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Accurately evaluated the bearing capacity characteristic value of red clay is of great important to make use of high strength. Based on analyzing current specifications methods to determine the bearing capacity eigenvalue of red clay foundation, it is found that deficiencies are the limitation of application, the disturbance of determining indexes such as water content, liquid limit, plastic limit and compression modulus, and even lack of reflecting effects of the stress level, the shape and failure mode of subgrade. To deal with these shortcomings, a method for determining the bearing capacity of red clay foundation in view of the stress level was proposed. This method adopts tangent modulus that can reflect different depth of stress levels instead of compression modulus to calculate the curve of load and settlement under the size of plate, and utilizes the modified Vesic formula to consider the influence of the shape and failure mode of ground to calculate the ultimate bearing capacity as major parameter of different depth of stress level calculation. The indoor shear strength index can be used to calculate the ultimate bearing capacity if there is no plate load test. According to the characteristic of the settlement and load curve, the intrinsic value of subgrade bearing capacity is achieved using the plate load test method. Verified through an engineering cases, the characteristic value of the bearing capacity obtained using this method is more consistent with that obtained by the plate load test, meanwhile more flexible in the actual application. It also can be used for reference to determine the characteristic value of bearing capacity in other red clay area.

This paper introduces a novel ultra wideband self mixing frequency conversion system. The final output if signal can remain unchanged with the change of RF signal in a certain frequency range. The realization method is to compress the ultra wideband signal 0.8-20 GHz into the narrow-band IF signal through the folding filter bank. The IF signal is divided into two channels through the power divider: the first LO signal is generated by mixing the IF signal of one channel with the point frequency, the first IF signal is generated by mixing the IF signal of the other channel with the first LO signal after delay, and the second IF signal is generated by mixing with the second LO signal, because the second IF signal does not change with the external signal, so Realize the self mixing frequency conversion function of fast search. It has super fast convergence function and can provide fast guidance function for detection system.

This paper introduces a C-band 1KW power amplifier design based on waveguide magic T synthesis. The high isolated Gisil power distributor and the low loss and high power rat race power distributor are cascaded to complete the eight channel high power signal distribution. Finally, super power output signal is achieved by eight channel waveguide magic T synthesis. This paper solves the problem of multi-channel signal distribution and synthesis under high power. It has the advantages of high synthesis power and efficiency, which can be widely used in the field of super power synthesis.

Metallic lithium, with super high theoretical specific capacity, enjoys great potential as an anode for rechargeable batteries. However, safety issues caused by lithium dendrite growth as well as limited cycling life restrict its practical application. Herein we validate that the application of a new dual-salt electrolyte composed of Lithium difluorophosphate (LiPO2F2) and lithium bis(fluorosulfony)imide (LiFSI) in the same proportion enables the improved long-term cycling performance along with high coulombic efficiency for lithium metal batteries. With 1 M LiPO2F2 and 1 M LiFSI in 1,2-dimethoxyethane as the electrolyte, a Li/Cu cell can be cycled at 1 mA for more than 300 cycles with a deposited capacity of 1.0 mAh. It also displays that a homogeneous and dendrite free solid electrolyte interphase layer is generated on the Cu electrode, which can be ascribed to the favorable stability of LiPO2F2 and high ionic conductivity of LiFSI. These results deliver perceptions for the advancement of high-performance lithium metal anode.

Cloud-based content distribution networks (CDNs) consist of multiple servers that consume large amounts of energy. However, with the development of a cloud-based software defined network (SDN), a new paradigm of the virtual content distribution network (vCDN) has emerged. In an emerging cloud-based vCDN environment, the development and adjustment of vCDN components has become easier with the aid of SDN technology. This transformation provides the opportunity to use vCDNs to reduce energy consumption by adjusting the scale of the vCDN components. Energy costs can be reduced by deactivating the commercial servers carrying the software components of the vCDN, such as replica servers, the firewall or routers. In addition, the CDN requires a high service level agreement (SLA) to respond to clients’ requests, potentially consuming large amounts of energy. In this research, we focus on the issue of the energy savings of a CDN in a cloud computing environment while maintaining a high quality of service (QoS). We propose an approximate algorithm termed max flow forecast (MFF) to determine the number of software components in the vCDN. Additionally, we use a real traffic trace from a website to assess our algorithm. The experimental results show that MFF can produce a larger energy reduction than the existing algorithms for an identical SLA. We fully justify our research as a good example for the emerging cloud.

Paichongding (IPP) is a neonicotinoid chiral insecticide with independent intellectual property in China. IPP application can increase crop yield, and also lead to insecticide residue and pollution in soils, which will affect microbial population and community composition in soils. In this study, four different types of soils were employed to inquire into the impact of IPP on eukaryal community and species-group through pyrosequencing of 18S rRNA gene amplicons. Fungal population differed in different soils at different days after IPP treatment (DAT). Eukaryal community species in CK (control check) groups were more rich than that with Paichongding sprayed at 5 DAT, while eukaryal species in CK soils at 60 DAT was relatively slight. Shannon’s H’ analysis indicated fungal species in CK soils were also higher at 5 DAT and relative lower at 60 DAT, except in soil C. There are also differences in the phyla and genus levels of the eukaryotic communities in the soil. After IPP application, the relative abundance of Nectriaceae increased 3–4 times in soil C. In soil F, Phaeosphaeriaceae increased to 57.3% at 5 DAT. The genus of Guehomyces, Aspergillus and Alternaria increased from 3.1 to 9.7, 1.1 to 4.6, 1.5 to 6.7% in soil H, respectively.

Content distribution networks (CDNs) play an important role in distributing content between end users and servers because they can effectively reduce response delays and bandwidth consumption by deploying sets of servers close to end users for service provision. A remaining challenge to CDN deployment is how to efficiently place the replica servers while guaranteeing the quality of service (QoS). As a newly emerging technology, network function virtualization (NFV) facilitates the use of network function software and enables the deployment of different network functions on networked commercial servers. Virtual CDNs are among the most relevant cases that could benefit from NFV. In this paper, we study the problem of efficiently deploying replica servers (middle boxes) in cloud data centers via NFV. We propose an approximation algorithm based on spectral clustering theory to solve the replica server placement problem within an NFV environment. We conduct simulations using local and large-scale data centers to evaluate the performance of our proposed algorithm. The simulation results show that our algorithm achieves lower deployment costs and improved data fusion while optimizing nodes, services and data processing.