3D tolerance modeling and geometric precision analysis of plane features for flexible parts

2018 ◽  
Vol 35 (7) ◽  
pp. 2557-2576 ◽  
Author(s):  
Xiaokai Mu ◽  
Qingchao Sun ◽  
Wei Sun ◽  
Yunlong Wang ◽  
Chuanhua Wang ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Mechanical System ◽  
Least Square ◽  
Ideal Element ◽  
Content Type ◽  
Geometric Tolerance ◽  
Influence Mechanism ◽  
Geometric Precision ◽  
Mating Surface ◽  
Flexible Parts

PurposeThe traditional precision design only takes the influence of geometric tolerance of the parts and does not involve the load deformation in the assembly process. This paper aims to analyze the influence mechanism of flexible parts deformation on the geometric precision, and then to ensure the reliability and stability of the mechanical system.Design/methodology/approachFirstly, this paper adopts the N-GPS to analyze the influence mechanism of flexible parts deformation on the geometric precision and constructs a coupling 3D tolerance mathematical model of the geometric tolerance and the load deformation deviation based on the SDT theory, homogeneous coordinate transformation theory and surface authentication idea. Secondly, the least square method is used to fit the deformation surface of the mating surface under load so as to complete the conversion from the non-ideal element to the ideal element.FindingsThis paper takes the horizontal machining center as a case to obtain the deformation information of the mating surface under the self-weight load. The results show that the deformation deviation of the parts has the trend of transmission and accumulation under the load. The terminal deformation cumulative amount of the system is up to –0.0249 mm, which indicated that the influence of parts deformation on the mechanical system precision cannot be ignored.Originality/valueThis paper establishes a comprehensive 3D tolerance mathematical model, which comprehensively considers the effect of the dimensional tolerance, geometric tolerance and load deformation deviation. By this way, the assembly precision of mechanical system can be accurately predicted.

Proprietary information and the cost of bank debt

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
HyunJun Na
Keyword(s):  
Least Square ◽  
Bank Loan ◽  
Content Type ◽  
Loan Contracts ◽  
Proprietary Information ◽  
Banking Deregulation ◽  
Interstate Banking ◽  
Innovative Firms ◽  
Bank Loan Contracts ◽  
The Impact

PurposeThis study explores how the firm’s proprietary information has an impact on the bank loan contracts. It explains the propensity of using the competitive bid option (CBO) in the syndicate loans to solicit the best bid for innovative firms and how it changes based on industry competition and the degree of innovations. This research also examines how the interstate banking deregulation (Interstate Banking and Branching Efficiency Act) in 1994 affected the private loan contracts for innovative borrowers.Design/methodology/approachThe study uses various econometric analyses. First, it uses the propensity score matching analysis to see the impact of patents on pricing terms. Second, it uses the two-stage least square (2SLS) analysis by implementing the litigation and non-NYSE variables. Finally, it studies the impact of the policy change of the Interstate Banking and Branching Efficiency Act of 1994 on the bank loan contracts.FindingsFirms with more proprietary information pays more annual facility fees but less other fees. The patents are the primary determinants of the usage of CBO in the syndicate loans to solicit the best bid. While innovative firms can have better contract conditions by the CBO, firms with more proprietary information will less likely to use the CBO option to minimize the leakage of private information and the severe monitoring from the banks. Finally, more proprietary information lowered the loan spread for firms dependent on the external capital after the interstate banking deregulation.Originality/valueThe findings of this research will help senior executives with responsibility for financing their innovative projects. In addition, these findings should prove helpful for the lawmakers to boost economies.

