Search results

This study aims to create a better understanding of how practitioners implement and work Agile while balancing the tensions arising between stability and change.

A grounded theory approach was used to explore what happens in practice when software development teams implement and work Agile. The empirical data consists of twenty semi-structured interviews with practitioners working in fourteen different organizations and in six different Agile roles.

As a result, a substantive theory was presented of continuously balancing between stability and change in Agile teams. In addition, the study also proposes three guidelines that can help organizations about to change their way of working to Agile.

The inherent limitation of a grounded theory study is that a substantial theory can only explain the specific contexts explored in that study. Thus, this study's contribution is a substantial theory that needs to be further developed and improved.

The proposed guidelines can help organizations about to change their way of working to Agile. They can also assist organizations in switching from “doing Agile” to “being Agile”, thus becoming more successful.

The new perspective that this study contributes is the fact that our discovered categories show that several inherent processes are ongoing at the same time in order to balance the need to have both stability and change.

Dynamic advertising, including television and online video ads, demands new theory and tools developed to understand attention to moving stimuli. The purpose of this study is to empirically test the predictions of a new dynamic attention theory, Dynamic Human-Centred Communication Systems Theory, versus the predictions of salience theory.

An eye-tracking study used a sample of consumers to measure visual attention to potential areas of interest (AOIs) in a random selection of unfamiliar video ads. An eye-tracking software feature called intelligent bounding boxes (IBBs) was used to track attention to moving AOIs. AOIs were coded for the presence of static salience variables (size, brightness, colour and clutter) and dynamic attention theory dimensions (imminence, motivational relevance, task relevance and stability).

Static salience variables contributed 90% of explained variance in fixation and 57% in fixation duration. However, the data further supported the three-way interaction uniquely predicted by dynamic attention theory: between imminence (central vs peripheral), relevance (motivational or task relevant vs not) and stability (fleeting vs stable). The findings of this study indicate that viewers treat dynamic stimuli like real life, paying less attention to central, relevant and stable AOIs, which are available across time and space in the environment and so do not need to be memorised.

Despite the limitations of small samples of consumers and video ads, the results of this study demonstrate the potential of two relatively recent innovations, which have received limited emphasis in the marketing literature: dynamic attention theory and IBBs.

This study documents what does and does not attract attention to video advertising. What gets attention according to salience theory (e.g. central location) may not always get attention in dynamic advertising because of the effects of relevance and stability. To better understand how to execute video advertising to direct and retain attention to important AOIs, advertisers and advertising researchers are encouraged to use IBBs.

This study makes two original contributions: to marketing theory, by showing how dynamic attention theory can predict attention to video advertising better than salience theory, and to marketing research, showing the utility of tracking visual attention to moving objects in video advertising with IBBs, which appear underutilised in advertising research.

Unlike conventional aircraft, birds can glide without a vertical tail. The purpose of this paper is to analyse the influence of dihedral angle spanwise distribution on lateral-directional dynamic stability by the simulation, calculation in the development of the bird-inspired aircraft and the flight testing.

The gliding magnificent frigatebird (Fregata magnificens) was selected as the study object. The geometric and mass model of the study object were developed. Stability derivatives and moments of inertia were obtained. The lateral-directional stability was assessed under different spanwise distributions of dihedral angle. A bird-inspired aircraft was developed, and a flight test was carried out to verify the analysed results.

The results show that spanwise distribution changing of dihedral angle has influence on the lateral-directional mode stability. All of the analysed configurations have convergent Dutch roll mode and rolling mode. The key role of dihedral angle changing is to achieve a convergent spiral mode. Flight test results show that the bird-inspired aircraft has a well-convergent Dutch roll mode.

The theory that birds can achieve its lateral-directional stability by changing its dihedral angle spanwise distribution may explain the stability mechanism of gliding birds.

This paper helps to improve the understanding of bird gliding stability mechanism and provides bio-inspired solutions in aircraft designing.

