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An off‐line optimization method is described which allows the determination of “optimal” control strategies in a behavioural systems analysis. The method is based on the theory of learning systems, using a phenomenalistic model of the behavioural process for control experiments. There are no restrictions concerning the degree or order of this model. An outline of an investigation in social psychology demonstrates an application of the proposed method. The analysed data are the same as those used in a report on “System identification in behavioural science” previously published in this journal. This allows comparison of two different approaches to behavioural systems analysis by means of a phenomenalistic model.

The aim of this paper is to undertake analysis and comparison of the closed‐loop and sensorless control systems sensitivity to the broken rotor for diagnostic purposes. For the same vector control system induction motor drive analysis concerning operation with the asymmetric motor, broken rotor fault handling and operation were investigated. Reliability, range of stable operation, fault symptoms and application of diagnosis methods based on control system variables utilization was analyzed.

Induction motor drive vector control system synthesis was applied using the multiscalar variables of the machine model with nonlinear feedback linearization applied to use classical cascaded PI controllers for the speed‐torque and flux decoupled control. Speed observer was applied for the rotor flux and rotor speed estimation for the sensorless control system synthesis.

Relative sensitivity of the state and control system variables to broken rotor fault based on experimental results for the closed‐loop and sensorless control systems is presented and compared. Drawbacks of using the MCSA analysis for the rotor fault diagnosis in the closed‐loop and sensorless control systems are pointed. Advantages and drawbacks of the state space estimators filtering characteristics in the sensorless control system are described.

Asymmetric IM motor drive handling and diagnosis. Broken rotor range diagnosis inconsistency using the popular MCSA method should be considered in the closed‐loop and sensorless control system of the induction motor drive. Depending on the IM motor drive application and the operation requirements the results can be used for asymmetric machine proper handling, choosing proper control system structure and control system variables for rotor fault early diagnosis.

Sensitivity of the state and control system variables to broken rotor fault based on experimental results for the closed‐loop and sensorless control systems is presented, which implies motor handling procedures and fault diagnosis.

The purpose of this paper is analysis of the sensorless control system of induction machine with broken rotor for diagnostic purposes. Increasing popularity of sensorless controlled variable speed drives requires research in area of reliability, range of stable operation, fault symptoms and application of diagnosis methods.

T transformation used for conversion of instantaneous rotor currents electrical circuit representation to space vector components is investigated to apply with closed‐loop modeling algorithm. Evaluation of the algorithm is based on analysis of asymmetry influence to the orthogonal and zero components of space vector representation. Multiscalar model of the machine and selected structures of state observers are used for sensorless control system synthesis. Proposed method of frequency characteristics calculation is used for state observers analysis in open‐loop operation.

New algorithm of applying the T transformation allows for closed‐loop and sensorless control system simulation with asymmetric machine due to broken rotor. Compensating effect of the closed‐loop control system with speed measurements and diagnosis information in control system variables are identified. Proposed frequency analysis of state observers is presented and applied. Variables with amplified characteristic frequency components related to rotor asymmetry are compared for selected structures of state observers and with closed‐loop and open‐loop operation. Method of improving the sensorless system stability is proposed.

In closed‐loop and sensorless control system rotor fault can be diagnosed by using PI output controllers variables. Compensating effect of mechanical variables sets limitation to specified diagnosis methods. Rotor asymmetry affects sensorless control system stability depending on estimator structure.

This paper concentrates upon sensorless control system operation with machine asymmetry and indicates rotor fault symptoms.

This study aims to optionally-piloted aircraft is useful for in-flight tests of new automatic controller’s concepts. The safety of this kind of experiment is an issue addressed in this paper. The prediction of possible safety-influencing factors makes it possible to assess the pilot’s ability to effectively prevent safety risks.

The analysis in this research paper focusses on two cases of monitoring; similar control standards for both pilot in command and the monitoring pilot or technical systems in one of these tasks and dissimilar control standard when monitoring pilot is not familiar with a control manner of the pilot in command or of the automatic control system. The increased workload is expected in the last case as the result of additional activities determined theoretically in the presented analysis. Details of the possible threats are obtained by simulation tests with various factors influencing the safety of landing. In addition to determining threats, the analysis includes the possibility of in time threat detection and preserving action.

The results show that the safety pilot has a different task than the pilot in command and needs to be familiar with the general principles of automatic controller operations and the particular algorithm being tested. Although commonly used landing procedure is relatively error-tolerant, new landing procedures for use in some specific conditions need more precise control and additional safety pilot preparation. Additional information presented to both the pilot in command and the safety pilot may increase mode and state awareness and reduce reaction time in an emergency condition.

In-flight tests of non-standard control algorithms there is a need to include additional preparation of the equipment and safety pilot. The research in this paper illustrates how to determine threats and safety-critical moments during the experimental flight can be observed. The danger is mitigated by the safety pilot, if familiar with both proper and improper operations of the controller and how the pilot in command should detect and predict danger caused by the tested control system.

The presented method of analysis combines the human factor with various technical aspects. The results obtained illustrate the real tasks of the person supervising the operation of the automatic control system and the role of a human as a safety pilot.

Although it is widely acknowledged that health care delivery systems are complex adaptive systems, there are gaps in understanding the application of systems engineering approaches to systems analysis and redesign in the health care domain. Commonly employed methods, such as statistical analysis of risk factors and outcomes, are simply not adequate to robustly characterize all system requirements and facilitate reliable design of complex care delivery systems. This is especially apparent in institutional-level systems, such as patient safety programs that must mitigate the risk of infections and other complications that can occur in virtually any setting providing direct and indirect patient care. The case example presented here illustrates the application of various system engineering methods to identify requirements and intervention candidates for a critical patient safety problem known as failure to rescue. Detailed descriptions of the analysis methods and their application are presented along with specific analysis artifacts related to the failure to rescue case study. Given the prevalence of complex systems in health care, this practical and effective approach provides an important example of how systems engineering methods can effectively address the shortcomings in current health care analysis and design, where complex systems are increasingly prevalent.

