaller number of devices are connected at the same time.  The percentage of packet loss, RTT, latency is increased when more users connected at the same time. The throughput also shows a decrease for multi-device connections. Based on the analysis it can be concluded that TM UniFi still can provide good network services for the SOHO network environment and sufficient bandwidth despite the rapid user growth in Malaysia.

Steer the Rheology of Solvent with Little Surfactant to Exfoliate MoS2 Nanosheet by Liquid Phase Exfoliation Method

NANO ◽  
2020 ◽  
Vol 15 (10) ◽  
pp. 2050118
Author(s):  
Dan Zhou ◽  
Jianzhong Yin
Keyword(s):  
High Speed ◽  
2D Materials ◽  
Ultrasonic Bath ◽  
Mos2 Nanosheet ◽  
Alcohol Mixtures ◽  
Liquid Phase Exfoliation ◽  
The Impact ◽  
Shear Thinning Fluid ◽  
Statistical Results

A surfactant system L64 and alcohol mixture was employed to exfoliate MoS2. To reduce the impact of surfactant on the quality of the nanosheet, the concentration of L64 was decreased to an extremely low value 0.0325 mM. Utilize common ultrasonic bath, the production yield of the nanosheet was increased to about 5% per hour, and statistical results from AFM showed that 40% of the nanosheet were less than 4 nm thick. Rheology characterization showed that surfactant alcohol mixtures were shear thinning fluid, yet the viscosity of L64 system varies directly with the shear rate in the high-speed shear region (higher than 400 s−1), and further affect the shear strength, therefore viscosity at high-speed shear can be considered as an indicator of the effectiveness for the exfoliation system. Exfoliated MoS2 was evaluated by hydrogen evolution reaction, and compared to the bulk MoS2, the 4 wt% Pt/FL-MoS2 improved the overpotential from 366 mV to 273 mV at 10 mA[Formula: see text]cm[Formula: see text]. This study presented a facile and effective route to fabricate 2D MoS2 with much less residue, and bring more opportunities to exploit clean and nontoxic system to exfoliate 2D materials.

Active Control of Fuzzy for High-Speed Pantograph

2012 ◽  
Vol 251 ◽  
pp. 158-163 ◽  
Author(s):  
Gang Yang ◽  
Zhong Mei Dai ◽  
Fu Li ◽  
Zheng Zhi Luo
Keyword(s):  
Active Control ◽  
Contact Force ◽  
High Speed ◽  
Fuzzy Controller ◽  
Current Collection ◽  
Maximum Value ◽  
Dynamic Performances ◽  
Catenary System ◽  
The Impact

The regular current collection is very important for high-speed train， and can be obviously improved by the use of active control. In order to study the impact of the fuzzy active control on pantograph-catenary system, the model ohe simulation model is created with the software of simulink. Finally the influences of fuzzy active control on dynamic performances and quality of current collection of the pantograph-catenary system are analyzed. It seems that, the performances of the system with or without active control is established, the fuzzy controller is constructed, and tf the pantograph- catenary system can be improved obviously under the fuzzy active control, the maximum value of the contact force is reduced to 50 percent, the minimum is increased to 80 percent, and the fluctuation extent of the contact force is reduced to 70 percent.

2 × 20 Gbit/s OFDM-based FSO transmission system for HAP-to-ground links incorporating mode division multiplexing with enhanced detection

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Praveen M ◽  
Vasudevan B ◽  
Ransom R
Keyword(s):  
Orthogonal Frequency Division Multiplexing ◽  
High Speed ◽  
Input Power ◽  
Transmission System ◽  
Space Optics ◽  
Mode Division Multiplexing ◽  
Power Divergence ◽  
The Impact ◽  
Root Module

AbstractIn this work, the integration of free-space optics (FSO) technology for implementing long-haul high-altitude platform (HAP)-to-ground transmission system is proposed. Mode division multiplexing (MDM) and orthogonal frequency division multiplexing (OFDM) are incorporated for carrying high-speed signals without interference. The impact of increasing input power, divergence angle, antenna diameter, and attenuation on the system performance is further investigated. In addition, the performance of the MDM-OFDM-HAP-to-ground FSO transmission system is improved by using a square root module at the receiver for link reach enhancement. The results exhibit a reliable transportation of 40 Gbps information over 20 km FSO distance with good quality of the received signal.