This paper considers supply chain management organizations with the aid of 'chaotic systems theory' developed originally in physics and mathematics. Since innovations in supply chain management are vital for organizational survival 'complex systems theory' may assist in fine-tuning managerial philosophies that provide stability in supply chain management because it is on the boundary of chaos that the greatest innovational creativity occurs. Neither 'management by rigid objectives' (MBO) nor 'management by instruction' (MBI) will be suitable for the information society of the twenty-first century because chaotic social systems will no longer be effectively managed. However, the capacity for self-organization will be derived essentially from how supply chain management members accept a shared set of values or principles for action-'management by values' (MBV). Complex systems theory deals with systems that show complex structures in time or space, often hiding simple deterministic rules. This theory holds that once these rules are found, it is possible to make effective predictions and even to control the apparent complexity. The state of chaos that self-organizes is attributable to the appearance of the 'strange attractor' and provides the ideal basis for creativity and innovation in the twenty-first century. In the self-organized state of chaos, social members are not confined to narrow roles and gradually develop their capacity for differentiation and relationships, growing progressively towards their maximum potential contribution to the efficiency of the organization. In this meaning, values act as organizers of 'attractors' of disorder, which, in the theory of chaos, are systems represented by usually regular geometric configurations that predict the long-term behavior of complex systems. In supply chain management organizations (as in all kinds of social systems) the initial principles end up as the final principles in the long term. An attractor is a model representation of the behavioral results of the system. The attractor is not a force of attraction or a goal-oriented presence in the system; it simply depicts where the system is heading based on its rules of motion. In supply chain management organizations that cultivate or shares values of autonomy, responsibility, independence, innovation, creativity, and proactivity, the risk of short-term chaos is mitigated by external complexities that organizations are currently confronting. The strategy is to alter the supply chain management's surroundings so that they can benefit from management by values (MBV).

This study investigates the extent to which, and in what ways and capacities, the incidence of adverse economic conditions burdening the masses, on the macro-level, increases the propensity for the generation of political instability/violence.

Drawing on data from a cross-section of 25 Sub-Saharan African (SSA) countries for the period 2005–2019, fixed effects (FE) and generalized method of moments (GMM) estimations are used to determine the nature and significance of the independent variable (economic condition), complemented by three control variables, on the dependent WGI-defined variable political stability scored on the basis of a continuum from −2.5 (most unstable) to +2.5 (most stable). For the link between political instability and socioeconomic conditions, the study employs a construct derived from frustration-aggression and relative deprivation theory.

The study links socioeconomic adversity to political instability in the context of SSA. In addition, larger populated countries exhibit a greater propensity to political instability than smaller populated countries. In contrast, foreign direct investment (FDI) appears to have no real effect, positive or negative, on political stability.

Poor living conditions seem to be strongly associated with a high risk of political violence in SSA. To buoy socioeconomic status, poverty alleviation needs be elevated into a key initiative in the decision-making agenda, at all levels of governance, with real targeted strides achieved in terms of enhancement of the standard of living of the masses. In addition, policies that control population need to be inaugurated hand-in-hand with welfare measures and a more equitable balancing of the distribution of resources in the society.

Given the high regional incidence of civil strife and violence, combined with a dearth of research of an empirical nature on political risk in SSA, this study provides a largely ignored and useful context on SSA apart from studies on the incidence of violence that consider the developing countries as a monolithic whole.

This study aims to propose an adaptive fractional-order sliding mode controller to solve the problem of train speed tracking control and position interval control under disturbance environment in moving block system, so as to improve the tracking efficiency and collision avoidance performance.

The mathematical model of information interaction between trains is established based on algebraic graph theory, so that the train can obtain the state information of adjacent trains, and then realize the distributed cooperative control of each train. In the controller design, the sliding mode control and fractional calculus are combined to avoid the discontinuous switching phenomenon, so as to suppress the chattering of sliding mode control, and a parameter adaptive law is constructed to approximate the time-varying operating resistance coefficient.

The simulation results show that compared with proportional integral derivative (PID) control and ordinary sliding mode control, the control accuracy of the proposed algorithm in terms of speed is, respectively, improved by 25% and 75%. The error frequency and fluctuation range of the proposed algorithm are reduced in the position error control, the error value tends to 0, and the operation trend tends to be consistent. Therefore, the control method can improve the control accuracy of the system and prove that it has strong immunity.

The algorithm can reduce the influence of external interference in the actual operating environment, realize efficient and stable tracking of trains, and ensure the safety of train control.

The study aims to deal with three theoretical approaches to answer the research question: Does political reform in rentier States (Kuwait as a model) lead to political stability? The first approach: Following the steps of political reform in rentier States leads eventually to political stability. The second approach: Political stability in rentier States does not necessarily lead to political reform. The third approach: In rentier States, the decisive factor in interpreting the correlation between political reform and political stability requires explaining other intermediary factors.

David Easton’s input-output model: Easton defined the political system as the interactions related to the authoritarian allocation of values in society, that is, the distribution of resources by decisions adopted by individuals, and provided a framework for analysis of the political system in which it sees an integrated circuit of a dynamic nature that starts with inputs and outputs feedback, input and output. Inputs refer to the effects of the environment on the system. Outputs are the effects of the system on the environment, which are the decisions and policies taken by the system to meet the demands. Reverse feedback is the flow of information to the system about the results of its actions, the results of its decisions and policies. Generate new inputs in the form of a demand or support, and the system’s feedback feeds a kind of movement.

