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The more number of minimal cut sets, the more dangerous system [5].
If the basic events in any one of the minimal path sets don’t occur, the top event wouldn’t occur; the more number of minimal path sets in fault tree, the more means of preventing accidents [5].
Through analysis of the propellant combustion / explosion fault tree, the order of the 8 basic events’ structure importance is as follows: I(X1)=I(X2)=I(X3)=I(X4)=I(X5)=I(X6)=I(X7)=I(X8) =0.125 Through analysis of the AP wastewater spill fault tree, the order of the 8 basic events’ structure importance is as follows: I(X9)=I(X10)=I(X11)=I(X12)=I(X13)=I(X14)=0.167 (4) Discussion From the minimum cut sets / path sets of the two fault trees, it can be known that the numbers of the minimum cut sets are respectively 8 and 6, and the numbers of the minimum path sets are 1, which means 8 / 6 ways can lead to propellant combustion / explosion / AP wastewater spill but prevention approaches are only one.
Component content analysis of waste grains and waste water generated by high pressure water-jet cleaning HTPB propellant [J].

Introduction It is one of the urgent problems to be solved in the current iron ore processing industry of separation and purification of fine grained refractory ores.
(2) In Eq.2, I is the current flows through the inductor, B(k) and ν(k) respectively are magnetic induction intensity and volume of the element k, μ0 is the air permeability, and n is the total number of subdivision elements.
When respectively changing of the self-inductance coefficients including inner diameter, outer diameter, height, and number of turns of the inductance coil, changing rules of the output inductance values of the iron ore core inductive sensor is analyzed and summarized.
It is found that the inductance value increases following increasing of the inner diameter, the outer diameter, and the number of turns of enamelled wire; When the coil height is less than 30mm, the inductance value decreases with increasing of the height; When the height is less than 40mm and more than 30mm, the inductance value increases with increasing of the height; When the coil height is more than 40mm, changing of the inductance value becomes smaller and tends to be constant.
Table 2 Structure size parameters configuration of the iron ore core inductance sensor (/mm) Number of turns Height Inner diameter Outer diameter Enameled wire diameter 1000 20 16 66 0.52 Summary The properties of the magnetite are expound, theoretical method of calculating the inductance value of the iron ore core inductance coil of the iron grade sensor is given.

In fact, has a number of cloud computing security problems occur, such as in March 2009, Google leaking out the large number of users files event occurs.
Summed up, data security risks of the major cloud computing services have the following several aspects: 1) Data transmission security Normally, the enterprise data center to save a large number of enterprises and private data, these data are often represents the core competitiveness of enterprises, such as the enterprise customer information, financial information, the key business process and so on.In cloud computing model, enterprise data through the network to the cloud computing services processing, faced several problems: one is how to ensure the enterprise data in network transmission process strictly encryption, guarantees the data even if the theft can not restore; the two is how to ensure the cloud service providers in the receive data when the enterprise confidential data leak out; three is in the cloud computing services department store, how to ensure access to the user through the strict certification authority and legitimate access to the data, at the same time to ensure
In the implementation of the audit process, also should guarantee the audit institution does not leak related enterprise's sensitive number.
Attribute-Based encryption for tine-grained access control of encrypted data[M}.

So the sample numbers were designated as a, b respectively Surface morphology and phase analysis.
In addition, it also can be seen that a large number of bright grain precipitated on the surface of coatings.
It may be the reason of active points were closed by a large number of bubbles on the surface due to the greater membrane resistance of anode prepared by surface nitriding, then leading to chlorine evolution mechanism has been changed [10].
In potential range of 0.2 ~ 1.2V, the surface of the coating did not happened hydrogen or chlorine evolution reaction, so the coating was considered in the electric double layer region which can better reflect the number of active points of anode coating on the surface [12].

