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Digital signature plays a more and more important role in e-commerce. The basic methods of digital signature are introduced and a digital signature scheme based on digital certificate is proposed in this paper. Digital certificate is generated after personal information is written. The effective data, RSA parameters and signature results are included in digital certificate. The related RSA parameters of private key certificate are encrypted by private key password. The digital digest is gotten through hash algorithm in this scheme. Digital signature is operated by using RSA parameters in private key certificate and the signature is verified by RSA parameters in public key certificate by verifier.

China has been the country which is suffering serious coastal erosion that primarily caused by the increase of hydrodynamic force and the unbalance between input and output sediment. Comparing with the traditional revetment, most of which were made of reinforced concrete, the ecological shoreline protection can prevent coastal erosion in an ecological method. In this article, a biodegradable coastline protection mat (BCP-mat) was proposed and different arrangement methods direct to various areas was presented to solve the problems such as high cost, complicated construction caused by existing ecological method. In the end, the existing technology problems and promotion difficulties was discussed in the perspective of design and management.

The terahertz (THz) spectrum technique has become an important research content of electromagnetic field in recent years. Folded waveguide backward wave oscillator (BWO) is suitable to be used as THz high-power electromagnetic radiation source. Because it can realize electronic tuning within a wide frequency band and doesn’t require pre-stage source amplifier. In this paper, the high frequency characteristic, the transmission characteristics, and the particle beam wave interaction characteristics of the structure of folded waveguide BWO have been analyzed, and it is utilized to design geometry parameters of 650GHz folded waveguide slow-wave-structure (SWS). The design is been validated by particle beam wave interaction simulation experiments. The experiment results show that the output is over 1.7W within 42GHz bandwidth, and the electron efficiency can exceed 1%.

PTT material is suitable for shaping clothing because of its excellent shaping and crease recovery performance, but if as underwear, the wearability of PTT material is being questioned. Based on the L9(34) orthogonal array design, two kinds of samples were kitted utilizing nylon core-spun yarn as ground yarn PTT/nylon filament and Polyester/nylon filament as face yarn respectively, mixed proportion and structure were controlled in the sample design. Test 6 basic wearabilities of samples, the wearabilities of samples were investigated by fuzzy mathematical analysis. The results of this research can be a good reference of shape wear fabric selection.

Empirical analytic method and theoretical analytic method are usually applied to calculate and predict water gushing yield in the tunnel engineering in the past but have much limitations and errors. Ample water source, hydrodynamic conditions and expedite channels are essential for water-bursting accidents in railroad tunnel engineering. From a lot of study of fractal geometry in rock mass, it is found that the multi-dimension value of fissure network is colligate reflection of the length, the direction, space and the number of fissures, so the value can be used to describe the complicated frameworks in rock mass. But it is a sound tackle to quantities the complicated frameworks. Numerical simulating method is convinced to be applied to calculate and predict water gushing yield of tunnel and underground engineering. It focuses on analyzing texture characteristics of water-containing medium, building hydro-geological conceptual model, and modeling long-term hydrodynamic field development. An experimental application in Paoziling tunnel under-crossing mountain reservoirs in Hunan province was presented in this article, and long-term hydrodynamic field development had been obtained under the condition of drainage from the tunnel, and the gush yield in the tunnel during the process of storing water in the reservoir was also predicted.

Recently, the tufted carpet pattern are getting more and more complex. However jacquard machine equipment is relatively backward and it has low degree of automation, which has caused a lot of labor and low efficiency. To solve these problems, the pattern forming principle of the tufting jacquard machine was studied and the design of automatic control system was put forward. So an embedded electronic jacquard machine controller based on ARM7 was developed.

New degradable cushioning packaging materials based on bagasse pith, magnesium bisulfite spent liquor and reinforcing silica were prepared by press-molding process. The effects of precipitated silica loading and the specific surface area (SBET) on the apparent density and the static compressive strength of cushioning packaging materials were investigated. Meanwhile, the microstructure and morphology of different types of silica fillers were analyzed by scanning electron microscopy(SEM). Static compressive strength of BPCPMs was improved significantly with the addition of 0.5%(w/w) silica. However, the compressive stress of BPCPMs increased at first and then decreased with increasing loading of silica. Increasing silica dosage increased cushion efficiency of BPCPMs at higher stress levels. The compressive stress increased with increasing SBET value, and under high strain conditions, the increase scale in compressive stress also improved.

