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In wireless sensor network (WSN), LEACH protocol is a typical representative of the hierarchical topology control protocol. Compared to plane multiple hops routing protocol, it can significantly prolong the life cycle of the network. But LEACH protocol having the problem of uneven distribution at the cluster head election, this paper proposes a low energy adaptive clustering routing protocol based on the partition. On the basis of the partition, cluster heads are selected by the energy of nodes and their location information. Simulation experiments show that the proposed protocol can be more effective than LEACH to balance the energy and improve the life cycle of the network.

In wireless sensor networks, clustering class routing protocol is an important protocol type. Different clustering methods, and cluster head selection method directly affects the energy consumption of the entire network communication. This paper studies the effect of different partition methods of the network energy consumption, and to study the partitioning methods under the conditions of uneven distribution of nodes. We believe that energy efficiency clustering method should adapt the distributed of sensor nodes in order to improve energy efficiency. And according to the partition method we propose a low-power adaptive clustering routing protocol based on node distribution to partition. The protocol can effectively extend the lifetime of a wireless sensor network. Simulation results show that the proposed protocol can effectively prolong the network lifetime.

The inclusion complex of β-cyclodextrin (β-CD) and dibutyl phosphite (T304) was prepared by trituration. The tribological properties of the complex with different concentrations were investigated by a four-ball tester in the solution of polyethylene glycol-600 (PEG-600). The tribological test results showed that the complex exhibited better anti-friction and anti-wear properties than β-CD under different loads, and it was noted that the tribo-system showed the least friction coefficient when the concentration of the complex was 0.9%. It was proposed that the complex was decomposed into various molecular fragments and the T304 molecules were released under the friction condition. The XPS analytical results on the worn surfaces revealed that phosphide film formed by the released T304 played a major role and the iron alkoxide and carbon deposition films formed by the β-CD fragments had better anti-friction effect on the phosphide film surface. The interactions of different films resulted in the formation of a mixed boundary lubrication film.

Interlaced scanning has been widely used as a trade-off solution between picture quality and transmission bandwidth since the invention of television. During the past decades, various interlaced-to-progressive conversion algorithms have been proposed to improve subjective quality or coding efficiency. However, almost all the researchers concentrate on general cases, without making full use of specific application scenarios. Based on extensive investigations, eliminating visual artifacts in areas of subtitles and station captions for interlaced sports and news videos is still an unsolved problem, which will be addressed in this paper. Firstly, motion estimation is performed between field pictures. Secondly, text edge detection is proposed for sports and news videos. Finally, different processing strategies are applied to text regions and non-text regions. Experimental results show that the proposed method can generate much better text content than existing algorithms. In addition, it is quite stable for non-text parts.

In this paper, we study the Schur decomposition for unitary symmetric matrices: The formula for the Schur decomposition is obtained, and the relationship of the unitary symmetric matrix with mother matrix is also obtained.

In order to solve the problem of ECG being complex, and the problem of abnormal ECG signal analysis standards being not uniform, this paper analyzes Lin Zetao’s clustering algorithm research achievements in the classification of abnormal heart rate. According to the characteristics of the clustering algorithm which is suitable for dealing with the rare data and the large amounts of data, this paper makes the analysis of the method of setting parameters in key process of the application of the clustering algorithm. This paper proposes an accurate clustering algorithm (LCFCM) about abnormal ECG which combines logical judgment, cluster analysis and fuzzy clustering together. Based on the algorithm design requirements, this algorithm perfects the logical judgment criteria and the key technologies of the ECG waveform vector extraction method. Ultimately, the MIT-BIH database is used as the sample to make experiment. The experiment shows that, this paper proposes LCFCM algorithm, whose accurate rate toward the classification of the abnormal heart rate reaches 93%. And at the same time, the good self-adaptive algorithm on different individuals ECG, has good practical value.

