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The purpose of this paper is to present the direct kinematic analysis of a heavy‐payload forging manipulator. In the grasping stage, the manipulator is equivalent to a 3‐DOF under‐actuated mechanism. In order to deal with the direct position kinematics of the under‐actuated mechanism, the analysis is performed in two steps.

The paper analyzes the direct position kinematics of the 3‐DOF under‐actuated mechanism as follows: first, the authors add a virtual constraint on the mechanism, convert it to a 2‐DOF fully actuated mechanism and calculate the direct kinematics of the constrained mechanism. Then, the constraint is applied to many different positions and the corresponding direct kinematics of the constrained mechanism are calculated, respectively. Finally, the mechanism with lower gravitational potential energy than any other constrained mechanism is chosen, and its direct position is what is needed for the 3‐DOF underactuated mechanism.

The paper provides a solution for the direct kinematic analysis of a heavy‐payload forging manipulator in the grasping stage. Furthermore, the simulation and experiment results confirm the effectiveness of the solution.

The paper proposes a methodology to deal with the direct position kinematics of the 3‐DOF under‐actuated mechanism in two steps.

A consistent implementation of the general computational framework of unified second-order time accurate integrators via the well-known GSSSS framework in conjunction with the traditional Finite Difference Method is presented to improve the numerical simulations of reactive two-phase flows.

In the present paper, the phase interaction evaluation in the present implementation of the reactive two-phase flows has been derived and implemented to preserve the consistency of the correct time level evaluation during the time integration process for solving the two phase flow dynamics with reactions.

Numerical examples, including the classical Sod shock tube problem and a reactive two-phase flow problem, are exploited to validate the proposed time integration framework and families of algorithms consistently to second order in time accuracy; this is in contrast to the traditional practices which only seem to obtain first-order time accuracy because of the inconsistent time level implementation with respect to the interaction of two phases. The comparisons with the traditional implementation and the advantages of the proposed implementation are given in terms of the improved numerical accuracy in time. The proposed approaches provide a correct numerical simulation implementation to the reactive two-phase flows and can obtain better numerical stability and computational features.

The new algorithmic framework and the consistent time level evaluation extended with the GS4 family encompasses a multitude of past and new schemes and offers a general purpose and unified implementation for fluid dynamics.

The purpose of this paper is to investigate Generation Y consumers’ symbolic consumption on brand attitude and purchase intention toward global brands.

A conceptual model has been developed to illustrate the proposed relationships among the related variables. Data from a total of 300 usable surveys were collected from Thai Generation Y consumers. The proposed hypotheses were tested using structural equation modeling analyses.

The study found that Generation Y consumers’ symbolic consumption has a significant and positive effect on brand attitude and purchase intention.

Time and resources limitation did not allow to study the larger sample. Future research should include more product categories and more global brands. Sample can be extended to consumers in ASEAN countries to provide more comprehensive insights into consumer perceptions and brand behaviors toward global brands.

The findings suggest that symbolic consumption is a key motivation to increase purchase intention when developing marketing strategies for the Generation Y consumer.

This study has contributions to symbolic consumption and Generation Y literature combining several important dimensions into a structural model, and examines the relationships among these dimensions.

This study aims to present a numerical study on the flow and heat transfer performance of a water-cooled tube with protrusions in different geometrical parameters.

A new type of enhanced heat exchanger tube is designed. Protrusions are formed on the inner surface of the tube by mechanical expansion, compression and other processing methods. A three-dimensional numerical symmetry model is established by ANSYS for studying the influence of protrusion distance, protrusion radius and protrusion arrangement on flow and heat transfer characteristics in turbulent flow.

The results show that the protrusions increase the heat transfer area and improve the heat transfer effect but also increase the flow resistance. Performance evaluation criteria (PEC) is applied to evaluate the flow and heat transfer characteristics of convex tubes. When adopting the aligned protrusions arrangement, the radius of 2 mm and distance of twice the protrusion radius is most heat transfer effect. The PEC of protrusion tubes with a staggered arrangement are higher than those in aligned arrangement, and the maximum value is 2.36 when Reynolds number is 12,000.

At present, most of the protrusion technology applications are based on the cold plate heat dissipation of electronic devices, and the flow path is rectangular. Convex tube heat exchanger is a high-efficiency heat exchanger, which uses convex tubes instead of smooth tubes in tubular heat exchangers to enhance heat transfer and widely used in petroleum, chemical, textile, oil refining and other industries.