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The purpose of this paper is to study the performance metrics of redundant repairable machining system which is applicable in various systems like computer and communication system, manufacturing and production system, etc.

In the present investigation, the authors develop Markov model for the system consisting of identical active operating machines which are prone to breakdown. The operating machines are under the care of one permanent repair facility that provides time-sharing basis repair services. The maintenance is facilitated with the provision of standby machines of mixed type and permanent as well as additional repair facility. From the economic point of view, F-policy and N-policy to control the service and arrival of failed machines effectively are included.

For the performance analysis of the system in long run, the authors compute steady-state probabilities using product-type solution method recursively. Sensitivity analysis is performed numerically for various parameters by developing code in MATLAB.

The performance prediction done may be helpful for the system designers and decision makers for the improvement of the existing machining systems in various industries.

Markovian model for the performance prediction of fault tolerant multi-identical operating and standby machines redundant system is developed in generic frameworks by incorporating many noble features which were not all taken together by other researchers working on the same lines. The key concepts incorporated for the modeling of the concerned system is: F-policy, N-policy, time-sharing, and sensitivity analysis of availability and cost function.

The purpose of this paper is to put forward a nvew reconfigurable multi-mode walking-rolling robot based on the single-loop closed-chain four-bar mechanism, and the robot can be changed to different modes according to the terrain.

Based on the topological analysis, singularity analysis, feasibility analysis, gait analysis and the motion strategy based on motor time-sharing control, the paper theoretically verified that the robot can switch between the four motion modes.

The robot integrates four-bar walking, self-deforming and four-bar and six-bar rolling modes. A series of simulation and prototype experiment results are presented to verify the feasibility of multiple motion modes of the robot.

The work presented in this paper provides a good theoretical basis for further exploration of multiple mode mobile robots. It is an attempt to design the multi-mode mobile robot based on single loop kinematotropic mechanisms. It is also a kind of exploration of the new unknown movement law.

Beijing rail transit can actively control the density of rail transit passenger flow, ensure travel facilities and provide a safe and comfortable riding atmosphere for rail transit passengers during the epidemic. The purpose of this paper is to efficiently monitor the flow of rail passengers, the first method is to regulate the flow of passengers by means of a coordinated connection between the stations of the railway line; the second method is to objectively distribute the inbound traffic quotas between stations to achieve the aim of accurate and reasonable control according to the actual number of people entering the station.

This paper analyzes the rules of rail transit passenger flow and updates the passenger flow prediction model in time according to the characteristics of passenger flow during the epidemic to solve the above-mentioned problems. Big data system analysis restores and refines the time and space distribution of the finely expected passenger flow and the train service plan of each route. Get information on the passenger travel chain from arriving, boarding, transferring, getting off and leaving, as well as the full load rate of each train.

A series of digital flow control models, based on the time and space composition of passengers on trains with congested sections, has been designed and developed to scientifically calculate the number of passengers entering the station and provide an operational basis for operating companies to accurately control flow.

This study can analyze the section where the highest full load occurs, the composition of passengers in this section and when and where passengers board the train, based on the measured train full load rate data. Then, this paper combines the full load rate control index to perform reverse deduction to calculate the inbound volume time-sharing indicators of each station and redistribute the time-sharing indicators for each station according to the actual situation of the inbound volume of each line during the epidemic. Finally, form the specified full load rate index digital time-sharing passenger flow control scheme.

The purpose of this paper is to propose an optimum form of incentive contracts with multiple outcomes and multiple agents.

Utility theory and principal-agent theory provide the underlying basis for this paper. A sample of 60 practitioners from public organizations and private companies participated in an exercise to validate the proposed model.

The paper shows that, in outcome sharing contracts, the contributions of agents toward outcomes are positively related, while agent effort costs, outcome uncertainty, outcome correlation and agent level of risk aversion are negatively related. The paper further demonstrates that outcome sharing is positively associated with the level of effort selected by the agents.

Outcome sharing models might be used in construction contracts to encourage the agent to act in the interests of the principal. However, few studies have looked at contracts with multiple outcomes and multiple agents. This paper contributes to the current practice of contract management through simplifying the complex nature of multiple incentive contracts and providing theoretical guidance for multi arrangements.

The particular value of microcomputer software within the information services of a large research‐based organisation, where ready access to powerful, time‐sharing computer facilities may be available, is discussed. Several reasons for using micro systems are outlined (unique software features, need for specific hardware, means of cheap evaluation, etc.). Examples are given, including expert system shells, spreadsheets, ideas processing software, and database systems.

The last decade has witnessed a growing concern among computer scientists to understand the complex interactions between humans and computer hardware. The work described in this paper is an experimental study of a user‐computer interaction on a time‐sharing computer terminal network over a period of 1 year. The user‐system interaction described in this paper refers to a university environment. The user‐system performance variables considered are arrival patterns of jobs, inter‐arrival time, connect time, cpu time and think time. The users of the systems are grouped into on‐ and off‐campus users; a two‐way analysis of variance without replications established that arrival volume depended upon the weekday but not upon the user group. The pattern of arrivals throughout one day required an empirical distribution. Coefficient of variation indicated hyper‐exponential distributions for inter‐arrival time, connect time and cpu time, but an exponential distribution for think time. Furthermore, the experimental research described in this paper supports the fact that a hypothesis to characterize the interaction between the user and the computing system can be developed for an efficient use of the system.

This study aims to solve the problem of the existing metal foreign object (MFO) detecting systems, which are not sensitive to the small size MFO in wireless charging region of electric vehicle (EV) because of the extremely complex signal noise in the process of wireless charging of EV.

A method for MFO detection based on the principle that MFOs can cause mistuned resonance of detection coil resonant circuit is proposed. The general scheme of detecting system is proposed. The design method for detection coils which is effective to small MFOs detection in large-area region of wireless charging of EV is presented. The design of time-sharing driving circuit and amplifying circuit of high frequency exciting signal for detection coils is introduced. The design scheme of signal processing circuit (including filter and rectifier) of detection coil terminal voltage is also proposed.

The influence of exciting frequency of detection coils on detecting sensitivity and the anti-noise feature of system are analyzed according to the experiment results.

The experiment of MFO detection indicates that the proposed method can effectively detect the coin-sized small MFO in the process of wireless charging of EV.

Over the past decade the development of computer technology and its application to modern‐day business problems has revolutionised the whole process of business control and managment decision‐making. After initially being introduced in the financial and accounting sectors, the use of computers has been expanded to the extent that their impact is felt in nearly every department of the modern business organisation.

The most suitable system architecture for higher education has been dramatically altered by rapid change in information technology and its use. The low cost of mini‐ and microcomputer technology has not only decentralized academic computing, it has made computing a ubiquitous tool for the student, faculty, and staff community across all disciplines. The microcomputer provides access to substantial computing at low cost, and stimulates distributed investment in computing capacity. However, the radical decentralization of computing in the university has also created substantial liabilities, such as increased difficulty in sharing information and resources. The characteristics of a powerful institution‐wide network, which will overcome existing problems with a decentralized environment, are detailed.

The general orientation of services marketing literature with regard to consumer or buyer behavior has been with “at‐need” purchases, those purchases made only when current consumption needs are felt. This standard approach has overlooked purchase behavior that has a time lag to consumption. “Pre‐need” services are purchased in anticipation of their future use. The characteristics of “pre‐need” services are identified and a model or framework is developed for integrating the pre‐need dimension with the marketing mix variables. The model leads to important managerial and research implications in the pre‐need marketing of services.