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This paper aims to provide an assembly method to improve cylindrical components assembly quality. The proposed method not only could be applied to tolerance allocation, but also could guide the assembly of cylindrical components.

The paper claims to provide a stack-build assembly method using a connective assembly model to take the location and orientation tolerances of a rotor stage into account. Through the separate analysis of the location and orientation tolerances propagation process in the assembly, the quality of the final assembly of the rotationally symmetric cylindrical components assembly could be improved by properly selecting component orientations to minimize the eccentric deviation in the assembly.

The effectiveness of the proposed stack-build assembly technique in improving the tolerance propagation in the assembly of cylindrical components was verified through experiments run with a measuring machine. A real aero-engine rotor was assembly using the proposed method; compared to the direct-build assembly technique, which had the component orientations without consideration, the stack-build assembly technique could be used to reduce the eccentric deviation in cylindrical components assembly by nearly 50 per cent.

Different with the old methods, the new method defined the tolerances in detail, such as perpendicularity and angle of the lowest point, and could guide the assembly by the features of surfaces on different components. Through measuring the special tolerances of surfaces on the components, the best assembly angle for each component could be obtained.

The purpose of this paper is to report experimental investigations performed to analyze the effect of process parameters on the shape accuracy of selective laser sintered (SLS) parts.

The effect of process parameters, namely build orientation, laser power, scan speed, cylinder diameter and build chamber temperature has been studied on shape accuracy by using geometric tolerances such as cylindricity and flatness. Central composite design (CCD) is used to plan the experiments and a second order regression model has been developed to predict flatness and cylindricity. The significance of process variables on flatness and cylindricity has been evaluated using analysis of variance technique.

It is observed that interaction effects are more dominant than individual effects. In case of cylindricity, it is found that the interaction between the scan speed and orientation is the dominant factor next to the orientation and quadratic effect of the geometry. In case of flatness, the interaction between build chamber temperature and scan speed is the dominant factor.

The empirical models presented in this paper work within the range of values used for the experiments and most of these models need to be redeveloped for use with other materials.

The empirical models developed in this work would be useful in deciding the process parameters for parts with improved geometrical tolerances. The optimum parameters identified from the empirical model are found to yield accurate parts with minimum shape error.

The paper establishes the interactions between this build orientation, geometry and process parameters on the shape accuracy of SLS process.

The 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.

Firstly, 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.

This 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.

This 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.

We analyze the correlation between the political orientation of investors and their financial risk tolerance. Assessing financial risk tolerance is a very important aspect to developing an appropriate long‐term investing strategy. Our study is based on a sample of 129 undergraduates at Central Michigan University during one academic year. We employ a two‐axis political compass to determine the political orientation of our study participants. We determine their financial risk tolerance by analyzing their portfolios and trading behavior in a simulated investment game in a semester long course. We report two main findings: (1) financial risk tolerance is highest for those with more conservative economic political views and (2) financial risk tolerance is highest for those with more centrist social political views. We believe our results can help investment advisors and individual investors better assess individual financial risk tolerance through the use of the two‐axis political compass utilized in our study.

The idea of customer orientation is widely recognized by service people. However, there has been a lack of investigation into how the recognition of customer orientation may affect the service people's attitudes toward customer misconducts. As a result, our knowledge about the potential impacts of customer orientation philosophy on the ethical decisions made by service people could be insufficient. Hence, by using the life insurance salespeople in Taiwan as an example, the purpose of this paper is to investigate service people's tolerance of two types of customer misconduct (opportunistic frauds and planned frauds) and how those service people would react to the customer misconduct based on their marketing philosophy (customer orientation), perceived fraud size and perceived social consensus.

The sample of this study comes from life insurance companies in Taiwan. Questionnaires have been used as a data gathering instrument.

The results showed that customer orientation of the responders is negatively associated with the responders’ tolerance of the customer claim frauds. The responders’ unethical decision is most significantly influenced by perceived fraud size and social consensus.

The duties of insurance salespeople include helping customers settle insurance claims. However, insurance salespeople's tolerance of customer claim frauds is less mentioned in the insurance literature. Few studies have examined the relationship among customer orientation, social consensus and insurance salespeople's tolerance of customer claim frauds.

Polychronicity is the extent to which people prefer to be engaged in two or more tasks simultaneously. Relationships between polychronicity and four variables were examined in data from four samples totaling 1,173 participants. Only one statistically significant relationship occurred between polychronicity and propensity for creativity after controlling for other variables. Consistent significant relationships were found, however, between polychronicity and orientation to change (positive), tolerance for ambiguity (positive), and organizational attractiveness (positive or negative depending on whether the organization demonstrated a high or low level of polychronicity, respectively). Concatenated replications reproduced each of these three relationships in at least two samples.

