scholarly journals Chamber Optimization for Comprehensive Improvement of Cone Crusher Productivity and Product Quality

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Fengbiao Wu ◽  
Lifeng Ma ◽  
Guanghui Zhao ◽  
Zhijian Wang

This study aims to analyze the impact of key structural parameters such as the bottom angle of the mantle, the length of the parallel zone, and the eccentric angle on the productivity and product quality of the cone crusher and optimize the crushing chamber to improve the crusher performance. The amount of ore in the blockage layer was calculated by analyzing the movement state of the ore in the crushing chamber. Considering the amount of ore uplift further, the traditional mathematical model of crusher productivity was revised. Then, a mathematical model for dual-objective optimization of productivity and product quality of cone crusher was established. Furthermore, taking the existing C900 cone crusher as the research object, the influence of key parameters on the performance of the crusher was researched. And the optimal values of key structural parameters were obtained. Finally, based on the iron ore coarsely crushed by the gyratory crusher, the dynamic characteristics of the C900 cone crusher were simulated by using the discrete element method (DEM), and the simulation results are basically consistent with the numerical analysis results. Results show that considering the amount of ore uplift in the blockage layer, the revised mathematical model of crusher productivity can better characterize the actual productivity. The bottom angle of the mantle and the length of the parallel zone are within the range of 50°–60°and 140 mm–190 mm, respectively. The productivity shows a positive correlation with the bottom angle and a negative correlation with the length of the parallel zone. But the dependence of product quality on the angle and the length is just the opposite. The eccentric angle is within the range of 1.4°–2° and its decrease has a negative effect on the productivity and product quality.

GIS Business ◽  
2019 ◽  
Vol 14 (4) ◽  
pp. 85-98
Author(s):  
Idoko Peter

This research the impact of competitive quasi market on service delivery in Benue State University, Makurdi Nigeria. Both primary and secondary source of data and information were used for the study and questionnaire was used to extract information from the purposively selected respondents. The population for this study is one hundred and seventy three (173) administrative staff of Benue State University selected at random. The statistical tools employed was the classical ordinary least square (OLS) and the probability value of the estimates was used to tests hypotheses of the study. The result of the study indicates that a positive relationship exist between Competitive quasi marketing in Benue State University, Makurdi Nigeria (CQM) and Transparency in the service delivery (TRSP) and the relationship is statistically significant (p<0.05). Competitive quasi marketing (CQM) has a negative effect on Observe Competence in Benue State University, Makurdi Nigeria (OBCP) and the relationship is not statistically significant (p>0.05). Competitive quasi marketing (CQM) has a positive effect on Innovation in Benue State University, Makurdi Nigeria (INVO) and the relationship is statistically significant (p<0.05) and in line with a priori expectation. This means that a unit increases in Competitive quasi marketing (CQM) will result to a corresponding increase in innovation in Benue State University, Makurdi Nigeria (INVO) by a margin of 22.5%. It was concluded that government monopoly in the provision of certain types of services has greatly affected the quality of service experience in the institution. It was recommended among others that the stakeholders in the market has to be transparent so that the system will be productive to serve the society effectively


2015 ◽  
Vol 778 ◽  
pp. 259-263
Author(s):  
Fa Jun Zhang ◽  
Lin Zi Li ◽  
Hui Lin ◽  
Yin Lin Pu ◽  
Zhu Xin

Various uncertain factors affect the movement of the welding robot, thus welding gun tend to deviate from the theory of welding position which reduces the welding accuracy, of which the revolute pair clearance have an greater effect on the movement of the welding robot. In order to study the influence of revolute pair clearance to the end pose accuracy of welding robot, the mathematical model of revolute pair clearance was established, and the software SolidWorks was used for establishing the welding robot model, making simulations of the mechanical arm with joint clearance and no joint clearance. At last, the movement characteristic of the hinge shaft is attained. The simulation results showed that the shaft velocity and displacement of mechanical arm with joint clearance has a certain degree of fluctuation, which affecting the end pose accuracy of welding robot , and reducing the movement stability and the welding accuracy of welding robot.