Wearable electronic medical devices can realize non-intrusive and non-invasive monitoring of human body, which has the characters of removable operation, easy to use, long-lasting work, smart display diagnostic results, abnormal physiological condition alarms, wireless data transmission, achieve treatment data remote real-time monitoring and so on. In this paper, we collect information of the development process of wearable medical devices, and make the detailed description of the characteristics and development history about wearable electronic medical systems’ hardware and software design, pointing out the shortcomings and the development direction of existing equipment.

The measurement technology of 3D scanning in automation level is low, its measurement process is not stable, and the measurement error is large. After the principle of binocular structured light measurement was analyzed, match the marked point to multi-view registration based on the relative distance of any two marked point in space is unchanged. A multi-view registration is proposed using triangle constraint and global optimization. The method includes: remove the false matching points in possible matching points by joining triple constraint; after the first registration, use the center of marking points to global optimization through least squares principle method. The realization of the algorithm by use of tools such as VC++ and Open CV demonstrates that this method has the advantage of better restraining the accumulative error, keeping the process stable, and fast and realizing automatic registration.

The theoretical analysis of frost formation had been made. The wind speed, temperature and relative humidity etc. had different effects respectively. A single heating was studied through the experiment. In different outdoor conditions, experimental data showed evaporator frost at the environment temperature of 10 °C, environment relative humidity was 70%. Comparing the experimental data, it is concluded that temperature of evaporator’s outlet is increasing with the outlet temperature. The refrigerant evaporation temperature and COP under different conditions has been tested. The relation of evaporation pressure and environmental temperature under different evaporation temperature had been concluded. According to the experiment, a defrost measure of this experiment equipment had been proposed.

During the past years, Automatic control theory was founded. Especially in the foundation of engineering control theory, control science has formed a number of branches, such as population control, large system cybernetics, biological control and etc. Quality control of product in its whole life cycle is an important research object, especially driver development strategy in national innovation, quality and efficiency should be more collaborative developing. However, that several major engineering practice, the quality control of the situation is very serious, and urgent need to further study on the quality control theory.This paper puts focus on quality control and surveys the source of quality control, especially makes attentions to the development of theory method among quality control, control theory and engineering control theory, and then shows the developing map between quality control and control theory and finds that the quality control system caused by the fusion between quality control and control theory is one new method to break the bottleneck and suggests 4 block models of the quality control system.

This paper analyses the quality study based on the whole life cycle actions of the product by transformation of the Technology Readiness Level (TRL) and Project Progress by Fourier ,and designs the quality control system used by PID controller which simulated by Matlab software. Results show that the model is stable and accords with real situation, the outputs of quality control system and PID controller meet monotonically nondecreasing property and deviation convergents.

Marketing and Distribution Information Integration Platform (MDIIP) is the key point of informatization work for power companies. On this basis, the pater proposes a solution including overall architecture, function composition and system features etc. for Power Consumption Dispatching Management System (PCDMS) based on Transmission, Distribution and Marketing Data Integration Platform (TDMDIP). The system realizes the automatical combination of transmission, distribution and marketing model (TDM Model) and longitudinal interconnection of network topology, and effectively interacts real-time monitoring analysis features with daily operation management businesses. It not only expands the dispatcher’s view, but also improves intellectualization level of dispatching daily business.

A summary of Siemens T3000 system digital electro-hydraulic (DEH) self-startup control is proposed. On the foundation of analysis in turbine subgroup logic condition and step sequence, critical link and step sequence of turbine startup process is put forward, which is convenient for operator to master turbine startup characteristics quickly. Existing problems in DEH control logic are revealed and specific disposing measures are given. Application of the system in a 2×660 MW thermal power plant proves a secure and smooth operation of power units.

For armored vehicles electrical system fault diagnosis of fault original data collection difficult situation, this paper introduces the fault diagnosis technology based on fault tree model and fault diagnosis based on neural network technology, and the two kinds of fusion technology, complement each other, with a certain type of equipment control system as an example the case analysis, illustrates the fault tree of the neural network and the rationality and validity of the integrated fault diagnosis thinking.