The purpose of this paper is to apply the statistical tolerancing technique to analyze the dual responses of APFA arm height deviation with respect to next stage of disk assembly process and simultaneously optimize and allocate the required tolerance of the responses onto its components at minimum cost of manufacturing and the quality loss.

The relationships between the dual responses of APFA heights and the geometric dimensions and tolerances of APFA components, and orientation of the assembled part with respect to disk assembly were first defined. The effects of the APFA orientation, and the component tolerances on the distributions and variations of the responses were derived and investigated in terms of resultant product/process performance, quality loss, and the cost of assembly. The tolerance cost-based objective function is then formulated as the combined manufacturing/assembly cost and the quality loss. Direct search method was used to find the best feasible tolerance solutions satisfying the required product performance at minimum cost.

The constructed relationship or transfer functions of the dual responses were probabilistic depending on the orientation of part with respect to the next assembly process. The Monte Carlo simulation is empirically suitable for the computation of the conditional distributions of the responses against the first-order linear approximation of component variances. The proposed solution of tolerance control plan increases the product performances, C _pm , from 0.6 to be at least 1. The proposed tolerance allocation plans will reduce the amount of rework currently as high as 5 percent to at most 0.01 percent with minimally increased assembly cost.

This proposed methodology to design and allocate component tolerances is suitable and applicable to the APFA assembly process. The derived assembly functions of probabilistic type relating the responses to the process and component characteristics can represent the actual dynamic of assembled part better than a traditional single deterministic function developed under static concept. This presented methodology can be applied to other assembly cases where quality characteristic depends on the part dynamic.

This research simultaneously optimized the dual APFA height deviation responses with minimum cost of tolerance and quality loss using two different conditional distributions and transfer functions of the resultant deviations generated from dynamic of APFA with respect to disk.

This paper develops the statistical error analysis model for assembling, to derive measures of controlling the geometric variations in assembly with multiple assembly stations, and to provide a statistical tolerance prediction/distribution toolkit integrated with CAD system for responding quickly to market opportunities with reduced manufacturing costs and improved quality. First the homogeneous transformation is used to describe the location and orientation of assembly features, parts and other related surfaces. The desired location and orientation, and the related fixturing configuration (including locator position and orientation) are automatically extracted from CAD models. The location and orientation errors are represented with differential transformations. The statistical error prediction model is formulated and the related algorithms integrated with the CAD system so that the complex geometric information can be directly accessed. In the prediction model, the manufacturing process (joining) error, induced by heat deformation in welding, is taken into account.

The purpose of this paper is to carry out a tolerance analysis with geometric tolerances by means of the Jacobian model. Tolerance analysis is an important task to design and to manufacture high-precision mechanical assemblies; it has received considerable attention by the literature. The Jacobian model is one of the methods proposed by the literature for tolerance analysis. The Jacobian model cannot deal with geometric tolerances for mechanical assemblies. The geometric tolerances may not be neglected for assemblies, as they significantly influence their functional requirements.

This paper presents how it is possible to deal with geometric tolerances when a tolerance analysis is carried out by means of a Jacobian model for a 2D and 3D assemblies for which the geometric tolerances applied to the components involve only translational deviations. The three proposed approaches modify the expression of the stack-up function to overcome the shortage of Jacobian model that the geometric error cannot be processed.

The proposed approach has been applied to a case study. The results of the case study show how, when a statistical approach is implemented, the Jacobian model with the three developed methods gives results very similar to those due to other models of the literature, such as vector loop and variational.

In particular, the proposed approach may be applied only when the applied geometrical tolerances involve translational variations in 3D assemblies.

Tolerance analysis is a valid tool to foresee geometric interferences among the components of an assembly before getting the physical assembly. It involves a decrease of the manufacturing costs.

The original contribution of the paper is due to three methods to make a Jacobian model able to consider form and geometric deviations.

Addresses the need for a unified product information model and presents a new representation scheme for mechanical component modelling using shells as its principal geometric primitives for modelling form features. The representation scheme was implemented using the ACIS geometric modeller and C++ on a SUN SPARC/10 station. The advantage of using shells is that both surface and volume information of a form feature can be derived from a shell. Different levels of product data representation can be integrated into a single model. Therefore, it allows the user to model the geometry effectively and form features of a mechanical part on one system.