Patient exposure monitoring and radiation qualities in two-dimensional digital x-ray imaging

The methods for estimating patient exposure in x-ray imaging are based on the measurement of radiation incident on the patient. In digital imaging, the useful dose range of the detector is large and excessive doses may remain undetected. Therefore, real-time monitoring of radiation exposure is important. According to international recommendations, the measurement uncertainty should be lower than 7% (confidence level 95%). The kerma-area product (KAP) is a measurement quantity used for monitoring patient exposure to radiation. A field KAP meter is typically attached to an x-ray device, and it is important to recognize the effect of this measurement geometry on the response of the meter. In a tandem calibration method, introduced in this study, a field KAP meter is used in its clinical position and calibration is performed with a reference KAP meter. This method provides a practical way to calibrate field KAP meters. However, the reference KAP meters require comprehensive calibration. In the calibration laboratory it is recommended to use standard radiation qualities. These qualities do not entirely correspond to the large range of clinical radiation qualities. In this work, the energy dependence of the response of different KAP meter types was examined. According to our findings, the recommended accuracy in KAP measurements is difficult to achieve with conventional KAP meters because of their strong energy dependence. The energy dependence of the response of a novel large KAP meter was found out to be much lower than with a conventional KAP meter. The accuracy of the tandem method can be improved by using this meter type as a reference meter. A KAP meter cannot be used to determine the radiation exposure of patients in mammography, in which part of the radiation beam is always aimed directly at the detector without attenuation produced by the tissue. This work assessed whether pixel values from this detector area could be used to monitor the radiation beam incident on the patient. The results were congruent with the tube output calculation, which is the method generally used for this purpose. The recommended accuracy can be achieved with the studied method. New optimization of radiation qualities and dose level is needed when other detector types are introduced. In this work, the optimal selections were examined with one direct digital detector type. For this device, the use of radiation qualities with higher energies was recommended and appropriate image quality was achieved by increasing the low dose level of the system.

Mapping sociocultural controversies across digital media platforms: One week of #gamergate on Twitter, YouTube, and Tumblr

Social media play a prominent role in mediating issues of public concern, not only providing the stage on which public debates play out but also shaping their topics and dynamics. Building on and extending existing approaches to both issue mapping and social media analysis, this article explores ways of accounting for popular media practices and the special case of ‘born digital’ sociocultural controversies. We present a case study of the GamerGate controversy with a particular focus on a spike in activity associated with a 2015 Law and Order: SVU episode about gender-based violence and harassment in games culture that was widely interpreted as being based on events associated with GamerGate. The case highlights the importance and challenges of accounting for the cultural dynamics of digital media within and across platforms.

Towards a typology of hashtag publics: A large-scale comparative study of user engagement across trending topics

Twitter’s hashtag functionality is now used for a very wide variety of purposes, from covering crises and other breaking news events through gathering an instant community around shared media texts (such as sporting events and TV broadcasts) to signalling emotive states from amusement to despair. These divergent uses of the hashtag are increasingly recognised in the literature, with attention paid especially to the ability for hashtags to facilitate the creation of ad hoc or hashtag publics. A more comprehensive understanding of these different uses of hashtags has yet to be developed, however. Previous research has explored the potential for a systematic analysis of the quantitative metrics that could be generated from processing a series of hashtag datasets. Such research found, for example, that crisis-related hashtags exhibited a significantly larger incidence of retweets and tweets containing URLs than hashtags relating to televised events, and on this basis hypothesised that the information-seeking and -sharing behaviours of Twitter users in such different contexts were substantially divergent. This article updates such study and their methodology by examining the communicative metrics of a considerably larger and more diverse number of hashtag datasets, compiled over the past five years. This provides an opportunity both to confirm earlier findings, as well as to explore whether hashtag use practices may have shifted subsequently as Twitter’s userbase has developed further; it also enables the identification of further hashtag types beyond the “crisis” and “mainstream media event” types outlined to date. The article also explores the presence of such patterns beyond recognised hashtags, by incorporating an analysis of a number of keyword-based datasets. This large-scale, comparative approach contributes towards the establishment of a more comprehensive typology of hashtags and their publics, and the metrics it describes will also be able to be used to classify new hashtags emerging in the future. In turn, this may enable researchers to develop systems for automatically distinguishing newly trending topics into a number of event types, which may be useful for example for the automatic detection of acute crises and other breaking news events.

Book Review: "Engin Isin and Evelyn Ruppert, Being Digital Citizens. London: Rowman & Littlefield, 2015"

The concept of digital citizenship has become increasingly important to our understanding of the relationship between media and political action, and the possibilities for democratization, decentralization, and diversification of power offered by the Internet. In the era of the digitalization of just about everything, citizenship and its related concepts are in processes of technology-driven transformation, with important implications for the global future of democratic culture. Isin and Ruppert’s book is a timely engagement with these questions, and with the emerging notion of the “digital subject.”