The parameter identification model considering both geometric parameters and joint stiffness

2019 ◽  
Vol 47 (1) ◽  
pp. 76-81
Author(s):  
Jing Bai ◽  
Le Fan ◽  
Shuyang Zhang ◽  
Zengcui Wang ◽  
Xiansheng Qin
Keyword(s):  
Parameter Identification ◽  
Industrial Robot ◽  
Joint Stiffness ◽  
Geometric Parameters ◽  
Least Square ◽  
Experimental Result ◽  
Positional Accuracy ◽  
Content Type ◽  
The Absolute ◽  
Identification Model

Purpose Both geometric and non-geometric parameters have noticeable influence on the absolute positional accuracy of 6-dof articulated industrial robot. This paper aims to enhance it and improve the applicability in the field of flexible assembling processing and parts fabrication by developing a more practical parameter identification model. Design/methodology/approach The model is developed by considering both geometric parameters and joint stiffness; geometric parameters contain 27 parameters and the parallelism problem between axes 2 and 3 is involved by introducing a new parameter. The joint stiffness, as the non-geometric parameter considered in this paper, is considered by regarding the industrial robot as a rigid linkage and flexible joint model and adds six parameters. The model is formulated as the form of error via linearization. Findings The performance of the proposed model is validated by an experiment which is developed on KUKA KR500-3 robot. An experiment is implemented by measuring 20 positions in the work space of this robot, obtaining least-square solution of measured positions by the software MATLAB and comparing the result with the solution without considering joint stiffness. It illustrates that the identification model considering both joint stiffness and geometric parameters can modify the theoretical position of robots more accurately, where the error is within 0.5 mm in this case, and the volatility is also reduced. Originality/value A new parameter identification model is proposed and verified. According to the experimental result, the absolute positional accuracy can be remarkably enhanced and the stability of the results can be improved, which provide more accurate parameter identification for calibration and further application.

Customer satisfaction with sommelier services of upscale Chinese restaurants in Hong Kong

2019 ◽  
Vol 31 (4) ◽  
pp. 532-554 ◽  
Author(s):  
Tommy Lau ◽  
Man Lai Cheung ◽  
Guilherme D. Pires ◽  
Carol Chan
Keyword(s):  
Hong Kong ◽  
Customer Satisfaction ◽  
Service Quality ◽  
Customer Loyalty ◽  
Positive Impact ◽  
Partial Least Square ◽  
Least Square ◽  
Survey Method ◽  
Content Type ◽  
The Impact

Purpose The abolishment of the wine tax in Hong Kong has led to increased wine consumption and increased demand for wine-related professionals, such as sommeliers. Yet the importance of sommeliers’ value-adding performance in the context of upscale Chinese restaurants has not been examined. To address this gap, the SERVQUAL framework is adopted to examine the influence of sommeliers’ service quality (SQ) on customer satisfaction (CS) and loyalty in the context of upscale Chinese restaurants in Hong Kong. Design/methodology/approach The survey method is used to collect data from 302 units of the population of interest, partial least square-structural equation modelling (PLS-SEM) is used to test the links between constructs. Findings Four of the seven dimensions of sommeliers’ service quality, namely, empathy, tangibles, credibility and assurance, have a significant positive impact on customer satisfaction and customer loyalty, whereas the impact of perceived value and responsiveness on customer satisfaction and customer loyalty is positive but only marginally significant. Reliability has a weak and non-significant impact on customer satisfaction and customer loyalty. Research limitations/implications Examining a small number of upscale Chinese restaurants in Hong Kong limits generalisation of the findings to other contexts. Replication of the research in different contexts will enhance generalizability. In terms of implications, the discussion highlights the importance of sommeliers’ service performance on customers’ SQ perceptions SQ, CS and loyalty, all of which are important variables for restaurateurs. Originality/value To the best of the authors’ knowledge, this is the first study of the influence of the quality of sommelier’s SQ on CS and loyalty in upscale Chinese restaurants in Hong Kong. Given the lack of attention to this service role in the literature, the study contributes theory from which further understanding can develop.

