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The purpose of this paper is to present eight local elasto‐plastic beam element formulations incorporated into the corotational framework for two‐noded three‐dimensional beams. These formulations capture the warping torsional effects of open cross‐sections and are suitable for the analysis of the nonlinear buckling and post‐buckling of thin‐walled frames with generic cross‐sections. The paper highlights the similarities and discrepancies between the different local element formulations. The primary goal of this study is to compare all the local element formulations in terms of accuracy, efficiency and CPU‐running time.

The definition of the corotational framework for a two‐noded three‐dimensional beam element is presented, based upon the works of Battini .The definitions of the local element kinematics and displacements shape functions are developed based on both Timoshenko and Bernoulli assumptions, and considering low‐order as well as higher‐order terms in the second‐order approximation of the Green‐Lagrange strains. Element forces interpolations and generalized stress resultant vectors are then presented for both mixed‐based Timoshenko and Bernoulli formulations. Subsequently, the local internal force vector and tangent stiffness matrix are derived using the principle of virtual work for displacement‐based elements and the two‐field Hellinger‐Reissner assumed stress variational principle for mixed‐based formulations, respectively. A full comparison and assessment of the different local element models are performed by means of several numerical examples.

In this study, it is shown that the higher order elements are more accurate than the low‐order ones, and that the use of the higher order mixed‐based Bernoulli element seems to require the least number of FEs to accurately model the structural behavior, and therefore allows some reduction of the CPU time compared to the other converged solutions; where a larger number of elements are needed to efficiently discretize the structure.

The paper reports computation times for each model in order to assess their relative efficiency. The effect of the numbers of Gauss points along the element length and within the cross‐section are also investigated.

Reports on a new methodology for formation of virtual (“extended”) machining cells using generic capability patterns termed “resource elements”. Resource elements are used to uniquely describe the processing requirements of the component mix and dynamically match them to the processing capabilities of the machining shop. The virtual cell formation methodology is based on four steps: component requirement analysis and generation of processing alternatives; definition of virtual cell capability boundaries; machine tool selection; and system evaluation. The proposed methodology facilitates the dynamic formation of virtual manufacturing structures by providing accurate assessment of the component processing requirements and their matching with the available capabilities of the existing manufacturing facilities.

As a peer‐to‐peer scalable anonymous communication system, WonGoo is a tradeoff between anonymity and efficiency. Usually, the longer the path, the stronger the anonymity, but at the same time the heavier the overhead. WonGoo lengthens the anonymity path and reduces the overhead, providing strong anonymity and high efficiency with layered encryption and random forwarding. The purpose of this paper is to analyze its performance in detail.

The paper focuses on measure the performance of WonGoo system with probability theory. First, it gives a brief description of the system and evaluate its payload. Then it presents a detailed security analysis of the system.

It is shown that WonGoo can protect against (n − 1) attack and provide variable anonymity, as well as how confident the collaborators can be that their immediate predecessor is in fact the path initiator. The paper measures the anonymity degree provided by WonGoo system based on information entropy and compare it with other anonymity systems.

The paper is helpful for the further development of WonGoo system. In addition, the results presented in this paper will be useful for users to design other anonymity system.

WonGoo is a peer‐to‐peer anonymity system that provides strong anonymity and high efficiency with layered encryption and random forwarding. The paper presents a detailed analysis of its performance with probability theory and measures its anonymity degree with information theory.

The traditional dualism view regards stability and change as opposites and separate, two essential but largely incompatible and mutually exclusive elements in an organization, and it advocates contingency theories to handle the paradox situation; more recent research has adopted the paradoxical lens to highlight both the contradiction and the interdependence between the two elements. This paper aims to address how an organization pursues stability and change simultaneously, i.e., how stability and change contradictorily enable each other to promote the development of an organization.

By adopting a case study on the strategic and structural change of Signcomplex in China, this paper attempts to explore the paradoxical relationship between stability and change, especially their interdependence. Multiple approaches were used during data collection to meet the criteria for trustworthiness, and the data analysis went through a five-step process. Through this analysis, the main mechanisms of stability and change were identified. An analysis was also conducted on how these stable and variable mechanisms enable each other, and finally, a framework was set up to show this paradoxical relationship.

The results confirm the paradox of stability and change: stability enables change by supplying security and consistency, offering reserved knowledge and skills and enabling commitment and the provision of resources for a better realization of the change. Change enables a firm to set up a new state of stability through variable mechanisms such as trial-and-error and exploration activities. The results also indicate that the nature of organizational change is to help an organization reach a new stable stage with higher efficiency and that organizational development relies on the paradoxical effects of both stability and change.

This research is constrained by several limitations. The findings need to be further confirmed through the investigation of more organizations; other stable mechanisms, such as habits, tight coupling, commitments, control and low variance, and variable mechanisms, such as search, mindfulness, redundancy and openness, should be considered. As an organization may experience many cross-level or cross-department changes which struggle with each other for resources and with stable mechanisms, to explore the paradox, future research may need to conduct a more in-depth examination of the system of change.

The findings offer some valuable insights for further research and hold important implications for management practices, especially management practices in a Chinese context. The findings extend the existing paradox theory by further revealing how stability and change enable each other and offer a paradoxical perspective to look into the nature of organizational change and organizational development. The results remind managers to rethink the relationship between stability and change, to factor these coexisting concepts into their decision-making and to accept, understand and use this paradoxical relationship to realize synergistic effects for the firm.

