Influence of the air pressure and oil amount to the temperature of the high-speed bearings lubricated by oil mist

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Miloš Stanković ◽  
Nenad Kolarević ◽  
Nikola Davidovic ◽  
Marko Miloš
Keyword(s):  
High Speed ◽  
Design Methodology ◽  
Experimental Approach ◽  
Air Pressure ◽  
Jet Engine ◽  
Content Type ◽  
Custom Made ◽  
Bearing Assembly ◽  
Oil Mist ◽  
Lubrication Conditions

Purpose The purpose of this paper is to improve the lubrication and remove as much as possible of the heat generated in the bearing assembly, embedded in the jet engine. Design/methodology/approach To determine the necessary values of the air pressure and oil amount, an experimental approach is used. For that purpose, a custom made test rig is developed. Findings Less amount of oil makes better lubrication conditions, reflected in the smaller temperature of the bearings. Concerning the air pressure, too high and too low air pressure deteriorates the lubrication parameters. An optimum value should be determined experimentally. The influence of oil amount is remarkably bigger than the influence of air pressure. Originality/value This experimental investigation provides an easy and fast way to improve the high-speed bearings lubrication parameters.

Comparison of the reluctance laminated and solid rotor synchronous machine operating at high temperatures

2019 ◽  
Vol 38 (4) ◽  
pp. 1111-1119 ◽  
Author(s):  
Marcin Lefik ◽  
Krzysztof Komeza ◽  
Ewa Napieralska-Juszczak ◽  
Daniel Roger ◽  
Piotr Andrzej Napieralski
Keyword(s):  
High Speed ◽  
Design Methodology ◽  
Three Dimensional ◽  
Synchronous Machine ◽  
Point Of View ◽  
Heat Sources ◽  
Model Calculations ◽  
Content Type ◽  
Thermal Phenomenon ◽  
Practical Implications

Purpose The purpose of this paper is to present a comparison between reluctance synchronous machine-enabling work at high internal temperature (HT° machine) with laminated and solid rotor. Design/methodology/approach To obtain heat sources for the thermal model, calculations of the electromagnetic field were made using the Opera 3D program including effect of rotation and the resulting eddy current losses. To analyse the thermal phenomenon, the 3D coupled thermal-fluid (CFD) model is used. Findings The presented results show clearly that laminated construction is much better from a point of view of efficiency and temperature. However, solid construction can be interesting for high speed machines due to their mechanical robustness. Research limitations/implications The main problem, despite the use of parallel calculations, is the long calculation time. Practical implications The obtained simulation and experimental results show the possibility of building a machine operating at a much higher ambient temperature than it was previously produced for example in the vicinity of the aircraft turbines. Originality/value The paper presents the application of fully three-dimensional coupled electromagnetic and thermal analysis of new machine constructions designed for elevated temperature.

Variety perception and attitude toward digital assortments

2019 ◽  
Vol 47 (12) ◽  
pp. 1353-1363 ◽  
Author(s):  
Yolande Piris ◽  
Nathalie Guibert
Keyword(s):  
Design Methodology ◽  
Positive Attitude ◽  
Experimental Approach ◽  
Product Category ◽  
Experimental Conditions ◽  
Content Type ◽  
Perceptions And Attitudes ◽  
Practical Implications ◽  
Real Product ◽  
The Way

