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Therefore, according to the new countryside residence construction request, unifying the Henan Province sentiment and the present countryside residence construction situation, people make some improvements and transformation to the traditional flat roof, expecting to form technical and economical reasonable feasible roof structure technology in the new countryside residence construction. 2 The flat roof problems and analysis of the reasons For asphalt parent metal waterproofing material used on flat roof roofing waterproof layer, because of such outdoor synthesis factors such as the sunlight radiation, the cold hot alternation and so on, the asphalt oil and the resin featherweight component will change into the great molecular weight asphalt nature component, asphalt nature component gradually increases, reducing the plasticity of the bituminous material, increasing brittleness, thus causing the roofing waterproof layer aging embrittlement and the roof leakage.
When the roof building enclosure interior has the condensation or the roofing waterproof layer aging bursts, and when roofing water leakage permeates heat insulating layer, which will increase the roof insulation material moisture content, the roof heat preservation heat insulation ability and the energy conservation effect will be reduced. 3 Prefabricates the trough board flat roof mechanical design “USD” roofing developed by overseas researchers, although, may, theoretically, slow down the traditional roofing waterproof layer material component from the progressively changing aging, in practice and in the process of application, this structure procedure proposed both the waterproofing to the thermal insulation material and the durable dual request.
Because the roof leakage is generally realized by permeating through the structure board between board seams and affects indoor, this structure causes a certain height between the structure board (150mm), even if the layer of draining water presents crack, the roof leakage will not pour into the seam, thus achieving the effect of the roof preventing leakage itself.
The reinforced concrete prefabricated groove plate flat roof structure Table 1 Reinforced concrete prefabricated groove plate roof structure and material properties Tectonic level Material name Laminate Thickness (mm) Coefficient of thermal conductivity (W/mžK) Coefficient of thermal storage W/m2žK) Thermal resistance (m2žK/ W) Structure layer Reinforced concrete groove plate 150 1.74 12.4 0.086 leveling blanket compo 20 0.93 11.37 0.022 insulation Different choices leveling blanket compo 20 0.93 11.37 0.022 waterproof layer SBS modified asphalt coil 3 0.17 3.33 0.059 4 Flat roof precast groove plate thermal performance analysis 4.1 Roof computation model of palisade structure The Henan Province occupies five geographic latitudes from north to south, and outdoor average air temperature of the hottest and coldest months of typical areas through years is shown in table 2[6].
(6) Table 5 Thermal insulation material selection and hot working target Material name Key property request Thermal conductivity predicted value (W/mžK) Regeneration coefficient predicted value(W/m2žK) Coefficient of thermal conductivity (W/mžK) Coefficient of thermal storage (W/m2žK) Compressive strength (MPa) Dry weight density (kg/m3) Cement inflated pearlite board 0.16 2.49 ≥0.3 400 0.240 3.735 Air entrainment concrete slab 0.19 2.81 ≥0.4 500 0.285 4.215 Polystyrene froth plastic film 0.042 0.36 ≥0.1 20～30 0.055 0.468 Table 6 Zhengzhou area heat insulating layer should have smallest thickness Cement inflated pearlite board Air entrainment concrete slab Polystyrene froth plastic film Smallest thickness(mm) Thermal resistance (m2.k/w) Smallest thickness(mm) Thermal resistance(m2.k/w) Smallest thickness(mm) Thermal resistance (m2.k/w) 90 0.362 130 0.362 20 0.362 5 Conclusion (1) The steel bar

Ergonomic Analysis of Multi-Function Forest Fire Helmet Hongze Yang1,a, Bo Li1,b, Yanan Wu1,b and Bin Li1,b 1College of Mechanical and Electrical Engineering, Northeast Forestry University, Harbin 150040, China a9316762@qq.com, bid-workshop@sohu.com Keywords: fire helmet; ergonomics; safety; comfort.
However, as the reinforcing strip increase absolute height of the helmet, resulting in the overly high of center gravity of helmet, the stability of wearing is affected [5].
National standards require as follow: In the impact absorption performance test, the impact value in the head mode should be equal or less than 4900N; In the puncture-resistant properties, the steel cone and the head mode do not produce electrical contact; In the flame resistance ability, the continued burning time should be less than 5 seconds; In the side rigid test, the maximum deformation of helmet shell should not exceed 40mm and residual deformation should not exceed 15mm; In flame retardant performance test, the shawl fabric oxygen index should be equal or more than 30; In helmet shield performance test in using of 340 spectrophotometer, the visible light transmittance should be equal or more than 90%.
The important factor to influence the motion following stability is structural characteristics of suspension parts, especially mechanics of materials such as rigidity, damping, securing forces and so on.
The comfort of the helmet influences the firemen’s safety and forest property.

