In this thesis, we study the representation of speech signals and the estimation of information-theoretical measures from observations containing features of the speech signal. The main body of the thesis consists of four research papers. Paper A presents a compact representation of the speech signal that facilitates perfect reconstruction. The representation is constituted of models, model parameters, and signal coefficients. A difference compared to existing speech representations is that we seek a compact representation by adapting the models to maximally concentrate the energy of the signal coefficients according to a selected energy concentration criterion. The individual parts of the representation are closely related to speech signal properties such as spectral envelope, pitch, and voiced/unvoiced signal coefficients, bene cial for both speech coding and modi cation. From the information-theoretical measure of entropy, performance limits in coding and classi cation can be derived. Papers B and C discuss the estimation of di erential entropy. Paper B describes a method for estimation of the di erential entropies in the case when the set of vector observations (from the representation) lie on a lower-dimensional surface (manifold) in the embedding space. In contrast to the method presented in Paper B, Paper C introduces a method where the manifold structures are destroyed by constraining the resolution of the observation space. This facilitates the estimation of bounds on classi cation error rates even when the manifolds are of varying dimensionality within the embedding space. Finally, Paper D investigates the amount of shared information between spectral features of narrow-band (0.3-3.4 kHz) and high-band (3.4-8 kHz) speech. The results in Paper D indicate that the information shared between the high-band and the narrow-band is insufficient for high-quality wideband speech coding (0.3-8 kHz) without transmission of extra information describing the high-band. / QC 20100914

Dietary energy is the largest single cost in pork production. Accurate and current understanding of energy metabolism is crucial to production efficiency. The overall objective of this thesis was to evaluate the effects of dietary energy concentration and energy intake on growth, nutrient deposition rates and energy utilization in weaned pigs. In experiment 1, the optimum total lysine:DE ratio for weaned pigs was estimated at 4.27 and 4.46 g/Mcal for pigs growing from 7.5 to 12.8 kg and 7.5 to 22.5 kg BW, respectively. Experiment 2 determined if a more predictable growth, nutrient deposition and energy utilization in the weaned pig is achieved with NE or with DE. ADG either remained similar or was depressed with increased NE compared to the control (P < 0.05). Empty body protein content and deposition (PD) declined relative to the control (P < 0.05) and lipid content and deposition (LD) tended to increase (P < 0.10). Body composition and nutrient deposition rates were more correlated with determined NE concentration and intake compared with DE. The results of Experiment 3 indicated that amino acid intake impaired the growth of pigs when an energy intake restriction greater than 30% occurred. Experiment 4 investigated the interaction of dietary NE concentration and feeding levels (FL) on body weight gain, tissue (protein, lipid, ash, water) accretion rates and ratios. Growth performance was not affected by NE (P > 0.05) but increased with feeding level (P < 0.001). Energy intake increased with NE and FL (P < 0.001), but the efficiency of energy utilization for growth declined (P < 0.05). Empty body protein content declined (P < 0.05) while lipid content increased with NE (interaction, P < 0.05). Empty body PD was not affected by NE (P > 0.05) but both LD and LD:PD ratio increased (interaction, P < 0.001). These data suggest that when amino acid:energy ratio is optimal, increasing dietary energy concentration increased energy intake but does not improve PD and overall body weight gain of weaned pigs. However, body lipid content and LD were increased. Finally, NE offers an advantage over the DE in predicting the body composition and nutrient deposition rates rather than in overall BW gain.

Dietary energy is the largest single cost in pork production. Accurate and current understanding of energy metabolism is crucial to production efficiency. The overall objective of this thesis was to evaluate the effects of dietary energy concentration and energy intake on growth, nutrient deposition rates and energy utilization in weaned pigs. In experiment 1, the optimum total lysine:DE ratio for weaned pigs was estimated at 4.27 and 4.46 g/Mcal for pigs growing from 7.5 to 12.8 kg and 7.5 to 22.5 kg BW, respectively. Experiment 2 determined if a more predictable growth, nutrient deposition and energy utilization in the weaned pig is achieved with NE or with DE. ADG either remained similar or was depressed with increased NE compared to the control (P < 0.05). Empty body protein content and deposition (PD) declined relative to the control (P < 0.05) and lipid content and deposition (LD) tended to increase (P < 0.10). Body composition and nutrient deposition rates were more correlated with determined NE concentration and intake compared with DE. The results of Experiment 3 indicated that amino acid intake impaired the growth of pigs when an energy intake restriction greater than 30% occurred. Experiment 4 investigated the interaction of dietary NE concentration and feeding levels (FL) on body weight gain, tissue (protein, lipid, ash, water) accretion rates and ratios. Growth performance was not affected by NE (P > 0.05) but increased with feeding level (P < 0.001). Energy intake increased with NE and FL (P < 0.001), but the efficiency of energy utilization for growth declined (P < 0.05). Empty body protein content declined (P < 0.05) while lipid content increased with NE (interaction, P < 0.05). Empty body PD was not affected by NE (P > 0.05) but both LD and LD:PD ratio increased (interaction, P < 0.001). These data suggest that when amino acid:energy ratio is optimal, increasing dietary energy concentration increased energy intake but does not improve PD and overall body weight gain of weaned pigs. However, body lipid content and LD were increased. Finally, NE offers an advantage over the DE in predicting the body composition and nutrient deposition rates rather than in overall BW gain.

