National Water Resources Policy Issues

Syftet med mitt arbete är att undersöka vad elever i klass 7 och klass 8 som läser spanska som andra språk ser som motiverande för sina spanskstudier. Jag ville även titta närmare vad som kan skapa motivation hos eleverna. I min undersökning ville jag också undersöka vilka strategier lärare har för att öka elevernas motivation för att läsa spanska. Som metod valde jag att göra en enkätundersökning bland i elever som går i Åk 7 och Åk 8 på två kommunala skolor och två friskolor. Dessutom har jag intervjuat två undervisade spansklärare. Studien visade att lärarna har mycket stor betydelse för elevernas motivation och de beskriver att de blir mest motiverade av ha en rolig, trevlig och kompetent lärare. Men även arbetsmiljön är viktig, för att kunna koncentrerar sig på undervisningen under lektionerna. Lärarna beskriver också vilka aktiviteter och metoder de använder för att höja motivation hos eleverna. Lärarna pekar bland annat på att de försöker välja intressant material för att kunna göra effektiva och givande lektioner. Lärarna ser också att elevernas motivation höjs om de får vara med och välja material som de ska arbeta med

Approximation algorithms for hard variants of the stable marriage and hospitals/residents problems

When ties and incomplete preference lists are permitted in the Stable Marriage and Hospitals/Residents problems, stable matchings can have different sizes. The problem of finding a maximum cardinality stable matching in this context is known to be NP-hard, even under very severe restrictions on the number, size and position of ties. In this paper, we describe polynomial-time 5/3-approximation algorithms for variants of these problems in which ties are on one side only and at the end of the preference lists. The particular variant is motivated by important applications in large scale centralised matching schemes

Popular matchings

We consider the problem of matching a set of applicants to a set of posts, where each applicant has a preference list, ranking a non-empty subset of posts in order of preference, possibly involving ties. We say that a matching M is popular if there is no matching M' such that the number of applicants preferring M' to M exceeds the number of applicants preferring M to M'. In this paper, we give the first polynomial-time algorithms to determine if an instance admits a popular matching, and to find a largest such matching, if one exists. For the special case in which every preference list is strictly ordered (i.e. contains no ties), we give an O(n+m) time algorithm, where n is the total number of applicants and posts, and m is the total length of all the preference lists. For the general case in which preference lists may contain ties, we give an O(√nm) time algorithm, and show that the problem has equivalent time complexity to the maximum-cardinality bipartite matching problem

An Ecological Study of Timberline and Alpine Areas, Mount Lincoln, Park County, Colorado

During the short alpine growing season of 1945 the authors had the opportunity of studying conditions and biota on Mount Lincoln, Park County, Colorado, in an attempt to evaluate the ecological conditions and animal communities of the area. Of the large amount of taxonomic and ecological zoology published on the state, most has been in the field of autecology, and, except in the province of aquatic studies, little has appeared bearing on synecological relations, especially among invertebrates. The marked differences between the physiography, climatology, and biology of timberline, alpine, and other stations seemed to offer a field well worthy of investigation. Since the work was done, other factors have been introduced which have greatly altered the nearly primitive conditions encountered at the time of the investigation. One of the areas has been entirely destroyed by the formation of a water storage lake, and others have been affected through heavy summer grazing by bands of sheep. The material published on the Mount Lincoln area is very limited. Cary (1911) was concerned with similar areas in other parts of the state, but apparently he did not work around the mountains at the head of the South Platte. The most detailed paper on the region is that of Patton and his collaborators (1912) which covers the physiography very completely. There are scattered references to the animal life of the vicinity in Coues (1874), Sclater (1912), Warren (1942), and elsewhere. The most complete published reports on the animal life of the region are those of Brewer (1871) and Allen (1872, 1876a, 1876b); the first of Allen\u27s papers is the source of most of Coues\u27 references to the Mount Lincoln avifauna. None of these papers deals with the invertebrates, save for comments by Brewer on the relative abundance of certain orders of insects

Use of COTS functional analysis software as an IVHM design tool for detection and isolation of UAV fuel system faults

This paper presents a new approach to the development of health management solutions which can be applied to both new and legacy platforms during the conceptual design phase. The approach involves the qualitative functional modelling of a system in order to perform an Integrated Vehicle Health Management (IVHM) design – the placement of sensors and the diagnostic rules to be used in interrogating their output. The qualitative functional analysis was chosen as a route for early assessment of failures in complex systems. Functional models of system components are required for capturing the available system knowledge used during various stages of system and IVHM design. MADe™ (Maintenance Aware Design environment), a COTS software tool developed by PHM Technology, was used for the health management design. A model has been built incorporating the failure diagrams of five failure modes for five different components of a UAV fuel system. Thus an inherent health management solution for the system and the optimised sensor set solution have been defined. The automatically generated sensor set solution also contains a diagnostic rule set, which was validated on the fuel rig for different operation modes taking into account the predicted fault detection/isolation and ambiguity group coefficients. It was concluded that when using functional modelling, the IVHM design and the actual system design cannot be done in isolation. The functional approach requires permanent input from the system designer and reliability engineers in order to construct a functional model that will qualitatively represent the real system. In other words, the physical insight should not be isolated from the failure phenomena and the diagnostic analysis tools should be able to adequately capture the experience bases. This approach has been verified on a laboratory bench top test rig which can simulate a range of possible fuel system faults. The rig is fully instrumented in order to allow benchmarking of various sensing solution for fault detection/isolation that were identified using functional analysis

Heteroepitaxial InP solar cells on Si and GaAs substrates

The characteristics of InP cells processed from thin layers of InP heteroepitaxially grown on GaAs, on silicon with an intervening GaAs layer, and on GaAs with intervening Ga(x)In(1-x)As layers are described, and the factors affecting cell efficiency are discussed. Under 10 MeV proton irradiations, the radiation resistances of the heteroepitaxial cells were superior to that of homoepitaxial InP cells. The superior radiation resistance is attributed to the high dislocation densities present in the heteroepitaxial cells

Diffusion length variation in 0.5- and 3-MeV-proton-irradiated, heteroepitaxial indium phosphide solar cells

Indium phosphide (InP) solar cells are more radiation resistant than gallium arsenide (GaAs) and silicon (Si) solar cells, and their growth by heteroepitaxy offers additional advantages leading to the development of light weight, mechanically strong, and cost-effective cells. Changes in heteroepitaxial InP cell efficiency under 0.5- and 3-MeV proton irradiations have been explained by the variation in the minority-carrier diffusion length. The base diffusion length versus proton fluence was calculated by simulating the cell performance. The diffusion length damage coefficient, K(sub L), was also plotted as a function of proton fluence