As coal, oil, natural gas and other non-renewable energy consumption and increasing energy demand, the utilization of solar energy as a new energy is greatly enhanced. In this work, a grid connected photovoltaic solar air conditioning system is designed, mainly comprised of solar panel, controller, inverter, room air conditioner and other parts. Air conditioning systems rely mainly on solar photovoltaic power; achieve the effect of energy conservation and environmental protection. The experimental result indicates that the system can achieve stable operation and the utilization of solar energy driving air conditioning system to save electricity. This air conditioning system is compared with the ordinary air conditioning system, SEER can increase 10.6 ~ 29.4%, HSPF can increase 6.25 ~ 18.5%.

In order to obtain the low synchronous speed, fractional-slot concentrated-winding PM machine is adopted to wind power generation system. This paper analyzed the pole slot combination rule, and then studied the electromagnetic design method by taking 12-slot and 10-pole machine. By using the finite element software, the characteristics is analyzed for this fractional-slot concentrated-winding permanent magnet generator, the research results show that this generator has good performance, thus prove that fractional-slot concentrated-winding scheme is feasible and effective.

Make old cement concrete as recycled aggregate can not only protect environment, saving resources, but also can reduce the project cost, and promoting the sustainable development. This paper based on the related recycled concrete aggregate (RCA Recycled Concrete Aggregate) literature, mainly involve its properties, preparation and performance of RCA concrete, construction application etc..This has got a lot of reliable conclusions, so as to give some inspiration and help to the related scholars.

The size distribution of carrying capacity as the forefront of current non-equilibrium transportation of non-uniform suspended sediment research was introduced. The nonequilibrium transportation of suspended sediment concept was further studied. The preliminary calculations and verification of the size distributions of carrying capacity and effective bed material under nonequilibrium transportation condition were given after derived by Qiwei Han. The formula is tested by experimental data and the theoretical results are consistent with the measured values.

Human sitting posture and dynamic behavior at work are analyzed systematically by using the principle and method of ergonomics. And from the scales and functionality limited by both aspects, put forward new design ideas of office chair which are fit to modern office work so as to provide reference to design practice.

A new approach to the generation of an initial point is proposed for discrete combined shape, which improves fully the local searching capability of discrete combined shape algorithm. Combined shape algorithm is embedded into genetic algorithm as a combined shape operator. Consequently a hybrid genetic algorithm for structural optimization with discrete variables is proposed. The constrained optimization problems were dealt with by adaptive annealing penalty factors and penalty function. The numerical results show that improved combined shape genetic algorithm for structural optimization with discrete variable problems has a faster convergence speed, which has advantages of local searching capability and globally searching capability of genetic algorithm. Improved combined shape genetic algorithm is an efficient optimal design method for engineering structure.

Composite concrete filled steel tubular (CFST) column is a new type of column having high ductility and high load-bearing capacity. In this paper, the finite element analysis software ABAQUS is used to study the seismic performance of 3D joint of composite CFST column and steel beam. The hysteretic curve and skeleton curve are obtained by changing the strength grade of the steel beam; calculate the energy dissipation ratio of the joint. The results show that the higher the beam’s steel strength the higher ultimate capacity of the joint in the constant axial load. But the full degree of hysteresis curve, energy dissipation and displacement ductility of the space joint decrease.

When a skew bridge is analyzed, it is difficult to treat skew boundary conditions with general space beam element in single beam calculation of skew beam bridge. The stiffness of skew bridge cannot be simulated efficiently. In order to improve the accuracy of skew bridge, the stiffness matrix of the space skew beam element is derived based on the principle of minimum potential in this paper, this element is suitable for single beam of skew bridge and grillage method. A corresponding program is completed by Visual C++, the calculated results of different finite element models are compared, so the validity of the proposed model in this paper is validated. This paper can provide reference for plane and space calculation of the skew bridge design.

