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The electromechanical planetary transmission system has the advantages of high transmission power and fast running speed, which is one of the important development directions in the future. However, during the operation of the electromechanical planetary transmission system, friction and other factors will lead to an increase in gear temperature and thermal deformation, which will affect the transmission performance of the system, and it is of great significance to study the influence of the temperature effect on the nonlinear dynamics of the electromechanical planetary system.

The effects of temperature change, motor speed, time-varying meshing stiffness, meshing damping ratio and error amplitude on the nonlinear dynamic characteristics of electromechanical planetary systems are studied by using bifurcation diagrams, time-domain diagrams, phase diagrams, Poincaré cross-sectional diagrams, spectra, etc.

The results show that when the temperature rise is less than 70 °C, the system will exhibit chaotic motion. When the motor speed is greater than 900r/min, the system enters a chaotic state. The changes in time-varying meshing stiffness, meshing damping ratio, and error amplitude will also make the system exhibit abundant bifurcation characteristics.

Based on the principle of thermal deformation, taking into account the temperature effect and nonlinear parameters, including time-varying meshing stiffness and tooth side clearance as well as comprehensive errors, a dynamic model of the electromechanical planetary gear system was established.

In order to extend the application of the original octagonal Goodman–Smith fatigue limit diagram, which is commonly used for the evaluation of structure fatigue stress in engineering, a modification of it is proposed for the structure made of S355 steel (commonly used in high-speed electric multiple units (EMUs) bogie frame).

The modification is made based on Deutscher Verband für Schweißen und verwandte Verfahren e. V. (DVS) 1612 standard and the γ-P-S-N curve, with consideration of the fatigue evaluation requirements of different survival rates and confidence levels. The verification of the modification is performed for three welded joints and for the comparison with the experimental data.

The results indicate that the design survival rate, the design safety margin and the fatigue stress evaluation of welded joint types are all improved by using the modified diagram.

There are relatively few studies on modifying octagonal Goodman–Smith fatigue limit diagram. In this paper, a modified diagram is proposed and applied in order to ensure the safety and durability of key welded structures of rail vehicles.

Diagrams are ubiquitous in economics and are uncontestably among the most used, if not the most important workhorses of economists, though they come in many forms. This essay examines the different uses of graphs and diagrams in the pioneering work of two Victorian economists, Stanley Jevons and Alfred Marshall. We stress the difference between their use as representations and as visual reasoning tools, a difference that became obscured in the twentieth century with the rise of econometrics.

The purpose of this paper is to conveniently and accurately design partial knitting knitted fabrics based on matrix transformation.

Using mathematical modeling, the pattern diagram block matrix and process design matrix of partial knitting knitted fabrics are established, and the process knitting diagram with parameter information is generated. Based on the establishment of the mathematical model of the process knitting diagram, a loop deformation method based on three-dimensional (3D) coordinate point matrix transformation is proposed.

The matrix transformation method can provide a suitable deformed loop mode for partial knitting knitted fabrics and helps to generate a 3D modeling diagram conveniently.

This paper proposed a method of design and modeling of partial knitting knitted fabric based on matrix transformation. Taking the 3D modeling effect of conventional partial knitting as an example to test the modeling method, the results show that after matrix transformation, the loop model can realize the rapid transformation and calculation of the coordinates of the control point and generate a 3D modeling diagram.

Despite corporate communications having an immense impact on corporate success, there is a lack of dedicated techniques for their management and visualization. A potential strategy is to apply business process management (BPM) approach with business process model and notation (BPMN) modeling techniques.

The goal of this study was to gain empirical insights into the cognitive effectiveness of BPMN-based corporate communications modeling. To this end, experimental research was performed in which subjects tested two modeling notations – standardized BPMN conversation diagrams and a BPMN extension with corporate communications-specific concepts.

Standard conversation diagrams were demonstrated to be more time-efficient for designing and interpreting diagrams. However, the subjects made significantly fewer mistakes when interpreting the diagrams modeled in the BPMN extension. Subjects also evolved positive perceptions toward the proposed extension.

BPMN-based corporate communications modeling may be applied to organizations to depict how formal communications are or should be performed consistently, effectively and transparently by following and integrating with BPM approaches and modeling techniques.

The paper provides empirical insights into the cognitive effectiveness of corporate communications modeling based on BPMN and positions the corresponding models into typical process architecture.

This paper aims to study the efficacy of the business model (BM) diagram in the companies’ integrated reports. Diagrams and graphics are an effective way of communicating the complex processes of a business. However, these diagrams should have complete and appropriate content in a gist for easy understanding.

A study of BM diagrams published in the integrated reports of 65 Indian listed companies was carried out. The contents of these diagrams were compared to the requirement of BM as per the international <IR> framework.

While companies presented the BM diagram, there seemed to be a lack of clarity in the definitions of input, output and outcome capitals. Measurable metrics that give a clear understanding regarding the use and generation of resources were missing. The diagram was presented with some information because it had to be, but the purpose of the BM, which is the core of <IR>, was not conveyed. Also, the diagram did not display value creation or erosion effectively.

To the best of the author’s knowledge, this is one of the first studies on the BM diagram in the <IR> space. It emphasises that the diagram can capture the value-creation aspect of the <IR>. Thus, the BM diagram can be used as an effective and concise communication tool for the users of this report.

The purpose of this study is to develop a method of thermodynamic and kinetic evaluation of corrosion properties of alloys.