Introduction The 3C-SiC polytype is attractive in a number of applications, but bulk crystal growth of cubic SiC turned out to be rather difficult.
While hexagonal polytypes, in particular 6H-SiC and 4H-SiC, passed through a significant evolution in terms of crystal diameter enlargement and defect density decrease, 3C-SiC still shows a number of problems to be solved due to its metastable nature.
To increase the number of experiments, the wafers were divided into 4 equal segments.
To evaluate the occurrence of so called double position grain boundary defects in 3C-SiC, the domain size was determined using electron backscatter diffraction (EBSD) at an angular sample tilt of 70° (EBSD-Detector: Oxford Nordlys) as well as optical microscopy in transmission mode.
Results and Discussion In order to study the effectiveness of polytype switch from 6H-SiC to 3C-SiC when 3C-SiC domains start to form, we have carried out a number of experiments where we varied absolute growth temperature, temperature gradient, growth pressure, application of tantalum as carbon getter, substrate orientation and substrate pre-treatment.

So the large number of Fe ions diffusion outward and are oxide by high temperature water vapor, and then formed outside oxide layer [4]. 2) With further oxidation, the diffusion of large number Fe ions from metal matrix to outside layer caused the Fe depletion and Cr enrichment.
In the outside layer，the main element atomic number ratio of Fe:O is 1. 27～1.30，which is near 4:3，and in the inner oxide layer，the atomic number ratio of (Fe,Cr):O is 1. 27～1.26，which is near 4:3.
Grain size of the P91 steel steam oxidation properties [J], Corrosion Science and Protection Technology, 2008,03:162-165

Table 1 The spraying parameters of the NiCrAlY coatings Serial number Current (A) Voltage (V) Spray distance (mm) Feed interval(mm) Primary gas (Ar),slm Secondary gas (H2),slm Scan speed (mms-1) Beam size (mm) Laser power (W) L1 470 65 100 2 60 2 290 Φ 3 1500 L2 470 65 100 2 60 2 290 Φ 3 2000 L3 470 65 100 2 60 2 290 Φ 3 2500 L4 470 65 100 2 60 2 290 Φ 3 3000 Microstructural characterization and the porosity of NiCrAlY coatings were studied using an optical microscope.
When the laser power arrived at 2500W, some pores were still observed, nevertheless their number was largely decreased and the coating achived metallurgy bonding entirely which can be seen in fig.1c.
(Fig.2) a） (Fig.3) a） Fig.2 Porosity of the LHPS NiCrAlY coating with different laser power (L1)1500W;(L2)2000W;(L3)2500W;(L4)3000W Fig.3 Micro-hardness of the LHPS NiCrAlY coating(L1)1500W;(L2)2000W;(L3)2500W;(L4)3000W Table 2 The bonding strength of the coatings Coating number Loading（KN） Bonding strength （MPa） 1 2 3 L1 15.88 20.84 21.78 33 L2 24.32 21.86 21.63 48 L3 41.26 45.71 42.65 87 L4 10.34 8.63 9.51 20 Table 2 gives the bonding strength of the LHPS NiCrAlY coatings with the laser power of 1500W,2000W,2500W and 3000W respectively.Firstly, with the increasing of the laser power from 1500W to2500W, the coatings’ bonding strength are rising gradually,and this is because the laser power assist the plasma beam to melt the spraying powders and coatings farther in the LHPS processing and the spraying powders could not be melted adequately until the laser power arriving at 2500W(which can be seen in fig.5).
（d） a） （a） a） （c） a） （b） a） Fig.4 Photographs of the corrosion area of the coatings after 96 hours of NSS test with different laser powers (a)1500W(b)2000W(c)2500W(d)3000W Table 3 The corrosion area of the surface coating after 96 hours of NSS test Coating number L1 L2 L3 L4 Corrosion area (the proportion to the whole coating) 1/2 1/3 one point 2/3 （b） a） （a） a） （d） a） （c） a） Fig.5 SEM configuration of the spraying powders on the surface coating depostited by diffferent laser power in LHPS processing (a)1500W (b)2000W (c)2500W(d)3000W The Fig.5 gives the SEM configuration of the spraying powders on the surface coating deposited by diffferent laser power in LHPS processing and which further demonstrates that how the laser powers affect the coatings’ microstructures.We can see that the melting state of the powders are changed following different laser power, when it is 2500W, the spraying powders can be melted sufficiently
When the laser power is lower than 2500W, for example the 1500W and 2000W, many big grains of unmelted or mid-melted powders can be seen on the surface coating and which make the coating’s microstructure loose and exsit poor bonding strength(as is shown in fig.5a,b).This is because the laser density is too low to melt the spraying powders sufficiently, the laser irradiation area became solidify rapidly and many cracks and big pores are formed in the coating(fig.1 a,b).

