53 research outputs found
Text Augmentation: Inserting markup into natural language text with PPM Models
No full textThis thesis describes a new optimisation and new heuristics for automatically marking up XML documents. These are implemented in CEM, using PPMmodels. CEM is significantly more general than previous systems, marking up large numbers of hierarchical tags, using n-gram models for large n and a variety of escape methods.
Four corpora are discussed, including the bibliography corpus of 14682 bibliographies laid out in seven standard styles using the BIBTEX system and markedup in XML with every field from the original BIBTEX. Other corpora include the ROCLING Chinese text segmentation corpus, the Computists’ Communique corpus and the Reuters’ corpus. A detailed examination is presented of the methods of evaluating mark up algorithms, including computation complexity measures and correctness measures from the fields of information retrieval, string processing, machine learning and information theory.
A new taxonomy of markup complexities is established and the properties of each taxon are examined in relation to the complexity of marked-up documents. The performance of the new heuristics and optimisation is examined using the four corpora
Immanuel Kants Leben in Darstellungen seiner Zeitgenossen R. B. Jachmann, L. E. Borowski, A. Ch. Wasianski 1804
No full textElephants and woodlands II
No full textThe paper clarifies and expands on ideas relating to the interaction between elephants and woodlands. Aspects of elephant dietary requirements and woodland response to elephant damage are discussed. Instability of woodlands in arid eutrophic areas is the outcome between a number of factors, including seed germination, amount of browsing, season during which major browsing take place, regeneration of woody plants after breakage by animals, soil nutrient availability and shade intolerance. The author notes that the so called non-damaging trait of the desert elephants in Namibia may be related to the time of year during which the animals tend to browse in different locations
Charitēs, Friedrich Leo zum sechzigsten Geburtstag dargebracht.
No full textBögel, Th. Zum zweiten und dritten Buch von Ciceros Schrift De legibus.--Bruhn, E. De Menone Larisaeo.--Bürger, R. Beiträge zur elegantia Tibulls.--Capelle, W. Die Alexanderzitate bei Olympidor.--Crönert, G. De Lobone Argivo.--Hobein, H. Zweck und Bedeutung der ersten Rede des Maximus Tyrius.--Hubert, K. Zur Entstehung der Tischgespräche Plutarchs.--Jachmann, G. Die Komposition des Plautinischen Poenulus.--Jacobsohn, H. Zur Stammbildung der Nomina im Lateinischen und Indogermanischen.--Jacobsthal, P. Zur Kunstgeschichte der griechischen Inschriften.--Münscher, K. Der Abschnitt vom Rhythmus in Ciceros Orator.--Pasquali, G. Das Proömium des Arat.--Pohlenz, M. Die hellenistische Poesie und die Philosophie.--Schmidt, K.F.W. Menanders Perikeiromene vs. 81-104.--Schultz, H. Die Georgica in Vergils Stilentwicklung.--Sjögren, H. Adnotationes criticae in Ciceronis Epistulas ad Atticum.--Stavenhagen, K. Platōnos prōtos ploūs.--Vollgraff, G. Menandrea.--Weber, L. Zur Münzprägung des phrygischen Hierapolis.--Wegehaupt, H. Plutarch Poteronudōrēpūrchrsimōterou.--Ziebarth, E. Der Eid vom Kloster Lorsch.Mode of access: Internet
On the difference between exclosures and enclosures in ecology and the environment
No full textRehabilitation of degraded land in arid and semiarid environments often involves excluding livestock from degraded sites, creating what are usually but unfortunately not consistently, called _exclosures_. Their main objective is to allow native vegetation to regenerate as a means of providing fodder and woody biomass, to reduce soil erosion and to increase rain water infiltration. We are concerned that some of the alternative names for this practice that are reported in the international literature, including _closed area_, _area closure_ and _enclosure_, may lead to confusion and misunderstanding, especially when these are used as synonyms. Here we aim to illustrate the difference between exclosures and enclosures using recent ecological and environmental literature and provide guidance for their proper use
Developing and assessing a population monitoring program for Dorcas gazelle (Gazella dorcas) using distance sampling in Southern Sinai, Egypt
No full textA monitoring programme to provide information about the dorcas gazelle population
in two regions (the Qa’a plain and the littoral plain and wadies of the Nabaq Protected
Area) of South Sinai, Egypt was developed. Changes in dung density, estimated using
distance sampling, are used as an index of changes in population size.
