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In IaaS Cloud, different mapping relationships between virtual machines (VMs) and physical machines (PMs) cause different resource utilization, so how to place VMs on PMs to reduce energy consumption is becoming one of the major concerns for cloud providers. The existing VM scheduling schemes propose optimize PMs or network resources utilization, but few of them attempt to improve the energy effciency of these two kinds of resources simultaneously. This paper proposes a VM scheduling scheme meeting multiple resource constraints, such as the physical server size (CPU, memory, storage, bandwidth, etc.) and network link capacity to reduce both the numbers of active PMs and network elements so as to finally reduce energy consumption. Since VM scheduling problem is abstracted as a combination of bin packing problem and quadratic assignment problem, which is also known as a classic combinatorial optimization and NP-hard problem. Accordingly, we design a two-stage heuristic algorithm to solve the issue, and the simulations show that our solution outperforms the existing PM- or network-only optimization solutions.

This paper deeply analyzes the data which is closely related to the fuel efficiency in the production database of the airline transportation. It verifies that quadratic polynomial regression model is the best fitting fuel efficiency model after many experiments. It constructs the quadratic polynomial regression model of the fuel efficiency and derives the model's expression using the least square method. And, an example shows the rationality of the model, and better results of testing. Above all, it obtains the influences’ degree of energy-saving and emission-reducing measures in civil aviation to the fuel efficiency, and provides a good theoretical support for further optimization of energy-saving and emission-reducing measures.

It is important for mobile robot to match features from scenes under wide baseline views. Wide baseline matching is one of the difficult problems in feature matching because large variation between the image appearances occurs due to illumination and viewpoints, especially on non-planar and less-textured scenes. In this paper we propose a method of feature matching under large separate views, which is based on the multiple hypotheses about the local transformation and multiple routes propagation. Given a single initial correspondence and the local affine transformation between the neighborhoods around them, the proposed method can supply more stable and accurate matches under wide baseline views. The matches can be propagated adaptively into the regions where the local transformations differ from the initial one. The experiments with real data show that the proposed method achieves the state-of-the art performance among match propagation algorithm.

For the aviation industry, reliability is bound up with personal safety and economic efficiency. Aircraft reliability data is an important indicator of measuring its running quality. Based on the research of the fault phenomenon and causes and the distribution of component fault, put forward the concept of "directional fault subject" and" fault subject with smooth distribution". For the "directional fault subject ", determine the fuzzy membership by the extent of directivity. The method is introduced to fault diagnosis of the aircraft system. According to the routine maintenance and the function characters, divide the aircraft system reasonably. The fault diagnosis and initial reliability fusion in the component-level will be carried out mapping and fusion step by step, establish a mathematical model of aircraft reliability based on fault diagnosis.

Ant colony algorithm is an efficient intelligent algorithm to solve NP hard problem. This paper presents a parallel computing solution based on General Purpose GPU (GPGPU) to solve Traveling Salesman Problem (TSP) with Max-Min Ant System (MMAS). The experimental result shows it is more efficient than pure CPU computing.

The structure of VHF (very high frequency) air-ground datalink and communication protocols are introduced, and the framework of VHF air-ground datalink communication protocols is analyzed. Relationship between ARINC specifications is analyzed comprehensively and the message format conversion between protocols is given. The model of data communication and messages conversion based on air-ground datalink is abstracted. Research on the framework and transformation flow of communication protocols establishes a steady base for the further application of VHF air-ground datalink messages in the civil aviation field.

A generalized exponential spectrum model is derived, which considers finite turbulence inner and outer scales and has a general spectral power law value between the range 3 to 5 instead of standard power law value 11/3. Based on this generalized spectrum model, a new generalized long exposure turbulence modulation transfer function (MTF) is obtained for optical plane and spherical wave propagating through horizontal path in weak fluctuation turbulence. When the inner scale and outer scale are set to zero and infinite, respectively, the new generalized MTF is reduced to the classical generalized MTF derived from the non-Kolmogorov spectrum.