Method of estimation of corrosion-electrochemical behaviour of multicomponent alloys is proposed. The method takes into account both thermodynamic and kinetic data and is based on mutual construction of equilibrium and polarization potential – pH diagrams. The usage of the proposed method is illustrated in the example of the structural steel 20KT.

Passivation of steel 20KT is determined by formation of oxide film based on magnetite (Fe₃O₄); silicon, manganese and copper oxides as well as manganese sulphides can be locally included into the inner side of the passivation layer. An experimental potential – pH diagram of steel 20KT is constructed. Interpreting the results of polarization measurements revealed good agreement between equilibrium and polarization potential – pH diagrams.

It is shown in the example of structural steel 20KT that for interpretation of experimental potential – pH diagrams, one should compare them with corresponding equilibrium diagrams for multicomponent alloys rather than with Pourbaix diagrams for pure metals. The corrosion properties of steel 20KT are estimated using equilibrium and polarization potential – pH diagrams.

The purpose of this paper is to demonstrate the application of UML extensions on the elicitation of the knowledge that is intrinsic to the business processes of electronic government that will be available on digital TV.

Based on the understanding that: knowledge of e‐government is inherent in the applications available to the citizen; these applications aggregate content and services; and business processes result in products or services that are available for the citizen, this study seeks to, through the use of diagrams proposed by Eriksson and Penker, elicit the knowledge intrinsic to business processes, facilitating the development of applications destined to digital TV.

The proposed model facilitates the understanding of business processes and the identification of opportunities for improvement. The application of the BP diagram has enabled the authors to obtain an overview of all elements participating in the process as well as detail the relationship between them in a single diagram to facilitate the understanding of the process as a whole and assist its implementation. The assembly line diagram not only highlighted the interaction between business processes and information objects read and written in the assembly line, but also aided the identification of use cases that support the actors of the system and, consequently, the preparation of the t‐Government application requirements. The activity diagram provided highlights of how the activities that comprise the processes interact among each other and what flow of action is necessary to achieve the goal of the business process.

It is worth mentioning that what is being dealt with here is t‐Government applications accessible via iDTV (a fixed device). It is also understood that such applications are not tied to a specific TV program, since they are treated as resident applications; that is, citizens download them from an STB TV Channel and can interact with them whenever they want, regardless of the program that is being aired at the moment.

The use of unified modeling language (UML) extensions as a technique for knowledge modeling is a domain still little explored in literature. Although UML was originally designed to assist in systems modeling, its application has been extended to business and knowledge modeling.

Aims to investigate the effect of chlorine on corrosion behaviours of stainless steels.

Very complicated thermodynamic calculations are needed to establish the E‐pH diagrams of commercial alloys, because they comprise of many elements. To avoid these complex calculations and facilitate corrosion prevention of AISI 316L stainless steel, the potentiodynamic method was used to construct the E‐pH diagram. The polarization curves were carefully experimented at the scan rate of 0.1 mV/s. The experimental conditions were aqueous solutions saturated with air (oxygen concentration 7.8‐8.5 ppm) containing chloride 0, 50, 500 and 5,000 ppm, pH 2, 4, 6, 8, 10 and 12, and at 25°C. The transpassive or pitting potential, the protection potential, the primary passive potential and the corrosion potential were determined from the polarization curves and plotted with respect to the pH of the solution. The ions in solution were investigated by qualitative chemical analysis and stated in the E‐pH diagrams.

The constructed E‐pH diagrams showed clearly the effect of chloride concentration in the tested conditions on the transpassive or pitting potential, the protection potential of AISI 316L stainless steels. The ion states after pitting corrosion were different at low and high pH. This may be useful information for further investigation of pitting corrosion mechanisms.

The E‐pH diagram was originally based on thermodynamic equilibrium. The potentiodynamic method was kinetically controlled and not in equilibrium. However, the experiments were kept at near stationary state as much as possible. The investigated E‐pH diagrams were limited for the solutions saturated with air containing chloride 0, 50, 500 and 5,000 ppm and at 25°C. The effects of temperature and other ions such as Fe³⁺, Mg²⁺, Ca²⁺, etc. on the transpassive or pitting potential, the protection potential, the primary passive potential and the corrosion potential should be further investigated, because natural water may contain those ions and is at high temperatures which could affect on the corrosion of AISI 316L stainless steels.

The investigated E‐pH diagrams may be applicable to avoid corrosion of AISI 316L stainless steels in similar conditions. The useful application may be for fields where natural water is not able to be treated, as is carried out in industry.

There have been several investigations on the effect of chloride on the corrosion behaviours of AISI 316L stainless steels. However, those investigations were carried out in different conditions. Very few experimental E‐pH diagrams of AISI 304L have been found, but not for AISI 316L stainless steels. The investigated diagrams showed also the ion states in pitting corrosion region which were influenced by pH. This may indicate the different pitting corrosion mechanism at different pH.

The purpose of the paper is to obtain insight into, and provide practical advice for, event‐based conceptual modeling.

The paper analyzes a set of event concepts and uses the results to formulate a conceptual event model that is used to identify guidelines for creation of dynamic process models and static information models.

The paper characterizes events as short‐duration processes that have participants, consequences, and properties, and that may be modeled in terms of information structures. The conceptual event model is used to characterize a variety of event concepts and it is used to illustrate how events can be used to integrate dynamic modeling of processes and static modeling of information structures.

The results are unique in the sense that no other general event concept has been used to unify a similar broad variety of seemingly incompatible event concepts. The general event concept can be used to improve dynamic and static modeling.