Free Deterministic Equivalents for the Analysis of MIMO Multiple Access Channel

In this paper, a free deterministic equivalent is proposed for the capacity analysis of the multi-input multi-output (MIMO) multiple access channel (MAC) with a more general channel model compared to previous works. Specifically, a MIMO MAC with one base station (BS) equipped with several distributed antenna sets is considered. Each link between a user and a BS antenna set forms a jointly correlated Rician fading channel. The analysis is based on operator-valued free probability theory, which broadens the range of applicability of free probability techniques tremendously. By replacing independent Gaussian random matrices with operator-valued random variables satisfying certain operator-valued freeness relations, the free deterministic equivalent of the considered channel Gram matrix is obtained. The Shannon transform of the free deterministic equivalent is derived, which provides an approximate expression for the ergodic input-output mutual information of the channel. The sum-rate capacity achieving input covariance matrices are also derived based on the approximate ergodic input-output mutual information. The free deterministic equivalent results are easy to compute, and simulation results show that these approximations are numerically accurate and computationally efficient.Comment: 26 pages, 7 figures, Accepted by IEEE Transactions on Information Theor

Plant protection in organic apple production: A summary of research conducted under the German Federal Programme for Organic Agriculture and other forms of Sustainable Agriculture

In this focus area, research projects were carried out on two main subjects: apple scab (Venturia inaequalis) and codling moth (Cydia pomonella). Scab control projects started in 2002, projects on codling moth control in 2006, and research on both topics has intensified since 2010. From the be-ginning, the search for alternative materials for scab control was prioritised, since the use of copper as a treatment for scab is going to be restricted in the future, and the efficiency of materials approved for treating organic apples has often been too low in the past to prevent significant yield losses. Alternative materials were tested and compared, including materials from Inula viscosa, Quillaja saponaria bark, citrus species and Saponaria officinalis. These plant-derived products were able to significantly reduce ascospore potential of scab in greenhouse experiments. The combination of Quillaja saponin and sulphur reduced scab very strongly. The combination of citrus extract with GREEMAX and BIOPLUSS as adhesives had a similar effect as a quantity of 400g Cu/ha (applied as copper oxychloride) in field trials. Targeted treatments with lime sulphur during the time of sporulation were found to represent a good and safe alternative. Gloeosporium infestation was significantly reduced by additional MycoSin treatments before harvest. Furthermore, autumn foliage removal with leaf blowers, and the promotion of earthworm activity was tested to reduce fungal inoculum. The aim of these studies was to identify ecologically compatible substances that lead to a reduction of scab infestation. Based on the initial results of the past years, on-going projects are investigating new alternative methods, application techniques and other solutions for the reduction of copper use in organic apple production. In recent years, codling moth populations have appeared that showed low susceptibility to the com-monly used codling moth granulovirus (CpGV) preparations, and thus cannot be properly controlled with this treatment. Following research that clarified and described the unusual inheritance of virus resistance in codling moth, new CpGV isolates were developed that are able to break this resistance. Commercial farms with CpGV resistance or suspected resistance are recommended to use the new, resistance-breaking virus isolates. In on-going experiments, other methods of codling moth control are being tested, such as the use of nematodes and Trichogramma wasps. Investigation of the indi-viduals resistant to new and other potential isolates of CpGV as well as a risk assessment regarding resistance development are prioritised in the current projects. Further results from the BÖLN research on pest management in organic fruit growing are regularly published at www.bundesprogramm-oekolandbau.de

Current algebra based effective chiral theory of mesons and a new EW theory

A current algebra based effective chiral theory of pseudoscalar, vector, axial-vector mesons is reviewed. A new mechanism generating the masses and guage fixing terms of gauge boson is revealed from this effective theory. A EW theory without Higgs is proposed. The masses and gauge fixing terms of W and Z are dynamically generated. Three heavy scalar fields are dynamically generated too. They are ghosts.Comment: 4 pages, talk presented at conference of QCD and hadronic physics, 6/16-6/21, Beijing, Chin

