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Radio-frequency circuits often possess a multi-rate behavior. Slow changing baseband signals and fast oscillating carrier signals often occur in the same circuit. Frequency modulated signals pose a particular challenge. The paper aims to discuss these issues.

The ordinary circuit differential equations are first rewritten by a system of (multi-rate) partial differential equations in order to decouple the different time scales. For an efficient simulation the paper needs an optimal choice of a frequency-dependent parameter. This is achieved by an additional smoothness condition.

By incorporating the smoothness condition into the discretization, the paper obtains a non-linear system of equations complemented by a minimization constraint. This problem is solved by a modified Newton method, which needs only little extra computational effort. The method is tested on a phase locked loop with a frequency modulated input signal.

A new optimal frequency sweep method was introduced, which will permit a very efficient simulation of multi-rate circuits.

The Israeli National Police began to implement community policing on a large scale in January of 1995. In this paper we describe the main findings of a three year national evaluation of community policing in Israel that was initiated by the Chief Scientist’s office of the Israeli police in the Fall of 1996. When community policing was envisioned and planned in Israel it was seen as part of a total reformation of the Israeli police in structure, philosophy and action. Our research suggests that this broad idea of community policing was not implemented in Israel, and indeed the program of community policing was found to lose ground during the course of our study. While community policing did have specific impacts on the Israeli police, it did not fundamentally change the perspectives and activities of street level police officers. We explain the difficulties encountered in the implementation of community policing in reference to three factors: the speed of implementation of the program; the resistance of traditional military style organizational culture within the Israeli police to the demands of community policing models; and a lack of organizational commitment to community policing. In our conclusions we argue that these barriers to successful community policing are not unique to the Israel case, and are indeed likely to be encountered in the development of community policing in many other countries.

The spread of broadband Internet has resulted in the increase of spyware and adware. This study highlights their damaging effects and proposes a model that captures defensive measures adopted by Internet users. Specifically, our model indicates that knowledge has a positive impact on self‐efficacy that, in turn, is presumed to trigger technical defensive measures. Moreover, concerns for privacy and previous experience with spyware and adware are likely to evoke both tactical and technical defense measures. Data collected by the PEW Internet and American Life research project are utilized to test the proposed model and the findings are discussed.

The authors examined the cardiac care pathway with the aim of identifying factors that impact on diagnosis and treatment of coronary heart disease in British Pakistani women.

This is an exploratory qualitative study. In depth interviews and focus groups with an opportunistic sample of Pakistani women and a purposive sample of clinicians working at different points along the care pathway were conducted. The authors used a pathways to care approach to illustrate how their individual and cumulative effect may contribute to differential receipt of treatment, including revascularisation, and health inequalities.

Four major issues were identified: complex life circumstances; “atypical” presentation and symptomatology; problems related to investigative testing; and poor communication. Mapping these barriers onto the Pathways to Care Model provided valuable insight into their impact on patients' progression through the different stages of the care pathway.

Adopting a care pathway approach demonstrated how individual factors have an impact at several points along the care pathway. It indicated where further, more detailed enquiry is merited and where intervention studies might usefully be directed to improve care.

Examining the whole care pathway identified areas of service improvement that merit a co‐ordinated response.

The framework provided by the Pathways to Care Model offered insight into the causes of the previously observed attenuation in women's progress along the cardiac diagnosis and treatment pathway and is an important first step to addressing this health inequality in a holistic way.