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The spatio-temporal changes of rangelands in the European Mediterranean are analysed with remote sensing and GIS-based methods, referring to an example of two mountain ranges in central Crete, Greece. The focus is to monitor and assess land degradation and its potential correlation with ecological and socio-economic boundary conditions. Particular attention is paid to the unique European Mediterranean setting and the Greek integration within the European Union. After a geometric correction of the satellite data, a radiometric pre-processing chain is employed to calculate reflectance values via a DEM-based atmospheric correction. The computation of pixel-wise soil and vegetation fractions is based on a spectral unmixing approach. A subsequent time-series analysis reveals spatially explicit trends, mean vegetation cover and phenological variability. Results do not only exhibit significant differences between the two test sites, but also within the respective regions. In both mountain ranges there extended areas with degrading vegetation patterns are revealed. However, along the Southern Cretan coast those processes are bound to a much lower base level of vegetation cover. Beyond trends and mean vegetation abundance, the phenological variability is another important figure which is employed to characterise plant communities from space. Moreover, a satellite-based map of soil development proves the correspondence between soil and vegetation degradation processes. Vegetation cover and change are then analysed with regard to aspect, slope, elevation and geological substrate to allow for a comparison of degradation processes and natural boundary conditions. In a second step, the analyses are extended to find interrelationships with socio-economic determinants. Based on these results the degradation risk for the grazing habitats of central Crete is assessed in differentiated ways. We neither encounter the scenario of irreversible degraded rangelands, nor a cultural landscape in an equilibrium under intense human influence.
Die ubiquitäre Verbreitung von Computern hat dazu geführt, daß immer mehr Arbeitsabläufe durch Software unterstützt werden. Mit der ISO 13407 liegt eine Normierung vor, die den Entwickler von Software dazu anhält, die Anforderungen der Benutzer an sein Produkt zu berücksichtigen. In den letzten Jahrzehnten hat sich die objektorientierte Softwareentwicklung als gängige Entwicklungsmethode durchgesetzt, die durch eine Kapselung von Methoden und Daten zu Objekten und durch ein iteratives Vorgehen geprägt ist. Dieses Vorgehen und die Anforderungen der Norm rücken die Perspektive des Benutzers ins Zentrum des Interesses des Softwareentwicklers. Damit die Anforderungen der Nutzer berücksichtigt werden können, fehlt ein Werkzeug, mit dem die Sicht auf den Arbeitsvorgang effizient, vollständig und zutreffend erhoben werden kann. In der Dissertationsschrift werden zuerst die Bedürfnisse der Beteiligten am Softwareentwicklungsprozeß, nämlich die der objektorientierten Entwickler einerseits und der Benutzer andererseits, aus den gängigen theoretischen Konzepten abgeleitet. Dann wird das Instrument zur Vorgangsanalyse (IVA) vorgestellt und die Konstruktion anhand der Bedürfnissen der Beteiligten erläutert. Beim Instrument zur Vorgangsanalyse handelt es sich um eine Kombination aus strukturierten Interview und Strukturlegetechnik, die die Aufgabe des Befragten und den umgebenden Arbeitsvorgang mit Hilfe eines einfachen Paper-Pencil- Verfahrens visualisiert. Im Anschluß an die Vorstellung des Verfahrens werden anhand der Gütekriterien für qualitative Verfahren Prüfkriterien abgeleitet, um das Instrument zu validieren. Es werden vier unterschiedliche Untersuchungen mit verschiedenen Herangehensweisen an die Klärung der Prüfkriterien vorgestellt. Die Ergebnisse dieser Überprüfung belegen, daß das Instrument zur Vorgangsanalyse geeignet ist, im Prozeß der objektorientierten Softwareentwicklung die Zusammenarbeit zwischen den Entwicklern und den Benutzern zu unterstützen.