It can be said that the future of the rentier state is particularly dangerous in the Arab countries where the problem today is the sharp drop in oil prices, which requires the need to enter into the stage of major transformations and work to bring about fundamental changes and enter into radical constitutional, economic, political and social reforms before turning them from the state rent to countries that lack political stability.

The aim of this research is to present a theoretical study of political reform. The study began to consolidate the concept of political reform, which was and still is the goal of many political and social reform leaders and movements, in addition to being a major topic in political theories. Reform can be carried out by violence and by peaceful change. In any case, reform remains a humanitarian need that cannot be ignored or avoided, because the alternative is worsening and deteriorating political and social conditions.

The Arab Spring revolutions set many challenges for the Arab countries. These countries had to start political reforms. The State of Kuwait was one of the most important rentier countries that, after the Arab Spring revolutions, was concerned with ensuring that individuals and groups exercised their political rights through political participation in decision-making. It guarantees the human existence of society and protects it through the law and its legislation, and grants rights and freedoms and does not oppose it.

Political reforms lead to accommodating the demands of the opposition, increasing the political participation of citizens, activating the political role of women, activating the role of civil society and increasing political mobility.

The importance of the research paper is to emphasize the term rentier state and confirm the importance of reform in rentier countries and the paper asks whether the expansion of political rights, citizenship and participation will lead to stability or instability in these countries.

This study aims to examine the effects of board structures (BS) on the financial performance and stability of banks in Africa.

Using annual data of 366 banks from 26 African countries from 2007 to 2015, the study estimates growths in financial performance using net interest margin and risk-adjusted return on assets; bank stability using z-scores; and BS using board size, board independence and board gender diversity. The system generalized method of moments and ordinary least squares panel-corrected standard error estimation strategies are used to estimate panel regressions.

The study concludes that board independence has a negative and significant relationship with financial stability but has diverse relationships with financial performance. Board size and board gender diversity have insignificant relationships with financial performance and stability.

The study has relevant implications for practitioners, policymakers and the academic community. The findings provide evidence of the extent to which BS have been instituted to influence the financial profitability and stability of banks in Africa.

This study offers robust evidence on the role of BS in the performance and stability of banks; using a multidimensional conceptualization of the performance and stability of banks in 26 countries in Africa.

Different age groups display different shopping patterns in terms of how and where consumers buy products. During times of crisis, such behavioural differences become even more striking yet remain under-researched with respect to elderly consumers. This paper investigates the impact of age on retail-related behavioural changes and behavioural stability of elderly shoppers (in comparison to younger consumers) during a crisis.

The authors surveyed 643 Austrian consumers to assess the impact of perceived threat on behavioural change and the moderating effect of age groups. Based on findings from this survey, they subsequently conducted 51 semi-structured interviews to understand the causes of behavioural change and behavioural stability during a crisis.

Elderly shoppers display more stable shopping behaviour during a crisis compared to younger consumers, which is influenced by perceived threat related to the crisis. Such findings indicate that elderly shoppers reinforce their learnt and embedded shopping patterns. The causes of change and stability in behaviour include environmental and inter-personal factors.

Through the lens of social cognitive theory, protection motivation theory and dual process theory, this research contributes to an improved understanding of changes in shopping behaviour of elderly consumers, its antecedents and consequences during a time of crisis. The authors reveal reasons that lead to behavioural stability, hence the absence of change, in terms of shopping during a crisis. They further outline implications for retailers that might wish to better respond to shopping behaviours of the elderly.

This paper studies the lateral stability regulation of intelligent electric vehicle (EV) based on model predictive control (MPC) algorithm.

Firstly, the bicycle model is adopted in the system modelling process. To improve the accuracy, the lateral stiffness of front and rear tire is estimated using the real-time yaw rate acceleration and lateral acceleration of the vehicle based on the vehicle dynamics. Then the constraint of input and output in the model predictive controller is designed. Soft constraints on the lateral speed of the vehicle are designed to guarantee the solved persistent feasibility and enforce the vehicle’s sideslip angle within a safety range.

The simulation results show that the proposed lateral stability controller based on the MPC algorithm can improve the handling and stability performance of the vehicle under complex working conditions.

The MPC schema and the objective function are established. The integrated active front steering/direct yaw moments control strategy is simultaneously adopted in the model. The vehicle’s sideslip angle is chosen as the constraint and is controlled in stable range. The online estimation of tire stiffness is performed. The vehicle’s lateral acceleration and the yaw rate acceleration are modelled into the two-degree-of-freedom equation to solve the tire cornering stiffness in real time. This can ensure the accuracy of model.