Distance education at conventional universities in Germany

Germany’s educational system has undergone a series of transformations during the last 40 years. In recent years, marked increases in enrolment have occurred. In response, admission requirements have been relaxed and new universities have been established. Academic distance education in the former Federal Republic of Germany (West Germany) was ushered in by the educational radio broadcasts around the end of the 1960s. Aside from the formation of the FernUniversität (Open University) in West Germany in 1975, there were significant developments in distance education occurring at the major universities in the German Democratic Republic (East Germany). After German reunification in 1990, the new unitary state launched programs to advance the development of distance education programs at conventional universities. Germany’s campus-based universities (Präsenzuniversitäten) created various entities, including central units and consortia of universities to design and market distance education programs. Hybridisation provides the necessary prerequisites for dual mode delivery, such as basic and continuing education programs, as well as for the combination of distance and campus-based education (Präsenzstudium). Hybridisation also has also opened the door for the creation of new programs. Following an initial phase in which distance education research is expected to centralize a trend towards decentralisation is likely to follow. The German Association for Distance Education (AG-F) offers a viable research network in distance education. Two dual mode case studies are also be surveyed: The Master of Arts degree, offered by the University of Koblenz-Landau, with Library Science as the second major, and the University of Kaiserslautern, where basic education will continue to be captured within the domain of the Präsenzstudium or campus-based education. The area in which distance education is flourishing most is within the field of academic continuing education, where external experts and authors are broadening the horizon of the campus. Multimedia networks will comprise the third generation of distance education

The nearby population of M dwarfs with WISE: A search for warm circumstellar dust

Circumstellar debris disks are important because of their connection to planetary systems. An efficient way to identify these systems is through their infrared excess. Most studies so far concentrated on early-type or solar-type stars, but less effort has gone into investigating M dwarfs. We characterize the mid-infrared photometric behavior of M dwarfs and search for infrared excess in nearby M dwarfs taken from the volume-limited RECONS sample using data from the WISE satellite and the 2MASS catalog. Our sample consists of 85 sources encompassing 103 M dwarfs. We derive empirical infrared colors from these data and discuss their errors. Based on this, we check the stars for infrared excess and discuss the minimum excess we would be able to detect. Other than the M8.5 dwarf SCR 1845-6357 A, where the excess is produced by a known T6 companion, we detect no excesses in any of our sample stars. The limits we derive for the 22um excess are slightly higher than the usual detection limit of 10-15% for Spitzer studies, but including the [12]-[22] color in our analysis allows us to derive tight constraints on the fractional dust luminosity L_dust/L_star. We show that this result is consistent with M dwarf excesses in the mid-inrared being as frequent as excesses around earlier-type stars. The low detection rate could be an age effect. We also present a tentative excess detection at 22um around the known cold debris disk M dwarf AU Mic, which is not part of our statistical sample. There is still no clear detection of a mid-infrared excess around any old (>30 Myr) main-sequence M dwarf. It is unclear whether this is due to a different dust evolution around M dwarfs or whether this is an age effect combined with the diffculties involved in searching M dwarfs for infrared excesses. A significantly larger sample of well-studied M dwarfs is required to solve this question.Comment: Accepted for publication in A&A, 15 pages, 7 figure

Individual plant care in cropping systems

Individual plant care cropping systems, embodied in precision farming, may lead to new opportunities in agricultural crop management. The objective of the project was to provide high accuracy seed position mapping of a field of sugar beet. An RTK GPS was retrofitted on to a precision seeder to map the seeds as they were planted. The average error between the seed map and the actual plant map was about 32 mm to 59 mm. The results showed that the overall accuracy of the estimated plant positions is acceptable for the guidance of vehicles and implements. For subsequent individual plant care, the deviations were not, in all cases, small enough to ensure accurate individual plant targeting

Tipos de encogimiento de los géneros de punto de lana y su medida.

Exposición de los tipos más importantes de encogimiento de los géneros de punto y la medida de dichos encogimientos.Peer Reviewe

Microcinématographie d'objets sensibles à la lumière, a l'aide de vidéocaméras

Bei mikrokinematographischen Untersuchungen lichtempfindlicher Objekte besteht häufig das Problem, daß das Objekt bereits auf das Aufnahmelicht reagiert und dadurch die zu untersuchenden Phänomene verfälscht werden können. Das ist insbesondere dann der Fall, wenn die phototropische Reaktion selbst Gegenstand der Untersuchung ist. Mehrere Möglichkeiten zur Überwindung dieser Schwierigkeit werden beschrieben: die Verwendung von Licht aus einem Spektralbereich, für den das Objekt unempfindlich ist („Sicherheitslicht"), ferner die Verwendung einer speziellen Aufnahmeanordnung, die es erlaubt, das Aufnahmelicht genügend zu reduzieren, und vor allem die Aufnahme mit Hilfe einer hochempfindlichen Videokamera.Lors d'études microcinématographiques d'objets sensibles à la-caméras. lumière, il se pose souvent le problème suivant: l'objet réagit à la lumière de prise de vues, ce qui peut déjà fausser les phénomènes à étudier. Ceci est notamment le cas lorsque la réaction phototropique elle-même fait l'objet de l'étude. Diverses possibilités permettant de surmonter cette difficulté sont décrites: l'éclairage an moyen d'un domaine du spectre auquel l'objet n'est pas sensible ("lumière de sécurité"), de plus, l'utilisation d'un équipement spécial de prises de vues qui permette de réduire suffisamment l'éclairage et surtout prises de vues à l'aide d'une vidéo caméra extrêmement sensible.Cinemicrography of Light-sensitive Objects by Means of Video Cameras. When cinemierographic investigations of light-sensitive objects are carried out the following problem often occurs: The object already responds to the light which is used for recording and by this the phenomena under investigation can be falsified. This is especially the case when the phototropic reaction is to be investigated. Some possibilities to overcome this difficulties are described: Illumination with light of a spectral region the object is insensitive of ("safety light"), furthermore the use of a special recording device allowing to reduce the light efficiently and, above all, the recording by means of a video camera of high sensibility

Seed Mapping of Sugar Beet

Individual plant care may well become embodied in precision farming in the future and will lead to new opportunities in agricultural crop management. The objective of this project was to develop and evaluate a data logging system attached to a precision seeder to enable high accuracy seed position mapping of a field of sugar beet. A Real Time Kinematic Global Positioning System (RTK GPS), optical seed detectors and a data logging system were retrofitted on to a precision seeder to map the seeds as they were planted. The average error between the seed map and the actual plant map was about 16–43 mm depending on vehicle speed and seed spacing. The results showed that the overall accuracy of the estimated plant positions was acceptable for the guidance of vehicles and implements as well as potential individual plant treatments