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We investigate product innovation by a cohort of entrants who use technology that eventually suffers disruption. We concentrate on two types of entrants – those with and those without relevant prior experience in the disrupted technology. Using the industrial robotics industry as the context of our study, we explore product innovation using disrupted technology during two time periods: the first prior to sales takeoff of the disruptive products and the second subsequent to takeoff. We find that the two types of entrants did not differ in product innovation prior to takeoff, but firms with prior experience in the disrupted technology manufactured more innovative products subsequent to the sales takeoff of disruptive products. Our research underscores that the boundary conditions of the utility of prior experience is more nuanced than that which literature suggests – it affects product innovation only in the post-sales takeoff period when the demand uncertainties are relatively low. Our findings also suggest that the boundary conditions of Christensen’s thesis are narrower than predicted by prior literature.

The paper aims to establish a comprehensive optimization analysis model for a helicopter roll on the ground and take off based on optimal control method. The trajectory and control of the entire process are studied, and the key factors affecting the helicopter takeoff distance are analyzed.

First, based on the equivalent stiffness and damping, the landing gear model is established, and a six-degree-of-freedom helicopter model is formed. Then, the simulation of the roll-on takeoff is transformed into a nonlinear optimal control problem (NOCP). Meanwhile, a hybrid single-multiple shooting method-based transcription process is used for discretizing the problem, leading to a finite nonlinear programming model, which is solved by sequential quadratic programming. Finally, the process was calculated and compared with flight test data, which verified the feasibility of the NOCP. The influence of takeoff weight, takeoff power and liftoff airspeed on the takeoff distance of the helicopter was analyzed.

The results show that the takeoff weight can be increased by 17% under the maximum takeoff power, which is roll-on takeoff at an altitude of 0 m. When the helicopter takes off with the maximum weight at an altitude of 5000 m, the liftoff airspeed should be over 49.2 km/h.

The novelty of this paper lies in the comprehensive consideration of helicopter taxiing and taking-off phases, and the application of optimal control theory to establish a comprehensive analysis model, which can quickly analyze the maximum takeoff weight, takeoff distance, optimal liftoff speed and so on. Meanwhile, the method is verified based on the flight data.

Quantity Takeoff (QTO) is an integral part of the decision-making process. Currently, QTO is mostly done using manual or 2D method, and practitioners are considering the use of BIM quantity takeoff as an effective alternative to the traditional 2D software takeoff. However, the existing literature does not have adequate studies to confirm that the use of BIM-based QTO is better than the 2D method. Therefore, this paper aims to expand and improve the existing literature into a more detailed analysis of each element to investigate that BIM is indeed a better option of the two QTO methods.

A total of 19 factors in four broad categories, i.e. timely decision making, accuracy, collaboration, and level of details were identified to draw a significant comparison between the two procedures, i.e. BIM-based quantity takeoff and traditional 2D takeoff. Surveys and case study are used to collect data for analysis to achieve the research goals.

The questionnaire survey showed that using BIM for the QTO process has significant benefits in achieving higher productivity on takeoff, accuracy, clarity and collaboration among the team members. The case study results also showed improvement in BIM-based QTO by achieving higher accuracy and productivity.

Understanding the difference between the two QTO processes is a challenging task; therefore, this paper contributes to drawing a comparison line between the two processes by introducing the factors that affect the QTO process.

The purpose of this paper is to develop a directional and roll control system for unmanned combat air vehicle (UCAV) automatic takeoff roll, with the objective of keeping the UCAV along the runway centerline and keeping the wings level, especially when there is a crosswind.

The nonlinear model of the UCAV during takeoff roll is established. The model is linearized about the lateral‐directional equilibrium point at different forward speeds. The approximate directional model and roll model are extracted using time‐scale decomposition technique. Then the directional control law and roll control law are developed using gain scheduling approach. Nose wheel steering, differential brake and rudder are used as the primary directional control device at low, medium and high speeds, respectively, according to both the qualitative and quantitative analysis of their control effectiveness at different speeds. A priority matrix is developed to determine the secondary control device which is used if the primary control device fails, thus the directional control system can have a certain degree of fault tolerance.

This work developed the directional control law and roll control law by using gain scheduling approach. Experimental results verified that the developed directional and roll control system has high robustness and satisfactory fault tolerance: it can guarantee a safe takeoff under a 50 ft/sec crosswind, even if one directional control device fails, which satisfies the relevant criteria in MIL‐HDBK‐1797.

The directional and roll control system developed can be easily applied to practice and can steer the UCAV during takeoff roll safely, which will considerably increase the autonomy of the UCAV.

The paper shows how time‐scale decomposition technique is employed to extract the approximate directional model and roll model, which simplifies model analysis and control law design. A fault‐tolerant directional control system is designed to improve safety during takeoff.

The purpose of this paper is to explore how the number and quality of games that publishers have released, popularity of game genre, age rating and package size are configured to determine the mobile game takeoff in a short time.

Based on the signaling theory, the authors present a conceptual model. Using actual data about 170 mobile games at their initial stage in the Apple App store, the authors test the conceptual model by applying fuzzy qualitative comparative analysis (fsQCA).