2021 ◽  
Vol 26 (5) ◽  
pp. 399-409
Author(s):  
M.A. Zapletina ◽  
◽  
S.V. Gavrilov ◽  
◽  

One of the main advantages of FPGA and CPLD is the high development speed; therefore, the importance of effective computer-aided design tools for modern microcircuits of these classes cannot be overestimated. Placement and routing are the most time-consuming stages of FPGA/CPLD design flow. The quality of results of these stages is crucial to the final perfor-mance of custom digital circuits implemented on FPGA/CPLD. The paper discusses an approach to accelerating the routing stage within the layout synthesis flow for FPGA/CPLD by introducing a few algorithmic improvements to a routing procedure. The basic routing algorithm under study is a modified Pathfinder for a mixed routing resource graph. Pathfinder is a well-known negotiation-based routing algorithm that works on the principle of iteratively eliminating congestions of chip routing resources. For experiments, the sets of test digital circuits ISCAS'85, ISCAS'89, LGSynth'89 and several custom industrial projects were used. The impact of the proposed algorithmic improvements was analyzed using four FPGA/CPLD architectures. It has been established that due to the improvements of the algorithm proposed in the paper, the average reduction in routing time was from 1.3 to 2.6 times, depending on the FPGA/CPLD architecture, with no significant negative effect on the timing characteristics of the designed circuits.


2017 ◽  
Vol 46 (2) ◽  
pp. 224-241 ◽  
Author(s):  
Jacob R. Fooks ◽  
Kent D. Messer ◽  
Joshua M. Duke ◽  
Janet B. Johnson ◽  
Tongzhe Li ◽  
...  

This study uses an experiment where ferry passengers are sold hotel room “views” to evaluate the impact of wind turbines views on tourists’ vacation experience. Participants purchase a chance for a weekend hotel stay. Information about the hotel rooms was limited to the quality of the hotel and its distance from a large wind turbine, as well as whether or not a particular room would have a view of the turbine. While there was generally a negative effect of turbine views, this did not hold across all participants, and did not seem to be effected by distance or hotel quality.


Author(s):  
Mykhailo Demydenko ◽  
Ihor Pistunov

The competitiveness of an insurance company depends on the competitiveness of the products and services it introduces in the market. The competitive advantages of the insurance company are expressed in the attractiveness and competitiveness of insurance policies. An economic and mathematical model of increasing the competitiveness of the insurance company is proposed, which allows to calculate the integrated indicator of competitiveness of the insurance policy based on a comprehensive system of indicators characterizing the reliability of the insurance company, quality of its services, competitiveness, social activity. To analyze the impact of these indicators on the competitiveness of the insurance policy and identify areas for improving the efficiency and competitiveness of the insurance company. The competitiveness of an insurance company depends on the competitiveness of the products and services it introduces in the market. The assessment of the quality of insurance company services is compliance with the needs, requirements, and insurance interests of customers. This assessment is performed each time an individual client chooses to cooperate with an insurance company that meets his insurance interests and wishes. Therefore, the overall competitiveness of the enterprise depends on the competitiveness of products and services offered on the market. The competitive advantages of the insurance company are expressed in the attractiveness and competitiveness of insurance policies. The insurance market in recent years has shown consistently high growth, which makes it attractive for doing business. In these conditions, the task of modeling the activities of the insurance company in a highly competitive market environment becomes relevant. A mathematical model of increasing the competitiveness of the insurance company is proposed, which allows to calculate the integrated indicator of competitiveness of the insurance policy based on a comprehensive system of indicators characterizing the reliability of the insurance company, quality of its services, competitiveness, social activity. With the proposed model, insurance companies can objectively assess their weaknesses and strengths to ensure continuous growth and decent competition in a competitive market environment. The model allows you to select performance indicators and perform modeling and determine the consequences of changes in this indicator, analyze the impact of these indicators on the competitiveness of insurance policies and identify areas for improving the efficiency and competitiveness of the insurance company. By conducting such experiments, insurance companies can make more informed choices and decisions, analyze areas of competitiveness, and more efficiently allocate resources.


With traffic increase in a wireless network beyond its capacity and as the number of connected devices continue to grow, the quality of service (QoS) degrades. In this paper we study the impact of mobility on throughput in the case of an infrastructure wireless network using IEEE 802.11 Wi-Fi standard. Since we found in the literature that the mobility of stations can have an impact on the quality of service, we try to remedy to this by implementing a new access category reserved for mobile stations. First we compare the throughput between static and mobile nodes, both connected to a QoS station. Then we propose our new model that consists of adding a new access category used by mobile nodes regardless of their traffic category. The study was made by simulating different scenarios using Network Simulator-3 (NS-3). We found that the throughput may vary depending on the simulation scenario. The simulation results show that with the proposed solution the mobile nodes can have a better throughput.