Purpose The purpose of this paper is to investigate consumers’ variety perception for online grocery assortments and, more generally, to better understand consumers’ attitude toward digital assortments. In particular, this research examines the influence of the organization of products that results from assortment structure and display. Design/methodology/approach Starting from the observation that previous work on traditional assortments is not sufficient to understand consumers’ perceptions and attitudes, the paper adopts a hypothetico-deductive approach and develops four hypotheses. These hypotheses are tested using an experimental approach. Findings This research enables us to see that both attitude and variety perception are affected by the way products are organized on a website. Furthermore, contrary to what the literature on traditional assortments allows one to assume, the assortment corresponding to a more positive attitude is not perceived as being the more varied. As a result, our findings reconsider the link between variety perception and consumer assortment evaluation for digital assortments. Research limitations/implications The work is based on data collected for only one product category. It would be interesting to explore other categories also, to determine if the structure of the assortment and variety perception have stable effects. Practical implications The results inform retailers that they must carefully design the display of their digital assortments. If a retailer wants to enhance variety perception, the authors recommend using an assortment organized by brand, or presenting all the products together. If, instead, the goal is to encourage a positive attitude, the retailer should opt for assortments sorted by attribute or that present all products together. Originality/value This research adopts a new orientation on assortment perception and evaluation, considering the specificities involved in digitizing assortments. In addition, this research studies a real product category and puts respondents in experimental conditions close to reality.

Using fractional order weakening buffer operator to forecast the main indices of online shopping in China

2019 ◽  
Vol 9 (1) ◽  
pp. 128-140 ◽  
Author(s):  
Xiao Hui Gao ◽  
Lifeng Wu
Keyword(s):  
Fractional Order ◽  
High Speed ◽  
Design Methodology ◽  
Online Shopping ◽  
Experimental Results ◽  
Order Number ◽  
Growth Trend ◽  
Content Type ◽  
Economic Indices ◽  
Expansion Period

Purpose The purpose of this paper is to predict the main economic indices of online shopping in China. Design/methodology/approach A fractional order weakening buffer operator (WBO) for the GM(1,1) model is put forward in order to solve the problem of limited nonlinear data. The order number of WBO can adjust in line with the scenario. Findings The experimental results indicate that the proposed method can consider the scenario and obtain more accurate forecasting results. Originality/value This study found that the slowdown of growth trend after the previous high speed expansion period will continue, and the online shopping sellers should make more efforts to develop potential consumers to increase its turnover.

Time pressure and improvisation: enhancing creativity, adaption and innovation at high speed

2015 ◽  
Vol 29 (6) ◽  
pp. 7-9 ◽  
Author(s):  
Josh Hodge ◽  
Vanessa Ratten
Keyword(s):  
Competitive Advantage ◽  
High Speed ◽  
Design Methodology ◽  
Time Pressure ◽  
Training Needs ◽  
Content Type

Purpose – Organizations are becoming more focused on time pressures when introducing innovation and creativity into their organizations. The purpose of this paper is to discuss the opportunity for organizations to focus on improvisation training as a way to gain a competitive advantage and leapfrog their competitors. Design/methodology/approach – This paper takes the approach of identifying a model of improvisation training for organizations that focuses on the convergence of planning and executive for promoting innovation training practices. Findings – This paper’s main findings are that the time pressures faced by organizations means that there is a funnel limiting the link between creativity, adaption and innovation. This means that improvisation training needs to be done quickly, and organizations need to act efficiently when introducing new practices. Originality/value – This paper’s key value is that organizations can use improvisers by using bricolage and ready-mades to take existing concepts and apply them to new situations.

Investigations on influence of groove shapes for the journal bearing in high-speed and heavy-load press system

2018 ◽  
Vol 70 (1) ◽  
pp. 230-240 ◽  
Author(s):  
Yu Chen ◽  
Yu Sun ◽  
Chunping Cao
Keyword(s):  
High Speed ◽  
Design Methodology ◽  
Journal Bearing ◽  
Computational Method ◽  
Hydrodynamic Characteristics ◽  
Hydrodynamic Behavior ◽  
Heavy Load ◽  
Content Type ◽  
Thermal Influence ◽  
Fluid Interaction

Purpose The purpose of this study is to investigate the hydrodynamic characteristics of journal bearings in a high-speed and heavy-load press system by considering thermal influence and cavitation. Design/methodology/approach A proper and effectual computational method is presented for steady-state analysis of fluid interaction in a rotor-bearing press system by combining computational fluid dynamics techniques. Findings The influences of eccentricity ratio, rotational speed and oil-film thickness on the hydrodynamic behavior of the journal bearing are studied. Originality/value The computational method can be used for creating a precise lubrication design for a journal bearing of a lubrication system.