Do the calendar anomalies still exist? Evidence from Indian currency market

2016 ◽  
Vol 42 (2) ◽  
pp. 136-150 ◽  
Author(s):  
Satish Kumar ◽  
Rajesh Pathak
Keyword(s):  
Least Square ◽  
January Effect ◽  
Currency Markets ◽  
Content Type ◽  
Currency Market ◽  
Before And After ◽  
Calendar Anomalies ◽  
Ordinary Least Square Regression ◽  
The 2008 Financial Crisis ◽  
Using Data

Purpose – The purpose of this paper is to examine the presence of the day-of-the-week (DOW) and January effect in the Indian currency market for selected currency pairs; USD-(Indian rupee) INR, EUR-INR, GBP-INR and JPY-INR, from January, 1999 to December, 2014. Design/methodology/approach – Ordinary least square regression analysis is used to examine the presence of DOW and January effect to test the efficiency of the Indian currency market. The sample period is later divided into two sub-periods, that is, pre- and post-2008 to capture the behavior of returns before and after the 2008 financial crisis. Further, the authors also use the non-parametric technique, the Kruskal-Wallis test, to provide robustness check for the results. Findings – The results indicate that the returns during Monday to Wednesday are positive and higher than the returns on Thursday and Friday which show negative returns. The returns during January are found to be higher than the returns during rest of the year. Further, all currencies exhibit significant DOW and January effects in pre-crisis period, however, post-crisis; these effects disappear for all currencies indicating that the markets have become more efficient in the later time. The findings can be further attributed to the increased intervention in the forex markets by the Reserve Bank of India after the crisis. Practical implications – The results have important implications for both traders and investors. The findings suggest that the investors might not be able to earn excess profits by timing their positions in some particular currencies taking the advantage of DOW or January effect which in turn indicates that the currency markets have become more efficient with time. The results are in conformity with those reported for the developed markets. The results might be appealing to the practitioners as well in a way that they can consider the state of financial market for financial decision making. Originality/value – The authors provide the first study to examine the calendar anomalies (DOW and January effect) across a range of emerging currencies using 16 years of data from January, 1999 to December, 2014. To the best of the authors’ knowledge, no study has yet examined these calendar anomalies in the currency markets using data which covers two important periods, pre-2008 and post-2008.

The Control of Vibration Transmissibility Using an Electrodynamic Actuator –Close-Loop Solution

2013 ◽  
Vol 436 ◽  
pp. 166-173
Author(s):  
A. Mihaela Mîţiu ◽  
Daniel Constantin Comeagă ◽  
Octavian G. Donţu
Keyword(s):  
Mathematical Model ◽  
Control System ◽  
Mechanical System ◽  
Closed Loop ◽  
Mechanical Systems ◽  
Vibration Transmissibility ◽  
Technical Solutions ◽  
The Mathematical Model

In this paper are presented some aspects of transmissibility control of mechanical systems with 1 DOF so that the effects of vibration on their action to be minimized. Some technical solutions that can be used for this purpose is analyzed. Starting from the mathematical model of an electro-mechanical system with 1 DOF, are identified the parameters which influence the effectiveness of the transmissibility control system using an electrodynamic actuator who work in "closed loop".

Tacit knowledge transfer in coopetition

2017 ◽  
Vol 10 (4) ◽  
pp. 453-468 ◽  
Author(s):  
Amit Kumar ◽  
Swarup Kumar Dutta
Keyword(s):  
Knowledge Transfer ◽  
Tacit Knowledge ◽  
Least Square ◽  
Service Firms ◽  
Content Type ◽  
Ordinary Least Square ◽  
Tacit Knowledge Transfer ◽  
Potential Benefits ◽  
Ordinary Least Square Regression ◽  
Empirical Context

