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DC Distribution in Data Centers.
Data centers have been growing at a rate of 20% annually over the past decade.
With increasing cloud computing and big data, it is expected that data centers alone will consume 10% of the total electricity by 2020.
Currently the majority of data centers operate primarily off of a 12 V bus system internal to the rack.
With the rapidly expanding need for data servers these inefficiencies have compounded and today represent significant levels of power consumption.

Al-Mg-Si alloy is cryorolled to 50% and 75% reduction at -196°C and also at room temperature.
The total thickness reduction was achieved by means of multiple passes with about 1% reduction per pass and after each pass, the cryorolled sheets were again maintained in cryogenic medium for 2 min before further reduction.
In a similar manner, the RTR and LNR samples rolled for 75% reduction exhibited a hardness increment of 2% and 4% over the corresponding samples rolled for 50% reduction.
Thus, with an increase in the percentage of rolling reduction, an increase of hardness was observed.
Table 2 Electrochemical data for the alloy in all the cases in 3.5 wt% NaCl solution Processing Condition Ecorr (mV) Icorr (µA/cm2) Annealed & solutionized -730 2.09 RTR 50% -689 3.81 LNR 50% -664 5.87 RTR 75% -704 3.28 LNR 75% -682 1.20 4.0 Conclusions: It can be concluded from the present investigations that, the process of rolling adversely affected the corrosion resistance of Al-Mg-Si alloy.

The nanocrystalline WC-Co bulk material with a relative density of 98.5% was prepared by combing in-situ reduction and carbonization reactions and spark plasma sintering method.
The WC-Co composite powder was fabricated by in-situ reduction and carbonization reactions [8].
The data is not stable as the penetration depth is not deep enough (for example less than 300nm).
As the penetration depth is larger than 300nm, the contact area of the indentation is large enough to eliminate the up negative effects to the precise of the measured data, especially to cause more WC grains and Co phase to deform together.
Conclusion The nanocrystalline WC-Co bulk material, with a relative density of 98.5% and a mean grain size of 90nm, was prepared by combing in-situ reduction and carbonization reactions and spark plasma sintering.

Test shows that without affecting the work performance of pneumatic tools, the muffler can be 10-12dB noise reduction, which is worthy applying.
Finally they blow out from the dense holes in another port , causing quadratic noise reduction[4].
After substituting the data above ti formula (7), we can obtain the muffler length L=0.1m Shell material selection Considering the using continence and easy manufacture, the shell should be made of light material and the plank should be some thin material .Thus could lighten the quality and save materials .Thin material will vibrate under the impaction of gas current, which could consume energy and low down noise .In light of the reasons above, selecting 1mm galvanized steel plate as shell material is suitable.
Substituting all the data above to formula (9),and (10),we can work out waterspout，16.59mm waterspout in admitting port ,thus the total resistance loss in admitting port is 19.97mm waterspout；Also waterspout ，mm waterspout in exhausting port and the total resistance loss in it is 12.77mm waterspout.
Noise reduction with perforated three-duct muffler components

Snowstorm risk assessment in China based on environment & disaster monitoring and predicting small satellite Chao Lv 1,2, a, Huili Gong 1,b, Zhiheng Wang 3,c 1College of Resource Environment and Tourism, Capital Normal University, Beijing 100048, China 2 Computer Information Center, Beijing Institute of Fashion Technology, Beijing 100029, China 3Academy of Disaster Reduction and Emergency Management Ministry of Civil Affairs & Ministry of Education, Beijing 100875, China alcrabbit@163.com, bgonghl@263.net, cwzh19831221@163.com Keywords: Snowstorm; risk assessment; fuzzy math; small satellite Abstract.
After the massive experiment monitors and the contrast confirmation with the disaster situation data in National Disaster Reduction Center, the model forecasting result and the disaster situation statistical data have good uniformity from the space position and the risk degree.
According to the historical case data, the three evaluation factors are analyzed.
Assessment result by predictive model Validation and Conclusion The model is used in a short-term evaluation of pastoral snowstorm disaster risk from January 1st to February 28th of 2010, for model validation by comparing the model predictions with the real data set from National Disaster Mitigation Center.
As the results of this study indicate, the assessment outcome from January to February coincides well with the statistical data in terms of space location and risk level.