A machine learning approach-based power theft detection using GRF optimization

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
A. Prakash ◽  
A. Shyam Joseph ◽  
R. Shanmugasundaram ◽  
C.S. Ravichandran
Keyword(s):  
Machine Learning ◽  
Transmission Lines ◽  
High Speed ◽  
Design Methodology ◽  
Learning Approach ◽  
Smart Meter ◽  
Financial Loss ◽  
Content Type ◽  
Garra Rufa ◽  
Machine Learning Approach

Purpose This paper aims to propose a machine learning approach-based power theft detection using Garra Rufa Fish (GRF) optimization. Here, the analyzing of power theft is an important part to reduce the financial loss and protect the electricity from fraudulent users. Design/methodology/approach In this section, a new method is implemented to reduce the power theft in transmission lines and utility grids. The detection of power theft using smart meter with reliable manner can be achieved by the help of GRF algorithm. Findings The loss of power due to non-technical loss is small by using this proposed algorithm. It provides some benefits like increased predicting capacity, less complexity, high speed and high reliable output. The result is analyzed using MATLAB/Simulink platform. The result is compared with an existing method. According to the comparison result, the proposed method provides the good performance than existing method. Originality/value The proposed method gives good results of comparison than those of the other techniques and has an ability to overcome the associated problems.

Drawing negative inferences from a positive country-of-origin image

2017 ◽  
Vol 34 (2) ◽  
pp. 293-310 ◽  
Author(s):  
Kashef A. Majid
Keyword(s):  
High Risk ◽  
Design Methodology ◽  
Experimental Approach ◽  
Low Cost ◽  
Country Of Origin ◽  
Consumer Perceptions ◽  
The Other ◽  
Content Type ◽  
The Usa ◽  
Country Of Origin Image

Purpose The purpose of this paper is to explore how a positive country-of-origin image will impact consumer perceptions for a high-risk product when the price is unexpectedly low. Design/methodology/approach An experimental approach was used with consumers from the USA and India. Consumers were divided into groups and given two scenarios that involved purchasing medicine that may have been counterfeit. In one scenario manufacturing took place in India, the other in Switzerland. They were asked to state the probability that certain goods could be counterfeit if they originated from the stated country and then make choices based on those perceived probabilities. An analysis of variance was conducted to test for differences between groups. Findings The authors found that in both samples consumers attached greater probabilities toward low-priced medicines if they originated from Switzerland vs India. Conversely, the higher priced medicines were more likely to be counterfeit if they originated from India vs Switzerland. When given a choice scenario consumers chose more versions of the cheaper products from India than from Switzerland. Originality/value When country-of-origin is salient then it is believed that a positive country-of-origin image will benefit products that are produced from that country. Consumers expect that more expensive products come from a country with a positive country-of-origin image. The results demonstrate that when there is a conflict between expectations of the country and the price of the product the outcome is lowered perceptions and consumption of the product. This holds true for consumers from a high-cost economy (USA) and consumers from a low-cost economy (India). The authors add to the literature on country-of-origin by demonstrating that a positive image can be a liability when consumers are wary of purchasing a high-risk product.

Hardware simulation of lane keeping assist based on sensor fusion

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Noor Cholis Basjaruddin ◽  
Edi Rakhman ◽  
Fazrin Adinugraha
Keyword(s):  
Sensor Fusion ◽  
High Speed ◽  
Design Methodology ◽  
Human Error ◽  
Fusion Method ◽  
Safety Index ◽  
Content Type ◽  
Speed Mode ◽  
Lane Keeping ◽  
Important System