Purpose The purpose of this paper is to understand how firms affiliated to business groups (BGs) are able to improve their innovation capability (IC) when engaged in coopetition (collaboration between competing firms). This study aims to explore the relationship between coopetitive relationship strength (CRS), the extent of tacit knowledge transfer (TKT) and IC as well as examine the moderating effect of both BG affiliation and coopetitive experience. Design/methodology/approach The paper examines inter-firm relationships within the empirical context of Indian manufacturing and service firms, by adopting (ordinary least square) regression analysis to test the various hypotheses. The central thesis is that the TKT in coopetition constitutes an important driver to the IC. Findings The paper provides some evidence that inter-firm CRS influences the extent of TKT, and the extent of TKT affects firm IC. The results support that firms in coopetition gain more if their coopetitive partner has a BG affiliation. In absence of a BG affiliation of any of the coopetitive partners, the buildup of TKT reduces as CRS is increased. Research limitations/implications Additional large-sample of data may attempt to validate relationships. The study, however, did not consider all enablers that are critical for TKT. Despite these limitations, analysis provides important and novel perspectives. Practical implications The paper contributes to develop executives’ practices in understanding potential benefits of coopetitive relationship. The implications of this research are important for managers seeking understanding of the management of coopetition. Originality/value The paper makes a modest attempt to investigate the various scenarios of the presence or absence of the moderation of BGs and its impact on CRS in the buildup of TKT. This is the first attempt to link coopetition to the TKT in the BG literature. This study also contributes to our understanding of coopetition in a non-western context.

Research on Generator Excitation Parameter Identification - PSS Low-Pass Link Parameter Identification

2013 ◽  
Vol 805-806 ◽  
pp. 716-720
Author(s):  
Tao Xu ◽  
Tian Long Shao ◽  
Dong Fang Zhang
Keyword(s):  
Mathematical Model ◽  
Parameter Identification ◽  
Least Squares Method ◽  
Least Square Method ◽  
Least Square ◽  
National Standards ◽  
Matlab Software ◽  
Low Pass ◽  
Newton Iterations ◽  
The Mathematical Model

Combined with the contents of the study-PSS low-pass link parameter identification. Least-squares method is selected. Using least-square method for PSS low-pass link mathematical model are also deduced. For the results, because of the mathematical model is solving nonlinear equations, cannot used by the Newton method directly. So we choose to use Newton iterations, with this feature, choose to use MATLAB software to solve the equation. Identification of the use of MATLAB software lags after the PSS parameters obtained recognition results compared with national standards, identifying and verifying the practicability.

Macroeconomic fundamentals and dynamics of the Indian rupee-dollar exchange rate

2015 ◽  
Vol 7 (4) ◽  
pp. 301-326 ◽  
Author(s):  
Chandan Sharma ◽  
Rajat Setia
Keyword(s):  
Exchange Rate ◽  
Structural Break ◽  
Cointegration Analysis ◽  
Least Square ◽  
Dollar Exchange Rate ◽  
Content Type ◽  
Macroeconomic Variables ◽  
Indian Rupee ◽  
Macroeconomic Fundamentals ◽  
The Impact

Purpose – This paper aims to examine the relationship between Indian rupee-US dollar exchange rate and the macroeconomic fundamentals for the post-economic reform period. Design/methodology/approach – The authors have used an empirical model which includes a range of important macroeconomic variables based on the basic monetary theories of exchange rate determination. At the first stage of the analysis, they have tested structural break in the data. Subsequently, they have employed the fully modified ordinary least square, Wald’s coefficient restriction and impulse response functions (IRF) to estimate the monetary model in the long- and short-run horizons. Findings – Results of analyses indicate that the macroeconomic fundamentals determine exchange rate in a significant way, but their effect varies sizably across the periods. The IRF illustrate the importance of interest rate in controlling exchange rate volatility. Practical implications – The analysis of the behavior of inter-relationship among macroeconomic variables will help policymakers in a deep-rooted understanding of this complex and time-varying relationship. Originality/value – Most of the existing studies have tested the impact of a single or a few macroeconomic fundamentals on exchange rate. But in the present study, we have tested the impact of a range of important variables, i.e. money supply, real income or output, price level and trade balance. Further, considering the importance of structural breaks in data, they authors have employed standard tests of structural break and incorporated the issue in the cointegration analysis.