The paper designs the urban-rural power grid dispatching fault diagnosis expert system which acquires fault information by SCADA system of automatic system of urban-rural power grid, and uses artificial intellegence method to analyze fault information and make fault diagnosis. The paper implements the core part of the fault expert systemthe design of knowledge base and fault inference engine.

In this paper, in order to understand fully the development of failure mechanism, bearing capacity and seismic performance of the steel H-beams and composite concrete filled steel tubular (CFST) column joints strengthened by outside strengthening ring, in the space zone the effects of changing the axial compression ratio is investigated. A 3D joint finite element model is built up by finite element software ABAQUS, the elastic-plastic finite element analysis is carried through numerical modeling process. The analysis results showed that low axial compression ratio has a little influence on the bearing capacity; with the increase of axial pressure the bearing capacity will decrease in a high axial compression ratio, moreover the failure pattern of joint changes from beam end to column end. The ductility of the specimens is decreased by raising axial compression ratio.

The wastewater originating from fifteen different constructive sites in Yunnan is selected as research subjects, and then detecting the possible pollution index in the wastewater. It turns out to be that unattainment rate of SS is as high as 93.5%; the average contents of COD and BOD5 are 632.52mg/L and 255.39mg/L, both of which are over the emission standards to 66.7%; production wastewater is weakly alkaline; other index is beyond the approved discharged standards slightly. The main pollution factors of urban constructive sites wastewater are SS, COD, BOD5 and pH. The secondary pollution factors are petroleum, TN, TP and animal and vegetables Oil.

In this paper, the finite element analysis software ABAQUS is used to study the seismic performance of the joints of rectangular steel tubular columns filled with steel-reinforced concrete and H-shaped steel beam in different beam strengths, which are under the same axial compression ratio of 0.2. By the finite element simulation, we can get the load-displacement curves and skeleton curves from the end of H-shaped steel beam. According to the curves and dates, the seismic performance of the joints is analyzed. The shape of each restoring force curves presents for full square spindle, reflecting that the beam-column structure can effectively absorb the seismic energy; with the enhancement of H-shaped steel beam’s strength, the ultimate bearing capacity of the structure is gradually increasing, however, the stiffness and overall stability of the components become worse by degrees; the change of ductility property about the joints is not obvious, showing good seismic performance.

This article researches seismic performance of the joint of cellular steel column and steel beam through simulation of the finite element software. With the change of axial force, we can attain the load-displacement hysteretic curves, skeleton curves under the different axial compression ratio, and then analyze their bearing capacity, ductility, energy dissipation and other mechanical properties. Results show that, the decrease of axial compression ratio is helpful to improve the bearing capacity of specimens. The joints of cellular steel column and steel beam have full hysteretic curve, good ductility and seismic performance.

One-dimensional consolidation equation of unsaturated soils was derived in order to solve this special case of consolidation. The presented equation, not similar to Terzaghi’s equation, is a type of absolute nonlinear partial differential equation, and it was solved by finite difference method. An example was analyzed and the case of incompressible fluid consolidation was compared. Finally the experimental results from laboratory tests reported in the literature, was fitted by the presented equation, and the agreement was good. The results show that (1) the process of pore-air pressure dissipation is similar to that of pore-water pressure of saturated soils; (2) the compressibility of pore fluid is not an advantageous factor to quicken the consolidation; (3) the presented equation is effective to analyze the process of consolidation of unsaturated soils which consolidate mainly due to the dissipation of pore-air pressure.

The article researches seismic performance of joints of cellular steel column and steel beam by finite element simulation. Finite element model is established by using the finite element software reasonably. Considering about the hole position and the distance of center of hole as invariant moments, under low cyclic loading we can attain hysteretic curves and skeleton curves etc. which are compared and analyzed in different opening rate by simulated software. The results show that for a certain axial compression ratio (n=0.45) of joints of cellular steel column and beam, the reasonable opening rate can improve the seismic behavior of the joints.

