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This paper presents a new method for deploying RoboCrane‐type cable robots, without the need for fixed rigid cable support points. That is, the system provides its own deployable mobile overhead support points.

This paper presents a new RoboCrane support concept based on rigid members, cable actuation, and cable suspension. It is self‐contained and provides mobility for the required six overhead cable connections, thus extending the workspace of the existing RoboCrane. The paper presents the RoboCrane support concept overview, followed by kinematics and statics analysis, plus a case study of a specific design.

Design for kinematic horizontality, workspace, and statics are competing so the designer must make tradeoffs for the best system performance according to specific design needs.

Since the support system plus RoboCrane are both cable‐suspended robots, there are limitations in the pseudostatic workspace, i.e. since the cables can only exert tension and cannot push, the motion range is limited.

Specific system design and deployment is still remaining work – practical issues such as outriggers for moment and tipping resistance, easy portability, control of the mast from the ground, and safety must be solved in the future.

Enables RoboCrane applications in many more arenas, such as automated construction, where rigid overhead cable support points are simply unavailable.

This paper aims to present a kinematics analysis method and statics based control of the continuum robot with mortise and tenon joints to achieve better control performance of the robot.

The kinematics model is derived by the geometric analysis method under the piecewise constant curvature assumption, and the workspace and dexterity of the proposed robot are analyzed to optimize its structure parameters. Moreover, the statics model is established by the principle of virtual work, which is used to analyze the mapping relationship between the bending deformation and the applied forces/torques. To improve the control accuracy of the robot, a model-based controller is put forward.

Results of the experiments verify the feasibility of the proposed continuum structure and the correctness of the established model and the control method. The force deviation between the theoretical value and the actual value is relatively small, and the mean value of the deviation between the driving forces is only 0.46 N, which verify the established statics model and the controller.

The proposed model and motion controller can realize its accurate bending control with a few deviations, which can be used as the reference for the motion planning and dynamic model of the continuum robot.

In this article we design an econometric test for monotone comparative statics (MCS) often found in models with multiple equilibria. Our test exploits the observable implications of the MCS prediction: that the extreme (high and low) conditiona l quantiles of the dependent variable increase monotonically with the explanatory variable. The main contribution of the article is to derive a likelihood-ratio test, which to the best of our knowledge is the first econometric test of MCS proposed in the literature. The test is an asymptotic “chi-bar squared” test for order restrictions on intermediate conditional quantiles. The key features of our approach are: (1) we do not need to estimate the underlying nonparametric model relating the dependent and explanatory variables to the latent disturbances; (2) we make few assumptions on the cardinality, location, or probabilities over equilibria. In particular, one can implement our test without assuming an equilibrium selection rule.

Following Hadar and Seo, the paper aims to determine, in the case of a portfolio with three assets, the condition of preservation of comparative statics results under which a change in risk increases the optimal value of the decision variables for all risk‐averse investors.

Using the first‐ and second‐order conditions, the paper examines a theoretical approach of a particular portfolio problem in two stages. The first step considers the case of dependence between assets where the second extends previous results in the case of dependence between assets.

It is found that even in the case of portfolio with two risky assets and one risk less asset that an FDS or an MPC deterioration that affects either the distribution will increase the weight of this asset in the optimal fund for all decision makers whose preferences exhibit decreasing absolute risk aversion.

The paper extends the previous study in the case of dependence between assets and examines portfolio with more than two assets.

The purpose of this paper is to solve the optimal managerial compensation problem when shareholders are either naïvely optimistic or rational.

The paper uses applied game theory to derive the optimal CEO compensation package with over optimistic shareholders.

The results suggest that boards of directors should decrease option grants to CEOs when equity is likely to be irrationally overvalued at the date when the CEO's options vest.

The implications of the model are consistent with the available empirical evidence. In addition, the model generates new testable predictions about managerial stock price manipulation, the number of options granted, and the magnitude of the options’ strike prices that have not yet been formally tested.