Soziale Dienste in Taiwan
(2001)
Soziale Dienste sind Ausdruck einer wichtigen Form von Helfen innerhalb einer Gesellschaft. Die Entfaltungsmöglichkeit und der Entwicklungsgrad der sozialen Dienste sind nicht unabhängig von spezifischen räumlichen und zeitlichen Hintergründen, und sie werden auch von den gesamtgesellschaftlichen Bedingungen (z. B. politisch-rechtlichen, wirtschaftlichen, soziokulturellen Faktoren) beeinflusst. Um die Besonderheiten der sozialen Dienste innerhalb der taiwanesischen Gesellschaft zu verdeutlichen, sollen die oben erwähnten Hintergründe und Bedingungen analysiert und dargestellt werden. In Taiwan erfolgte die Entwicklung wohlfahrtsstaatlicher Institutionen und Programmen im Vergleich zu Westeuropa zeitlich schnellen. Dabei ist ein Zusammenhang zu sehen mit der gezielt vorangetriebenen wirtschaftlichen Modernisierung. Dies gilt auch für die Demokratisierungsbewegung, die gleichzeitig auf Druck von unten wie auf Initiative von oben ausging. Sozialpolitische Maßnahmen konnten nur dann Erfolg haben, wenn Systemvertrauen gewonnen werden konnte. Dies erwies sich in Taiwan als notwendig, weil in der taiwanesischen Gesellschaft traditionell nur eine Vertrauensbasis innerhalb überschaubarer Personenkreise bestand. In dieser Arbeit zeigte es sich, dass entgegen einer häufig geäußerten Behauptung von der Überlegenheit "asiatischer Werte" bestimmte kulturelle Muster (z. B. Drei-Generationen-Zusammenleben) angesichts eines rasanten sozialen Wandels anpassungshemmend wirken werden können. Es handelt sich im vorliegenden Fall um die innerfamiliäre Solidarität bei der Versorgung älterer Angehöriger. Wenn dieses Leitbild weiterhin Orientierung geben soll, müssen in der sich verändernden Gesellschaft unterstützende Maßnahmen entwickelt werden. Ohne entsprechende Innovationen auf diesem Gebiet und in verwandten Bereichen gerät der "Confucian welfare state" in Gefahr.
Wastewater treatment is of great financial concern in many states of Germany. In the rural areas of the Saarland (German state at the border to Luxembourg and France) investments for wastewater treatments in the next years will mount up to 400 mio. €. Nevertheless, decision makers are still left with the question, if these investments result in an effective and sustainable water treatment. To answer this question, the ministry of environment, related authorities and the University of the Saarland (Geographical Institute) started a Project to investigate seven small headwater catchments with predominantly Triassic series of Muschelkalk. Aims of this study were the following: (i) the description of the spatial variability of water chemistry upstream and downstream of small villages (in these villages only mechanically treated waste water is discharged into the brooks), (ii) calculation of nutrient loads of differently managed catchments (predominantly woodland, meadows or fields) and (iii) the relative importance of non-point pollution sources to point pollution sources. Results indicated that spatial variability of nitrate concentration during base-flow conditions was quite similar in intensively used agricultural areas. Nitrogen fluxes were predominantly controlled hydrologically. The nitrogen load (kg N per ha) from non-point pollution sources amounts from 32.5 to 43 kg N / ha * a in intensively used agricultural areas. This load, forecast to one square-km, is equal to the N-load of 800 " 1000 population equivalents. Thus, non-point pollution sources are a major part of the overall nitrogen pollution in the rural areas. The results are important criterias for the sewage disposal plan of the Saarland (disposal plans are obligate according to German water law) and can serve as a first part of a river basin management according to the European Water Framework Directive. To lower non-point N-pollution changes in agricultural management practices are necessary.
