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The finite element method has been increasingly applied in stress, thermal and dynamic analysis of gear transmissions. Preparing the models with different design and modification parameters for the finite element analysis is a time-consuming and highly skilled burden.

To simplify the preprocessing work of the analysis, a parametric finite element modeling method for spur and helical gears including profile and lead modification is developed. The information about the nodes and elements is obtained and exported into the finite element software to generate the finite element model of the gear automatically.

By using the three-dimensional finite element tooth contact analysis method, the effects of tooth modifications on the transmission error and contact stress of spur and helical gears are presented.

The results demonstrate that the proposed method is useful for verifying the modification parameters of spur and helical gears in the case of deformations and misalignments.

This paper aims to present an analytical approach for the determination of helical gear tooth geometry and introduces the necessary parameters. Tooth geometry including tooth chamfer, involute curve, root fillet, helix as well as tooth microgeometry can be obtained using the presented approach.

The presented analytical approach involves deriving the equivalent equations at the transverse plane rather than the normal plane. Moreover, numerical evaluation of microgeometry modifications is presented for tooth profile, tooth lead and flank twist.

An analytical approach is presented and equations are derived and explained in detail for helical gear tooth geometry calculation, including tooth microgeometry. Method 1, which was presented by Lopez and Wheway (1986) for obtaining the root fillet, is examined and it is proven that it does not work accurately for helical gears, but rather it works perfectly in the case of spur gears. Changing the normal plane parameters in Method 1 to the transverse plane ones does not give correct results. Two alternative methods, namely, Methods 2 and 3, are developed in the current research for the calculation of the tooth root fillet of helical gears. The presented methods and also the numerical evaluation presented for microgeometry modification are examined against the geometry obtained from Windows LDP software. The results show very good agreement, and it is feasible to apply the approach using the presented equations.

In the gear design process, it is important to model the correct gear tooth geometry and deliver all related dimensions and calculations accurately. However, the determination of helical gear tooth geometry has not been presented adequately by equations to facilitate gear modelling. The detailed helical gear tooth root has been enveloped using software tools that can simulate the cutter motion. Deriving those equations, presented in this article, provides gear design engineers and researchers with the possibility to model helical gears and perform design calculations in a structured, applicable and accurate method.

This paper aims to achieve an optimum flow separation control over the airfoil using a passive flow control method by introducing a bio-inspired nose near the leading edge of the National Advisory Committee for Aeronautics (NACA) 4 and 6 series airfoil. In addition, to find the optimised leading edge nose design for NACA 4 and 6 series airfoils for flow separation control.

Different bio-inspired noses that are inspired by the cetacean species have been analysed for different NACA 4 and 6 series airfoils. Bio-inspired nose with different nose length, nose depth and nose circle diameter have been analysed on airfoils with different thicknesses, camber and camber locations to understand the aerodynamic flow properties such as vortex formation, flow separation, aerodynamic efficiency and moment.

The porpoise nose design that has a leading edge with depth = 2.25% of chord, length = 0.75% of chord and nose diameter = 2% of chord, delays the flow separation and improves the aerodynamic efficiency. Average increments of 5.5% to 6° in the lift values and decrements in parasitic drag (without affecting the pitching moment) for all the NACA 4 and 6 series airfoils were observed irrespective of airfoil geometry such as different thicknesses, camber and camber location.

The two-dimensional computational analysis is done for different NACA 4 and 6 series airfoils at low subsonic speed.

This design improves aerodynamic performance and increases the structural strength of the aircraft wing compared to other conventional high lift devices and flow control devices. This universal leading edge flow control device can be adapted to aircraft wings incorporated with any NACA 4 and 6 series airfoil.

The results would be of significant interest in the fields of aircraft design and wind turbine design, lowering the cost of energy and air travel for social benefits.

Different bio-inspired nose designs that are inspired by the cetacean species have been analysed for NACA 4 and 6 series airfoils and universal optimum nose design (porpoise airfoil) is found for NACA 4 and 6 series airfoils.

Tourist regions with long tradition and years of experience often have a hard time implementing strategic management concepts. This is due to decision‐making and management processes at the level of tourism policy and the different levels of the tourism organization. These levels were bogged down for many years and aggravated the task of carrying out the required modifications. With the example of the Alpine region South Tyrol, this paper explains the errors that are likely to happen in the formulation and implementation of strategic concepts. The idea was to use a concrete example to explain the interdependence of the individual elements of strategic management from vision to implementation while, at the same time, elucidating the barriers and the sources of resistance to change at tourism organizations.

In September 1976 an article was published entitled ‘Technician Training in the Smaller Firm’. This described the development at SATRA of an in‐company training package for pattern cutters, a technician‐type job in the footwear manufacturing industry. A number of techniques are employed, but the package involves extensive use of guided discovery learning, with the trainee's supervisor taking the role of the major resource of knowledge and expertise. Since the publication, we have received a few comments along the lines that ours is a retrograde step to the days of ‘sitting by Nellie’ and discovery learning is used because the knowledge and skills have not been properly analysed. These raise some interesting points which we feel should be discussed. In particular we would take the opportunity to clarify some of the ideas and thinking behind the training strategies involved in the training programme outlined in the previously mentioned article.

The purpose of this study is to determine whether the implementation of a performance management system comprising some traditional management practices (management process and organizational behavior modification) lead to an ethical organizational environment and improved employee performance.

A structural model is theorized and assessed using data from samples of full-time employees in the USA and Brazil. Partial least squares–structural equation modeling is used.

