A stabilising control strategy for Cyber-Physical Power Systems

The cyber-physical nature of electric power systems has increased immensely over the last decades, with advanced communication infrastructure paving the way. It is now possible to design wide-area controllers, relying on remote monitor and control of devices, that can tackle power system stability problems more effectively than local controllers. However, their performance and security relies extensively on the communication infrastructure and can make power systems vulnerable to disturbances emerging on the cyber side of the system. In this paper, we investigate the effect of communication delays on the performance of wide-area damping controllers (WADC) designed to stabilise oscillatory modes in a Cyber-Physical Power System (CPPS). We propose a rule-based control strategy that combines wide-area and traditional local stabilising controllers to increase the performance and maintain the stable operation of CPPS. The proposed strategy is validated on a reduced CPPS equivalent model of Great-Britain (GB)

Electrostatically stabilised nanoparticles : Self-organization and electron-beam patterning

The self-organisation of citrate- and magnesium oleate-stabilised gold nanoparticles on SiO2/Si substrates was investigated. In drop deposition, nucleation of citrate-stabilised gold nanoparticles was observed at the rim of the droplet, symmetric or multibranched dendroid gold structures were found in the area between the rim and the central part of the droplet, depending on the drying temperature. Homogeneous submonolayer nanoparticle coverage was obtained by immersion of amine-terminated SiO2/Si surfaces into a citrate-stabilised colloidal gold acidic solution. Drop deposition of magnesium oleate-stabilised gold nanoparticles onto the SiO2/Si surfaces resulted in the formation of uniformly close-packed nanoparticle arrays. Under electron beam irradiation, no apparent changes were found for monolayer films of citrate-stabilized particles, but sintering of the nanoparticles was observed in multilayer films. In contrast, coalescence of magnesium oleate-stabilised gold nanoparticle occurred in monolayer films after electron irradiation

Condemned to rootlessness: the loyalist origins of Canada's identity crisis

Few observers have sought to explain why French Canadians, Metis and even Anglo‐Americans developed a sense of indigenous ethnicity while English‐Canadians failed to do the same. Fewer still have sought to connect this to the national ‘identity crisis’ often mentioned in the discourse of English‐speaking Canada. This article asserts that English Canada's perception of a ‘Canadian’ identity crisis is really an English‐Canadian one which has its roots in English Canada's Loyalist ethnic core. In contrast to most nations, English Canada never developed an indigenous ethnic core. Instead, its ‘non‐ethnic’ identity, from its Loyalist beginnings, remained split. On one side was a repressed American folk culture, which outsiders used to recognize the English‐Canadians. On the other was an exalted set of British myths, symbols and narratives, to which English‐Canadians attached themselves. The pattern of English‐Canadian cultural history is therefore unsurprising: it involves a tension between American and British influence, with seemingly no exit. Thus the ‘Canadians’, deprived of a distinct founding people, were, from the beginning, ‘condemned to rootlessness’

The Emotion Regulation Questionnaire: Psychometric properties and relations with affective symptoms in a United States general community sample

Background Difficulties in emotion regulation are a key risk factor for affective disorders. The Emotion Regulation Questionnaire (ERQ) is a 10-item measure of two emotion regulation strategies, cognitive reappraisal and expressive suppression. It is widely used tool in the United States, however, most psychometric studies of the ERQ have so far been conducted with college students and some researchers have recently questioned its factorial validity in non-student samples. In this study, we conducted the first confirmatory factor analysis study of the ERQ in a United States general community sample. Method We examined the ERQ's factor structure, measurement invariance across age, education and gender categories, internal consistency reliability, and concurrent validity with a sample of 508 adults. Results The intended two-factor model (cognitive reappraisal, expressive suppression) was an excellent fit to the data, and this structure was invariant across different age, education, and gender categories. Both ERQ scale scores had good omega and alpha reliabilities, and correlated as expected with depression and anxiety symptoms. Cognitive reappraisal was negatively correlated with these symptoms, whereas expressive suppression was positively correlated with these symptoms. Limitations We did not include a clinical sample and future psychometric studies of the ERQ in specialised clinical populations would be useful. Conclusions The ERQ appears to have strong psychometric properties when used with general community members from the United States. ERQ scores can be confidently used and compared across adults of different ages, genders, and educational backgrounds

Gold nanoparticle patterning of silicon wafers using chemical e-beam lithography

This paper demonstrates a novel facile method for fabrication of patterned arrays of gold nanoparticles on Si/SiO2 by combining electron beam lithography and self-assembly techniques. Our strategy is to use direct-write electron beam patterning to convert nitro functionality in self-assembled monolayers of 3-(4-nitrophenoxy)-propyltrimethoxysilane to amino functionality, forming chemically well-defined surface architectures on the 100 nm scale. These nanopatterns are employed to guide the assembly of citrate-passivated gold nanoparticles according to their different affinities for amino and nitro groups. This kind of nanoparticle assembly offers an attractive new option for nanoparticle patterning a silicon surface, as relevant, for example, to biosensors, electronics, and optical devices