This dissertation develops a rationale of how to use fossil data in solving biogeographical and ecological problems. It is argued that large amounts of fossil data of high quality can be used to document the evolutionary processes (the origin, development, formation and dynamics) of Arealsystems, which can be divided into six stages in North America: the Refugium Stage (before 15,000 years ago: > 15 ka), the Dispersal Stage (from 8,000 to 15,000 years ago: 8.0 - 15 ka), the Developing Stage (from 3,000 to 8,000 years ago: 3.0 - 8.0 ka), the Transitional Stage (from 1,000 to 3,000 years ago: 1 - 3 ka), the Primitive Stage (from 5,00 to 1,000 years ago: 0.5 - 1 ka) and the Human Disturbing Stage (during the last 500 years: < 0.5 ka). The division into these six stages is based on geostatistical analysis of the FAUNMAP database that contains 43,851 fossil records collected from 1860 to 1994 in North America. Fossil data are one of the best materials to test the glacial refugia theory. Glacial refugia represent areas where flora and fauna were preserved during the glacial period, characterized by richness in species and endemic species at present. This means that these (endemic) species should have distributed purely or primarily in these areas during the glacial period. The refugia can therefore be identified by fossil records of that period. If it is not the case, the richness in (endemic) species may not be the result of the glacial refugia. By exploring where mammals lived during the Refugium Stage (> 15 ka), seven refugia in North America can be identified: the California Refugium, the Mexico Refugium, the Florida Refugium, the Appalachia Refugium, the Great Basin Refugium, the Rocky Mountain Refugium and the Great Lake Refugium. The first five refugia coincide well with De Lattin- dispersal centers recognized by biogeographical methods using data on modern distributions. The individuals of a species are not evenly distributed over its Arealsystem. Brown- Hot Spots Model shows that in most cases there is an enormous variation in abundance within an areal of a species: In a census, zero or only a very few individuals occur at most sample locations, but tens or hundreds are found at a few sample sites. Locations where only a few individuals can be sampled in a survey are called "cool spots", and sites where tens or hundreds of individuals can be observed in a survey are called "hot spots". Many areas within the areal are uninhabited, which are called "holes". This model has direct implications for analyzing fossil data: Hot spots have a much higher local population density than cool spots. The chances to discover fossil individuals of a species are much higher in sediments located in a "hot spot" area than in a "cool spot" area. Therefore much higher MNIs (Minimum Number of Individuals) of the species should be found in fossil localities located in the hot spot than in the cool spot area. There are only a few hot spots but many cool spots within an areal of a single hypothetical species, consequently only a few fossil sites can provide with much high MNIs, whereas most other sites can only provide with very low MNIs. This prediction has been proved to be true by analysis of 70 species in FAUMAP containing over 100 fossil records. The temporal and spatial variation in abundance can be reconstructed from the temporospatial distribution of the MNIs of a species over its Arealsystem. Areas with no fossil records from the last thousands of years may be holes, and sites with much higher MNIs may be hot spots, while locations with low MNIs may be cool spots. Although the hot spots of many species can remain unchanged in an area over thousands of years, our study shows that a large shift of hot spots occurred mainly around 1,500-1,000 years ago. There are three directions of movement: from the west side to the east side of the Rockies, from the East of the USA to the east side of the Rockies and from the west side of the Rockies to the Southwest of the USA. The first two directions of shift are called Lewis and Clark- pattern, which can be verified with the observations mad by Lewis and Clark during their expedition in 1805-1806. The historical process of this pattern may well explain the 200-year-old puzzle why big game then abundant on the east side were rare on the west side of the Rocky Mountains noted by modern ecologists and biogeographers. The third direction of shift is called Bayham- pattern. This pattern can be tested by the model of Late Holocene resource intensification first described by Frank E. Bayham. The historical process creating the Bayham pattern will challenge the classic explanation of the Late Holocene resource intensification. An environmental change model has been proposed to account for the shift of hot spots. Implications of glacial refugia and hot spots areas for wildlife management and effective conservation are discussed. Suggestions for paleontologists and zooarchaeologists regarding how to provide more valuable information in their future excavation and research for other disciplines are given.
Spatial Queues
(2000)
In the present thesis, a theoretical framework for the analysis of spatial queues is developed. Spatial queues are a generalization of the classical concept of queues as they provide the possibility of assigning properties to the users. These properties may influence the queueing process, but may also be of interest for themselves. As a field of application, mobile communication networks are modeled by spatial queues in order to demonstrate the advantage of including user properties into the queueing model. In this application, the property of main interest is the user's position in the network. After a short introduction, the second chapter contains an examination of the class of Markov-additive jump processes, including expressions for the transition probabilities and the expectation as well as laws of large numbers. Chapter 3 contains the definition and analysis of the central concept of spatial Markovian arrival processes (shortly: SMAPs) as a special case of Markov-additive jump processes, but also as a natural generalization from the well-known concept of BMAPs. In chapters 4 and 5, SMAPs serve as arrival streams for the analyzed periodic SMAP/M/c/c and SMAP/G/infinity queues, respectively. These types of queues find application as models or planning tools for mobile communication networks. The analysis of these queues involves new methods such that even for the special cases of BMAP inputs (i.e. non-spatial queues) new results are obtained. In chapter 6, a procedure for statistical parameter estimation is proposed along with its numerical results. The thesis is concluded by an appendix which collects necessary results from the theories of Markov jump processes and stochastic point fields. For special classes of Markov jump processes, new results have been obtained, too.