Slogans of Change : Three Outlooks on Finnish Television

The study Slogans of Change. Three Outlooks on Finnish Television Contents is concerned with alleged changes of television contents during the 1990s and 2000s, such as dumbing down, tabloidisation, entertainisation , and the like. Specifically, the focus is on the ways these changes might manifest in Finnish television. The aim of the study has been threefold: 1. To operationalise public and academic discussions about changes via specific slogans emerging from the debates; 2. Consequently, to study the slogans empirically and reflect on the findings with earlier research, including studies on institutional and audience-related aspects; 3. Finally, to suggest what the findings might mean regarding discussions about television s role, and what kinds of slogans or concepts might best serve future discussions and research. The empirical outlooks presented in this study offer analyses with three different sets of opposing slogans of change. The outlooks also follow three different traditions of the study of television. The first outlook focuses on quantity, as it gives a longitudinal (1993-2004), macro-level view on programme structures. The methodological approach is derived from media economic and policy studies. The claims that frame the analysis are convergence versus diversification of programme structures. The second outlook provides quantitative and qualitative views on the characteristics and quality  the term signifying essence as well as worth  of Finnish television journalism during sample weeks from the years 2002 and 2003. This outlook follows the traditions of quantitative content analysis found in journalism studies coupled with descriptive qualitative content analyses. The slogans reflected in this section are the lightening or widening of journalism. The third outlook narrows down the material and focuses at a micro-level on form; that is, communicative conventions in a small array of selected programmes in 1993, 2000 and during 2002-2004. The analyses have been inspired by the method of conversation analysis of verbal interaction, and coupled with qualitative close readings, with the focus of different communicative situations in the programmes. The catchphrases employed in this part are emotainment versus democratainment, coupled with more specific claims of discursive hybridisation and conversationalisation. The findings depict that, empirically, changes in Finnish television contents are not clear linear trends and cannot easily be moulded into neat slogans. The quantitative outlook on programme output during 1993-2004 depicts a tendency towards differentiation of channels, paving the way for the multi-channel digital system. The change in programme structures, however, is not dramatic on the level of total output. The second outlook suggests that the dualistic concepts, such as the pair information-entertainment, are not sufficient in understanding the array and changes of programmes that could be called journalism. The outlook on communicative conventions highlights hybridisation in the manner of television talk and its relation to broader debates on contents. Despite the three dissimilar empirical approaches, unifying aspects emerge. The outlooks suggest, albeit in different ways, tendencies toward distinction and polarisation. This study proposes that in order to facilitate a more nuanced understanding of the changes in television contents, dualistic slogans should be replaced with a multi-dimensional understanding of the concept of diversity.

Leading Digital Transformation: Building Technology and Information Governance Capability in Boards of Directors and the C-Suite

Information and technology and its use in organisation transformation presents unprecedented opportunities and risks. Increasingly, the Governance of Enterprise Information and Technology (GEIT) competency in the board room and executive is needed. Whether your organization is small or large, public, private or not for profit or whether your industry is not considered high-tech, IT is impacting your sector – no exceptions. But there is a skill shortage in boards: GEIT capability is concerningly low. This capability is urgently needed across the board, including those directors who come from finance, legal, marketing, operations and HR backgrounds. Digital disruption also affects all occupations. Putting in place a vision will help ensure emergency responses will meet technology-related duty of care responsibilities. When GEIT-related forward thinking and planning is carried out at the same time that you put your business strategy and plan in place, your organization has a significantly increased chance of not only surviving, but thriving into the future. Those organizations that don’t build GEIT capability risk joining the growing list of once-leading firms left behind in the digital ‘cloud of smoke’. Those organizations that do will be better placed to reap the benefits and hedge against the risks of a digital world. This chapter provides actionable, research-based considerations and processes for boards to use, to build awareness, knowledge and skills in governing technology-related organization strategy, risk and value creation.

Teille on syntynyt Vapahtaja : Joulun kirkollinen sanoma, jouluperinteet ja perheyhteisö Yleisradion TV-jumalanpalvelusten joulusaarnoissa 1985 - 2009