The findings of this study suggest that management process and organizational behavior modification directly and positively impact the ethical environment, and the ethical environment directly and positively impacts employee performance. The management process and organizational behavior modification indirectly impact employee performance through an ethical environment.

Although this theorized model was tested and provided significant results for implementing the management practices suggested, it is strongly recommended that other random data samples be used to analyze the theorized model and assess to reconfirm the results. In addition, incorporating the ethical environment construct within a larger model that includes other potential antecedents, such as management principles, and other potential outcomes, such as organizational commitment, job satisfaction and workplace optimism, is recommended.

This study provides management practitioners with empirical evidence that implementing a performance management system consisting of the management process and organizational behavior modification will enhance both the ethical environment and organizational trust, which, in turn, will lead to improved individual employee performance. Based on the theoretically and statistically supported framework, managers can improve the performance of their subordinates. The results further support the assertions that managers must implement the management process along with organizational behavior modifications to improve employee performance through an ethical environment and organizational trust

The general conclusion from this study is that good management practices in the form of the management process and organizational behavior modification are inherently ethical. Furthermore, when implemented and consistently maintained by managers, these practices will result in an organizational environment that supports ethical behavior and engenders a high level of trust. The results of this study demonstrate a significant contribution to the existing literature, in that good management is tied, in fact, directly to ethics and trust.

The results provide evidence that good management in the form of the management process and organizational behavior modification yields both a positive ethical environment and improved employee performance. Practitioners are provided with evidence that reaffirms the need to define expectations for employees and to provide the necessary resources and positive reinforcement to fulfill the expectations. This study is one of the first to directly assess the impact of traditional management practices on an ethical environment.

Existing theories of innovation posit a split between incremental innovations produced by large incumbents and radical innovations produced by entrepreneurial start‐ups. The purpose of this paper is to present empirical evidence challenging this foundational assumption by demonstrating that entrepreneurs play a leading role, not a subordinate role, in sourcing incremental innovations through secondary inventions and design modifications.

Applying the methods of historical econometrics, this study draws parallels between two dramatically different contexts: the mechanized reaper (1803‐1884) and cloud computing services (1961‐2011). Data for the reaper were drawn from 517 historical sources involving 348 modifications. Data for cloud computing services were drawn from 3,882 US patent filings and firm‐level data drawn from the Dun & Bradstreet database.

Entrepreneurial tweaking plays a central role in commercializing dominant designs. Among the highest‐ranked incremental innovations leading to the commercialization of the reaper and cloud computing, nearly 90 percent were attributable to entrepreneurs. And yet, an entrepreneur had only a one in fourteen chance of garnering returns from a reaper innovation and a one in nine chance of gains from a cloud computing improvement.

Incremental innovations by entrepreneurs are indispensable to the widespread commercial acceptance of new technologies. Yet, entrepreneurial tweakers rarely benefit from the significant value they have created.

This paper constitutes the first significant attempt to empirically address the central role of entrepreneurs in producing incremental innovations that result in the commercialization of radical breakthroughs.

Using a simulated employment negotiation, this experiment examined the relationship between dyad composition, negotiation strategies and levels of joint gain. Three dyad types were created on the basis of social value orientation, proself, prosocial and mixed. A log linear analysis showed that dyads were differentiated on the basis of the strategies associated with high joint gain. We identified a generic path to high joint gain in which all dyads increased priority information and decreased contention. Overlaid on this path, we identified dyad‐specific strategies and strategy sequences associated with high joint gain. Cooperative reciprocity was critical to high joint gain only in prosocial dyads. When dyads contained at least one prosocial negotiator, process management played an important role in determining the level of joint gain. When dyads contained at least one proself negotiator, the sequences associated with high joint gain functioned to divide resources.

Presents recent advances obtained by the authors in the development of enhanced strain finite elements for finite deformation problems. Discusses two options, both involving simple modifications of the original enhancement strategy of the deformation gradient as proposed in previous works. The first new strategy is based on a full symmetrization of the original enhanced interpolation fields; the second involves only the transposed part of these fields. Both modifications lead to a significant improvement of the performance in problems involving high compressive stresses, showing in particular a mode‐free response, while maintaining a simple and efficient (strain driven) numerical implementation. Demonstrates these properties with a number of numerical benchmark simulations, including a complete modal analysis of the elements.

The purpose of this paper is to attempt to achieve customization while maintaining quick delivery to customers by use of a hybrid of make-to-order (MTO) and make-to-stock (MTS) strategies.

The paper reports on various studies based on simulation, optimization, and Markov analysis to respond to some of the unique challenges of the hybrid strategy.

Implementation of the make-to-forecast (MTF) hybrid strategy provides considerable competitive advantage in certain manufacturing situations by achieving as much as 50 percent shorter delivery times for highly customized products than would be possible with a pure MTO strategy. It also has potential to offer competitive advantages to pure MTS and MTO operations.

The manufacturing situations, appropriate for MTF paradigm, are fairly complex. The paper reviews only several of the many managerial challenges. For instance, it assumes a given product variety but does not dwell on what the optimum product variety offering should be. Additional research to this and other aspects of the situation is warranted.

The paper reports on a real managerial problem. The suggested approaches can be easily implemented by certain manufacturing companies striving to achieve competitive advantage by offering shorter delivery time and substantial customization to their customers.

Managing the trade-off between delivery time and degree of customization is not new. Assemble-to-order, mass customization, and postponement strategies have been suggested to soften the trade-off. This paper provides a new paradigm for the same challenge based on pre-release of units into the manufacturing system in anticipation of customer orders.