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Forest owners, governments, and environmental organizations demand forest information for planning of forest operations, estimation of value, and for environmental monitoring. This information is collected using airborne and satellite remote sensing combined with field inventory of sample plots. Stem diameter is measured with calipers, which is labor-intensive. Terrestrial sensors could make the inventory faster, and more samples could be taken. Sensors mounted on forest harvesters could produce maps of the trees left after forest operations, or collect data for an operator support system. The first article describes a photogrammetric method using a multi-camera rig for estimation of stem diameter and position on field plots. Problematic light conditions reduced the usable amount of field plots. On adequate field plots, 76% of the trees were detected and positioned, and on 40% of the trees the diameters could be estimated. In the second article, the results from a mobile laser scanning project was improved by treating the data line-wise, and by using the intensity of the laser points as a quality value. The RMSE of the stem diameters was reduced from 24% to 14%, but the bias increased slightly from -1.9% to 2.3%. The edge points on the stems were identified as an error source since they were not found along the expected circle. The third article investigates this edge point problem by simulation of laser scanner/tree combinations. A relationship between the diameter error and the footprint size relative to the stem diameter was found. Commonly used mobile laser scanners were concluded to give a relative bias of 10% or more when estimating diameters using circle fit methods. In the fourth article, a panorama image of the intensities of a laser scanner point cloud was used to detect trees, with adequate results. The overall conclusions are that point clouds from the various sensors are useful for estimation of tree diameter and positions, but they have sensor-dependent properties that can introduce errors. These properties, and the precision requirement should be considered when the data acquisition is planned and the sensor is selected.

This study in contemporary history describes the transformation of the public sphere in Sweden during the period 1969-1999, and analyses the role of information technology and politics in the process. The overall aim of the study is to explain how, and why, the public sphere in Jürgen Habermas sense has deteriorated during a period of rapid technological and political change, when increasing attention has been given to information technology as a new tool for improving democracy and empowering citizens. Theoretical inspiration is drawn from two perspectives within the modern history of technology and sociology of technology; the LTS (Large Technical Systems) and STS (Science, Technology and Society) approaches, as well as from the regime theory concept within political science. This multidisciplinary framework provides the theoretical basis for the study, including terms as socio-technical systems, system builder, technification, interpretative flexibility, stabilization, closing and regime change. In addition, the analysis draws upon previous research in economic history, where focus often has been on the important role of institutions. The term path dependence is central in this tradition. The starting point for the study is the process of a mutual legitimization between citizens and political actors that traditionally has taken place within the public sphere. In return for citizens support and trust, political actors have granted format rights to the public space. Two aspects of this interdependence are addressed: Freedom of speech and citizen's access to public information, and their access to arenas where an exchange of political ideas and opinions is taking place. In the study, the former is a question of the legal system and the limits to freedom of speech in new medias such as the Internet, while the latter concerns citizen's technical means and possibilities to connect to electronic networks. Research interest is concentrated on the formal political system, focusing both actors and structural factors such as technological development, media convergence, ideological change and international integration in the transformation process. Four case studies of institutional changes during formative moments, within what is defined as the legal and the technical infrastructures, are conducted and represent the empirical base of the thesis. The case studies are centered on Swedish governmental commissions, on the government itself and on proceedings in the parliament, and concerns formation and transformation of computer law, as well as the deregulation and privatization of the technical infrastructure. In the latter process Televerket (Swedish Telecom) has been an influential promoter of competition and institutional separation between tele- and data communications, representing a major regime change in favour of market relations in the technical infrastructure. In the area of computer law, the Swedish regime dominated by SCB (Statistics Sweden) was incorporated into a joint European data protection regime, resulting in limitations of freedom of speech on the Internet. These regime changes have also transformed the role of the state, constituting a "net watchers state". Another important finding is that promotion of democracy and improvement of access to the public sphere, never was on the agenda in the political transformation processes studied, although a parallel discourse on democracy and information technology existed throughout the period studied.

Young people's view of nuclear power and democracy since the 1980s: attitude epidemics, path dependencies and technical-political cultural revolution. In the wake of the leftist wave, young people's criticism of the system has diminished, both in terms of criticism of the nuclear-based energy system and of the nature and workings of the political system. Baby-boomers (people born in the 1940s and '50s) in particular have changed their attitude and become less hostile to the establishment. But how did this change in attitudes occur? How has young people's view of technology and democracy changed during the past few decades? Based on data from the SOM Institute gathered between 1987 and 2005, this final report presents the results of one of the two studies conducted in the project "Towards activism or indifference? How Swedish young people view democracy and the environment, science and technology in an international and longitudinal perspective". First a theory and a method are proposed for analyzing what is called in this report "attitude epidemics", referring to the fact that attitudes spread like wildfire or epidemics, leading to what societal researchers call "path dependencies". Then age-versus-generation differences are studied, as well as a large number of other factors, with regard to attitudes to technology, nuclear power and democracy in particular, or the way democracy works in Sweden. Younger people are found to be the most critical of nuclear power, while they are most satisfied with democracy, even though gender, risk perceptions, party affiliation and political positioning are some of the factors that also influence these analyses on the individual level. The "epidemic effect" and path dependencies do not show their strength in these individual analyses, but all the more in the analysis of time series where the computer and IT revolution is found to be very strongly linked to the strong growth in acceptance of nuclear power. Using new communication technologies is somehow associated with a decline in hostility toward technology and nuclear power. But many cause-and-effect relationships in this attitudinal and technical-political "cultural revolution" still remain to be explored. ; I vänstervågens svall har ungdomens systemkritik avklingat, både i bemärkelsen kritik mot det kärnkraftsbaserade energisystemet och mot det politiska systemets väsen och funktionssätt. Främst 1940- och 1950-talisterna har ändrat inställning och blivit mindre systemfientliga. Men hur gick denna förändring i attityder egentligen till? Hur har synen på teknik och demokrati bland ungdomar förändrats senaste årtiondena? Med användning av SOM-institutets data 1987–2005 presenterar denna slutrapport resultat från en av de två delstudierna inom projektet "Mot aktivism eller ointresse? Svenska ungdomars syn på demokrati och teknologi i ett internationellt och longitudinellt perspektiv". Först föreslås teori och metod för att analysera det som i denna rapport kallas "attitydepidemier", att attityder sprider sig lavinartat, och genom dem etablering av vad samhällsforskare kallar "stigberoenden". Därefter studeras ålders- kontra generationsskillnader, liksom ett stort antal andra faktorer, med avseende på attityder till framför allt tekniken kärnkraft och demokrati eller demokratins funktionssätt i Sverige. Yngre visar sig vara de mest kritiska mot kärnkraften men de mest nöjda med demokratin, även om kön, riskuppfattningar, partianhängarskap och politisk positionering är några av de faktorer som också spelar roll i dessa analyser på individnivå. "Epidemieffekten" och stigberoenden visar inte sin styrka i dessa individanalyser, men desto mer i analysen av tidsserier där dator- och IT-revolutionen visar sig mycket starkt förbunden med den starka tillväxten i kärnkraftsacceptans. Att använda nya kommunikationstekniker hänger på något sätt samman med minskning av teknikfientlighet även till kärnkraften. Men många orsakssamband i denna attitydmässiga och teknisk-politiska "kulturrevolution" är fortfarande outforskade. ; "Mot aktivism eller ointresse? Svenska ungdomars syn på demokrati och teknologi i ett internationellt och longitudinellt perspektiv"