Interacting effects of tillage method,nitrogen fertiliser and secondary drainage on winter wheat production on a calcareous clay soil

The response of winter wheat to nitrogen fertiliser within the range 0–200 kg ha^?1 in 40 kg increments applied either in April or in May in two consecutive seasons (1976–77 and 1977–78) was tested in a field experiment on a calcareous clay soil that was either direct-drilled, shallow tine cultivated (5–8 cm), or mouldboard ploughed (23 cm). These cultivation methods had been used on the same plots in the four preceding seasons (1973 to 1976) in a comparison of cultivation systems. A comparison was also made with direct-drilling on land that had been deep tine cultivated (17 cm) during the 1973–76 experiment. In the second season (1977–78) effects were examined of newly drawn mole drains, on land that had been direct-drilled or ploughed. In both seasons the effect of cultivation method on grain yield was small when nitrogen fertiliser was applied at 80–120 kg N ha^?1. Nitrogen top dressings in April gave heavier yields than the equivalent dressings in May, partly because of dry weather after the May applications in both years. There was no interaction between method of cultivation and amount of nitrogen applied in 1976–77, but a significant interaction was detected in 1977–78 which was probably associated with less nitrogen being available in the uncultivated soil during the winter and spring. The results show that the potential yield of direct-drilled crops may have been underestimated in some earlier comparisons of different methods of cultivation where small uniform top dressings of nitrogen were applied to each cultivation treatment. Mole drainage increased yield especially at low rates of nitrogen and after direct drilling, These results indicate that direct-drilled and ploughed land may differ in their drainage requirements.     

Variational optical flow computation in real time.

This paper investigates the usefulness of bidirectional multigrid methods for variational optical flow computations. Although these numerical schemes are among the fastest methods for solving equation systems, they are rarely applied in the field of computer vision. We demonstrate how to employ those numerical methods for the treatment of variational optical flow formulations and show that the efficiency of this approach even allows for real-time performance on standard PCs. As a representative for variational optic flow methods, we consider the recently introduced combined local-global method. It can be considered as a noise-robust generalization of the Horn and Schunck technique. We present a decoupled, as well as a coupled, version of the classical Gauss-Seidel solver, and we develop several multgrid implementations based on a discretization coarse grid approximation. In contrast, with standard bidirectional multigrid algorithms, we take advantage of intergrid transfer operators that allow for nondyadic grid hierarchies. As a consequence, no restrictions concerning the image size or the number of traversed levels have to be imposed. In the experimental section, we juxtapose the developed multigrid schemes and demonstrate their superior performance when compared to unidirectional multgrid methods and nonhierachical solvers. For the well-known 316 x 252 Yosemite sequence, we succeeded in computing the complete set of dense flow fields in three quarters of a second on a 3.06-GHz Pentium4 PC. This corresponds to a frame rate of 18 flow fields per second which outperforms the widely-used Gauss-Seidel method by almost three orders of magnitude.     

FastFabric: Scaling hyperledger fabric to 20 000 transactions per second

Blockchain technologies are expected to make a significant impact on a variety of industries. However, one issue holding them back is their limited transaction throughput, especially compared to established solutions such as distributed database systems. In this paper, we rearchitect a modern permissioned blockchain system, Hyperledger Fabric, to increase transaction throughput from 3000 to 20 000 transactions per second. We focus on performance bottlenecks beyond the consensus mechanism, and we propose architectural changes that reduce computation and I/O overhead during transaction ordering and validation to greatly improve throughput. Notably, our optimizations are fully plug‐and‐play and do not require any interface changes to Hyperledger Fabric.     

投影用高亮度发光二极管的快速发展

在过去三年中,微型显示投影发光二极管(LED)光学引擎的亮度显著地加速增长,在某种程度上超出了许多业内人士的期望。这种快速增长促进了液晶投影电视的出现。综述了应用于投影的LED的进展及相应产品。讨论了基于LED的光引擎的设计,展望了其亮度改进以及新产品研制的前景。     

Optimal design of Service Overlay Networks with economic and performance constraints

In the last years, Service Overlay Networks (SONs) have emerged as a promising means to address some of the issues (e.g. end‐to‐end QoS) affecting the current Internet and to favor the development and deployment of new value‐added Internet services. The deployment of an SON is a capital‐intensive investment, since bandwidth with certain QoS guarantees must be purchased from the individual network domains through bilateral Service Level Agreements. Thus, minimizing the economic cost of the logical end‐to‐end service delivery infrastructure is one of the key objectives for the SON provider. When a SON is aimed at end‐to‐end QoS provisioning, its topology must be designed so as to also satisfy the specific requirements of QoS‐sensitive applications. This paper deals with the problem of planning the SON topology in order to take into account both cost and QoS constraints. More specifically, the paper proposes a set of new algorithms for the design of an optimized SON topology, which minimizes the economic cost while simultaneously meeting bandwidth and delay constraints. A performance comparison among such algorithms is finally carried out. Copyright © 2009 John Wiley & Sons, Ltd.     