PurposeSafety is one of the most crucial factors in transportation due to so many factors, including human-error, that might result in various small to fatal accidents. This is why lane keeping assist (LKA) is an important system that needs to be developed. LKA will prevent the vehicle from moving to another lane because the driver is negligent to maintain the direction of the vehicle.Design/methodology/approachIn this study, LKA works using camera and ultrasonic sensors. The data coming from these two types of sensors are then fused to determine how should the car reacts to some certain situation so that it stays on the lane. The sensor fusion method was used to further ensure the car's safety.FindingsThe results of the hardware simulation show that LKA can successfully avoid the car from getting off the lane with safety index of 95% for high-speed mode and 100% for medium and low-speed mode; meanwhile on the use of ultrasonic sensor, the speed of the car is adjusted to the distance of the car's side disturbance.Originality/valueThis research has succeeded in simulating a sensor fusion–based LKA system.

Felt discrimination increases offensiveness of stereotyped out-group depictions

2015 ◽  
Vol 32 (1) ◽  
pp. 26-33
Author(s):  
Roland L Leak ◽  
Omar P Woodham ◽  
George W Stone
Keyword(s):  
Factor Analysis ◽  
Design Methodology ◽  
Experimental Approach ◽  
Minority Groups ◽  
Content Type ◽  
Dependent Variables ◽  
Group Members ◽  
Independent Variable ◽  
Past Experiences ◽  
Issue Relevance

Purpose – This paper aims to investigate the effects of minorities’ who experienced discrimination on perceptions of offensiveness tied to brand imagery that stereotypically depicts other minorities classified as out-group members. Design/methodology/approach – Study 1 utilizes factor analysis to develop dependent variables, and a path analysis to model relationships between the focal independent variable (IV) and dependent variable (DVs). Study 2 uses an experimental approach analyzing data with ANOVA and bootstrapping methodologies. Findings – Minorities who report experiencing more discrimination perceive more offensiveness tied to branding containing overt stereotypical depictions of out-groups. This effect is mediated through a perceived sympathy for the out-group. However, while some minorities perceive these branded logos as relatively more offensive, minorities, as a group, do not perceive these stereotyped logos as overly offensive. Research limitations/implications – Minorities not depicted in or alluded to in stereotypical imagery associated with a brand may be a valuable consumptive bloc that can be recruited to oppose such uses of stereotypes. This research highlights that any sympathy that these minorities report holding for depicted minority groups may be important to future targeted communications. Brand managers may need to aggressively defend the brand against negative attributions derived from non-depicted minorities’ felt sympathy. Depicted minorities fighting to remove stereotypical imagery in brands may be able to leverage non-depicted minorities’ expressed sympathy to form coalitions. Depicted minorities’ communications, however, may need to increase issue relevance to non-depicted minorities. Originality/value – This research explores how non-affected groups perceive stereotypes infused in branding. It demonstrates that, depending on past experiences, these individuals may defend against a perceived social threat targeted at a societal out-group.

scholarly journals Application of complex network theory in identifying critical elements of CRH2 train system

2020 ◽  
Vol 2 (1) ◽  
pp. 35-52
Author(s):  
Huiru Zhang ◽  
Limin Jia ◽  
Li Wang ◽  
Yong Qin
Keyword(s):  
Complex Network ◽  
Network Theory ◽  
High Speed ◽  
Design Methodology ◽  
Content Type ◽  
Complex Network Theory ◽  
Critical Elements ◽  
Advantages And Disadvantages ◽  
Train Operation ◽  
Train System

Purpose Based on complex network theory, a method for critical elements identification of China Railway High-speed 2 (CRH2) train system is introduced in this paper. Design/methodology/approach First, two methods, reliability theory and complex theory, are introduced, and the advantages and disadvantages for their application in identifying critical elements of high-speed train system are summarized. Second, a multi-layer multi-granularity network model including virtual and actual nodes is proposed, and the corresponding fusion rules for the same nodes in different layers are given. Findings Finally, taking CRH2 train system as an example, the critical elements are identified by using complex network theory, which provides a reference for train operation and maintenance. Originality/value A method of identifying key elements of CRH2 train system based on integrated importance indices is introduced, which is a meaningful extension of the application of complex network theory to identify key components.

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