The two regions were divided into low and high density strata using the results
of earlier surveys. Parallel transects were arranged in a regular pattern to ensure that
maximum survey effort is allocated to the high density strata while keeping a
representative cover of the low density ones. DISTANCE® 4.0 software was used to
model the probability of detecting dung using half normal and hazard rate functions,
and the Akaike information criterion to select between models. Habitat and terrain
types were incorporated as covariates. The effects of biases caused by observer
behaviour on the detection function were investigated. Five plots in the Qa’a plain
were monitored for 15 months to estimate the annual decay rate of the dorcas gazelle
dung using local regression.
The statistical power of the programme to detect population trends over time
was assessed using time series provided by National Parks of Egypt starting in 1999
in addition to estimates resulting from the present work.
Spatial heterogeneity of dung density over the Qa’a plain was investigated
using a Generalized Additive Model with gazelle dung density as the response
variable and camel dung encounter rate, latitude, longitude and distance from the
mountain edge as explanatory variables. The resulting model was used to predict
spatial variation in gazelle dung density over the Qa’a plain using a Geographical
Information System. The model fit was evaluated using graphical methods and Jack-knife resampling
Standard industry components as I/O extension for an Interlock System at PITZ, MTF and XFEL
No full textRecent upgrade of the PITZ facility
No full textThe Photo Injector Test facility at DESY, Zeuthen site (PITZ), is dedicated to develop and optimize high brightness electron sources for short wavelength Free-Electron Lasers (FELs) like FLASH and the European XFEL, both in Hamburg (Germany). Since October 2009 a major upgrade is ongoing with the goal to improve the accelerating components, the photocathode drive laser system and the beam diagnostics as well. The essential new feature in the running will be an in-vacuum 10 MW RF directional coupler to be used for the RF monitoring and control. In this context a significant improvement of the RF stability is expected. RF pulses of 800 microseconds with 10 Hz repetition rate will be used. The most important upgrade of the diagnostics system will be the implementation of a phase space tomography module (PST) consisting of three FODO cells each surrounded by two screen stations. The goal is an improved measurement of the transverse phase space at different charge levels. The upgraded facility will be described
Experimentally minimized beam emittance from an L-band photoinjector
No full textHigh brightness electron sources for linac based free-electron lasers (FELs) are being developed at the Photo Injector Test facility at DESY, Zeuthen site (PITZ). Production of electron bunches with extremely small transverse emittance is the focus of the PITZ scientific program. The photoinjector optimization in 2008–2009 for a bunch charge of 1, 0.5, 0.25, and 0.1 nC resulted in measured emittance values which are beyond the requirements of the European XFEL [S. Rimjaem et al., Nucl. Instrum. Methods Phys. Res., Sect. A 671, 62 (2012)NIMAER0168-900210.1016/j.nima.2011.12.101]. Several essential modifications were commissioned in 2010–2011 at PITZ, resulting in further improvement of the photoinjector performance. Significant improvement of the rf gun phase stability is a major contribution in the reduction of the measured transverse emittance. The old TESLA prototype booster was replaced by a new cut disk structure cavity. This allows acceleration of the electron beam to higher energies and supports much higher flexibility for stable booster operation as well as for longer rf pulses which is of vital importance especially for the emittance optimization of low charge bunches. The transverse phase space of the electron beam was optimized at PITZ for bunch charges in the range between 0.02 and 2 nC, where the quality of the beam measurements was preserved by utilizing long pulse train operation. The experimental optimization yielded worldwide unprecedented low normalized emittance beams in the whole charge range studied
Status of the L-band gun development at PITZ
No full textGun5, the new generation of high-gradient normal conducting 1.3 GHz RF guns for linac driven free-electron lasers like FLASH and European XFEL is under development at the Photo Injector Testfacility at DESY in Zeuthen (PITZ). Its improved cell geometry and cooling concept allow for RF pulse durations of up to 1 ms at 10 Hz repetition rate, at gradients of ~60 MV/m at the cathode. Gun5 is alsoequipped with an RF probe for measurements of the RF field inside the gun.The first gun of this type, Gun5.1, is in operation at PITZ since April 2022. Gun5.2 will be commissioned at the FALCO conditioning facility at DESY in Hamburg, starting in June 2024. This gun is equipped witha balanced (symmetric) RF waveguide feed to the coaxial power coupler to prevent a coupler kick and thus improve the beam quality delivered by the electron source. Further guns are currently in themanufacturing process. In parallel, studies towards a more reliable cathode spring design are ongoing, in order to overcome observed issues during the high duty cycle operation of Gun5.1
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