Response of YBCO/PCBO/YBCO ramp type Josephson junctions to near MM wave irradiation

A high Tc Josephson device for high frequency detection applications is being developed, consisting of an YBCO/PBCO/YBCO ramp type junction and a broad band log-periodic antenna. In this contribution we present the response of such a device to (near) mm wave irradiation. Shapiro steps have been observed up to very high voltage values - nearly 4 mV at 10 K, at the maximum of the radiation power. The modulation of the step amplitudes shows very good resemblence with the predictions from the Resistively Shunted Junction model

Great Expectations? Assessing the creation of national police organisations in Scotland and the Netherlands

Against a background of recent structural reforms to police organisations in northern and western Europe, this paper examines the experiences of Scotland and the Netherlands where national police forces were established in 2013. Taking a comparative perspective, an analysis of the police reform proposals is followed by a review of the arguments for reform, the challenges of implementation and the findings emerging from the evaluations of the police reforms in each country. The paper concludes by drawing out the contrast between the ‘great expectations’ of the two police reforms articulated by the governments and the realities of bringing about rapid and large-scale organisational change, arguing that institutionalist perspectives on police reform have much to offer in making sense of the challenges of the police reform process

Identifying Strategies for English Language Learner Literacy Development at the Secondary Level Using Whole-class Readings

This study seeks to identify literacy strategies that support English language learner literacy development in secondary English courses. The study occurs over a six-week unit where whole-class reading of the novella Animal Farm takes place. The study features qualitative methods of data collection and analysis situated in an advocacy, change-oriented perspective. Data include teaching journal entries, lesson plans, field notes, student conference interviews (conferring notes), and student records and artifacts. Constant comparison and grounded theory methods of analysis are used, along with open coding and pattern matching. Findings reveal four emergent patterns that have a significant positive correlation to comprehension, participation, and academic achievement: the frequency of teacher read-alouds, the use of visual aids with graphic organizers, the use of group activities as part of scaffolding exercises, and sustained repetition of strategies and material

The Abstract Police:a conceptual exploration of unintended changes of police organizations

Contains fulltext : 208720.pdf (publisher's version ) (Open Access)21 p

Testing theory in practice: a simple experiment

In this paper we discuss the experiences gained in conducting a simple testing experiment. The goal of this experiment is to apply the abstract, formal testing framework [8] in a practical setting, and to indicate the critical aspects in its application to realistic testing situations. For that purpose a formal description of the system under test (SUT) is made from which tests are systematically derived. These tests are interpreted and executed by a tester against concrete implementations, thereby giving an indication about the correctness of these implementations

Noise study of a high‐Tc Josephson junction under near‐millimeter‐wave irradiation

Noise studies of both the dc and ac Josephson effects have been performed on a high‐Tc ramp‐type Josephson junction irradiated at 176 GHz. Well‐established analytical results for noise in overdamped RSJs are used to model the measured I‐V characteristics, and their agreement is excellent. Noise‐rounded I‐V curves at the critical current and the first and second Shapiro steps under coherent 176 GHz radiation have been studied in detail at several temperatures and rf power levels. The noise temperatures inferred from these simulations are close to the physical temperatures. An increase of noise temperatures at high radiation power levels is a result of radiation heating, which could be due to a bolometric effect

Total aqueous processing of carbothermally produced beta-sialon

ß-Sialon with chemical formula Si3Al3O3N5 is synthesized from meta-kaolin/coal mixtures which are pelletised and heat treated at 1500 °C in flowing nitrogen. Typically batches produced contain 300 g powder with 90 wt% ß-sialon and 10 wt% 15-R phase. The powders are attrition milled to submicron size, suspended in water and mixed with yttrium oxide as a sintering aid. Suspensions are pH and polyelectrolyte stabilised. The suspensions are used to slip cast discs which are sintered in a nitrogen atmosphere of 100 kPa at 1450 °C for 150 minutes. Typical properties are ball-on-ring strength at room temperature 450 MPa, density 3.31 g/ml, HV2 Vickers hardness 12.5 GPa and KIC 5.4 MPa v