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The aim of this paper is to add to understanding of how cities function. Specifically, through the lens of power relationships in political organisations, it seeks to study the manner in which accounting and politics are involved in the development of city transport strategies.

The paper uses a comparative case study approach in which documents and media coverage are key elements of the visualising of the city.

The findings are on a number of levels. First, the study explains the efficacy of congestion charging systems. Second, in the politicised organisation of the city, the context in which policy makers sit is crucial in the elaboration of strategies. Third, the adoption of calculative practices such as congestion charging may reflect political rationality rather than actual need.

The focus of the study has been cities – a neglected field, but one with considerable research potential. Second, the mobilisation of concepts of power, as articulated by Clegg, Flyvbjerg and Clegg, represent a novel contribution to the accounting literature.

Let \cal N be a consistent connected network including independent voltage and current sources, positive linear resistors, multiterminal weakly no‐gain non‐linear resistors and equal numbers of nullators and norators, U(\cal N) a voltage appearing between a distinguished pair of nodes and I(\cal N) a current flowing in a distinguished branch in an equilibrium state of \cal N. It is proved that, under conditions detailed in the paper, U(\˜cal N¹)≤ U(\cal N) ≤ U(\˜cal N²) and I(\overline \cal N^\raise1pt1) ≤ I(\cal N) ≤ I(\overline \cal N^\raise1pt2) where \˜cal N¹,\˜cal N²,\overline \cal N^\raise1pt1, and \overline \cal N^\raise1pt2, are networks derived from \cal N by replacing non‐linear resistors by open‐ and/or short‐circuit structures. An earlier combinatorial method of estimating solutions of non‐linear resistive networks is extended to cover networks including active elements. The method is tested on simple examples of active diode‐transistor circuits.

Introduction Depending on the way of teaching process organization the theory of electromagnetic field is considered either as a part of theoretical electrical engineering or as an individual subject. The electromagnetic field theory plays a double role in the education of electric engineers: comprehensive or specialized one. However, the electromagnetic field can be treated from the other point of view. It can be lectured with pointing out the calculation methods or phenomena occurring in “pure” electromagnetic field, and on the other hand, with reference to phenomena occurring in coupled fields, where those fields are affecting non‐living or having objects.

The aim of this article is to draw attention to the importance of open discussion for the proper development of science.

In the phase of the developed market economy we are currently in, the evaluation of each human activity, including scientific work, which is based on an evaluation of the value of the profit it brings. Unfortunately, it does not always work correctly.

The problem will be analyzed using as an example the erroneous (according to the author) use of fractional derivatives in electrical engineering.

To the best of the author’s knowledge, this is the author's original point of view on the problem of improper use of fractional derivatives in electrical engineering.

While working with clients in the last years of his life, Gordon Pask produced an axiomatic scheme for his Interactions of Actors Theory which is a development of his well known Conversation Theory. These axioms are interpretable as a general theory of self‐organisation and are discussed as characteristic of field concurrence and as part of the second‐order cybernetics canon. An application to population density is reported supported by both kinematic and kinetic simulation. Implications for cardiovascular anti‐coagulation therapy and planetary evolution are discussed.

In times when digitized and blended learning paradigms are getting more profuse, the COVID-19 pandemic substantially changed the dynamics of this program, forcing all the courses to migrate to virtual modality. This study highlights the biological engineering courses at the University of the Republic (Universidad de la República) in Uruguay pertaining to the adaptations to virtual learning environments during the COVID-19 pandemic and analyzing its impact through the courses taught in the virtual setting.

Global education has seen a significant paradigm shift over the last few years, changing from a specialized approach to a broader transdisciplinary approach. Especially in life sciences, different fields of specializations have started to share a common space in the area of applied research and development. Based on this transdisciplinary approach, the Biological Engineering program was designed at the University of the Republic (Universidad de la República), Uruguay.

The new challenges posed by the virtual modality on the pedagogical areas like course design, teaching methodologies and evaluations and logistical aspects like laboratory-setting have sparked a considerable change in different aspects of the courses. However, despite the changes to virtual modality in this year, the student-performance showed an overall improvement compared to the last year.

With the changing direction of pedagogy and research in biological engineering across the world, it is quintessential to adapt university courses to the same, promoting an environment where the scientific and engineering disciplines merge and the learning methodologies lead to a dynamic and adaptive ubiquitous learning environment.

A network composed by RC distributed parameter lines with resistively grounded nodes is considered. Upper and lower bounds for the transient voltages are inferred. The results are of interest for the signal delay evaluation in VLSI interconnections. A numerical example is presented.

Bang‐bang clock and data recovery (BBCDR) circuits are hard nonlinear systems due to the nonlinearity introduced by the binary phase detector (BPD). The specification of the CDR frequency response is determined by jitter tolerance and jitter transfer. In this paper, jitter transfer and jitter tolerance of the BBCDR are characterized.

The presented method is enough to be used for designing the BBCDR loop parameters.

In this paper, jitter characteristics of the BBCDR are characterized. As a result, a new equation is presented to obtain angular frequency. Also, the jitter tolerance is expressed in closed form as a function of loop parameters. The analysis is verified using behavioral simulations in MATLAB. Simulation results show that good conformance between analytical equations and simulation results.

The proposed approach offers two advantages compared to conventional designing methods. First, this approach does not consider any value restriction to the capacitor. Second, a new condition has been presented to guarantee that the value of jitter peaking is approximately zero.

The purpose of this paper is to clarify the method of using RF impedance changes as an early indicator of degradation of solder joint. It proposes the mode of crack propagation in solder joint and outlines why RF impedance analysis can be capable of detecting small cracks. The study aims to show the potential of RF impedance analysis as a prognostic tool that can provide advanced warning of impending failures of solder joint.

In this paper, the mode of crack propagation in solder joint was studied to show why RF impedance analysis could be capable of detecting small cracks. A real simple impedance‐controlled test vehicle was developed to allow RF impedance and DC resistance measurements to monitor solder joint degradation. The influence of crack length on RF impedance was evaluated by high frequency structure simulator (HFSS) simulation for the first time.

The paper demonstrates that RF resistance can respond to an open state of a solder joint as well as DC resistance. Furthermore, RF impedance can monitor partial degradation of solder joints, while the DC resistance cannot do it. In addition, time‐domain reflection coefficient is found to be more useful than RF impedance in detecting solder joint degradation. The HFSS simulation results show that even very slight physical degradation of solder joints can be detected using RF impedance analysis.

In this paper, HFSS simulation is used for the first time to evaluate the influence of crack length on RF impedance.

The purpose of this paper is to propose methods to improve the least square error polynomial fitting of multi-input nonlinear sources that suffer from strong correlating inputs.

The polynomial fitting is improved by amplitude normalization, reducing the order of the model, utilizing Chebychev polynomials and finally perturbing the correlating controlling voltage spectra. The fitting process is estimated by the reliability figure and the condition number.

It is shown in the paper that perturbing one of the controlling voltages reduces the correlation to a large extend especially in the cross-terms of the multi-input polynomials. Chebychev polynomials reduce the correlation between the higher-order spectra derived from the same input signal, but cannot break the correlation between correlating input and output voltages.

Optimal perturbations are sought in a separate optimization loop, which slows down the fitting process. This is due to the fact that each nonlinear source that suffers from the correlation needs a different perturbation.

The perturbation, harmonic balance run and refitting of an individual nonlinear source inside a device model is new and original way to characterize and fit polynomial models.