scholarly journals The Impact of High-Speed Railway on China’s Regional Economic Growth Based on the Perspective of Regional Heterogeneity of Quality of Place

2021 ◽  
Vol 13 (9) ◽  
pp. 4820
Author(s):  
Shanlang Lin ◽  
Prithvi Raj Dhakal ◽  
Zhaowei Wu
Keyword(s):  
Economic Growth ◽  
High Speed ◽  
Regional Economic Growth ◽  
High Speed Railway ◽  
Regional Economic ◽  
Fixed Assets ◽  
Quality Of Place ◽  
Investment In Fixed Assets ◽  
The Impact

Transport enables trade between people, which is essential for the development of civilizations. Transport is a crucial necessity for specialization, allowing production and consumption of products to occur at different locations. High-speed rail (HSR) allows the flow of people between regions, cities, countries. With rapid global development in HSR technology for passenger transportation, it plays a vital role in transportation systems. The improvement of the quality of cities with different emphasis will bring different economic development results. Therefore, exploring the impact of high-speed railways and quality of place on economic development is necessary. This paper takes the prefecture-level city with a high-speed railway opened in 2008–2013 as the research sample and takes other prefecture-level cities in the country as the control group. The study findings revealed that employment, investment in fixed assets, average wage, and higher education institute significantly affect China’s regional economic growth. Institute of higher education reflects the negative effect on the regional economic growth whereas the employment, investment in fixed assets, and average wage rate positively impact it. Based on the results, it can be concluded that China’s regional economy is significantly affected by its quality.

scholarly journals Method for Monitoring and Increasing the Quality of Experience in Cellular Networks Based on Interconnections Between Key Quality Indicators Using Spline-Approximation

2020 ◽  
Author(s):  
Jamil Al Azzeh ◽  
Roman Odarchenko ◽  
Anastasiia Abakumova ◽  
Serhii Bondar
Keyword(s):  
Service Quality ◽  
Cellular Networks ◽  
Quality Indicators ◽  
High Speed ◽  
Spline Approximation ◽  
Large Data ◽  
Assessment System ◽  
Distinct Advantage ◽  
The Impact

Abstract Sustainable and balanced development of the communications industry is inextricably linked with increasing numbers of subscribers and services provided. The current level of development of the cellular services market, qualitative changes in the means and methods of providing services, and the increased volume and diversity of information circulating in cellular networks have evoked the need for service quality assessment system improvement. To maintain competitiveness, the main efforts of operators are aimed at improving quality and increasing the service life of subscribers in the network by ensuring the required level of customer satisfaction in high quality services through a system of organizational-technical and socio-economic measures to bring the achieved level of quality of service (QoS) provision in accordance with the existing, emerging, or projected needs of subscribers. These circumstances determine the relevance of the studied tasks related to the assessment and management of the quality of cellular services and the development of approaches to their solution.To achieve improved QoS provision, a functional relationship between network parameters has been established, i.e., the impact of key performance indicators on a key quality indicator through the use of cubic Hermitian splines (CHS) has been determined. The use of splines, as a signal model, can significantly improve the quality of signal processing due to the continuity of values and partial derivatives in the joints of spline gluing. CHS are characterized by calculation simplicity, as they provide high speed computing, which, in turn, is important for real time work when processing large data sets. Experimentally, it was shown that the use of splines allows for the ability to calculate statistical estimates of the required parameters of spline approximations, but also their confidence intervals, which increases the accuracy and probability of further calculations and is a distinct advantage of this approachThe methods of service quality management through machine learning have been improved, which are effective tools for modeling integrated indicators of communication services quality control, monitoring their condition in terms of final copies of services, determining the causes of degradation, and reporting. It monitors the service performance provided by the cellular operator. In addition, the method checks the readiness and availability of services, detects network nodes through which quality degradation occurs, collects various quality metrics, and compares them with pre-installed quality indicators.

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