2022 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Esmeralda Crespo-Almendros ◽  
M. Belén Prados-Peña ◽  
Lucia Porcu ◽  
Juan Miguel Alcántara-Pilar

Purpose This study seeks to analyze the influence of the consumer's perceived benefits deriving from two different promotional incentives offered via social media on the perceived quality of the heritage complex.Design/methodology/approach A quasi-experimental study was carried out among online users, implementing two different promotional stimuli. Facebook was selected as the social network through which the promotional incentives were offered in the experiment. The sample was obtained via a panel of Internet users provided by Sondea Internet SL.Findings The results showed that the benefits perceived by the tourists will depend on the sales promotion type offered. On the one hand, free VIP pass was found to be mostly related to hedonic benefits that positively affect perceived quality. On the other hand, 2 × 1 offer would be perceived as a utilitarian benefit and is likely to exert a fairly negative effect on perceived quality.Practical implications Tourism managers and practitioners are encouraged to analyze the characteristics of certain types of sales promotions, as each promotional incentive bears different values and associated benefits. The findings of this study suggest managers and practitioners to implement non-monetary promotions to enhance brand equity and perceived quality. Thus, it is paramount for the managers of cultural institutions and heritage sites to trust in sales promotions which can be very helpful if they are designed carefully.Originality/value This study pioneers the analysis of the impact of the benefits associated with different typologies of sales promotions on social networks on the perceived quality of a heritage site.


Author(s):  
Andrzej Zyluk ◽  
Konrad Czernikiewicz ◽  
Joanna Antoniak ◽  
Urszula Abramczyk

Abstract Background Microsurgery is a specific surgical expertise that involves operating on very small structures, and requires the assistance of a magnifying device: a microscope or loupes. Several factors have been identified that could affect the quality of microsurgical performance in training or surgical procedures. Objective The objective of this study was to assess the impact of the selected factors – caffeine, alcohol and physical exercise – on a microsurgical task prior its performance. Methods Ten students from the 5th and 6th years of medical studies who had completed the advanced microsurgical course performed a “6-stitches test” on a latex glove spanned over a cup prior to and after consumption of caffeine, alcohol and performing physical exercises. The times taken to complete the task at baseline and post-exposure were recorded. Results The results of the study show a statistically significant positive effect of caffeine and a statistically significant negative effect of physical exercise on microsurgical performance when performed shortly before the task. Small dose of alcohol taken before the task showed had little effect on performance.


Author(s):  
E. V. Romanova

We studied the effect of the antimicrobial drug «Multiomycin 1 %» on the hematological and biochemical pa-rameters of blood, the activity of digestive enzymes (amylase, alkaline phosphatase, protease), the structure of the mi-crobiocenosis of the small and large intestines, and the quality of the products. Based on the results of preclinical stud-ies, a production test was carried out in conjunction with the veterinary drug «Yuberin oral», as well as an assessment of the impact on the productivity of poultry was given. «Multiomycin 1 %» did not adversely affect the chickens. The drug had a positive effect on the activity of the digestive processes, increased their activity. Contributed to a decrease in the total microbial contamination in the contents of the small and large intestines and an increase in the content of bifidobacteria and lactobacilli. Combined use with yuberin contributed to an increase in safety, an increase in the aver-age daily gain, as well as a decrease in the incidence of gastroenteritis. The weight gain at the end of the experiment in the chickens of the experimental group was 3,74 % higher than in the control. The use of the veterinary drug «Multiomycin 1 %» did not have a negative effect on the quality of the products.


2021 ◽  
pp. 027507402110530
Author(s):  
Marco Tulio Zanini ◽  
Carmen Migueles ◽  
Juliana Carvalho

Previous research has shown that cutbacks in public spending often impact the range and quality of the public services delivered, leading to negative behaviors on the part of public servants. This article examines how sudden cutbacks caused by a major state financial crisis have an impact on interpersonal trust within a special police unit. We present the results of a longitudinal case study using a combination of qualitative methods. The lack of foreseeability and reliability caused by drastic changes resulting from cutbacks has a negative effect on members’ trust in their capacity to perform.


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