Dynamic responses and control of geared transmission system based on multibody modeling methodology

In this study, an innovative modeling approach is put forward to research the effect of eccentricity on the nonlinear dynamical behaviors of geared-bearing system. This refined model contains the rigid body of the rotor-bearing system and separated gear teeth which are considered as individual bodies elastically attached to the gear hub with revolute joints. The internal and external excitations of the proposed model include torsional joint stiffness, roll bearing forces, friction between gear pair, gear eccentricity, and so on. The systematic procedure for the calculation of torsional joint stiffness, bearing forces and friction coefficient considering elastohydrodynamic is also conducted. After that, the influence of eccentricity on nonlinear dynamic characteristics of the geared transmission system is analyzed. To avoid the system moving in the unstable motion state, a dry friction damper controller is designed to control the nonlinear behaviors simulated on the basis of above model. The linear feedback and periodic excitation non-feedback control strategies are, respectively, selected to design the actuator. It is indicated that undesirable behaviors of the geared transmission system can be avoided effectively by applying the proposed control method.

How can suppliers increase their buyers’ CSR engagement: the role of internal and relational factors

PurposeBuyer engagement proves important supports for suppliers' corporate social responsibility (CSR); however, little is known about whether and how buyer CSR engagement can be actively searched for by a supplier and what activities and policies of suppliers could enhance buyer CSR engagement. From the perspective of resource dependence theory, this study aims to explore how suppliers seek to achieve buyers' CSR engagement.Design/methodology/approachThe proposed model and hypotheses were tested by structural equation modeling methodology using survey data collected from 243 manufacturing and service firms in China.FindingsThe results show that instrumental CSR motives and internalization of CSR policies jointly improve buyers' dependence, which in turn increases buyers' CSR engagement. In addition, this study investigates the influence of suppliers' trust on the effect of buyers' dependence on buyers' CSR engagement and finds a negative moderating effect on the dependence–engagement relation.Practical implicationsThe findings show that suppliers can actively engage in CSR to strengthen their position and improve the buyer CSR engagement. In fact, proactive CSR policies and implementation do pay off in the long run for them.Originality/valueThis study offers a fresh perspective on the role of suppliers in improving CSR. In contrast to much of the literature that has considered buyer-initiated practices and policies, this is the first theoretical and empirical investigation into how suppliers can increase the buyer CSR engagement.

Lean Enhancement by Application of Total Interpretive Structural Modelling

Prioritizing of factors for effective lean manufacturing poses a challenge to management due to complexities in interrelationships. Diligent understanding of measures of lean manufacturing assumes great importance. Essential manufacturing flexibilities take care of uncertainties driven by dynamics of the market. Interrelationship between factors of manufacturing flexibility and lean manufacturing adds to complexity. Judicious analysis of these factors is imperative to understand their effect on lean manufacturing. Total interpretive structural modeling methodology is used for establishing relationships among the factors affecting lean performance. Case studies have been carried out and TISM is applied to understand the dynamism of factors. Study brings out how the organization of the companies and level of automation help in understating the driving and dependence power. The study helps in understanding the influence of hierarchy and level of factors identified by TISM technique on lean performance as also the factors which merit attention of top management to achieve better results

Integrative Model of Strategic Environmental Scanning based on Crises Management Approach

The aim of this study is to examine the way top managers scan environmental conditions to diagnose and interpret issues during periods of crisis. Despite each of these processes being widely and individually represented in the research literature, there is a lack of integrative models that examine their internal dynamics in-depth. In this study, structural equation modeling methodology (EQS 6.3) was applied to a sample of 120 top managers to examine how the cognitive orientation of scanning (rational vs. intuitive analysis of environment) may influence final issue categorizations. The overall findings of the current study show that strategic Environmental Scanning is conducted in UNRWA and has a stoical relation with crises management. This relation is weak and need to be strengthen especially during and after the crisis. The study suggest that strategic Environmental Scanning must be conducted permanently for external and internal environment to help UNRWA developing its strategic planning and to be to prepared to deal with potential crises in the future. Keywords: Strategic Environmental Scanning, Crises Management, UNRWA

Simulation and Optimization of Internal Combustion Engines

Simulation and Optimization of Internal Combustion Engines provides the fundamentals and up-to-date progress in multidimensional simulation and optimization of internal combustion engines. While it is impossible to include all the models in a single book, this book intends to introduce the pioneer and/or the often-used models and the physics behind them providing readers with ready-to-use knowledge. Key issues, useful modeling methodology and techniques, as well as instructive results, are discussed through examples. Readers will understand the fundamentals of these examples and be inspired to explore new ideas and means for better solutions in their studies and work. Topics include combustion basis of IC engines, mathematical descriptions of reactive flow with sprays, engine in-cylinder turbulence, fuel sprays, combustions and pollutant emissions, optimization of direct-injection gasoline engines, and optimization of diesel and alternative fuel engines.