Basing on data analysis we determine three stages necessary for designing radiation models of semi-conductor devices: · at the first stage we are to determine relations between a device parameters and electrophysical, optical, geometrical and other properties of the starting substance; · at the second stage we study changes of properties of the starting substance and the device parameters when subjected to radiation and find out regular principles which can describe these changes; · the third stage consists of designing a radiation model basing on the determined principles.
Research data obtained under radiation exposure in passive powering mode, i.e. without operational current, were used for making the LED radiation model.
Fig. 1 Watt-ampere characteristics and volt-watt characteristics under irradiation by fast neutrons: 1 – area of strong injection of electrons; 2 – area of average injection of electrons; 3 – area of low injection of electrons; arrow - boundary between strong and average injection of electrons; light symbols – first stage; dark symbols – second stage; symbols – experimental data , the line - calculation of the established relations First of all we will consider initial LED characteristics.
Fig. 3 Power reduction of radiation under exposure to fast neutrons at different values of the operating current: symbols - experimental data, line - calculation on the established relationships Fig. 3 shows that the reduction of radiation power under exposure to fast neurons undergoes three stages: · at the first stage it is caused by radiation restructuring of the initial defects, which is proved by the fact that the damage ratio does not depend on the exposure level and the power reduction process is more active as the exposure level grows; · at the second stage it is caused by introducing defects of purely radiation nature, damage ratio being dependent on the first stage; · at the third stage transition into low electron injection mode takes place, radiation power does not depend on working current value and does not change when fast neuron fluence further grow.
It can be seen from Fig. 3 which compares the calculated dependences to the experimental data.

The carbon reducers are not only a source of carbon as a substrate of the silica reduction reaction, but also play an important role by acting as a gas filter at the upper zones in working space of the ferrosilicon furnace.
Introduction Ferrosilicon smelting is a continuous carbothermic silica reduction process carried out in the submerged arc furnaces with the Søderberg self-baking electrodes.
Industrial observations and laboratory testing indicates that properties of raw materials have a significant influence on the course of the carbothermic silica reduction process.
Data on chemical composition and vitrinite reflectance index R0 for several hard coals from different mines are shown in Table 1.
Observations of the 20 MVA ferrosilicon furnaces have shown that utilization of reducing mixture with composition 2* instead of mixture 1* (Table 2) influenced on reduction in the electric energy consumption for about 2.5 %.

We use the tax survey data of the central treasury, combine with the trajectory and evolution path of China's private economy, introduce a non-parameter DEA method to calculate the Malmquist index and analyze the quality of tax sources and the level of total factor productivity of private enterprises in the post financial crisis era.
Design for the Study Sample selection and data sources We select the research sample from all private enterprises in three industries (summarized by the various sectors) from 2009 to 2011.
All the data are from the national tax survey data tables of the year.
Vigorous tax policy to develop and support the tertiary industry According to the statistical data in this paper, under the same conditions the tertiary industry creates more revenue and total profits and taxes, while the number of labor is far less than in other industries.
The “tax-based type” of tax reduction includes accelerated depreciation, tax deductions, investment credits, loss carryforwards, deferred payments and so on.

Data Processing and Classification Results Using the Suzhou 2000 ETM+ and 2009 TM images as data sources, while collecting the Suzhou 1:500 cadastral map, the second land survey 1:10000 land-use map, urban land-use general planning map.
Tab.2 Land use type transition matrix km2 and transition probability matrix in Suzhou in 2000-2009 2000 2009 construction land cultivated land wood land water body construction land 35.23 (0.82) 5.27 (0.12) 0.80 (0.02) 1.44 (0.03) cultivated land 27.79 (0.42) 32.81 (0.50) 3.95 (0.06) 1.72 (0.03) wood land 2.53 (0.48) 1.82 (0.34) 0.55 (0.10) 0.41 (0.08) water body 1.94 (0.40) 0.52 (0.11) 0.27 (0.05) 2.18 (0.44) Note: Figures in brackets data for the transition probability matrix.
The land use consumption reduction degree means the actual consumption level of a certain land use type within per unit time[4], its expression is Eq.3.
Through calculated, Suzhou in 2000-2009, the land use consumption reduction degree of each land type was in Tab.3
Based on the Suzhou urban land use data in 2000, in Matlab 7.0, taking the step size n = 9, K = 1, 2, 3 and 4, using the 2000 ~ 2009 land use type transition probability matrix (Tab.2) for Markov prediction, and separately calculated the Suzhou urban land use (Tab.4) in 2009, 2018, 2027 and 2036, then analyzed the prediction results and the remote sensing image interpretation results in 2009, to test the consistency of the prediction result and the actual result.

Firstly, the simulation results are compared with experimental data from a reference to verify the usefulness of the simulation.
To verify the validity, the simulation performed under the same conditions as experiment is compared with experimental data in terms of forming force.
In phase 1, the simulation results are compared with the experimental data to verify the validity of the simulation results.
Fig. 2 shows the experimental tool for the sheet metal extrusion process, and an in-house developed data acquisition system is established to measure the force-stroke curve.
The data acquisition system is based on the electrical measuring method, in which the force is measured by sticking a full bridge type of positioning strain gauges on the punch and a displacement transducer is used to collect the corresponding stroke information simultaneously.