In this paper, the finite element analysis software ABAQUS is used to study the seismic performance of the joint of crisscross concrete-filled steel tube core column-steel beam tested by the pseudo static simulation under low cyclic loading. Then we can get the load-displacement curves of the joint when the axial compressive ratios are 0.2~0.9. By the data analysis can be drawn: the joint of crisscross concrete-filled steel tube core column and steel beam has good ductility and strong plastic deformation capacity, and it can absorb the seismic energy largely; within range of smaller axial compression ratios, the ultimate bearing capacity of the joint has increased with the increasing of axial compression force, however, in range of larger axial compression ratios, the ultimate bearing capacity of the joint has reduced with increasing of the axial compression force; and ductility of the beam-column joint has no obvious decline when the axial force increases.

The paper designs the urban-rural power grid dispatching fault diagnosis expert system which acquires fault information by SCADA system of automatic system of urban-rural power grid, and uses artificial intellegence method to analyze fault information and make fault diagnosis. The paper implements the core part of the fault expert system—the design of knowledge base and fault inference engine.

With the rapid development of network bandwidth, the matching-performance of regular expression is gradually of crucial importance for networking security. There are many hardware acceleration designs of regular expression matching on the basis of NFA and DFA, of which NFA designs require more logic circuit resources while the DFA designs more memory resources. However, because there are too many states and transition edges in DFA, the performance of DFA is much inferior to the performance of NFA. In this paper we designed a DFA regular expression matching algorithm fully based on FPGA logic circuit. The algorithm exploits the feature of DFA that many transitions for a state may have the same next state pointer and setting a default transition for each state of DFA will result in the reduction of logic circuit and the simplification of the electronic circuit. To evaluate performance, this DFA algorithm was mapped onto the Altera Cyclone FPGA, and got the experimental results based on the L7-filter rule set. The performance of the DFA algorithm acquired an approximate performance compared to the NFA algorithm. Experimental result shows that, compared with the NFA algorithm, in the improved DFA plan, 10% rules got a higher throughput, reaching 60% in the best case; while 62% rules cost less logic resources, saving 87% logic resources in the best case.

Aiming the problem of the armored vehicle's gun control system that there are many kinds of internal devices, complex fault reasons ,but no all-around and online fault diagnosis and state inspection mean, The automatic test platform for the gyroscope group with performance test and fault diagnosis for component and circuit is designed .The platform based on dependency matrix and optimal criterion of the maximum failure feature information entropy optimize test points ,choose optimal test points design. Performance test module is created and provides test result information for fault dictionary in fault diagnosis module. Automatic test platform is able to locate the circuit component failure.The platform is tested by actual vehicle experiment, and the results prove the reliability and validity of the platform.

The fault diagnosis of vehicle power system that the structure and characteristics of components are complex, each module and internal modules exist coupling, cross-linked mutual relations and the uncertainties, the system status and working conditions are difficult to describe by precisely mathematical model, and test cost expensive, less fault samples. Thus its fault diagnosis is the decision problem of uncertain information in a small sample. it is proposed that combining multi-signal flow graph model with Bayesian network fault diagnosis method. The fault diagnosis model of power system and the corresponding Bayesian network structure are built, which achieve the fault diagnosis of power system, Diagnosis example shows that the method of the vehicle power has a higher failure troubleshooting capabilities of the system single and multiple faults.

Wear-resistant polyurethane (PU)-based materials were prepared through addition of chemically modified aramid and PE fibers. The morphologies of PU-based materials were examined. We observed that treated fibers can be added to 10%, resulting in useful materials with very stable properties. Besides, bending strength of the materials increased from the 10 ~ 15 to 55 MPa, which greatly broadens the range of its applications. In this research, we also examined volume wear, heat resistance, and surface grinding marks morphology and observed very good performances.