Effect of dissipative forces on the theory of a single-atom microlaser

We describe a one-atom microlaser involving Poissonian input of atoms with a fixed flight time through an optical resonator. The influence of the cavity reservoir during the interactions of successive individual atoms with the cavity field is included in the analysis. The atomic decay is also considered as it is nonnegligible in the optical regime. During the random intervals of absence of any atom in the cavity, the field evolves under its own dynamics. We discuss the steady-state characteristics of the cavity field. Away from laser threshold, the field can be nonclassical in nature.Comment: 9 pages in LaTex; 3 PS figure

Nutrition of monogastrics: A summary of research conducted under the German Federal Programme for Organic Agriculture and other forms of Sustainable Agriculture

The thematic focus of monogastric nutrition runs very regularly through the entire federal programme. A strong focus was on the use of feed made from 100% organic origin (EC Eco-Regulation). In experiments in 2006 on the use of roughage in outdoor rearing pigs, for example, it was shown that Jerusalem artichoke can lead to significantly higher weight gains, compared to the control, while weight gain decreased significantly in some cases using other roughages. In another project in 2007, the various processing methods for soybean cake and feed produced therefrom were tested on broiler chickens, laying hens and pigs. The aim was to develop a suitable technology to inactivate the anti-nutritive components in soy and thus to increase the protein digestibility and the nutritional value. At the same time, as part of a broad collaborative project, the use of five different roughages (straw, hay, clover silage, maize silage and Jerusalem artichokes) were compared in organic piglet production. It could be demonstrated that the feeding of various roughages resulted in a stabilisation of the intestinal flora in comparison to the control group. In particular, by feeding various roughages, the Clostridium perfringens population can be significantly reduced. A review of the compensatory protein uptake of organic pigs has found that it cannot be concluded that an economically relevant compensation takes place, and that under the specific feeding restrictions of organic farming GfE recommendations for lysine supply for the initial fattening period are estimated too high. In studies of different genotypes, management and feeding strategies it was also found that turkey diets with reduced ME (metabolisable energy) and amino acid levels, in combination with free-range management, result in a lower animal loss and high growth and carcass performance. In a review of the use of the microalga Spirulina platensis in a feeding trial with fattening broilers a positive dose-response effect was observed. The higher the amount of Spirulina absorbed, the better the carcass weights. Due to the high cost of the Spirulina product (despite improved fattening and carcass performance) the economics of its use in broiler production are unfavourable. Thus the application of this product is only recommended in the first phase of the rearing (1-14 days). The aim of another project was the development of NIRS calibration which allows a more timely determination of the constituents, especially the protein and amino acid contents (AS), of organically produced grain legumes immediately after harvest, in order to create optimal, demand-based rations. In 2007, a database for feed was created to assist in ration design. In 2011 a number of projects started in which various locally available protein feeding stuffs will be tested in different feeding trials with pigs. The supply of essential amino acids within the available protein feed, especially for poultry, is often insufficient, and another research project is testing approaches to produce high-quality protein feed in the form of clover silage and use this feed in feeding trials with laying hens and broilers. The first results of these projects are expected in 2015. Further results from the BÖLN research on animal nutrition in monogastric animals are regularly published at www.bundesprogramm-oekolandbau.de

Twisted Weyl groups of Lie groups and nonabelian cohomology

For a cyclic group $A$ and a connected Lie group $G$ with an $A$-module structure (with the additional conditions that $G$ is compact and the $A$-module structure on $G$ is 1-semisimple if A\cong\ZZ), we define the twisted Weyl group $W=W(G,A,T)$, which acts on $T$ and $H^1(A,T)$, where $T$ is a maximal compact torus of $G_0^A$, the identity component of the group of invariants $G^A$. We then prove that the natural map $W\backslash H^1(A,T)\to H^1(A,G)$ is a bijection, reducing the calculation of $H^1(A,G)$ to the calculation of the action of $W$ on $T$. We also prove some properties of the twisted Weyl group $W$, one of which is that $W$ is a finite group. A new proof of a known result concerning the ranks of groups of invariants with respect to automorphisms of a compact Lie group is also given.Comment: 9 page