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1 – 10 of over 3000Wanxing Jiang, Ji Li, Haifeng Yan, Hao Li and Mengyuan Chen
The purpose of this paper is to investigate whether, when and how customer orientation may contribute to success in introduction of new products (SINP).
Abstract
Purpose
The purpose of this paper is to investigate whether, when and how customer orientation may contribute to success in introduction of new products (SINP).
Design/methodology/approach
With a multi-phase and multi-source data collection approach, this study tested the proposed theoretical model by applying multiple regression with SPSS Process Macro.
Findings
Customer orientation positively influences cross-functional integration (CFI), which in turn facilitates SINP; a firm’s new product introduction (NPI) strategy moderates customer orientation–CFI link.
Originality/value
This study empirically tests whether, why and when customer orientation may contribute to SINP. By suggesting the important role of customer orientation in improving SINP, the mediating effect of CFI and the moderating effect of NPI strategy, the current study should enrich the extant literature on customer orientation, CFI and NPI.
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Hao Li, Haipeng Geng and Hao Lin
The misalignment is generally inevitable in the process of machining and assembly of rotor systems with gas foil bearings, but the exploration on this phenomenon is relatively…
Abstract
Purpose
The misalignment is generally inevitable in the process of machining and assembly of rotor systems with gas foil bearings, but the exploration on this phenomenon is relatively less. Therefore, the purpose of this paper is to carry out the thermo-elastohydrodynamic analysis of the foil bearing with misalignment, especially the inhomogeneous foil bearing.
Design/methodology/approach
The rotor is allowed to misalign in two non-rotating directions. Then the static and dynamic performance of the inhomogeneous foil bearing is studied. The thermal-elastohydrodynamic analysis is realized by combining the Reynolds equation, foil deformation equation and energy equation. The small perturbation method is used to calculate the dynamic coefficients, then the critical whirl ratio is obtained.
Findings
The gas pressure, film thickness and temperature distribution distort when the misalignment appears. The rotor misalignment can improve the loading capacity but rise the gas temperature at the same time. Furthermore, the rotor misalignment can affect the critical whirl ratio which demonstrates that it is necessary to analyze the misalignment before the rotordynamic design.
Originality/value
The value of this paper is the exploration of the thermo-elastohydrodynamic performance of the inhomogeneous foil bearing with misalignment, the analysis procedure and the corresponding results are valuable for the design of turbo system with gas foil bearings.
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Keywords
Xiaoling Wang, Yingrui Hou, Guoqing Wang, Mudong Hao and Hao Li
The purpose of this paper is to illustrate the dependence of flexible-electronics properties on the metal conductor parameters, such as the width, thickness, connection length and…
Abstract
Purpose
The purpose of this paper is to illustrate the dependence of flexible-electronics properties on the metal conductor parameters, such as the width, thickness, connection length and inner meander radius of the conductor.
Design/methodology/approach
This paper uses the finite element method to simulate flexible electronics with a copper conductor attached to polyimide substrate under tension, by using different parameters of the conductor.
Findings
By careful variation of copper conductor parameters, the authors obtain an optimized structure that can undergo large deformations with small stress concentrations, lending convenience for packaging.
Originality/value
The authors have developed an optimization method for selecting metal conductor parameters in flexible electronics.
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Keywords
Hao Li, Peng Hai Geng and Hao Lin
The normal operation of a rotor system is generally vulnerable to misalignment between gas foil bearing (GFB) and rotor. However, most theoretical and experimental researches…
Abstract
Purpose
The normal operation of a rotor system is generally vulnerable to misalignment between gas foil bearing (GFB) and rotor. However, most theoretical and experimental researches about the characteristics of GFBs have ignored this phenomenon. Therefore, the main purpose of this paper is to evaluate the static and dynamic performance of GFBs considering misalignment.
Design/methodology/approach
The shaft is allowed to misalign in two directions. Then the variations of bearing load, friction force, restoring moment, stiffness and damping coefficients are thoroughly explored. The hydrodynamic pressure on the gas film is modeled with compressible Reynolds equation, and the deformation of the flexible bearing is calculated with finite element method. Small perturbation method is used to obtain the displacement and moment dynamic coefficients.
