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Online since: May 2012
Authors: Mikael Östling, Martin Domeij, Benedetto Buono, Reza Ghandi, B. Gunnar Malm, Carl Mikael Zetterling
However, analysis of the base current of the base-emitter diode shows that the degradation of the passivation layer could also influence the reduction of the current gain.
The BJTs with WE equal to 30 and 25 µm show a reduction of around 15% during the first 10 hours, while the BJTs with WE equal to 10 and 6 µm show a smaller reduction during the first three hours and one hour respectively.
Only the device with WE equal to 6 µm shows a reduction between 40 and 60 hours.
This behavior, i.e., the reduction of the collector current, has been detected in all the devices summarized in Fig. 1.
However, the value extrapolated from the measured data is around 1.5, suggesting that the degradation of the lifetime in the base region might be only one of the causes for the degradation of the current gain.
Online since: August 2014
Authors: Caterina F. Carocci, Cesare Tocci, Pietro Copani, Lucia Marchetti
Vulnerability reduction procedures in ordinary urban management.
For each surveyed building, a set of data was collected concerning the walls (material, thickness, presence of inserts different from the traditional ones), the floors (type and material of the structure, presence of pushing roofs) and the staircases, as well as the eventual presence of weak points (as excessive thinning of the walls’ thickness, lack of bonding, cracks and deformations) and strength devices (tie rods, scarp walls, etc.).
In other words, they just define design criteria – and not technical solutions – with the aim to pursue a vulnerability reduction strategy within a conservative approach respectful of the original nature of historical masonry structures.
In the remaining municipal urban area, when interventions are not listed in the restoration and preservation categories, it is mandatory to prepare for each building, before developing the project, a preliminary report that must contain: the collection of data required from the Planning, the examination of the “Seismic City Plan” contents, and the qualitative analysis of the building vulnerabilities.
With the aim of a uniform treatment of data and information, the required reports must follow a purpose-built form set up by the municipality and containing synthetically the most important information as derived from the analyses conducted both in the study here presented and in that realised by the Department of Civil Protection.
Online since: February 2015
Authors: Cheol Sang Kim, Mahesh Kumar Joshi, Hem Raj Pant, Han Joo Kim, Ni Na Liao, Jun Hee Kim, Bishnu Kumar Shrestha, Chan Hee Park
UV-visible spectra showing gradual reduction of 4-NP over different catalyst dose; (a) 0.4 g/L and (d) 1.6 g/L.
The rate of reduction of p-nitrophenol was found to be directly propositional to the dose of the composite.
The peak at 400 nm gradually decreased in the reduction process and finally disappeared at its completion.
Das, Journal of Chemical & Engineering Data, 58 (2013) 3477-3488
Liu, Journal of Chemical & Engineering Data, 56 (2010) 138-141
Online since: May 2015
Authors: R.O. Ocaya
email: ocayaro@qwa.uovs.ac.za Keywords: FPGA, CCD sensor, High speed data acquisition, Spectrometer, MicroBlaze core.
The host interface is high-speed USB for data exchange with high-level environments such as Visual Basic, MATLAB and LABVIEW.
There are various soundcard based oscilloscope and data-logging programs that can also be used for read-out[25].
From left to right: laser, grating, a reduction lens.
Results The spectrometer was calibrated using semi-flash ADC data on 633nm and 635nm (red) lasers.
Online since: July 2007
Authors: Stoyan N. Groudev, Plamen S. Georgiev, Irena Spasova, Marina Nicolova
The present paper summarizes the data obtained during the about 10-year period of such operations and contains the main conclusions based on these data.
Data about the microflora of the wetland are shown in Table 1.
Content of radioactive elements and heavy metals in different plant species from the constructed wetland Typha latifolia Phragmites australis Scirpus lacustris Elements I II I II I II U, mg/kg 28 - 95 ND 12 - 82 ND 12 - 59 ND Ra-226, Bq/kg 35 - 145 ND 35 - 125 ND 23 - 82 ND Cu, mg/kg 55 - 194 7 41 - 140 5 23 - 71 3 Zn, mg/kg 32 - 225 5 64 - 203 7 44 - 114 3 Cd, mg/kg 5 - 23 ND 5 - 18 ND 3 - 10 ND Ni, mg/kg 21 - 100 3 18 - 79 3 14 - 59 3 Co, mg/kg 15 - 71 2 15 - 105 3 10 - 51 2 Pb, mg/kg 12 - 64 5 8 - 54 5 9 - 32 7 Mn, mg/kg 91 - 325 10 44 - 262 8 41 - 154 8 As, mg/kg 6 - 68 3 10 - 59 3 6 - 28 2 Notes: I - Data about plant specimens grown in the wetland; II - Data about plant specimens grown in a wetland non-polluted by radioactive elements and heavy metals.
The microbial sulphate reduction was a function of the concentration of organic monomers dissolved in the waters.
Under such conditions the microbial sulphate reduction still proceeded, although at much lower rates.
Online since: March 2011
Authors: Guan Hua Zhao, Wen Wen Yan
When the number of training samples are large,solvingwill take more time and space.However,increase remembrance algorithm can avoid this problem,its general description is: When there are n samples in training data,given,,,,equation(9),(10) can be written as: (11) (12) (13) When the number of samples in training data increases two,that is to include sample into original training data w,we have: (14) (15) (16) Here,,, is constituted by plus 1 column and 1 row,that is: (17) From equation(14) to equation(16),we can know that,if we know,we can solve the value of ,,.In order not to calculatedirectly,but calculate it
, it doesn't insert all samples as support vector at a time, but increases two training samples in turn by the entropy biggest principle based on the initial training sample data.
