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Portable breath acetone sensor has great potential in diabetes diagnosis for acetone is a selective breath maker for diabetes. In this paper, we propose a multilayer semiconductor sensor for acetone gas sensing. Device is designed with stress adjustment layer, support layer, metal layer, insulator and sensing film. Simulation is performed, electrothermal and thermomechanical analyses demonstrate that this device has good performance in power consumption and thermomechanical reliability.

As the backbone of the national science and technology development, intellectual property management of scientific research project has become one of the most important links in the intellectual property’s protection and management in China. With the policy deconstruction and reconstruction method, the critical steps of the intellectual property management have been isolated from the policy documents and combined back together to build the whole process system of intellectual property management in scientific research project. Three elements of a system, participators, process and productions, have been identified and reasonably reconstructed to build the system.

The automatic monitoring system for coal mining subsidence is introduced from the main research contents, composition of system, construction of system, etc. in this paper. The system is based on GNSS CORS technology, GIS technology, computer network communication technology, mobile PDA technology, modern measurement data processing technology. It takes GNSS reference station subsystem, GNSS CORS monitoring station subsystem, data monitoring center subsystem, subsystem of real-time data acquisition terminal and subsystem of communication as core modules. Equipment monitoring, data collecting and transmitting, data processing and analyzing ,subsidence predicting and early warning, mining damage evaluating are built up into a automatic monitoring system for coal mining subsidence. This system can provide decision-making basis for mine safety mining and geological environmental governance.

Frequent pattern mining has been an important research direction in association rules. This paper use a methodology by preprocessing the original dataset using fuzzy clustering which can mapped quantitative datasets into linguistic datasets. Then we propose a algorithm based on fuzzy frequent pattern tree for extracting fuzzy frequent itemset from mapped linguistic datasets. Experimental results show that our algorithm is shorter than the F-Apriori on computing time to huge database. For large database, the algorithm presented in this paper is proved to have a good prospect.

The cost of public rental housing depending on the view of life-cycle has been studied. The construction project life-cycle cost management paradigm consider both of the cost in construction period and the cost in operation period was proposed. The proposed construction of projects cost includes not only the cost of funding sense, should also include environmental costs and social cost. By reducing life-cycle cost of public rental housing, maximize the project value, so the economy and people's livelihood can truly improved.

Traditionally compliant mechanism is difficult to achieve decoupling features, because of lack of definite theory and its deformability character. Whereas its counterpart - many rigid mechanisms with decoupling property have been designed and the method of mechanism design with decoupling feature is constructed. In this paper, an effective method to build equivalent transformation between rigid decoupling mechanism and compliant mechanism with decoupling property is proposed, and also applied to design new a decoupling rigid mechanism with 3-DOF. Finally, the decoupling features of the micro motion platform was verified through FEM analysis software ANSYS because of difficulty of compliant mechanism analysis.

The velocity distribution coupled thermal and fluid flow a rib-tube was studied in this article. Based on theory analysis and numerical simulation, we choose modal and wall function to simulate the flow in rib-tube, velocity to definite the dispersed phase. The governing equations were built and solved by numerical way. The progress of flow and heat exchange in rib-tube, the rules and contours of temperature, velocity were obtained, they shows that, along the rib-tube, velocity was changed with the temperature rising , which could give us a reference for engineering application .

This paper uses the world universal finite element software ABAQUS to establish a finite element numerical calculation model of the structure of lattice type steel sheet pile. for the same condition of different soil depth of design elements of lattice type steel sheet pile wharf structure, calculation and analysis of the calculation results and research get the relevant conclusions for reference.

The flow of liquefied natural gas (LNG) which was coupled between heat transfer and fluid-flow in rib-tube was studied in this paper. Based on theoretical analysis, the model and wall-function were chosen to simulate the flow field of rib-tube, and the multiphase flow was described by the mixture model, in which the dispersed phase was defined by different velocity. In addtion, self-defining functions were used and governing equations were set up to solve the dispersed phase, and the result were compared with the experiment. The process of fluid-flow and heat exchange on rib-tube was simulated, and the contours of temperature, pressure, velocity, gas fraction were obtained, which showed that, the parameters of above changed when the temperature was rising and the LNG evaporating along the rib-tube, and a mixed process existed in the middle of the heat tube.