Die vorliegende Arbeit beschäftigt sich mit dem Problem, daß Internet-Inhalte weltweit als strafbare Kommunikationsdelikte angesehen werden können. Die Warnungen vor Neonazis, die aus dem Ausland agieren, werden immer eindringlicher; gleichzeitig fürchten sich deutsche Anbieter vor ausländischen Strafverfolgungsbehörden. Ob diesen Entwicklungen aber durch eine internationale Lösung erfolgreich entgegengewirkt werden kann, erscheint fraglich. Der Autor untersucht daher die Strafbarkeit von Internet-Inhalten im weltweiten Kontext. Die bisherigen Bemühungen um eine internationale Lösung werden dargestellt und ihre Erfolgsaussichten überprüft. Dabei zeigt sich, daß nationale Ansätze nicht vorschnell übergangen werden sollten.
An indignation control training has been developed and tested for it's effectiveness. The training was based upon a cognitive model of emotions. One's own cognitions in emotional situations are often considered to be "assertorically" true. Therefore it was tested, whether the emotion could be controlled by means of reflecting about one's own assertoric judgements and considering alternative interpretations of the current situation. The cognitive training was compared in terms of effectiveness to a relaxation training. Participants were randomly distributed to the experimental conditions: cognitive training, relaxation training and control group. Six training sessions à 90 min. - one per week- were conducted. Pre- post and follow-up-test after 3 month were undertaken. As dependent variables the following measures were used: Participants reported a personal indignation encounter and indicated their reactions to imaginal situations. Additionally a real provocation was realised. The data analysis was based upon a group of 72 persons. The cognitive training proved to be more effective in reducing indignation compared to the control group. Especially for behavioural measures the cognitive training was also superior compared to the relaxation approach. Taken together for the cognitive training group indignation in the own situation as well as in imaginal situations was reduced. Also perspective taking could be improved as well as destructive reactions in imaginal situations were reduced. After the real provocation less physiological arousal was reported as well as less negative reactions observed. Almost all effects remained stable over the 3 month follow-up period. The results clearly demonstrate the effectiveness of the new method. This new approach is also relevant for psychological interventions: A more precise control of emotion is possible because the training is based upon the specific cognitive components of the emotion. As a consequence, clients on their own are able to question their interpretation of a situation based upon each single cognition.
Die Dissertation beschäftigt sich mit der Frage, inwieweit und unter welchen Bedingungen psychophysiologische Maße gewinnbringend zur empirischen Prüfung physiologisch orientierter Persönlichkeitstheorien genutzt werden können. Am Beispiel des Extraversionsmodells von Brebner & Cooper (1985), das mit Hilfe ereigniskorrelierter Hirnrindenpotentiale (EKP) empirisch geprüft wurde, wird deutlich herausgearbeitet, mit welchen Herausforderungen sich eine solche Forschung konfrontiert sieht: die konsequente und streng theoriegeleitete Verknüpfung psychologischer Konzepte mit psychophysiologischen Maßen, die sorgfältige Berücksichtigung der funktionalen Bedeutung und der komplexen auslösenden Bedingungen der elektrophysiologischen Parametern im Kontext des gewählten Paradigmas sowie die umfassende Kontrolle experimenteller und situationsspezifischer Rahmenbedingung. Das Brebner-Cooper-Modell führt Verhaltensunterschiede zwischen Extravertierten und Introvertierten auf differentiell wirksame exzitatorische und inhibitorische Prozesse zurück, die im Zusammenhang mit der Analyse von Reizen (Reizanalyse) und der Vorbereitung von Reaktionen (Reaktionsorganisation) in einer spezifischen Situation stehen. Der empirische Teil der Arbeit beschreibt zwei EKP-Experimente, in denen langsame Potentiale zur Untersuchung dieser Modellkonzepte herangezogen wurden. Das Ausmaß kortikaler Aktivierung und Deaktivierung bei Introvertierten vs. Extravertierten in Abhängigkeit von variierenden Anforderungen an Reizanalyse und Reaktionsorganisation wurde über die Contingent Negative Variation (CNV) abgebildet. Aufgrund theoretischer wie empirischer Überlegungen wurde davon ausgegangen, dass sich Unterschiede in der Reizanalyse in der initial CNV (iCNV), Unterschiede in der Reaktionsorganisation dagegen in der terminal CNV (tCNV) niederschlagen. Die Ergebnisse bestätigen, dass der Einsatz psychophysiologischer Methoden zur Theorienprüfung erst dann vielversprechend ist, wenn zuvor eine Validierung der elektrophysiologischen Maße als geeignete Indikatoren für die psychologischen Konstrukte erfolgt ist.