On the other hand, the magnetizing inductance is also proportional to the square of the number of turns in the secondary, N2.
(7) For the tests in the field, two units of a steel-oriented Silicon grain "C" type core have been manufactured, weighing about 13 kg and with section area equal to 50 cm2.
Figure 10 shows the result of voltage simulation for resistive load of 50Ω, varying the primary current and the number of turns in the secondary.
In the laboratory, it was determined that the optimal number of turns for the total load (included the electronics and the capacitances) of the prototype is 15 turns with the double core CT.
Simulation for the optimal number of turns for maximum power extraction Figure 11.

HC mainly comes from unburned fuel, disaggregate-tire fuel molecules and a small number of intermediate products of oxidizing reaction.
One is EGR+grain reduce technology the other is SCR technology.
Project Technology Performance Index and Standard Number Program Name Technical Index Actual Prototype Index 1 Type YCD4B54 YCD4B54-115 2 Pattern Upright, orthostichous, water-cooling, four-stroke, direct injection Upright, orthostichous, water-cooling, four-stroke, direct injection 3 Cylinder type Wet sleeve Wet sleeve 4 Number of cylinder―cylinder bore×distance mm 4―95×105 4―95×105 5 Cylinder center distance mm 116 116 6 Admission method Pressure Inter-cooling Pressure Inter-cooling 7 Displacement volume L 2.977 2.977 8 Rated power kW 85 86.1 9 Rated speed r/min 3200 3200 11 Maximum torque N·m ≥300 305.5 12 Maximum torque speed r/min ≤2200 2200 13 Maximum torque working condition of fuel consumption g/kW·h ≤220 211.0 14 Discharge Accordance with the requirements of the national IV standard Accordance with the requirements of the national IV standard 15 Noise Lw dB(A) ≤115 114 16 Engine fuel consumption ratio % ≤0.3 0.06 Existing Technical Problem and Advice of Improvement The
Acknowledgements This research was supported by Guangxi Scientific Research and Technology Development Project (project number: 11107001-26) References [1] Automobile Engineering Manual Editorial Board, Automobile Engineering Manual (Basic),China Communications Press, 2001-05 [2] Automobile Engineering Manual Editorial Board, Automobile Engineering Manual (Test),China Communications Press, 2001-05 [3] Automobile Engineering Manual Editorial Board, Automobile Engineering Manual (Design), China Communications Press, 2001-05 [4] Automobile Engineering Manual Editorial Board, Automobile Engineering Manual (Manufacture), China Communications Press, 2001-05 [5] Wangyu WANG , Automobile Design (4th edition),China Machine Press, 2007-09 [6] Zhisheng Yu, Automobile Theory,Beijing, China Machine Press, 2000-04 [7] Jiarui CHEN, Automobile Structure (Volume one), Beijing, China Communications Press, 2007-08

Such failure situations are more likely in high-temperature applications ranging from 450°C to 850°C, as operation cycles can sensitize the metal, resulting in precipitation of chromium carbides along the grain boundaries [5], [6].
Both AR and SEN samples were polished to a mirror finish and then underwent electrolytic etching with 0.1% oxalic acid following ASTM E407, etchant number 13a.
Carbide precipitation along the grain boundary was observed in the SEN sample, whereas the AR sample initially displayed no discernible structure.
In contrast to AR sample, SEN sample revealed a number of cracks along with rust layers.
The occurrence of higher-energy AE events suggests the formation of larger cracks, potentially due to multiple crack initiation sites along the grain boundaries.