Yleisradion jouluaamuna lähettämä TV-jumalanpalvelus kerää vuosittain enemmän katsojia kuin kaikissa Suomen kirkoissa yhteensä käy ihmisiä samana aamuna. TV:n joulusaarnalla onkin merkitystä siihen, miten ihmiset mieltävät kirkon sanoman joulusta. Tämän tutkimuksen tarkoituksena oli tarkastella TV-jumalanpalveluksen joulusaarnan muutosta vuosien 1985 ja 2009 välisenä aikana sekä toteutuksen että sisällön näkökulmasta. Pääasiallisena tutkimuskohteena oli sisällön muutos (1) kirkollisen sanoman, (2) jouluperinteen ja -tunnelman sekä (3) perheyhteisön kuvausten suhteen. Teemat valittiin aiempien saarnatutkimusten sekä kolmen joulusaarnan alustavan analyysin perusteella. Tutkimusaineiston muodostivat kaikki Kirkon tiedotuskeskuksen arkistosta löytyneet joulusaarnat, joissa oli sekä kuva että ääni. Aineisto koostui 20 saarnasta, jotka litteroitiin ja analysoitiin. Lisäksi nauhoitettiin kaksi taustahaastattelua. Tutkimusmetodina käytettiin kvalitatiivista metodia, teoriaohjaavaa sisällönanalyysiä, jonka tulokset luokiteltiin ja kvantifioitiin. Sisällönanalyysin tuloksia havainnollistettiin taulukoiden ja graafisten kuvioiden avulla. Muutoksen havaitsemisen apuna käytettiin summamuuttujia neljän tarkastelujakson osalta, vuosilta 1985-1991, 1992-1996, 2000-2004 ja 2005-2009. Saarnojen toteutuksen suhteen todettiin, että joulusaarnat lyhentyivät hieman tutkimusjakson aikana. Saarnan kuvitus muuttui vuodesta 2003 lähtien niukemmaksi, jotta katsojat voisivat keskittyä paremmin saarnan sisältöön. Saarnaajien oheisviestintä oli vähäistä, ja useimmiten saarnaajilla oli vain yksi ilme ja erittäin vähän eleitä. Kertomusten käyttö lisääntyi saarnoissa selvästi, ja vuosina 2005-2009 sekä jouluevankeliumia että muita raamatunkohtia havainnollistettiin kertomusten avulla aiempaa enemmän. Yleisin saarnoissa lainattu raamatunkohta oli enkelien julistus ”Teille on syntynyt Vapahtaja” . Jeesukseen viittaavat nimitykset muuttuivat tutkimusjakson aikana mielenkiintoisella tavalla. Nimike Jeesus oli yleisin nimike vuodesta 1985 vuoteen 2004. Sen jälkeen yleisimmäksi nimikkeeksi nousi lapsi, ja joulusaarnoissa käytettiin runsaasti myös muita yleiskieleen kuuluvia nimikkeitä, jotka tiivistettiin muotoon avuton lapsi/vastasyntynyt. Perinteisiä kristillisiä nimikkeitä, kuten Herra, Kristus ja seimen lapsi, ei käytetty vuosina 2005-2009 lainkaan. Tämä herätti kysymyksen siitä, onko joulun sanoma maallistunut. Oletus ei saanut tukea kirkolliseen sanomaan liittyvien teemojen tarkastelusta. Vaikka syyllisyyden kuvaukset vähentyivät, rakkauden merkitys korostui tutkimusjakson loppua kohden, ja myös elämän tarkoitukseen liittyvät asiat mainittiin 2000-luvulla useammin kuin aiemmin. Erityisesti inkarnaation Jumalan ihmiseksi tulemisen kuvaukset lisääntyivät, joten joulun kirkollinen ydinsanoma oli entistä selkeämmin esillä. Jouluperinteen kuvausten suhteen ei havaittu muutosta vuosikymmenten aikana. Tunnelmaa kuvattiin tutkimusjakson alussa rauhan ja ihmeen käsittein, mutta lopussa valo korostui. Perheyhteisön kuvaukset olivat hyvin esillä, sillä lapset mainittiin joka toisessa ja perhe joka kolmannessa saarnassa. Lapset mainittiin vuosikymmenten kuluessa entistä useammin, ja myös yksinäisyyden kuvaukset lisääntyivät. Seurakunta mainittiin joulusaarnoissa hyvin harvoin, mikä sai pohtimaan seurakunnan roolia yhteisöllisyyden kannalta. Tutkimuksen johtopäätöksenä todettiin, että suomalaisen nyky-yhteiskunnan maallistumiskehitys ei näy TV:n joulusaarnoissa 1985-2009.

An Inexpensive Digital Network Analyzer

Frequency response analysis is critical in understanding the steady and transient state behavior of any electrical network. Network analyzeror frequency response analyzer is used to determine the frequency response of an electrical network. This paper deals with the design of an inexpensive digitally controlled Network Analyzer. The frequency range of the network analyzer is from 10Hz to 50kHz (suitable range for system studies on most power electronics apparatus). It is composed of a microcontroller (as central processing unit) and a personal computer (as analyzer and display). The communication between the microcontroller and personal computer is established through one of the USB ports. The testing and evaluation of the analyzer is done with RC, RLC and multi-resonant circuits. The design steps, basis of analysis, experimental results, limitation in bandwidth and possible techniques for improvement in performances are presented.