Fractional order generalized thermoelastic response in a half space due to a periodically varying heat source

2018 ◽  
Vol 14 (1) ◽  
pp. 2-15 ◽  
Author(s):  
Jitesh Tripathi ◽  
Shrikant Warbhe ◽  
K.C. Deshmukh ◽  
Jyoti Verma
Keyword(s):  
Mathematical Model ◽  
Heat Source ◽  
Laplace Transform ◽  
Half Space ◽  
Fractional Order ◽  
Order Parameter ◽  
Order Theory ◽  
Numerical Inversion ◽  
Content Type ◽  
Copper Material

Purpose The present work is concerned with the solution of a fractional-order thermoelastic problem of a two-dimensional infinite half space under axisymmetric distributions in which lower surface is traction free and subjected to a periodically varying heat source. The thermoelastic displacement, stresses and temperature are determined within the context of fractional-order thermoelastic theory. To observe the variations of displacement, temperature and stress inside the half space, the authors compute the numerical values of the field variables for copper material by utilizing Gaver-Stehfast algorithm for numerical inversion of Laplace transform. The effects of fractional-order parameter on the variations of field variables inside the medium are analyzed graphically. The paper aims to discuss these issues. Design/methodology/approach Integral transform technique and Gaver-Stehfast algorithm are applied to prepare the mathematical model by considering the periodically varying heat source in cylindrical co-ordinates. Findings This paper studies a problem on thermoelastic interactions in an isotropic and homogeneous elastic medium under fractional-order theory of thermoelasticity proposed by Sherief (Ezzat and El-Karamany, 2011b). The analytic solutions are found in Laplace transform domain. Gaver-Stehfast algorithm (Ezzat and El-Karamany, 2011d; Ezzat, 2012; Ezzat, El Karamany, Ezzat, 2012) is used for numerical inversion of the Laplace transform. All the integrals were evaluated using Romberg’s integration technique (El-Karamany et al., 2011) with variable step size. A mathematical model is prepared for copper material and the results are presented graphically with the discussion on the effects of fractional-order parameter. Research limitations/implications Constructed purely on theoretical mathematical model by considering different parameters and the functions. Practical implications The system of equations in this paper may prove to be useful in studying the thermal characteristics of various bodies in real-life engineering problems by considering the time fractional derivative in the field equations. Originality/value In this problem, the authors have used the time fractional-order theory of thermoelasticity to solve the problem for a half space with a periodically varying heat source to control the speed of wave propagation in terms of heat and elastic waves for different conductivity like weak conductivity, moderate conductivity and super conductivity which is a new and novel contribution.

Institutional context and hotel social responsibility

Kybernetes ◽  
2014 ◽  
Vol 43 (3/4) ◽  
pp. 413-426 ◽  
Author(s):  
María Dolores Sánchez-Fernández ◽  
Alfonso Vargas-Sánchez ◽  
Paula Remoaldo
Keyword(s):  
Social Responsibility ◽  
Institutional Theory ◽  
Geographical Area ◽  
Institutional Context ◽  
Theoretical Framework ◽  
Northern Region ◽  
Structural Equations ◽  
Partial Least Square ◽  
Least Square ◽  
Content Type

Purpose – The authors want to study the connection between institutional theory and corporate social responsibility (CSR) in the set of hotels with three, four and five star situated in Galicia (Spain) and in the Northern region of Portugal. The authors aim to see whether there is a contrast of isomorphic behaviour in the institutional context of both regions. Design/methodology/approach – A quantitative study in which the authors apply the partial least square (PLS) technique, a methodology based on structural equations models using the software Visual-PLS. The authors intend to study the relationships between the pressures of institutional context and CSR practices, together with the relationship between legitimacy and these practices. The focus of the proposed model is based on the system theory. Findings – The main findings of this research clearly show that hotels are incorporated into an institutional context marked by enforced and regulatory pressures. Research limitations/implications – The proposed research model can be replicated using other units of study, sectors, geographic areas, among others, due to the explanatory capacity of the theoretical framework used. Originality/value – The originality of this work derives from the main contributions based on the theoretical framework (institutional theory and CSR), the object of study and geographical area (three, four and five star hotels located in Galicia and in the North of Portugal), the context (economic crisis), the field of study (private sphere) and the type of organizations (profit making).

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