Construction of Concepts Images from Mathematical Models Obtained with the Tracker Software

This work aims to investigate the potential of combining the Mathematical Modeling methodology with the use of the software Tracker with undergraduate students in Mathematics in the reconstruction of physical models for the construction of function concepts. For this, a qualitative and exploratory study of bibliographic and experimental character was carried out, involving field activities. Our results point to a greater understanding in the construction of the models, since the mathematical models can be recreated from the correlation to physical models already validated. We also verified that the Tracker software enables an excellent visual perception of different concept images.

Modeling of Formation of Readiness of Cadets of Military Institutions of the Troops of the National Guard of the Russian Federation for Command Activity

Problem and Aim. The article considers the problem of modeling such a pedagogical phenomenon as the cadet’s readiness for command activity. The military professional experience of the future officer was formalized and the correlation of “readiness” with the traditional competence of the military man was validated. The essential components of the modeling process of the cadet’s readiness for command activity are established, the criteria for the effectiveness of such modeling are determined. The purpose of the article is establish the essential components of the process of modeling the readiness of the cadet for command activity, determine the criteria for the effectiveness of such modeling. Methodology. Research methods: comparative analysis of military-vocational training technologies, highlighting the essential intentions of the cognitive plan in them, followed by designing a criteria base for the effectiveness of using such technologies in the formation of cadets’ readiness for command activities. The article considers the problem of modeling such a pedagogical phenomenon as the cadet’s readiness for command activity. The military professional experience of the future officer was formalized and the correlation of “readiness” with the traditional competence of the military man was validated. The essential components of the modeling process of the cadet’s readiness for command activity are established, the criteria for the effectiveness of such modeling are determined.

Development of information culture of students when teaching equations of mathematical physics in the conditions of informatization of education

Problem and goal. In modern conditions, specialists in various subject areas who have an information culture and are able to solve complex professional problems using modern information and communication technologies are in demand. Currently, specialists in the field of applied mathematics are required, which plays an important role in the development of human civilization. Therefore, in the process of teaching various academic disciplines of applied mathematics at the university, including the discipline Equations of mathematical physics, attention should be paid to the development of students information culture. Methodology. When teaching students the discipline Equations of mathematical physics, it is extremely important that the teacher knows not only the content of teaching this discipline of applied mathematics, but also has practical experience in solving equations of mathematical physics by computer means. Such qualities of the teacher will allow him to successfully conduct training sessions in the conditions of informatization of teaching mentioned discipline. At the same time, it ought to be clearly understood that the use of computer technologies in teaching the discipline Equations of mathematical physics must be correct. The necessity to develop and implement in practice a variety of methodological approaches that allow students to develop an information culture in training sessions on that discipline is obvious. Results. The use of advanced pedagogical technologies in training sessions on the discipline Equations of mathematical physics, where computer technologies are used, will allow students to develop an information culture. Conclusion. Computer technologies that students use in the process of solving educational problems require them to have certain skills and abilities to identify their broad capabilities. Students are aware of the role of computer technologies in conducting applied scientific research, understand the role of computer modeling methodology and computational experiment in studying the world around them.

Changing Design Cognition

<p>Building Information Modeling methodology is the current interest for many didactic programs around the world. May be the Master program can be an opportunity to understand the whole BIM concept in the AEC industry. In the Master BIM in Pisa, Italy we are teaching an approach that is not only “tech”. In the Building Information Modeling methodology, the digital representation receives a new strategic task in the world of construction: reducing the gap between the “res aedificanda” and its simulation via object-oriented graphics. Developing research on this way means to offer new powerful opportunities to re-think the link between “the fact” and “its representation”. There is a strong link between graphics approach and cognitive paradigms in design architecture. If the Building Information Modeling could be an answer for the actual needs of the world of AEC, digital design in BIM becomes the way to think the whole project “as one”. In the BIM graphics environment, the digital drawing changes the sign in ontology. To sum up, we are moving beyond vision to "experience" the design before it is built: we design the constructive ontology according to our experience of the “fabrica”. Modeling the interaction means represent the process through the time.</p>