scholarly journals ДОСЛІДЖЕННЯ ВПЛИВУ ЗМІЩЕННЯ ПАКУВАННЯ ВЗДОВЖ ОСІ БОБІНОТРИМАЧА НА КРИТИЧНІ ШВИДКОСТІ

2020 ◽  
Vol 144 (2) ◽  
pp. 13-23
Author(s):  
Б. С. Завертанний ◽  
О. П. Манойленко ◽  
О. О. Акимов
Keyword(s):  
High Speed ◽  
Center Of Mass ◽  
Axial Direction ◽  
Dynamic Loads ◽  
Practical Significance ◽  
Stable Operation ◽  
Direct Drive ◽  
Critical Speeds ◽  
The Impact

Creation of a mathematical model of the mechanism of winding of rewinding machines, research of influence of size of shift of packing on critical speeds and development of recommendations for the decision of the set task. Method. When working out the thread for packaging, high-speed winding mechanisms are subject to high requirements, both for the quality of the resulting packaging and for the speed of the bobbin holder. When installing the spool on the spool holder, it is possible to shift it in the axial direction from the design position, which leads to a change in the position of the center of mass of the package with the spool, and in accordance with changes in dynamic loads on the spool holder. Therefore, there is a need to determine the magnitude of the impact of the displacement of the package along the axis of the bobbin holder on the operating speeds of the equipment and the quality of the resulting packages. In the winding process, the placement of the package on the bobbin holder of the winding mechanism of the rewinding machine plays an important role. The displacement of the center of mass of the package affects both the operating speed of the equipment and the quality of the package. In rewinding machines, a mechanism for controlling the thickness of the package is installed, which controls the speed processes during winding. When the coil is shifted towards the top of the cone, incomplete packing (less weight) is developed. When shifted to the side opposite the top of the packing cone, on the contrary, the weight of the packing increases. In addition, the magnitude of the displacement of the package affects the dynamic loads of the winding mechanism. Results. The influence of the magnitude of the packing displacement along the axis of the bobbin holder on the critical speeds of the winding mechanism and the quality of packing is determined. Scientific novelty. The study and analysis of the influence of the magnitude of the displacement of the bobbin with packaging on the critical speeds of the winding mechanism are conducted. The magnitude of the influence of the position of the masses of the center of the coil with packing relative to the bobbin holder on the value of the critical speeds of the winding mechanism is determined. The obtained results allow to control the range of working speeds of the winding mechanism depending on the parameters of the position of the spool on the spool holder, which can be used to adjust the speed of the winding process when packing the spool and make changes when designing the rewinding equipment. The method of determining the maximum possible speeds in the process of rewinding textile material on rewinding machines with direct drive of the bobbin, taking into account the position of the bobbin on the bobbin holder, which can be used in the design of new mechanisms or modernization of existing ones. Practical significance. A dynamic model of the winding mechanism has been developed. The magnitude of the influence of packing displacement on critical speeds is shown. Methods and designs for improving the quality of packaging and stable operation of equipment are proposed.

Does negative information in MD&A can reduce stock crash risk?

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Jianmai Liu
Keyword(s):  
Information Asymmetry ◽  
Information Disclosure ◽  
Stock Price ◽  
Negative Information ◽  
Bad News ◽  
Practical Significance ◽  
Crash Risk ◽  
Content Type ◽  
The Impact

Purpose As an important part of the disclosure of listed companies' annual reports, MD&A will disclose some "bad news" about the company. The purpose of this paper is to study whether such "bad news" can reduce information asymmetry and alleviate the risk of stock price crash remains to be seen. Design/methodology/approach Based on the sample of A-share listed companies from 2007 to 2016, the authors examine whether the negative information in MD&A could reduce stock price crash risk. Findings It is found that the negative information in MD&A does not reduce future crash, which indicates that the negative information in MD&A does not alleviate the information asymmetry. Further, it is also found this is due to the low readability of negative information which leads to the negative information not successfully released into the market timely. Only highly readable negative information can alleviate information asymmetry and suppress crash risk. In addition, the authors also find in the companies with more investor surveys negative tone is negatively correlated with crash risk, which means that investor surveys could help investors interpret the negative information in MD&A and alleviate stock price crash risk. Practical implications The practical significance of this article: this paper suggests that investors should carefully identify the quality of negative information in MD&A and pay attention to other quality characteristics besides credibility. This paper suggests that the regulator should pay attention not only to whether to disclose and the amount of disclosure but also to the quality of information disclosure, such as readability, so as to restrict management's strategic behavior in information disclosure. Originality/value First, different from previous studies on the impact of information disclosure on crash risk, this paper directly explores the impact of information in MD&A on stock price crash risk from the perspective of negative information disclosure that management most want to hide. It supplements the literature on the impact of information disclosure on stock price crash risk. Second, this paper studies the interaction between information tone and readability and its impact on the risk of stock price crash. Some studies believe that the credibility of negative news is higher and investors' reaction may be stronger. However, this paper finds that the disclosure of negative information may not be absorbed by the market because of the low readability. Third, this paper finds that investor surveys can help information users to interpret negative information and alleviate the risk of stock price crash, which shows that information disclosure of different channels will complement each other and improve information efficiency. Therefore, it advocates different information disclosure channels which has important practical significance for improving market pricing efficiency and reducing investment decision-making risk.

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.

Public interaction with judicial and law enforcement agencies: aspect of legal education

2020 ◽  
pp. 125-132
Author(s):  
Oleksandr Ostrohliad
Keyword(s):  
Legal Education ◽  
Point Of View ◽  
Practical Significance ◽  
Educational Services ◽  
Market Regulation ◽  
Law Enforcement Agencies ◽  
Legal Professions ◽  
The Difference ◽  
The Impact

Purpose. The aim of the work is to consider promising directions for reforming legal education in Ukraine, providing for the development of the corresponding conceptual framework. An indication of the gaps in the current legislation on the staffing of the main areas of legal activity. Focusing on the difference between the concepts of “right to education” and “access to a profession”, as well as the need for market regulation of the provision of educational services with the help of independent institutions. The methodology. The methodology includes a comprehensive analysis and generalization of the available scientific and theoretical material and the formulation of appropriate conclusions and recommendations. During the research, the following methods of scientific knowledge were used: terminological, logical-semantic, system-structural, logical-normative, comparative-historical. Results In the course of the study, it was determined that despite the fact that a draft Concept for the Development of Legal Education has been developed, its perfection from the point of view of the prospects for influencing the improvement of the quality of lawyers' training raises many objections. On the basis of a comparative study, it was determined that promising areas for improving the training of lawyers in Ukraine are: the activities of independent agencies to confirm the quality of the services provided, as well as the improvement of regulatory regulation, which implies access to the profession. Originality. In the course of the study, it was established that the improvement of the quality of training of lawyers in Ukraine should occur through natural development: a specially authorized body should establish only compliance with accreditation requirements; the institution of higher education must, taking into account the principle of autonomy, ensure an appropriate level of quality in the provision of educational services; access to certain legal professions requires significant procedural improvements. The draft Concept for the development of legal education at the moment needs substantial revision, as well as to provide an understanding of the impact of previous reform steps in the field of education, cannot be adopted in the near future. Practical significance. The results of the study can be used in law-making activities to improve the norms of the current legislation providing for access to legal professions, as well as for further scientific research of the problems of legal education in Ukraine.

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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