Im nordostdeutschen Land ist die Zunahme des Ertrages und die Verbesserung der Qualität des Maises eine Folge von Licht, Temperatur und der Länge der Vegetationsperiode. Eine gute Belichtung durch blattreichere Sorten und Standort angepasste Bestandesdichte ist wichtige Voraussetzung für die gute Ertragsleistung des Silomaises. Am Standort Berge (nordostdeutsches Tiefland) sind in den Jahren 1997 und 1998 vier Landessortenversuche (Brandenburg) und zwei Parzellenversuche mit verschiedenen Silomaissorten und Bestandsdichten in die Untersuchungen zum Ertragsniveau, zur Futterqualität und zum Einfluss des Faktors Licht auf die Ertragsbildung bei Silomais einbezogen worden. Es handelte sich im Landessortenversuch um Untersuchungen in den Silomaissortimenten der Reifegruppe "früh" mit 28 Sorten und der Reifegruppe "mittelfrüh" mit 33 Sorten. In ergänzenden Parzellenversuchen ging es um detaillierte Untersuchungen zur Lichtinterzeption und des Blattflächenindexes in Abhängigkeit vom Wuchstyp der Maissorten sowie von der Bestandsdichte. Am Beginn der Untersuchungen standen die Sortenunterschiede bei den Merkmalen Gesamtertrag, Futterqualität (wie Trockensubstanzgehalt, Energiedichte und Stärkegehalt) und Lichtinterzeption im Mittelpunkt. Darauf aufbauend konzentrierten sich die Untersuchungen auf den Einfluss von Sorte und Bestandsdichte auf die vor allem auf den Ertragsparameter Trockenmassebildung in unterschiedlichen Wuchsabschnitten der Maispflanze, Kolbenanteil am Trockenmasseertrag, die Blattflächen, den Blattflächenindex, die Lebensdauer der Blätter und die Lichtaufnahme [wie die Lichtinterzeption, den Lichtextinktionskoeffizienten und die Lichtnutzungseffizienz]. Dazu wurden im Jahre 1998 zwei Parzellenversuche mit je zwei Sorten der Reifegruppen "früh" (Arsenal und Agadir) und "mittelfrüh" (Banguy und Attribut) angelegt. In den zweifaktoriellen Parzellenversuchen wurden bei der Messung der Lichtinterzeption zwei Messgeräte (PhAR-Sensor und LAI-2000) verwendet. Für die Messung des Blattflächenindexes wurde ebenfalls das Messgerät LAI-2000 verwendet. Der Blattflächenindex wurde mit den Ergebnissen aus der manuellen Messung der einzelnen Blätter verglichen. Die Sorten Arsenal und Banguy zeichneten sich durch die höhere Lichtnutzungseffizienz, den größeren Blattflächenindex und die größere Lichtinterzeption aus, was als Grund für den höheren Ertrag angesehen werden kann. Im Jahre 1998 führte die höhere Bestandesdichte von 10 Pflanzen pro qm im Vergleich zu 8 Pflanzen pro qm unter den herrschenden Standortverhältnissen zu keiner Ertragsüberlegenheit und es kam zu schlechteren Qualitätseigenschaften der vier Sorten. Der Unterschied zwischen den Werten des Blattflächenindexes der beiden Messmethoden bei Erreichen des maximalen Blattflächenindexes war kleiner als 14 %. / The higher yield and the better quality of maize depend on light, temperature, water and length of vegetation period in north eastern Germany. A good light interception of maize accompanied with higher leaf area index and plant density adjusted to region is essential for the better maize yield. In 1997 and 1998 four field trials for assessing varieties for the conditions of the federal state Brandenburg (variety trials) and two field experiments with four silage maize varieties and different plant densities in 1998 were carried out at Berge (plain of the north eastern Germany). The yield and the fodder quality of the maize crop (with special emphasis of the light conditions) as well as the effect of light conditions on yield forming out processes were examined. The variety trials included 28 maize varieties of maturity group "early" and 33 maize hybrids of maturity group "middle early". The aim of the two field experiments was to explain the light interception and the leaf area index in dependence of canopy structure and plant density. At the beginning of the variety trials we focused on the differences between the hybrids for maize yield, fodder quality (such as dry matter content, energy concentration and content of starch) and light interception. Closely related experiments were concentrated on the influence of variety and plant density on the yield (dry matter yield within different plant height, cobs weight ratio), development of leaf (leaf area index, leaf area and leaf age) and light absorption (such as light interception, light extinction coefficient and light use efficiency). At these field experiments, to which two hybrids Arsenal and Agadir (maturity group "early") and two hybrids Banguy and Attribut ("middle early") were analysed. In the two-factorial field experiments two devices (ceptometer and LAI-2000) were used to measure the light interception. The leaf area index we obtained from measurement with the LAI-2000 were valued by the leaf area index of individual leafs measured by hand. The hybrids Arsenal and Banguy were characterised by their higher light use efficiency, large leaf area index and higher light interception. These properties seem to be responsible for the higher maize yield. The higher Plant density of 10 plant per sqm for the four varieties compared to 8 plant per sqm resulted in no increase of yield and worse qualities in 1998. The difference between the maximum value of leaf area index of both methods was smaller than 14 %.