The X-ray diffraction of hydrated calcium silicate is analyzed and is applied in papermaking. It shows that hydrated calcium silicate have certain crystalline state. The tensile strength, tearing strength and folding strength of paper decrease in different degree with the increase of dosage of hydrated calcium silicate while the whiteness and the printing color density of paper improve. T tensile strength and folding strength of paper decrease in varying degrees with the increase of dosage of PAM while the tearing strength of paper and the whiteness improve. And the printing color density of paper is the same.

Composite foam sandwich tube, which is a sandwich structure, improves stability of the tube and strength for use compared with single-layer composite, and is available in civil engineering as bearing member of light weight, high strength, and corrosion resistance. Axial compression experiment was made for fiber reinforced resin matrix composite foam sandwich tube which is laid in 5 different ways, and the comparing analysis on damage models was made according to experimental phenomenon. The laws of influence is preliminarily recognized by analyzing influence to foam sandwich tube of fiber laying, modulus of fiber, three dimensional elastic modulus ratio, tube radius, tube thickness.

This paper introduces the Changes in agricultural production of Hebei Province from 1949 to 2011,firstly.Then We analyzed the factors that influence the sustainable development of Agriculture.Finally, we put forward some development proposals.We hope to have reference to the other provinces of the sustainable development of agriculture .

This article puts forward the new research methodology during establishing evaluation index system of industrial manufacturing system competence in He Bei .Firstly, we establish a set of the primary evaluating Index system. Secondly,we assess and screen these Indexes. At lastly ,we determine the final evaluating Index system.The Index system is more objective in this way.

Based on the simulation of a eight-storey reinforced concrete(RC) frame, study has been carried out considering the rigid effect of infilled wall to explore the effect of masonry infilled on the framework by the difference of its quantity . MIDAS structural analysis software is used to make modal analysis and response spectrum analysis for the finite element models. In current chinese specification, infilled wall is often considered as nonstructual components in the buildings regardless load-supporting and shear-resistant action while the impact of rigid effect of infilled wall is not properly considered simply with the method of the reduction of structures’ vibration period. In this paper, a comparison to the current code was also made to get a better understanding of the difference between these two approaches.

Cationic polyacrylate emulsion was used as surface sizing agent and the effects of emulsion properties on paper mechanical properties were studied. The mechanical properties of sized paper gradually increased with the increase of solid content, viscosity and positive charge density of emulsion and decreased with the increase of particle size of emulsion. Tensile strength, folding endurance and tearing strength on machine direction were increased 33.62%, 11.99%, 6.79% respectively when the paper with single emulsion layer was used oven drying methods.

Cationic polyacrylate emulsion was used as surface sizing agent and the effects of emulsion properties on paper printability were studied. Cationic polyacrylate emulsion increases the printability of sized paper. The printability has greatly improved increase with the increase use of emulsion dosage, but the increase of emulsion viscosity influences the printing operation, and one layer of emulsion has already achieve the desired effect, therefore one layer of emulsion is properly.

The study object is wheat. Through the observation and analysis on the morphological structure of wheat plant, the concepts of microstate, substrate and microstate are put forward, the wheat growth mechanism model is established, and thus the description and control of wheat morphogenesis process could be realized. Based on the branch structure characteristics of plant, the wheat morphological data model based on axis structure is proposed to realize the structural storage of plant topological structure and organ morphological feature data. On this basis, based on the thought of "growth model - morphological feature model - geometric modeling - display model", the technical framework of wheat form visualization is established and on the VC++ platform, the virtual wheat growth system is built with OpenGL. The running result of the system shows that wheat morphological feature can be well simulated with the system to realize the virtual display of the growth process in the individual growth period of wheat.

In order to speed up the vehicles through the expressway toll station and reduce traffic congestion, we analysed of the No-waiting ETC(Electronic Toll Collection System) of expressway unifying the ETC theory and the RFID(Radio Frequency Identification Devices) technology. Firstly, we analysed system's hierarchy architecture, then detailed analysed the basic component of system, and designed the workflow and composing of functional modules, finally, established the model of ETC system of expressway based on RFID, it provides more practical guidance scheme for expressway ETC system.

This paper give a new design of three level phase delay control polarization controller, which is the key components for state of polarization (SOP) control in the area of coherent optical communication and polarization mode dispersion compensation. Piezoelectric ceramic are used in three of the phase delay unit to realize phase delay control. The polarization controller can achieve infinite control, convert arbitrary input state of polarization to arbitrary expected output state of polarization under low control voltage.

With the severe competition in the market, the risk that enterprises are faced with is more and more big. But so far, the development of the risk early-warning management system of enterprises in China is relative laggard. Based on this background, the theory of integrate risk early-warning system is studied and applied in Enterprise. The author hopes that it can offer some use to researching on enterprise integrated risk early-warning management.