Experiment and Result Analysis The origin and selection of sample.These research data of this article are from the CSMAR database,this article chooses 167 listed company of A stock market between 2002 and 2007 as research sample randomly from Shanghai and Shenzhen two stock markets, rejects finance class samples and samples whose data are not entire, and takes these left 152 samples as the final research sample.Thereinto,50 samples are test samples, other 102 samples are training sample.
Preprocessing of target data.This article uses traditional factor analysis method and neighbourhood rough sets reduction method to preprocessing pre-election indexes respectively.
It uses reduction algorithm based on neighborhood rough set to select targets on the basis of standardizing the 31 candidate target.In order to compare with the classical rough set method, we introduce CART classification learning algorithms in the experiment,the specific steps are:for the classical rough set attribute reduction,first use Equal frequency binning algorithm of Rosetta software to discretize data,then use Johnsonreducer algorithm to attribute reduce discretized data;for neighborhood rough set attribute reduction,use forward greedy numerical attribute reduction algorithm of MATLAB 7.0 to attribute reduce data.Because the attribute reduction number is influenced by the size of neighbourhood δ, this article use 0.1 as steps of δ, δ ranges from 0.1 to 1, and the results shows that, whenδ = 0.9,the classification precision is optimal(get the highest classification precision by the least number of attributes).Table 2 shows the attribute reduction circumstances of the two methods
Online since: September 2013
Authors: Ke Wang, Jian Tao Liu, Wen Bo Mao
P_base express the base load of TOU, that is the original data of IEEE39bus model.
(3) In Eq.3, P_RTP is the load power; P_base is the original data in IEEE39bus model; Pri_rt is real time price; Pri_base is the average price of historical data.
In day-ahead part, we calculate OPF 96 times, to get the base data (OPF output).
Then, the DR parameters are set according to these base data.
In daily part, we calculate OPF for another 96times, to get the DRs operation data.
Online since: February 2013
Authors: Mei Song, Zong Yuan Lin, Yan Qing Zuo, Tao Chen
China has made carbon reduction commitments ​​in the Copenhagen Climate Conference, which is that by 2020, China's carbon intensity is 40-45% lower than 2005.
Basic data.
Using the total energy consumption amount data of the third industries in China's in 2004-2011 as the basic data of the forecast, the data are from the 《China Energy Statistical Yearbook 2009-2012》.
Table 3 shows the CO2 emission and carbon intensity prediction in 2015 and 2020 and analysis reveals that China's current energy consumption structure cannot achieve the 2020 carbon reduction target.
Therefore, we should optimize China's energy structure from two aspects of energy saving and emission reduction.
Online since: October 2011
Authors: Zhi Wei Wang, Xiang Jing, Xiao Hong Yang
Problems and Countermeasures of Air Conditioning Systems in Internet Data Centers in Xi’an city Xiaohong Yanga, Zhiwei Wangb, and Xiang Jingc Xi’an University of Architecture & Technology, Xi’an, Shaanxi, 710055, P.R.China a776995609@qq.com, bWzhiwei-atu@163.com, c410419290@qq.com Keywords: air distribution, high temperature alarm, system energy efficiency, internet data center, countermeasures Abstract.
Site investigation on air conditioning systems (ACS) in three internet data centers (IDCs) in Xi’an city was conducted, the relative data used for issues analysis was obtained from on-site testing of temperature field and velocity field in IDCs and online working meter on power distribution box of ACS and computer cracks, the field investigation found that there were three main problems: high temperature alarm of larger power electronic components in computer cracks; irrational air distribution around computer cracks; and not high energy efficiency of ACS.
They include the cold and hot air stream mixing, nonuniform of static pressure in underfloor plenum chamber, and air temperature rise of jet flow in upper air supply mode etc., and lead to the energy efficiency reduction of ACS.  
The improvement measures of system efficiency will be taken in three aspects: 1) a rational air distribution should be designed according to different demand of microthermal environment of CRs in IDCs; which involves air supply pattern selection and individuation demand satisfaction etc.; 2) for air cooling type of condenser with water spray, based on testing data from field or manufacturer, the optimal time of water spray and interval of twice spray can be determined for best heat exchange effectiveness; 3) by adding an independent fresh air system, outdoor air natural cooling resource can be fully used in transitional seasons and winter, thus electricity power consumption of refrigerator will greatly decreased during corresponding period; 4) by using water loop heat pump system, a great deal of heat from CRs in IDCs can be absorbed and transferred into a zone of heating demand or as a heat source for hot water supply in IDC building.
C&AC.21 (2007), p. 105-107 [4] Xiang Jing: Test and research on the Air-conditioning system in Internet Data Centers.
Online since: June 2012
Authors: Mahmoud M. Tash
Each data point on the plots of hardness measurement represents the average of at least six readings.
Each UTS data point represents the average of at least three values.
Hardness increases by 20% as reduction ratio increases from 1.11 to 1.29.
Note that an increase in reduction ratio will also be accompanied by a reduction in impact (Charpy) toughness, Figure 1.
Similarly, the yield strength is reduced from 834 to 309 N/mm2 (reduction of 63%) and from 649 to 468 N/mm2 (reduction of 28%) for the annealed and normalised specimens, respectively.
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