Graphene nanoplatelets (GNP) and nylon (PA) have been often used as thermal filler and matrix and respectively to produce composites. In this work, PA6/PA66/GNP thermal composites were prepared via a melt blending method. Mechanical properties, morphology, and thermal properties of PA6/PA66/GNP composites were investigated. Because the GNP is very expensive, we investigated to use Al2O3 and graphite and examined the characteristics of the prepared composites. Thermal conductivity values of PA6/PA66/GNP composites remarkably increased with increase of GNP contents mainly via layered dispersion in nylon matrix. The thermal conductivity of composite containing 50 wt % of GNP was measured as 5.03 W·m–1·K–1 at 30 °C, indicating an increase of more than 15 times compared with that of the neat PA6. When the Al2O3 was replaced for GNP, the thermal conductivity of composites decreased, but the mechanical properties improved. When graphite was used to replace for GNP, thermal conductivity basically remained unchanged but mechanical properties decreased.

The wastewater originating from small vehicles washing which comes from 30 car washing stations in Kuming is selected as research subjects and tested. The results turn to be as follows: the pollutant indexes of the car washing wastewater are chromaticity, SS, COD and LAS, which beyond the approved discharged standards of A, B, and C in varying degrees. There are differences in the same parameter values from diverse car washing stations, such as SS is up to 923 mg/L. Pollution levels of pollutants’ indexes are various and their differences are in those descending orders: Chromaticity>LAS>SS>COD. Therefore, when establishing treatment facilities, pollution levels should be specially taken into consideration. Moreover, car washing station need to consolidate managing measures and standardize the drains.

As for the two main limitations as partial constringency and convergence hysteresis of Genetic Algorithms (GA), predatory search is introduced and Predatory Search Genetic Algorithms (PSGA) based on GA is designed to enhance the integrate ability of hunting. The concepts of fire support platform and target fitness are introduced, and fire power distribution model based on fire support fitness coefficient is built. The improved PSGA is applied to fire power and emulation experiment is done. The result of emulation shows the validity of the improved algorithm.

This paper studies the solution to combat aircrafts path planning problem in confrontational battle space. First of all, according to the dynamic movement characteristics of emergent threats, a path planning target function model is built based on dynamic threat; then based on the defects of basic genetic algorithm, a kind of improved genetic algorithm based on predatory search strategies is further designed; finally the model and the algorithm are tested effective by simulation verification.

Mobile e-commerce systems are the big trend of international economy and social development now days, and also the key process of industry upgrade, industrialization and modernization in our country. Mobile e-commerce systems are considered as the backbone of the manufacturing industry in China, Vulnerabilities in web applications continue to be the most frequently discovered security problem. This article illustrates a trusted operating systems how to provide a flexible solution to the problem of application for e-commerce. With the help of Chinese Wall, web services are becoming popular in Web applications. In the end, we present strategies for e-commerce application: trusted e-commerce module.

It is very significant for hydrological telemetry system to gather such real-time information as rainfall and water level of reservoir in order to improve forecasting level of flood prevention and flood disaster. In this paper, a novel hydrological telemetry system is presented. The system mainly consists of remote terminal units (RTUs) and monitoring center. The RTU is mainly designed to collect rainfall and water level, and send this information to the host computer in the monitoring center by GPRS network or other wireless network. The RTU is completely implemented on a low power consumption hardware platform. The host computer receives the data from the RTUs and analyzes them, then gives detailed tables, diagrams and some decision-making conclusions, which helps the competent authorities of the reservoir or the dam to realize remote monitoring and alarming system. The design principles, difficulties and skills are discussed detailedly in the paper. The low power consumption of the RTU and bit error rate for GPRS communication are both tested. A prototype is developed to validate above design cruces.

