Jozsef Klespitz

Identification and control of peristaltic pumps in hemodialysis machines

In hemodialysis machines peristaltic pumps are responsible for the transfer of fluids. The main characteristic of these pumps is that they can transport the solutions with significant error. That depends on the tube segment deviation caused through the production. Due to the fact that the medical fluid represents sometimes drugs and in the same time it is required to control the fluid balance of the patient, it is important to transfer these fluids as accurate as possible. The goal of the paper is to design a controller that satisfies the mentioned requirements. First, the system identification is realized by classical moving average method (ARX), followed by the design of two controllers: a classical PID one and a fuzzy controller. After comparing their simulation results, the most preferable one was implemented in practice. Real simulation results of the implemented controller end the paper.

Application of fuzzy logic in hemodialysis equipment

In hemodialysis machines peristaltic pumps are responsible for the transfer of fluids. These pumps can only deliver the solutions with significant error, due to the deviation of the pump head and due to production errors. Previous work focused on system identification and fluid flow control by a PID controller. In this paper the goal is to replace the PID controller with an adaptive fuzzy controller. Furthermore, the use of integral component for error signal rejection is examined as input to the fuzzy logic system. The mentioned controllers are compared through appropriate aspects and the paper ends with discussion of the behavior of the adaptive fuzzy controller on the real system.

Aspects of improvement of software development lifecycle management

The software development lifecycle management is a crucial aspect of software development, as it defines significantly the effectiveness of development and the maturity of the final product. A suitable management system is especially important in safety critical development, such as the development of medical devices, as these developments have to be well documented to prove the safe operation of the given instrument. This paper prepares a case study to help a company improving their existing lifecycle management system by establishing a group of requirements. In particular, the paper focuses on medical device software development aspects. The answering of these questions allows achieving an optimal choice among the possible management systems either by providing a quantitative comparison or by highlighting the grounds for exclusion.

Peristaltic pumps — A review on working and control possibilities

Peristaltic pumps are positive replacement pumps, commonly used in fluid transports. These pump does not contaminate the transported fluid, they are undemanding and ideal for shear-sensitive and aggressive fluids. Through their wide spectrum of use, there are many variants of these pumps based on their special needs, such as high pressure need, long tubing lifetime or low pressure deviation. The object of this paper is to review and summarize the most important properties of these pumps and introduce some of the special solutions of these pumps focusing on control engineering possibilities.

Evaluation criteria for application life cycle management systems in practice

The effective use of (human) resources and a mature product assumes the application of a software development life cycle (SDLC) management system which actively supports the process of development. A well-adjusted SDLC system is a prerequisite in safety-critical developments, such as the development of medical devices. Otherwise, the intensive documentation needed proving the correct and safe operation of the equipment cannot be fulfilled. The aim of this paper is to provide structured and mostly quantified criteria for companies which plan to establish newly an application life cycle management system or improve an existing one. The answering of these question helps making an objective and optimal choice among the different systems. Finally, this paper prepares a case study, where the application of these criteria will be demonstrated in practice.

Towards automated traceability assessment through augmented lifecycle space

The assessment and improvement of the satisfaction of traceability requirements during the development of software in general and of safety-critical software in particular is demanding and costly. The special requirements are reflected in software process related general and industry specific standards and the popular agile approaches as well. It is imminent, for practical and logical reasons, that there is a need for the automation of the assessment of the completeness and consistency of traceability as far as possible. In addition to highlighting experienced weaknesses of current either homogeneous or heterogeneous tool environments intending to support development lifecycle traceability, this paper outlines new solutions and suggests the exploitation of emerging technologies for the automation of traceability assessment and improvement.

Model-based healthcare applications at Óbuda University

Following the tradition established at previous IEEE INES conferences, this paper presents the results achieved by the Physiological Controls Group of Óbuda University in the field of physiological control last year (2013). The application target was focused on diabetes (artificial pancreas), tumor (antiangiogenic therapy), and hemodialysis (control of peristaltic pumps).

Graceful Integration of Process Capability Improvement, Formal Modeling and Web Technology for Traceability

This paper discusses the need and leveraging potential of formal modeling and web technology for progressing towards the goal of automating the establishment, maintenance and assessment of the completeness of traceability and the consistency of the requirements. The generic Augmented Lifecycle Space method, devised in an earlier paper, is applied as the approach to improve the capability of software processes requiring bidirectional traceability as well as consistency of the requirements in either homogeneous or heterogeneous development environments capitalizing on the emerging Open Services for Lifecycle Collaboration (OSLC) initiative. One of the important features of the presented new approach is that it allows for the so called “graceful integration” of formal modeling. Formal modeling is fundamentally necessary for securing completeness and consistency, but customarily rejected due to the usually prohibiting up-front effort needed to formally process all artifacts of an already established traditional system; Graceful integration can considerably lower this threshold.

Augmented Lifecycle Space for traceability and consistency enhancement

In software development application lifecycle management (ALM) systems are used to support the development process. As these products are tailored for best fitting the applied programs and their actual usage is diverse. Often, this means that products of different vendors are applied, which reduce the reachability between different artefacts and the overall consistency of the system. In this paper we are analyzing the applicability of Augmented Lifecycle Space as a new approach. This approach provides the capability to enhance the traceability and consistency while reducing human effort through automation both in homogeneous and heterogeneous tool environments.

Enhanced traceability and consistency with Augmented Lifecycle Space

Modern software development is unimaginable without the help of Application lifecycle management systems (ALMs) due to the heavy documentation and communication needs, especially in safety-critical developments. In this paper the idea of Augmented Lifecycle Space is presented together with its use and benefits. The main target of application is to enhance traceability and consistency throughout the development with minimal or reduced human effort. The idea can be realized easily in homogeneous ALM systems. In case of heterogeneous systems, which is the main scope of this research, some kind of interoperability is required among the used tools. Open Services for Lifecycle Collaboration (OSLC) is a possible solution and it is used to illustrate a possible setup for further studies.