Findings
The film thickness and pressure distribution distort when misalignments appear. The inclination of GFBs can enhance the restoring moment to withstand the imposed misalignment. Furthermore, the simulation phenomenon demonstrates the misalignment around load direction should be avoided as much as possible, while a small value misalignment around another direction is allowed.
Originality/value
The value of this paper is the exploration of the influence of misalignments on the static and dynamic performance of the Generation II journal GFB.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-10-2019-0418/
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Zhentao Li, Xiaoli Yin, Jixiang Yue, Fuyu Liu, Muming Hao and Baojie Ren
The purpose of this paper is to study the effects of operating conditions including process coefficient, lubricant viscosity and cavitation pressure on the cavitation of spiral…
Abstract
Purpose
The purpose of this paper is to study the effects of operating conditions including process coefficient, lubricant viscosity and cavitation pressure on the cavitation of spiral groove liquid-film seal (SG-LFS).
Design/methodology/approach
A mathematical model of SG-LFS is established based on the JFO boundary and a relative density is introduced. The universal governing equation after a coordinate transformation is discretized by the FVM method and solved by the Gauss-Seidel relaxation scheme.
Findings
The results indicate that the two-dimensional size of cavitation and cavitation degree are affected significantly by the process coefficient and lubricant viscosity but the effect of cavitation pressure can be ignored.
Originality/value
The effect mechanisms of operating conditions on the cavitation of SG-LFS are studied by the JFO boundary and cavitation degree characterized by a relative density. The results presented are helpful to perfect and deeply understand the cavitation mechanism of liquid-film seal.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-03-2020-0083/
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Hui Li, Hao Li, Rongfeng Zhang, Yi Liu, Shemiao Qi and Heng Liu
The purpose of this paper is to introduce the structure design process of the cantilever spindle with limited installation space and wishing to increase its critical speed.
Abstract
Purpose
The purpose of this paper is to introduce the structure design process of the cantilever spindle with limited installation space and wishing to increase its critical speed.
Design/methodology/approach
In this paper, the finite element method was used to analyze the influence of the supporting stiffness and the structure of the spindle on the critical speed, and then the structure of the spindle was designed; moreover, the experiment was accomplished and the experiment results show that the spindle can work stably.
Findings
Through analyzing the influence of the supporting stiffness and the structure of the spindle on the critical speed, the following conclusions could be obtained: the shape of the first-mode is the bend vibration of the cantilever of the spindle; the first-order critical speed of the spindle gradually decreases with the diameter and length of the cantilever increasing; the first-order critical speed of the spindle increases with the depth and diameter of the blind hole increasing; and the experiment was accomplished and the experiment results show that the spindle can work stably.
Originality/value
In this paper, the finite element method was used to design the spindle of the testing machine, and satisfactory results were obtained. It can provide a theoretical reference for the design of a similar spindle.
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Keywords
Hao Li, Shuai Zhang, Zhiran Yi, Jie Li, Aihua Sun, Jianjun Guo and Gaojie Xu
This work aims to evaluate the influence of rheological properties of building materials on the bonding quality and ultimate tensile strength in the fused deposition modeling…
Abstract
Purpose
This work aims to evaluate the influence of rheological properties of building materials on the bonding quality and ultimate tensile strength in the fused deposition modeling (FDM) process, through the investigation of parts printed by semi-crystalline and amorphous resins. Little information is currently available about the influence of the crystalline nature on FDM-printed part quality.
Design/methodology/approach
Semi-crystalline polyamide 12 and amorphous acrylonitrile butadiene styrene (ABS) were used to assess the influence of rheological properties on bonding quality and the tensile strength, by varying three important process parameters: materials, liquefier temperature and raster orientation. A fractography of both tensile and freeze-fractured samples was also investigated.
Findings
The rheological properties, mainly the melt viscosity, were found to have a significant influence on the bonding quality of fused filaments. Better bonding quality and higher tensile strength of FDM parts printed with semi-crystalline PA12, as compared with amorphous ABS, are suggested to be a result of higher initial sintering rates owing to the lower melt viscosity of PA12 at low shear rates. Near-full dense PA12 parts were obtained by FDM.
Originality/value
This project provides a variety of data and insight regarding the effect of materials properties on the mechanical performance of FDM-printed parts. The results showed that FDM technique allows the production of PA12 parts with adequate mechanical performance, overcoming the greatest limitation of a dependence on amorphous thermoplastics as a feedstock for the production of prototypes.