The findings identify four solutions that explain Mobile game takeoff in a short time. The authors highlight the role of the number and quality of games released by publishers, as well as that of popular game genres, which are always core factors when present.

This paper complements the previous research on the diffusion of mobile games by exploring which information combinations can lead to mobile games takeoff in a short time from the perspective of configuration. FsQCA serves as a better tool for explaining the complex relationships among variables than a regression analysis approach does. The authors extend existing knowledge on how the number and quality of games that publishers have released, popularity of game genre, age rating and package size combine to lead to takeoff of mobile games in a short time.

The purpose of this paper is to focus on the influence of national cultural dimensions on the evolution of national innovation adoption over time. The paper considers the moderating effects of national wealth, population density and illiteracy rate on the role of cultural dimensions in the timing of innovation takeoff in national markets.

The empirical study investigates 137 national innovation adoption time series; the dependent variable being the time it takes for innovation adoption to take off. The independent variables are Hofstede's five cultural dimensions and the moderating variables are gross domestic product (GDP), population density and illiteracy rate.

The outcome of the study shows that cultural dimensions have a greater influence on takeoff time in countries with highly developed economies, dense populations and low illiteracy rates. The study also shows that especially the cultural dimension of individualism has a significant context independent influence on takeoff dynamics, whereas masculinity has no such effect.

The paper provides evidence that the influence of cultural dimensions may be more complex than previously believed. Contribution of the research to the academic community especially lies in results regarding moderation effect of GDP, population density and illiteracy. Other independent and moderating variables could provide useful subjects for further research.

The results of this study could assist companies conducting business in cross‐national settings in planning their international operations in such areas as designing marketing promotions and deciding the entry order into national markets. Especially, useful the results are in pre‐takeoff phase of the evolution of innovation adoption.

The paper extends our understanding of the relationship between the national cultural dimensions and the early evolution of innovation adoption. Incomplete understanding of the cross‐national dynamics of the innovation adoption takeoff is scrutinized and the findings support earlier research that cultural dimensions affect adoption dynamics. The study demonstrates that the influence of cultural dimensions may be dependent on and moderated by other national attributes.

To improve the standards for determining the accelerate‐stop and landing performance of transport aircraft the FAA has published a proposed rule that makes three amendments which are detailed here. The first revises the method for taking into account the time needed for the pilot to accomplish the procedures for a rejected takeoff, another requires that takeoff performance be determined for wet runways, and the third requires that rejected takeoff and landing distances be based on worn brakes. These amendments are based on a notice of proposed rulemaking (NPRM) issued early in the 1990s. These standards are not being applied retroactively either to aircraft currently in use or to aircraft of existing approved designs that will be manufactured in the future.

The purpose of this study is to examine the diffusion pattern of new products in Latin America, and to compare the results of principal component analysis with other descriptive approaches.

The author studies the introduction of eight new products in nine Latin American countries, analysing their diffusion rate, market potential, adoption and take-off. He performs a principal component analysis and presents a biplot. The results obtained are compared using the Mantel test.

The results indicate that the approaches used are complementary. The biplot describes 92 per cent of the explained variance. Except for a few cases, in general, the diffusion pattern in Latin America is mainly determined by cross-country wealth differences.

This study only analyses durable goods, and does not include any Central American country.

This study helps companies to predict which will be the characteristics of the diffusion pattern of other new products and to forecast their future sales.

This study helps public actors to decide how to segment the Latin American market when implementing policies that encourage the diffusion of new products.

This research extends our current knowledge on the diffusion of innovations in emerging and less developed countries. This is the first study to compare the characteristics of innovation diffusion patterns in Latin America.

El propósito de este estudio es examinar el patrón de difusión de nuevos productos en Latinoamérica, y comparar los resultados obtenidos del análisis de componentes principales con otros métodos descriptivos.

Se analiza la introducción de ocho productos nuevos en nueve países latinoamericanos. Se analizan la tasa de difusión, mercado potencial, adopción y el tiempo de despegue. Se realiza un análisis de componentes principales y se presenta en un biplot. Los resultados obtenidos se comparan a través del test de Mantel.

Los resultados indican que los enfoques usados son complementarios. El biplot describe el 92% de la varianza explicada. El patrón de difusión en Latinoamérica está principalmente determinado por la diferencia entre la riqueza de los países. Sin embargo, en algunos casos el patrón de difusión no sigue esta tendencia.

Este estudio solo analiza productos duraderos y no incluye ningún país de Centro América.

Este estudio ayuda a las empresas a predecir cuáles serán las características del patrón de difusión de otros productos nuevos y pronosticar sus futuras ventas.

Este estudio ayuda a actores públicos a decidir sobre cómo segmentar el mercado Latinoamericano a la hora de aplicar políticas que incentiven la difusión de nuevos productos.

Esta investigación avanza en el conocimiento actual sobre la difusión de innovaciones en países emergentes y menos desarrollados. Es el primer estudio que compara las características del patrón de difusión de innovaciones en Latinoamérica.