Signal acquisition via polarization modulation in single photon sources

A simple model system is introduced for demonstrating how a single photon source might be used to transduce classical analog information. The theoretical scheme results in measurements of analog source samples that are (i) quantized in the sense of analog-to-digital conversion and (ii) corrupted by random noise that is solely due to the quantum uncertainty in detecting the polarization state of each photon. This noise is unavoidable if more than one bit per sample is to be transmitted, and we show how it may be exploited in a manner inspired by suprathreshold stochastic resonance. The system is analyzed information theoretically, as it can be modeled as a noisy optical communication channel, although unlike classical Poisson channels, the detector's photon statistics are binomial. Previous results on binomial channels are adapted to demonstrate numerically that the classical information capacity, and thus the accuracy of the transduction, increases logarithmically with the square root of the number of photons, N. Although the capacity is shown to be reduced when an additional detector nonideality is present, the logarithmic increase with N remains.Comment: 7 pages, 2 figures, accepted by Physical Review E. This version adds a referenc

Ghana airborne geophysics project in the Volta and Keta Basin : BGS final report

This report describes the work undertaken by BGS between November 2006 and March 2009 in collaboration with Fugro Airborne Surveys Pty Ltd on an airborne geophysical survey and ground reconnaissance mapping of the Volta River and Keta Basins, Ghana. The project was supported by the EU as part of the Mining Sector Support Programme, Project Number 8ACP GH 027/13. The initial contract duration was three years, but this was extended by five months to account for acquisition of gravity data by another project. Some parts of Ghana have been airborne surveyed as part of the Mining Sector Development and Environmental Project, co-funded by the World Bank and the Nordic Development Fund, but no work was carried out on the Volta River and Keta basins, which together form a major portion of the Ghanaian territory. The approximate areas covered by the surveys are estimated at 98,000 km² for the satellite imagery and the airborne geophysics, except for the Time Domain Electromagnetic (TDEM) survey which was limited to 60,000 km². The main beneficiary of this project is the Geological Survey Department, GSD. The work enhanced its geological infrastructure and its personnel received hands-on training on modern geological mapping technology. Indirect beneficiaries were the mining and exploration companies that can follow up the reconnaissance work with detailed exploration work. The project was conducted in five phases, and this document reports on the BGS input to Phase 1, 4 and 5, with no inputs required in Phases 2 and 3: • Phase1: geological outline through Radar and optical satellite imageries. • Phase 2: airborne geophysical survey over the two basins for magnetics and Gamma Ray spectrometry (Fugro survey). • Phase 3: airborne electromagnetic and magnetic geophysical survey of specific areas, following the completion and interpretation of phase 2, using fixed wing time domain technology (Fugro survey). • Phase 4: interpretation of the combined geology and geophysics. • Phase 5: production of factual and interpretation maps. The full list of BGS products is outlined in Table 1 below, while Jordan et al. (2006) describe the products delivered on schedule in Phase 1

Pooling stated and revealed preference data in the presence of RP endogeneity

Pooled discrete choice models combine revealed preference (RP) data and stated preference (SP) data to exploit advantages of each. SP data is often treated with suspicion because consumers may respond differently in a hypothetical survey context than they do in the marketplace. However, models built on RP data can suffer from endogeneity bias when attributes that drive consumer choices are unobserved by the modeler and correlated with observed variables. Using a synthetic data experiment, we test the performance of pooled RP–SP models in recovering the preference parameters that generated the market data under conditions that choice modelers are likely to face, including (1) when there is potential for endogeneity problems in the RP data, such as omitted variable bias, and (2) when consumer willingness to pay for attributes may differ from the survey context to the market context. We identify situations where pooling RP and SP data does and does not mitigate each data source’s respective weaknesses. We also show that the likelihood ratio test, which has been widely used to determine whether pooling is statistically justifiable, (1) can fail to identify the case where SP context preference differences and RP endogeneity bias shift the parameter estimates of both models in the same direction and magnitude and (2) is unreliable when the product attributes are fixed within a small number of choice sets, which is typical of automotive RP data. Our findings offer new insights into when pooling data sources may or may not be advisable for accurately estimating market preference parameters, including consideration of the conditions and context under which the data were generated as well as the relative balance of information between data sources.This work was supported in part by a grant from the Link Foundation, a grant from the National Science Foundation # 1064241 , and a grant from Ford Motor Company. The opinions expressed are those of the authors and not necessarily those of the sponsors.Accepted manuscrip

Community Based Learning, and how this Policy can be Applied to Enhance the Learning Experience for Students on the Degree Course in Construction Economics and Management

A study investigating the Dublin Institute of Technology’s policy regarding Community Based Learning, and how this policy can be applied to enhance the learning experience for students on the degree course in Construction Economics & Management