Free-Standing β-Ga<Subscript>2</Subscript>O<Subscript>3</Subscript> Thin Diaphragms

Free-standing, very thin, single-crystal β-gallium oxide (β-Ga₂O₃) diaphragms have been constructed and their dynamical mechanical properties characterized by noncontact, noninvasive optical measurements harnessing the multimode nanomechanical resonances of these suspended nanostructures. We synthesized single-crystal β-Ga₂O₃ using low-pressure chemical vapor deposition (LPCVD) on a 3C-SiC epilayer grown on Si substrate at temperature of 950°C for 1.5 h. The synthesized single-crystal nanoflakes had widths of ～ 2 μm to 30 μm and thicknesses of ～ 20 nm to 140 nm, from which we fabricated free-standing circular drumhead β-Ga₂O₃ diaphragms with thicknesses of ～ 23 nm to 73 nm and diameters of ～ 3.2 μm and ～ 5.2 μm using a dry stamp-transfer technique. Based on measurements of multiple flexural-mode mechanical resonances using ultrasensitive laser interferometric detection and performing thermal annealing at 250°C for 1.5 h, we quantified the effects of annealing and adsorption of atmospheric gas molecules on the resonant characteristics of the diaphragms. Furthermore, we studied the effects of structural nonidealities on these free-standing β-Ga₂O₃ nanoscale diaphragms. We present extensive characterization of the mechanical and optical properties of free-standing β-Ga₂O₃ diaphragms, paving the way for realization of resonant transducers using such nanomechanical structures for use in applications including gas sensing and ultraviolet radiation detection.     

Parallel Adder Design with Reduced Circuit Complexity Using Resonant Tunneling Transistors and Threshold Logic

Quantum-effect devices utilizing resonant tunneling are promising candidates for future nano-scale integration. Originating from the technological progress of semiconductor technology, circuit architectures with reduced complexity are investigated by exploiting the negative-differential resistance of resonant tunneling devices. In this paper a resonant tunneling device threshold logic family based on the Monostable-Bistable Transition Logic Element (MOBILE) is proposed and applied to different parallel adder designs, such as ripple carry and binary carry lookahead adders. The basic device is a resonant tunneling transistor (RTT) composed of a resonant tunneling diode monolithically integrated on the drain contact layer of a heterostructure field effect transistor. On the circuit level the key components are a programmable NAND/NOR logic gate, threshold logic gates, and parallel counters. The special properties of MOBILE logic gates are considered by a bit-level pipelined circuit style. Experimental results are presented for the NAND/NOR logic gate.     

Zutrittskontrolle mit Gesichtserkennung

Firmen&ProdukteDehn Austria

überspannungs-schutz in der Telekommunikation     

Design and analysis of UW-OFDM signals

Unique word-orthogonal frequency division multiplexing (UW-OFDM) is a novel signaling concept where the guard interval is implemented as a deterministic sequence, the so-called unique word. The UW is generated by introducing a certain level of redundancy in the frequency domain. Different data estimation strategies and the favourable bit error ratio (BER) performance of UW-OFDM, as well as comparisons to competing concepts have already extensively been discussed in previous papers. This work focuses on the different possibilities on how to generate UW-OFDM signals. The optimality of the two-step over the direct approach in systematic UW-OFDM is proved analytically, we present a heuristic algorithm that allows a fast numerical optimization of the redundant subcarrier positions, and we show that our original intuitive approach of spreading the redundant subcarriers in systematically encoded UW-OFDM by minimizing the mean redundant energy is practically also optimum w.r.t. transceiver based cost functions. Finally, we derive closed form approximations of the statistical symbol distributions on individual subcarriers as well as the redundant energy distribution and compare them with numerically found results.     

Managing diet quality for Cheddar cheese manufacturing milk. 1. The influence of protein and energy supplements.

The effects of supplementing cows' diets with protein and energy on milk composition and the composition and yield of Cheddar cheese were investigated. This research addresses the problems of seasonal reduction in the capacity of cheese curds to expel moisture as observed in parts of south-eastern Australia. Milk was collected from cows offered a basal diet of silage and hay supplemented with different sources and levels of dietary protein and energy. The protein supplements were sunflower, canola, cottonseed meal and lupin, and the energy supplements were maize grain, oats, wheat and barely. This milk was used to manufacture Cheddar cheese on a pilot scale. Cheese moisture content was dependent on the source and level of dietary protein and energy. Milk from cows offered the lupin protein supplements and wheat energy supplements consistently produced cheese with a lower moisture content and moisture in fat-free matter. Milk from these supplemented diets had increased casein concentrations and higher proportions of alpha S2-casein than milk from the poor quality control diet. Cheese yield was directly related to the total casein concentration of milk, but was not influenced by differences in casein composition. Supplementing the cows' diets increased the inorganic P, Mg and Ca concentrations in milk. A low inorganic P concentration in milk from cows offered the control diet was caused by a low intake of dietary P. These findings showed that changes in the mineral and casein composition of milk, associated with diet, could influence the composition of Cheddar cheese.