This is the only paper to derive closed-form solutions to optimal CEO compensation when shareholders are naïvely optimistic.

This paper aims to present the model and method involving multi-body system dynamic analysis, finite element quasi-statics contact analysis and numerical calculation of elastohydrodynamic lubrication (EHL), according to the cam wear prediction using Archard’s model. Cam–follower kinematic pairs always work under wear because of concentrated contacts. Given that a cam and follower contact often operates in the mixed or boundary lubrication regime, simulation of cam wear is a multidisciplinary problem including kinematic considerations, dynamic load and stress calculations and elastohydrodynamic film thickness evaluations.

Multi-body system dynamic analysis, finite element quasi-statics contact analysis and numerical calculation of EHL are applied to obtain the dynamic loads, the time histories of contact pressure and the oil film thicknesses in cam–follower conjunctions to predict cam wear quantitatively.

The wear depth of the cam in the valve train of a heavy-load diesel engine is calculated, which is in good agreement with the measured value in the practical test. The results show that the cam–tappet pair operates under a mixed lubrication or boundary lubrication, and the wear depths on both sides of the cam nose are extremely great. The wear of these points can be decreased significantly by modifying the local cam profile to enlarge the radii of curvature.

The main value of this work lies in the model and method involving multi-body system dynamic analysis, finite element quasi-statics contact analysis and numerical calculation of EHL, which can give good prediction for the wear of cam.

The globalization of markets and businesses has meant that many companies now consider the world as a potential marketplace. In this changing environment, two crucial decisions taken by companies are time of entry (e.g. whether to enter early or late) and level of involvement (e.g. whether to adopt low involvement modes such as exports or high involvement modes such as sole venture). Although existing research has examined these issues and underscored the importance of these two decisions in isolated descriptive research, none has developed an integrated mathematical modeling framework for handling these two decisions simultaneously. To alleviate this important gap in the literature, develops a mathematical model for considering these decisions in a simultaneous framework. The results of the model are illustrated by means of numerical simulations. Managerial implications of the model and future research directions are delineated.

Companies are increasingly bringing personnel together into teams from different countries, physically and/or electronically, to develop products for multiple or worldwide markets. Called global new product teams (GNPTs), these groups face significant challenges, including cultural diversity. Differing cultural values can lead to conflict, misunderstanding, and inefficient work styles on the one hand, and strong idea generation and creative problem solving on the other. A study was conducted to identify team compositions that would optimize the effects of national culture so that product development outcomes are favorable. This began by developing a theoretical framework describing the impact of national culture on product development tasks. The framework was then translated into several mathematical models using analytical derivations and comparative statics. The models identify the levels and variances of culture values that maximize product development success by simultaneously considering four relevant dimensions of GNPT performance. Next, the utility of these models was tested by means of numerical simulations for a range of team scenarios. Concludes by drawing implications of the findings for managers and researchers.

The purpose of this paper is to develop and test a theoretical model of managerial decisions involving international market entry.

The authors propose a mathematical model that seeks the optimal level of cultural distance between the host and the home country and the market potential of the host country that maximizes a firm's investment in an international market. The authors illustrate the intuition and the managerial application of the model using a large data set of cross‐border acquisitions, then the results of this data set are used to validate the model in a specific data context.

The authors find that cultural distance and market potential have curvilinear and interaction effects on the level of equity participation. The empirical results are further used to conduct sensitivity analysis of decisions for changes in parameters.

The authors’ general approach can be used to analyze any two variables that have interaction effect on a variable of interest related to market entry strategies.

The authors illustrate the intuition and the managerial application of the model using a large data set of cross‐border acquisitions. Managers can use this approach in choosing CBA targets.

The study provides a mathematical framework and an empirical illustration of optimizing the cultural distance and market potential for maximizing equity participation in foreign market acquisitions. This is a new unique contribution to the literature.