Some Recurring Themes in Using Soft Systems Methodology

The object of inquiry in this paper is all organisation-based M.Sc. student projects of two consecutive years, using Soft Systems Methodology (SSM), undertaken as part of the course requirements at Lancaster University. This paper reports on a survey of 25 projects conducted by the group who originally developed SSM. No questionnaire that would trigger replies was used; rather, attending the students' project presentations at Lancaster after about four months in their client organisations brought to the fore those themes that the 45 users themselves deemed relevant during their use of SSM on the projects. This paper describes, discusses and analyses those themes, and relates them to each other. Reference to previous surveys is made and the consequences of the results presented are discussed.     

The Use of Soft Systems Methodology in the Development of a Simulation of Out-patient Services at Watford General Hospital

The effective and efficient provision of out-patient services may be assisted by the appropriate use of discrete event simulation. Resource use must be carefully monitored and suitable control actions must be taken, if service level and quality are to be maintained, whilst keeping cost increases to a minimum. In itself, simulation provides no means by which system activities may be identified. The use of soft systems methodology as a tool to aid in activity identification for simulation modelling is being explored. The investigation focuses on the effects the participative nature of soft systems methodology has on the acceptability of a simulation model. This case study forms part of a research objective of developing a generic approach to link soft systems methodology and simulation. Its aim is to provide analysts and managers with a process which may assist in planning strategies for health care.     

An application of Soft Systems Dynamics Methodology (SSDM)

The paper argues that by combining some of systems dynamics (SD) and soft systems methodology (SSM) stages, within the intellectual framework proposed by soft systems dynamics methodology (SSDM), a systemic methodology developed by Rodriguez-Ulloa, much can be gained in a systemic intervention when tackling complex social problematic situations. A framework for comparing the ontological, epistemological and methodological principles of SD, SSM and SSDM is proposed and the synthesizing role of SSDM is advanced. SSDM ten stages are briefly outlined and a full account of an application on a small Peruvian enterprise is presented. A reflection on SSDM as a systemic intellectual tool is proposed and conclusions together with points for further research are suggested.     

Soft OR and management practice: a study of the adoption and use of Soft Systems Methodology

The adoption and use of Soft Systems Methodology (SSM) within management practice is the central focus of the reported research study. The paper concentrates upon the extent to which SSM has been adopted and integrated into the management practice of 349 members of the Systems Study Group (SSG) of the Queensland Department of Primary Industries (QDPI). The study builds upon and complements previous work that surveyed the use of Soft Systems Methodology in the United Kingdom. Although the results of the study are consistent with the previous research, the level of adoption is found to be much higher than anticipated and the form of adoption differs considerably from the UK study. Users are found to fall into two main groups; those that use the core elements of SSM and those that do not. However, both groups report successful use of the approach but yet again the attribution of success falls into two main categories, namely sense making and change management. It is concluded that a positive impact of SSM upon management practice can be demonstrated but that the nature of the impact remains unclear.     

Using a model of the performance measures in Soft Systems Methodology (SSM) to take action: a case study in health care

This paper uses a case study of a multidisciplinary colorectal cancer team in health care to explain how a model of performance measures can lead to debate and action in Soft System Methodology (SSM). This study gives a greater emphasis and role to the performance measures than currently given in typical SSM studies. Currently, the concept of performance measurement in SSM is in the form of a set of criteria used to judge the performance of the SSM model (the purposeful activity model). These performance criteria are definitions of efficacy, efficiency, effectiveness, ethicality and elegance. However, the use of performance measures within SSM is not clear and therefore criticized by some as nebulous. This paper uses a case study to explain how to involve the stakeholders in deriving a performance measurement model (PMM), which is a more detailed expansion of the performance criteria. The paper concludes with some reflections about how the PMM can fit in the SSM cycle, with two modes of practice put forward.     

The Use of Characteristic Functions and Characteristic Values in Feedback Systems Analysis

The role played by the concepts of characteristic values and characteristic functions in modern control theory is briefly outlined. It is then shown that, by introducing the idea of a characteristic transfer function, the classical stability theorem of Nyquist can be extended to the general multivariable feedback system.     

Soft Systems Models for Knowledge Elicitation and Representation

The paper contends that the conceptual modes used in Soft Systems Methodology have an unusual logical status. This enables them to be rendered in modal logic and used as a framework for knowledge elicitation and for the design of knowledge-based systems with learning capability.     

非线性转子系统稳定性量化分析方法

转子轴承系统是一类多自由度非线性动力系统,广泛应用于工程实际．设计观念和维修体制的变革提出了稳定性量化分析的要求．本文利用轨线保稳降维方法提出了转子系统稳定性的量化分析方法．首先,对高维非线性非自治转子系统进行数值积分,将n维空间的轨线映射为一系列一维的映象轨线,并将各自由度的运动方程中除该自由度外的所有状态变量用积分结果代换,得到n个互相解耦,含有多个时变参数的单自由度方程．然后,在一维观察空间的外力位移扩展相平面上定义了动态中心点,研究转子系统中常见的几种运动的动态中心点动能差序列的特点,给出了上述典型运动形式的轨线稳定裕度的定量评估指标,应用灵敏度分析技术快速有效地预测周期运动的倍周期分岔点和Hopf分岔点．以一个具有非线性支承的滑动轴承柔性转子模型为例,证明了该方法的有效性．     

The Use of Index Numbers for Measuring Output of Multi-Product Systems

Measurement of output for a multi-product system often relies on revenue as a yardstick, but such an approach is inadequate for measures of physical output or aggregate price. Many alternative methods, based on the use of index numbers, are outlined and compared for a simple example. The strengths and weaknesses of these methods are discussed, and ways of overcoming difficulties due to discontinuities in the product range are suggested.     

种群生态系统中的模糊软测量方法

经典的生物模型中,关键参数的难以测量使整个动力系统具有较大的不确定性.本文引入模糊软测量技术,以湿地环境中三种群生态系统为例,将软洲量技术与模糊系统结合应用于种群动力学模型,以种群数量的初始值、时间t及种群变化率为辅助参数进行种群数量的预测.运用软测量技术估计微分方程中关键参数(如竞争系数、最大捕获率、能量转换系数),建立确定的动力学微分方程模型.仿真结果显示此方法的可行性、有效性.