Moreover, the effects of body flexibility have been increasingly recognized as important factors in the dynamic loads and stability studies performed on the aerospace configurations.
The Reynolds decomposition defines flow property at this point as the sum of a steady mean component and a time varying fluctuating component with zero mean value, i.e. .
Using averaging and substitution in Eq. 1, RANS equations end up with the following forms (3) The viscosity,, is the property of the fluid and is the instantaneous strain rate tensor.
The Courant number (CFL) determines the internal time step and affects the solution speed and stability.
Journal of the Brazilian Society of Mechanical Science and Engineering, 26(2004) 290-296

Both temperature and frequency of loading significantly affect the values of G* and δ for asphalt binders.
Table 2 through Table 5 summarizes the properties of six asphalt types.
Table 6 presents the SBS properties.
Physical and mechanical properties of SBS Property Value Density(Kg/m3) 1302 Melting point (oC) 187 Color While Asphalt mixtures.
Anderson, The New Proposed Rheological Properties of Asphalt Binders: Why are They Required and How Do They Compare To The Conventional Properties, Physical Properties of Asphalt Binders, ASTM, STP 1241(1995)

The most important factor that affects the properties of an expansion joint is the width of girder-end gap.
“(Maximum apparent strain – residual apparent strain) / maximum apparent strain)” is defined as the ratio of recovery from deformation after unloading to use for assessing the deformation properties.
Table 2 reveals the following properties of the blocks: - The blocks are roughly divided into two groups according to their stress-strain relationships: G to I and J to L
Tabele 2 Results of the large deformation blocks loading test Deformation Properties of Blocks.
The first peak load of blocks J to L increased as the fiber content increased, but no marked differences were observed among post-peak load-displacement properties, showing dependence on the deformation properties of EPS.

It is widely applicable due to its unique electrical, optical, and mechanical properties.
From Fig. 5 (a) and (c), rGO shows higher electromagnetic wave absorbing potential and more obvious dielectric properties than GO.
Therefore, it is certain that it will not affect the absorbing performance of the absorbing material in the absorber as the substrate material.
Therefore, the main factor that determines the absorbing performance of rGO is the impedance matching rate.
References [1] Zhu Z, Sun X, Xue H, Guo H, Fan X, Pan X and He J 2014 Graphene–carbonyl iron cross-linked composites with excellent electromagnetic wave absorption properties J.

The experimental observations were interpreted using both phenomenological (Avrami) methods and micro-mechanical models.
Assuming axisymmetric deformation via octahedral slip [7], the average Taylor factors (MT) for the cast material compressed either parallel or transverse to the <100> fiber texture were 2.45 or ~3.1, respectively [8].
Other factors that affect the orientation dependence of recrystallization are briefly reviewed in the Discussion section below.
Nuclei for the starting structure then grow until impingement, transferring their orientations and Taylor factors to cells swept by the grain boundary.
A few variables are added to each MSU to quantify dislocation density, sub-boundary density/misorientation, or intrinsic properties such as its Taylor factor.

However, this approach has negative consequences such as the existence of insulating surface ligands and microscopic phase segregations which are limiting factors for the best performance of photovoltaic devices.
Ø Improve charge transport properties through metal nanoparticle doping.
Electronic properties of metal NPs depend largely on their sizes.
Table 4: Chemical and physical properties of commonly used solvents.
Properties of functional layers in inverted thin film organic solar cells.

Introduction Dislocations are frequently occurring lattice defects in materials, as a result of growth processes or of thermal and mechanical treatments [1,2].
In fact, as shown by Eq. (1), the average DCF is proportional to the mean square strain and, as such, it must respect the properties and related crystallographic invariance conditions of the elastic tensor.
Values of the Ei coefficients in Eq.(6) can be calculated if information on the dislocations (slip plane, Burgers vector) and on the elastic properties of the material (elastic tensors cij or sij) are known.
The Wilkens routine is the core of the calculation for the dislocation-related broadening, but is limited only to contrast factors parameterized as in eq. (7) and eqs. (5) and (5b).
Intensities are calculated on the basis of BaTiO3 structure assuming zero thermal factors.

We explore the flow patterns for each case, including the generated primary and secondary vortices, vorticity, velocity profiles, and fluid properties.
In parallel, under-relaxation factors (URFs) are applied to control the rate of variable updates, thereby stabilizing the iterative process.
As depicted in Table 4, the vortices’ locations and properties are quantified for Re1= Re2= Re3=1000.
Properties of primary and secondary vortices for one-sided lid-driven cavity, Re=1000.
Vortices locations and properties for three-sided lid-driven cavity with parallel upward motion, Re1= Re2= Re3=1000.