The purpose of this paper is to develop an analytical approach to evaluate the influence of material uncertainties on cross‐sectional stiffness properties of thin walled composite beams.

Fuzzy arithmetic operators are used to modify the thin‐walled beam formulation, which was based on a mixed force and displacement method, and to obtain the uncertainty properties of the beam. The resulting model includes material uncertainties along with the effects of elastic couplings, shell wall thickness, torsion warping and constrained warping. The membership functions of material properties are introduced to model the uncertainties of material properties of composites and are determined based on the stochastic behaviors obtained from experimental studies.

It is observed from the numerical studies that the fuzzy membership function approach results in reliable representation of uncertainty quantification of thin walled composite beams. The propagation of uncertainties is also demonstrated in the estimation of structural responses of composite beams.

This work demonstrates the use of fuzzy approach to incorporate uncertainties in the responses analytically, in turn improving computational efficiency drastically as compared to the Monte‐Carlo method.

MOST modern internal combustion piston engines when under power have such a contented purr that many people contend that no serious lubrication problems of a technical variety remain to be solved, and that the only problems worth mentioning are those which are solely of an economic nature. Such views are, in their own way, flattering to the oil manufacturer who has striven hard, in conjunction with engine manufacturers, to bring these engines to a high pitch of reliability in a relatively short time. However, complacency in a world of change can be a dangerous thing.

Business process models, while primarily intended for process documentation, communication, and improvement, are often also used as input for developing process-oriented software systems (Ouyang et al., 2009). Ensuring correctness, handling complexity, and improving reusability and maintainability of business process models are important for all these goals. The purpose of this paper is to propose an aspect-oriented business process modeling and correctness controlling method based on Petri nets to satisfy these goals.

The aspect-oriented paradigm provides a proper mechanism to modularization, and thus reduces the complexity of models, and also improves reusability and maintainability. However, weaving aspects into base processes may bring in mistakes or errors. To ensure correctness of modeling, this paper presents a formal approach to modeling aspect-oriented business processes and a method to ensure modeling correctness. Petri net is used as the process modeling language and its analysis techniques are applied to analyze the correctness of modeling. Two types of correctness, specifically, aspect-aspect correctness and base-aspect correctness are analyzed. A real banking process model is studied systematically in the case study to evaluate the approach and the performance assessments are conducted to show the cost and effect of the approach.

Designing aspect-oriented business process models help organizations reusing the model elements to reduce redundancy of their model repository, improving their maintainability, and supporting them to adapt to the changes of business requirements with flexible modeling. It is important to stress that the correctness of business process modeling is important in ensuring the quality of the models, especially in the safety-critical business domains, such as financial business domain.

In this paper, separation of concerns is used to separate the cross-cutting activities and core activities in accordance with the different functions of these activities, and an approach to modeling aspect-oriented business processes is proposed. First, the cross-cutting activities are encapsulated as aspects, while core business activities are modeled as base processes. Then, according to the correctness requirements of business process models, based on the weaving mechanisms of aspect-oriented approach, weaving correctness is defined. Weaving correctness controlling methods between multi-aspects and between aspects and base processes are designed. Errors or mistakes of aspect-oriented business process modeling are prevented during the procedure of modeling to ensure error-free business process modeling.

A troublesome tool may represent capital investment standing idle and the toolroom itself, therefore, calls for efficient management if capital expenditure is to be successfully deployed. Production engineers may cast around for means of saving costs but seldom pay attention to the toolroom. Is this because toolmakers are craftsmen and it is implied, therefore, they always work effectively when making tools or repairing old ones? This may be so, but there are many cases in the past, the present and, no doubt, in the future where tools costs are far too high relative to the product involved.

The purpose of this numerical work is to present and test a new approach for large-scale scalar advection (splicing) in large eddy simulations (LES) that use the linear eddy sub-grid mixing model (LEM) called the LES-LEM.

The new splicing strategy is based on an ordered flux of spliced LEM segments. The principle is that low-flux segments have less momentum than high-flux segments and, therefore, are displaced less than high-flux segments. This strategy affects the order of both inflowing and outflowing LEM segments of an LES cell. The new splicing approach is implemented in a pressure-based fluid solver and tested by simulation of passive scalar transport in a co-flowing turbulent rectangular jet, instead of combustion simulation, to perform an isolated investigation of splicing. Comparison of the new splicing with a previous splicing approach is also done.

The simulation results show that the velocity statistics and passive scalar mixing are correctly predicted using the new splicing approach for the LES-LEM. It is argued that modeling of large-scale advection in the LES-LEM via splicing is reasonable, and the new splicing approach potentially captures the physics better than the old approach. The standard LES sub-grid mixing models do not represent turbulent mixing in a proper way because they do not adequately represent molecular diffusion processes and counter gradient effects. Scalar mixing in turbulent flow consists of two different processes, i.e. turbulent mixing that increases the interface between unmixed species and molecular diffusion. It is crucial to model these two processes individually at their respective time scales. The LEM explicitly includes both of these processes and has been used successfully as a sub-grid scalar mixing model (McMurtry et al., 1992; Sone and Menon, 2003). Here, the turbulent mixing capabilities of the LES-LEM with a modified splicing treatment are examined.

The splicing strategy proposed for the LES-LEM is original and has not been investigated before. Also, it is the first LES-LEM implementation using unstructured grids.