Vertical prestressing tendons finishing twisted steel is widely used in the concrete box girder, but ,it is hard to effectively control the loss of anchor stress. Based on the dynamic, the three-parameter model was built which include the frequency of the exposed segmentthe segment length of the exposed steel reinforcements and effective tensile force. The vertical tensioning force of the box girder webs model was designed at laboratory .The natural frequency was obtained through test. Relying on experimental test data ,the model of the nonlinear relationship between fine bundle the rebar tensile force and the exposed segment frequency was established. Here in NDT methods to be able to quickly and effectively measured vertical prestressing tension.

A kind of differential method is proposed for to eliminate noise disturbance and signal delay problems in ship heading control. First, an asymptotic observer is designed without ship motion dynamic parameters. Then, it proves that the observer is stable and the convergence conditions if given. At last, simulation result shows that the designed observer can suppress noise in ship heeding signals, and differential delay is improved.

Based on basic principle of detection using impact-echo method, in combination with urgent demand of grouting quality inspection in ducts inside post tensioning type prefabricated box girder in bridge engineering, impact-echo method has been used for non-destructive detection of grouting compactness in pre-stressed ducts inside prefabricated box girder. Verification by beating away measuring points shows that the impact-echo method can accurately locate metal corrugated pipes and qualitatively judge grouting compactness inside prefabricated box girder ducts, to allow effective inspection of grouting quality in strands of pre-stressed ducts.

To the distribution status of agricultural products, this paper proposes a multiple-type vehicles refrigerated distribution route optimization model with soft time windows, innovatively considering that different type vehicles have different marginal and travel costs, and applies genetic algorithm to solve it. Finally, this paper uses an example to check the model, and proves that the model is feasible and effective.

This paper uses the large-scale finite element analysis software ABAQUS to simulate 12 cross steel reinforced concrete special-shaped columns with the control variables of axial compression ratio and rate of steel bone, and subjected to the monotonic load with 20mm horizontal displacement. 6 columns work under the different axial compression ratio of 0.0, 0.4, 0.5, 0.6, 0.7 and 0.8. Other 6 columns are made of different rates of steel bone with different steel bone thickness of 0mm, 2mm, 4mm and 6mm, 8mm and 10mm, and subject to vertical axial force in axial compression ratio of 0.3. By simulating, we obtain the load - displacement curve of different axial compression ratios and different rates of steel bone, and analyze the effect of the bearing capacity of the cross steel reinforced concrete special-shaped columns in different parameters. The results show that the bearing capacities of the columns decrease with the increasing ratio of axial compression, and increase with the increasing rate of steel bone.

The development and utilization of clean and renewable marine energy sources will be a way for the development of economy. Although on a global scale the advantages of renewable energy are not in doubt, the impacts on the local environment must be carefully considered. The sonar devices could be used to monitor the underwater environment around the marine renewable energy device. In this paper, a Multi-beam Echo Sounder is introduced. And the measured results in a lake are given, which are shown that this sonar could detection the fish effectively.

This paper studies the construction problems of five order nonnegative matrices from spectrum data. Let be a list of complex numbers with . Necessary and sufficient conditions for the existence of an entry-wise nonnegative 5×5 matrix with spectrum are presented.

In this paper, three types of urban sewage treatment cost model, Oxidation ditch, ICEAS and A2/O are established respectively. The cost model and the analytic hierarchy process (AHP) were applied to sewage treatment plant for process optimization. It provides guidance for urban sewage treatment process decision-making.

Attention is put on FDTD algorithm to simulate electromagnetic travelling underground with XFDTD software in this paper to get echo data of underground plant rhizome. A reasonable simulation model is established with some permittivity and conductivity, and choice of grid size and absorbing boundary is supposed to simulate detecting ability for plant rhizome. Adding noise model is supported and wavelet threshold de-noising algorithm is used to process echo signal with noise, and root mean square error (RMSE) is obtained with different SNR. At the same SNR, the relationship of target echo and object size is presented.