起死回生(Resuscitation): Japan\u27s Search for Machines and their Meanings

Japan’s lost decade(s) ushered in a new era of economic and societal malaise, marked by a shrinking population, an increased proportion of elderly people, inequality, neo-nationalism(s), uncertainty, and isolation. This project seeks to understand how Japan is trying to address these issues and reconstruct itself from the lost decade(s) with the use of artificial intelligence (jinkou chihou) and robotics along with the societal implications of this technology. This interdisciplinary research utilizes innovative, historical narratives (Morris-Suzuki,1988, Hornyak 2006), and the socio-cultural milieu of Japan and its traditions (Allison 2013; Katsuno 2010) to further appreciate and acknowledge Japanese perspectives and thought on AI and robotics and their uses. Furthermore, investigating government-issued publications (Innovation 25; New Robot Strategy; Japan Revitalization Strategy), and contemporary literature by AI field experts (Harari 2017; Bostrom 2017; Frase 2016), this paper argues that Japan’s futurist visions do not take into account the problematic ramifications of AI. In so doing, this paper critically reimagines a best response and re-envisioning of an unfolding and possible future. Research findings may also hold significance in other cultural and national contexts, particularly in nations with shrinking and aging populations, class stratification, and ethnic and techno-nationalism(s)

The Relevance of Teaching Traditional Measurement Techniques to Undergraduate Quantity Surveying Students.

Measurement of quantities is a core skill which must be inherent in all graduates from Quantity Surveying courses. Many students find this subject difficult to grasp, and the learning experience can be problematic especially in the first semester of first year. This is not unique to measurement as in many cases first year students are in the process of adapting to a new stage in their life, along with attempting to master many new subjects (Cottrell, 2008). This is reinforced by Johnston (2010) who highlights the many challenges being experienced by first year students and observes that “ entering first year is one of the most powerful elements of the university experience” (Johnston 2010, p4). The method of delivery generally favoured by lecturers on measurement modules focuses on traditional manual measurement techniques, which some may argue, contradicts current work practices. In industry, the widespread utilisation of computerised systems has to a great extent made the labour intensive manual processing of dimensions redundant. Many commentators within the Quantity Surveying profession question the efficacy of traditional lectures for students who will eventually be employed in a computerised environment. Blight (2000) investigates the merits and deficiencies of traditional lectures, and points out that “lecturing is the most common method when teaching adults, in spite of opportunities for innovation provided by changing technology.” (Blight 2000, p3).This paper sets out to establish the student’s perspective on teaching methods currently in usage on measurement modules, and their views on the relevance of learning traditional manual techniques. My underlying philosophy is in line with (Macfarlane 2004 p.7) “University lecturers are often involved in preparing students for the demands of professional life”. As my lectures deal with a practical technical discipline, there is a close relationship with industry. Using a quantitative methodology, I have compiled and analysed student’s views with regard to teaching on measurement modules, and it’s relevance to current practice in the Irish construction industry. My findings illustrate an overwhelming support amongst students for retention of traditional teaching methods, enhanced by better access to current measurement software

Intelligent aerial store & foreword packet repeater

A communication framework capable of rapid deployment and adaptive wireless support was designed and implemented using an unmanned aerial vehicle equipped with a 900 MHz, frequency- hopping transceiver configured as a store and forward packet repeater. Users with or without line of sight propagation between one another can automatically connect through the packet repeater and employ the aerial platform for extended data transfer. The airborne vehicle accommodates dynamic re-positioning in response to varying radio link conditions, thus supporting communication between highly mobile and/or line of sight-obstructed users even as the network topology evolves. Using open source and custom written software applications, as well as specially modified radio firmware, a command and data-logging environment was designed to monitor, control and initialize radio network conditions and vehicle platforms in real time. Careful real world evaluation of the developed system has demonstrated a robust platform capable of improvement to a user\u27s communication performance

The Use of Internships as a Work Placement Option on Quantity Surveying Courses in Light of the Current Economic Downturn in the Irish Construction Industry

This research examines the concept of internships as a Work Placement option on undergraduate Quantity Surveying courses in light of the economic climate that prevails in Ireland at present. The Irish Construction Industry has experienced unprecedented decline over the last six years, with reduced employment prospects as a result. Graduates on construction related courses are having difficulties sourcing employment, and many feel that they are disadvantaged if they have not experienced work placement as part of their undergraduate course. The benefits of work placement as a mode of learning have been well documented, however this study explores work placement on a specific Quantity Surveying course, within the context of a depressed economy. The views of Employers, Students, Lecturers, and Graduates are compiled and analysed to provide findings on how best to facilitate this mode of learning. This phenomenological study uses a research design which is interpretivist and qualitative in nature. The data was gathered through a series of semi-structured interviews conducted with the key stakeholders listed above. The primary concern was to compile rich and deep data from different perspectives on the work placement process. The design recognises the limitations of the research, and acknowledges that the findings are not exhaustive. This study suggests that Employers in the Construction Industry are still very positive towards employing work placement students despite the economic downturn. They advise that placement durations should be shorter than the traditional one year placement, with four to six months being more suitable. The findings suggest that Employers are not in favour of non-paid internship style placements. They advise that some form of remuneration is prudent, or students would not value the experience. Lecturers were also supportive of work placement, and again feel that payment must be included to avoid possible exploitation of students. Many Employers also acknowledge that work placement serves as a vetting arena for recruiting potential full time employees in the future. This study suggests that students and graduates are very supportive of work placement modules, whether paid or unpaid, and look towards employability after graduation as their overriding concern. The main conclusion is that there is a strong argument in favour of including work placement modules on undergraduate Quantity Surveying courses, despite the logistical challenges posed by a declining Construction Industry