The purpose of this paper is to explore whether and how changes in the management control systems (MCS) of post-secondary institutions (PSIs) in Western Canada can be described and explained in terms of formal and informal MCS; and whether and how changes in the MCS of PSIs in Western Canada can be described and explained in terms of an integrative contingency-based framework of MCS based on regulatory accountability systems, competitive markets and organizational culture?

The empirical research was undertaken with an exploratory mixed design. The first phase involved descriptive univariate and bivariate statistics as well as non-parametric statistics computed on data from annual reports and financial statements of 46 PSIs in Western Canada to quantitatively explore MCS. The second phase involved the grounded theory (GT) analysis of annual reports of 46 PSIs in Western Canada to qualitatively explore formal MCS in relation to changes in contingencies. The third phase involved the GT analysis of 20 semi-structured interviews of senior managers from PSIs in Western Canada to qualitatively explore informal MCS in relation to formal MCS and changes in contingencies.

The research showed that emphasis on formal MCS in Western Canadian PSIs resulted in biased compliance within informal MCS. The exploratory research also demonstrated that the distinction between formal and informal MCS was better understood in a wider framing of MCS in terms of regulatory accountability systems, competitive markets and organizational culture.

This research led to the elaboration of an exploratory theoretical framework to subsume the distinction between formal and informal MCS into an integrative contingency-based framework of MCS.

Benchmarks are the vital tools in the performance measurement and evaluation of database management systems (DBMS), including the relational database management systems (RDBMS) and the object‐oriented/object‐relational database management systems (OODBMS/ORDBMS). Standard synthetic benchmarks have been used to assess the performance of RDBMS software. Other benchmarks have been utilized to appraise the performance of OODBMS/ORDBMS products. In this paper, an analytical framework of workload characterization to extensively and expansively examine the rationale and design of the industry standard and synthetic standard benchmarks is presented. This analytical framework of workload analysis is made up of four main components: the schema analysis, the operation analysis, the control analysis, and the system analysis. These analysis results are compiled and new concepts and perspectives of benchmark design are collated. Each analysis aspect is described and each managerial implication is discussed in detail.

Two main objectives and they are: to determine whether the internal audit department of the companies listed in the Bursa Malaysia complies with the Standards for the Professional Practice of Internal Auditors IIA (2000); and, to determine whether compliance to SPPIA will affect the quality of the internal control system of the company.

Two sets of questionnaires were used in the study. Internal auditing practices was measured by the items listed in the SPPIA and the internal control was measured by means of the statement on internal control: guidance for directors of public listed companies. The population used in this study was all the companies listed in the Bursa Malaysia in 2001. This study used both descriptive and inferential analyses.

It was found that management of internal audit department, professional proficiency, objectivity and review significantly influence the monitoring aspect of the internal control system. Scope of work and performance of audit work significantly influences the information and communication aspect of the internal control system while performance of audit work, professional proficiency and objectivity significantly influence the control environment aspect of the internal control system. The study also shows that management of internal audit department, performance of audit work, audit program and audit reporting significantly influences the risk assessment aspect of the internal control system. Lastly, performance of audit work and audit reporting significantly influences the control activities aspect of the internal control system.

The research has contributed to the agency theory with respect to the bonding costs that management has to pay to the internal auditors for the best interest of the principals of the companies. Another important implication pertains to the extent of the internal auditing practices among internal auditors in Malaysian public listed companies. Research has also shown that the compliance with internal auditing practices partially influence certain aspects of the quality of the internal control system.

This is the first empirical study that has linked the compliance of the internal auditing function to the SPPIA and its effect on the internal control system.

The purpose of this paper is to analyze how the COBIT framework, integrated within the internal control framework, enables improvement in the quality of financial reporting while helping to reduce or eliminate the material weaknesses (MWs) of internal control over financial reporting (ICFR). The Control Objectives for Information and Related Technology (COBIT) model is a framework for information technology (IT) management and IT governance. It is a supporting toolset that allows managers to bridge the gap between control requirements, technical issues and business risks. Preliminarily, the analysis in this paper illustrates how the Committee of Sponsoring Organizations (COSO) framework impacts on the MWs, highlighting strengths and weaknesses. This paper shows how these limits can be overcome with the use of the COBIT framework.

This is a conceptual paper that aims to highlight the relationship between COBIT and COSO, by illustrating how the IT processes reduce or eliminate the main MW categories.

The analysis indicates that the implementation of the COBIT framework, or more generally the adoption of effective IT controls, provides important benefits to the entire company or organization. IT control objectives have a direct impact on the IT control weaknesses and indirectly on the other categories of material weaknesses.

The adoption of the framework allows managers to implement effective ICFR. In particular, the COBIT approach provides managers with a more evolved tool in terms of compliance with the Sarbanes–Oxley Act requirements. This framework also improves the reliability of financial reporting in relation to the requirements of Public Company Accounting Oversight Board’s Auditing Standards No. 2 and 5.

The analysis provides an interdisciplinary approach, connecting accounting and information systems themes, and suggest solutions and tools than can help managers to address the internal control weaknesses. This paper addresses an area of relevance to both practitioners and academics and expands existing accounting literature.