Submillimeter wave frequency selective surface with polarisation independent spectral responses

This paper reports the design, construction and electromagnetic performance of a new freestanding frequency selective surface (FSS) structure which generates coincident spectral responses for dual polarisation excitation at oblique angles of incidence. The FSS is required to allow transmission of 316.5 - 325.5 GHz radiation with a loss = 0.6 dB and to achieve = 30 dB rejection from 349.5 - 358.5 GHz. It should also exhibit crosspolarisation levels below -25 dB, all criteria being satisfied simultaneously for TE and TM polarisations at 45° incidence. The filter consists of two identical, 30 mm diameter, 12.5 ?m thick, optically flat, perforated metal screens separated by 450 ?m. Each of the ˜5000 unit cells contains two nested, short circuited, rectangular loop slots and a rectangular dipole slot. The nested elements provide a passband spectral response centred at 320 GHz in the TE and TM planes; the dipole slot increases the filter roll-off above resonance. The FSS was fabricated from silicon-on-insulator wafers using precision micromachining and plating processes including the use of Deep Reactive Ion Etching (DRIE) to pattern the individual slots and remove the substrate under the periodic arrays. Quasi–optical transmission measurements in the 250 – 360 GHz range yielded virtually identical copolarised spectral responses, with the performance meeting or exceeding the above specifications. Experimental results are in excellent agreement with numerical predictions.

The Definition of Slavery in International Law

On the basis of archival research, this Article considers the negotiation history of both the 1926 Slavery Convention and 1956 Supplementary Convention and demonstrates that an interpretation of the provisions of the definition of slavery consonant with the travaux préparatoires reveal a definition which provides for the possibility of holding States and individuals responsible for not only slavery de jure but also de facto. That understanding is premised on a reading of the definition that speaks not of the ‘ownership’ of one person by another; but of the powers attached to the right of ownership. It is through an exploration of this phrase that a proper understanding of the definition of slavery in international law emerges.

Reconsidering Respect: Its Role in the British Prison Service

This article examines the meaning of respect in the interpersonal relationships within Her Majesty’s Prison Service. It is argued that respect-as-esteem and respect-asconsideration are often confused and unequally emphasised in modern society. This confusion is especially evident within the prison context where, due to the prison service’s ‘decency agenda’, the respectful treatment of inmates has become a topical issue. What does respect mean in prison? Why is it important? How can respectful relationships be established between staff and inmates? This article discusses these questions and proposes that there are different forms of respect possible between people. It is argued that there needs to be a recognition of the nuances of meaning when we use the word respect and that ‘respect-as-consideration’ may be the form of respect most consistently achievable, at the present time, within interpersonal relationships in English and Welsh prisons.