The I.A.F.C. Convention-A Record of Accomplishments

The eighth annual convention of the Intercollegiate Association of Forestry Clubs was held at Ames, March 6, 7 and 8. While it would be impossible to print the complete minutes in this number of the Ames Forester, we are greatly pleased to be able to record a few of the high spots of the convention, and publish in full a few of the addresses and topical reports

Land Zoning in Cut-Over Regions

The Town of Minocqua is in the “heart of the lakes” region of northern Wisconsin. Like every other town in the newer north country, so fortunately situated, it advertised far and wide the inviting charm of its crystal lakes and its cool climate tempered by northern forests (or what remained of them). It was equally generous in its welcome to those who came to patronize its existing resorts and to those who came to add wealth by building new homes, new hotels, new farms

Unit Mixed Interval Graphs

In this paper we extend the work of Rautenbach and Szwarcfiter by giving a structural characterization of graphs that can be represented by the intersection of unit intervals that may or may not contain their endpoints. A characterization was proved independently by Joos, however our approach provides an algorithm that produces such a representation, as well as a forbidden graph characterization

Coastal Plain Forests- Colonial and Modern

Fact and legend have been combined to give many of us a somewhat mystical story of our early forest wealth. Authentic records there are, of course, which enable us to picture a little to our satisfaction how these forests appeared to the voyager from across the Atlantic, but even some of these smack more of 17th century press agent tactics fostered by an ambitious trading company, than a sincere effort to record in an impartial way, the facts about our original forests

Wenn das Lesen noch immer stockt : Psychologen und Literaturdidaktiker entwickeln Methoden, um Lesetempo und -verständnis bei Hauptschülern zu fördern

Leseförderung ist seit den ernüchternden Ergebnissen der großen Vergleichsstudien wie PISA und DESI zu einem Dauerthema der deutschen Bildungspolitik und der pädagogischen Leseforschung geworden. Laut PISA-Studie 2000 bleiben rund 23 Prozent der 15-Jährigen beim Lesen unter dem als Mindeststandard definierten Leistungsniveau. Diese »Risikogruppe«, die zum Großteil aus Schülern und Schülerinnen der Hauptschulen besteht, kann altersangemessene Texte nicht adäquat lesen und verstehen. Die Folgen sind weitreichend und werden in der Öffentlichkeit mit Recht unter dem Schlagwort der »Bildungskatastrophe« diskutiert: Schwache Leser können dem textbasierten Unterricht in den verschiedenen Schulfächern meist nicht folgen und sich die Lerninhalte nicht aneignen, was schnell zu schlechten Leistungen in nahezu allen Fächern führt. Diese Jugendlichen erleben alltäglich schulische Misserfolge und können sich nicht angemessen für die stetig steigenden Anforderungen der beruflichen Praxis qualifizieren – in den meisten Fällen werden sie große Mühe haben, einen Ausbildungsplatz zu finden. Die »poor readers« im Bildungskeller der deutschen Schullandschaft sind die wahren Verlierer der sich gegenwärtig etablierenden Informations- und Wissensgesellschaft: Sie steuern bereits im Jugendalter auf Arbeitslosigkeit und gesellschaftliche Desintegration zu. ..

Split graphs and Block Representations

In this paper, we study split graphs and related classes of graphs from the perspective of their sequence of vertex degrees and an associated lattice under majorization. Following the work of Merris in 2003, we define blocks $[\alpha(\pi)|\beta(\pi)]$, where $\pi$ is the degree sequence of a graph, and $\alpha(\pi)$ and $\beta(\pi)$ are sequences arising from $\pi$. We use the block representation $[\alpha(\pi)|\beta(\pi)]$ to characterize membership in each of the following classes: unbalanced split graphs, balanced split graphs, pseudo-split graphs, and three kinds of Nordhaus-Gaddum graphs (defined by Collins and Trenk in 2013). As in Merris' work, we form a poset under the relation majorization in which the elements are the blocks $[\alpha(\pi)|\beta(\pi)]$ representing split graphs with a fixed number of edges. We partition this poset in several interesting ways using what we call amphoras, and prove upward and downward closure results for blocks arising from different families of graphs. Finally, we show that the poset becomes a lattice when a maximum and minimum element are added, and we prove properties of the meet and join of two blocks.Comment: 23 pages, 7 Figures, 2 Table