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Hongtuo Liu, Fangwei Xie, Kai Zhang, Xinxing Zhang, Jin Zhang, Cuntang Wang and Hao Li
The shock absorber is an important component of vehicle suspension that attenuates the vehicle vibration. Its running state directly affects the performance of the vehicle…
Abstract
Purpose
The shock absorber is an important component of vehicle suspension that attenuates the vehicle vibration. Its running state directly affects the performance of the vehicle suspension. The purpose of this paper is to quantitatively study the relationship between damping characteristics and air chamber and oil properties in single-tube pneumatic shock absorber.
Design/methodology/approach
Combined with the principle of fluid dynamics and hydraulic transmission technology, the rebound stroke and compression stroke mathematical models, and damping characteristics simulation model are established to investigate the effect of the air chamber and oil property on damping characteristics.
Findings
Research results show that the initial pressure of the air chamber is the key parameter which influences the damping characteristics of the shock absorber. The change of the initial pressure has more impact on damping force, and less impact on the speed characteristic; the initial volume of the air chamber almost has no effect on the damping characteristics. The density and viscosity of the oil have certain influence on the damping characteristics. Therefore, selecting suitable damping oil is very important.
Originality/value
Using Matlab/Simulink software to build simulation models, its results are very accurate. The conclusions can provide a theoretical reference for the structure design of a single-tube pneumatic shock absorber.
Details
Keywords
Hui Li, Heng Liu, Hao Li, Shemiao Qi, Yi Liu and Fengtao Wang
The purpose of this paper is to investigate the effect of the cage-pocket wear on the dynamic behavior of the ball bearing.
Abstract
Purpose
The purpose of this paper is to investigate the effect of the cage-pocket wear on the dynamic behavior of the ball bearing.
Design/methodology/approach
Through analyzing the complicated relationship and interactions among the ball bearing elements, the dynamic modeling of the ball bearing was established considering the gravity, drag force from the oil, hydrodynamic effect on the cage and the dynamic simulations with different amounts of the cage-pocket wear loss of the ball bearing (BPWL) were obtained by solving the ball bearing dynamic equations using Runge–Kutta method.
Findings
The results show that the trajectory of the cage’s centroid presents two vibration modes with different amplitudes. In addition, those two different forms of trajectory of different amplitudes emerge alternatively with BPWL increase moreover the diameter of the trajectory decrease significantly with the BPWL increasing, which is consistent with the experimental result and last BPWL has lightly effect on the average skidding ratio of the cage, however, the BPWL would produce significant effects on the fluctuation of the skidding ratio, which can directly reflect the stability of motion to a certain extent.
Originality/value
Practice shows that the bearing failure resulting from the cage accounts for 25 per cent of the total failure of the rolling bearings. However, few discussions about how the wear of the cage-pocket would influence the dynamic characteristics of the cage. This study can provide important ideas for the design of bearing cage-pocket size and the fault identification of the ball bearing to decrease the failure rate caused by the cage.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-12-2019-0535/
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Keywords
Hao Li, Edward Jones and Pierre de Gioia Carabellese
The purpose of this paper is to investigate whether ex ante board connections and director retention result in agency costs to target company shareholders in the form of reduced…
Abstract
Purpose
The purpose of this paper is to investigate whether ex ante board connections and director retention result in agency costs to target company shareholders in the form of reduced payment in mergers and acquisitions transaction.
Design/methodology/approach
The authors employ detailed data of ex ante board connection and director retention in the mergers and acquisition in the UK from 1999 to 2015. Ex ante board connections are measured as proportion of target and acquirer companies’ directors worked on the same board at any time prior to the takeover, while director retention is measured as proportion of target companies’ directors remains on board after the takeover is completed. For mergers and acquisition payment characteristics, the authors examine takeover premium, cash payment percentage and offer price adjustment.
Findings
The authors find that ex ante board connections and director retention lead to reduced offer prices and lower proportions of cash payment. Notably, when there is no connection and target directors are not retained, the authors find that the bidding companies increase their final offer by £14m more than in other scenarios. The authors also document strong evidence that ex ante board connections lead to a higher probability of director retention.
Originality/value
The paper highlights that ex ante board connections and director retention will lead to a significant cost on target company shareholders. The authors recommend that a more detailed set of information on ex ante board connections and intended target board retention should be disclosed.
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