Purpose Big Data introduces high amounts and new forms of structured, unstructured and semi-structured data into the field of accounting and this requires alternative data management and reporting methods. Generating insights from these new data sources highlight the need for different and interactive forms of visualization in the field of visual analytics. Nonetheless, a considerable gap between the recommendations in research and the current usage in practice is evident. In order to understand and overcome this gap, a detailed analysis of the status quo as well as the identification of potential barriers for adoption is vital. The paper aims to discuss this issue. Design/methodology/approach A survey with 145 business accountants from Austrian companies from a wide array of business sectors and all hierarchy levels has been conducted. The survey is targeted toward the purpose of this study: identifying barriers, clustered as human-related and technological-related, as well as investigating current practice with respect to interactive visualization use for Big Data. Findings The lack of knowledge and experience regarding new visualization types and interaction techniques and the sole focus on Microsoft Excel as a visualization tool can be identified as the main barriers, while the use of multiple data sources and the gradual implementation of further software tools determine the first drivers of adoption. Research limitations/implications Due to the data collection with a standardized survey, there was no possibility of dealing with participants individually, which could lead to a misinterpretation of the given answers. Further, the sample population is Austrian, which might cause issues in terms of generalizing results to other geographical or cultural heritages. Practical implications The study shows that those knowledgeable and familiar with interactive Big Data visualizations indicate high perceived ease of use. It is, therefore, necessary to offer sufficient training as well as user-centered visualizations and technological support to further increase usage within the accounting profession. Originality/value A lot of research has been dedicated to the introduction of novel forms of interactive visualizations. However, little focus has been laid on the impact of these new tools for Big Data from a practitioner’s perspective and their needs.

The objective of this paper is to analyse and present the latest results obtained for free-space optics (FSO) within the EU COST Action IC-0802 and within the European Space Agency (ESA) contract. First, the FSO technology is briefly discussed and some performance evaluation criteria for FSO are provided. Some optical signal propagation experiments through the atmosphere (including the recent investigations in airborne and satellite application for FSO) are also shown. In the main part, considerations on suitability of different optical wavelengths are brought into question. The wavelength selection is dependent on the atmospheric effects and on the availability of receiver and transmitter components. Discussion on the available receiver(s) and transmitter(s) includes the focus on advantages and mainly the costs of the different systems. In the final part, we examine the latest practical results (carried out within the COST Action IC-0802) on modelling of the FSO channel under fog conditions and other atmospheric effects. Additionally, recent results, showing major performance improvement, based on the hybrid system and specific modulation and coding schemes are presented. Keywords: Free-space optics, broadband wireless, network architectures, last mile access, reliability and availability. INTRODUCTIONFSO communication systems consist of an optical transmitter which is a laser source or a LED, a modulator and a telescope. The receiver consists of a detector, a decoder and a telescope to collect the optical signal. The optical signal propagates through the free space which acts as the link channel. Interest in FSO continues to grow mainly for two reasons: first identification as an attractive alternative or a complementary to existing microwave (millimetre wave (MMW)) and the radio frequency (RF) communication links, and secondly being a broadband wireless solution for the "Last Mile" connectivity in metropolitan networks, point-to-point and point-tomultipoint link configurations. Last couple of years have witnessed a growing demand for higher data rates and wider bandwidths from the end user to manipulate multimedia information. This development will continue in the next couple of decades being a challenge for the future Next Generation Networks. So the end-user will need higher data rates and access to the fully available bandwidth within the backbone delivered to the home. Currently FSO is being researched for applications involving ground-to-ground (short and long distance terrestrial links), satellite uplink/downlink, inter-satellite, deep space probes to ground, and ground-to-air/air-toground terminal (UAV, HAP etc.) [1]. This has resulted in some successful experiments such as SILEX (a link between Artemis and SPOT-4). The prime advantages of FSO are: higher data rates exceeding easily 100 bit/s using wavelength division multiplexing (WDM) techniques, security aspects, EMC/EMI immunity and frequency regulation issues. Additionally, small terminal size, light weight, minimal aperture sizes and low ...

A sizable part of HCI research on cross-device interaction is driven by the vision of users conducting complex knowledge work seamlessly across multiple mobile devices. This is based on the Weiserian assumption that people will be inclined to distribute their work across multiple "pads" if such are available. We observed that this is not the reality today, even when devices were in abundance. We present a study with 24 participants in 12 dyads completing a collaborative visualization task with up to six tablets. They could choose between three different visualization types to answer questions about economic data. Tasks were designed to afford simultaneous use of tablets, either with linked or independent views. We found that users typically utilized only one tablet per user. A quantitative and qualitative analysis revealed a "legacy bias" that introduced barriers for using more tablets and reduced the overall benefit of multi-device visualization.

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SUMMARY Increasing demand in data-traffic has been addressed over the last few years. It is expected that the data-traffic will present the significant part of the total backbone traffic. Accordingly, much more transmission systems will be required to support this growth. A free space optic (FSO) communication is the greatest promising technology supporting high-speed and high-capacity transport networks. It can support multi Gbit/s for few kilometers transmission distance. The benefits of an FSO system are widespread, low cost, flexibility, immunity to electromagnetic field, fast deployment, security, etc. However, it suffers from some drawbacks, which limit the deployment of FSO links. The main drawback in FSO is the degradation in the signal quality because of atmospheric channel impairments. In addition, it is high sensitive for illumination noise coming from external sources such as sun and lighting systems. It is more benefit that FSO and mmWave are operating as a complementary solution that is known as hybrid FSO/mmWave links. Whereas the mmWave is susceptible to heavy rain conditions and oxygen absorption, while fog has no particular effect. This paper will help to better understand the FSO and mmWave technologies and applications operating under various atmospheric conditions. Furthermore, in order to improve the system performance and availability, several modulation schemes will be discussed. In addition to, the hybrid FSO/mmWave with different diversity combining techniques are presented.