This paper studied the management and monitoring graduation-designing platform of the university undergraduate based on the internet technology. Practice has proved that the platform can let the students write graduation-designing journal of the electronic version at any place at any time; It can update their completion status of the graduation designing in real time; Teachers in the colleges and universities can land the platform and gave the answers to the students questions in time with a variety of ways. It truly achieved the new 4W comprehensively monitoring and management pattern that some "cage-free" serious professional students of the graduation designing, especially represented by the IT professional students.

It was hard to obtain sensitivity distribution of Inlet electrostatic sensor by mathematical model and analytic method. To this problem, the sensing model and sensitivity function of circular electrostatic sensor were established by Point-charge principle. In addition, the main factors to electrostatic sensor sensitivity were analyzed and discussed by ANSYS with an optimized probe size. Accordingly, this simulation analysis had provided a theoretical basis and guidance for latter designs of inlet electrostatic sensor as well as guidance for structures of experimental environment of aero-engine gas path.

The mixed materials come from Beijing Daxing District, corn stalks as the main raw material, peanut shells and wheat straw as affixation. Combustion characteristics of mixed materials are studied by using Thermogravimetric analyzer and combustion dynamics studied by using Coats-Refern method to offer practical and theoretical data for crop straw combustion and Densified . Studies have shown that Combustion curve of three samples have two distinct peaks, divided into water evaporated to dryness, and the combustion of volatiles, fixed carbon combustion and burnout four basic stages and lied a larger overlapping area in the entire combustion stage, That combustion characteristics and kinetic parameters of mixed materials are influenced by adding peanut shells, and less affected on adding wheat straws.

The study investigated the amount of mulching plastic film residue in corn¡¢potato and vegetable fields in Inner Mongolia Autonomous Region. The result shows that there has been a very serious pollution, and the average amount of residue of mulching plastic film remained in the farmland of Inner Mongolia is 36.3kg/hm2. The average amount of residue of mulching plastic film remained in the corn field soils is 56.25 kg/hm2, the potato fields were38.7kg/hm2, the vegetable fields were 25.05kg/hm2. The results also showed that more than 73% residual film remains in the 0 ~ 10cm plow layer, and the amount of plastic film residue depends on duration of utilization of mulching plastic film, and the longer the duration of utilization, the more plastic film residue is left in the field.

Lattice type steel sheet pile wharf is a new type of wharf structure, which is increasingly and widely used, but its structure is complicated, and the calculation theory is not perfect. This paper uses the general finite element software ABAQUS to establish the finite element numerical calculation model of grid shape steel sheet pile structure. The result was deeply researched and analysed,so some useful conclusions are drawn that can be used as references in the engineering application.

The principle of gas path electrostatic circular sensor was discussed in this paper, in addition, a monitoring experiment with self-made circular sensor was carried out on turbojet engine, and electrostatic signals were collected successfully to verify the validity and feasibility of the sensor. According to the signals monitored over 131h, typical signals of 233-240 phases were analyzed. It was proved that the unusual particles were caused by carbon deposition from fuel spray nozzle. Therefore, under real-time monitoring of gas path changes with electrostatic circular sensor, early warning could be provided for initial fault condition as well as real-time reference for condition-based maintenance.

The paper introduces a method of fault diagnosis using fuzzy set theory. In the paper, the principle that a fault symptom either exists or doesnt exist is abandoned. A crisp number between 0 and 1 is used to denote the degree of fault symptom, by which the fault symptom vector is constructed. For every kind of fault symptom, a fuzzy pair-wise comparison matrix is constructed. The elements of the pair-wise comparison matrix are triangular fuzzy numbers which denote the qualitative comparisons between the membership values of the given fault symptom with the reference to a pair of possible faults respectively. The least logarithm squares method is applied to determine the membership of the fault symptom with respect to each fault, and then the fuzzy diagnosis matrix is constructed. A simple weighted addition is used to calculate the fault vector based on the fuzzy diagnosis matrix and the fault symptom vector. Center of area is used to determine the best non-fuzzy performance value of the fuzzy number, according to which the fuzzy numbers can be ranked. The ordering of all the possible faults based on the fault symptoms is determined. At the end of the paper, an example is used to demonstrate the procedure of fuzzy fault diagnosis.

The clamber animal foot pads were researched by the Super Depth of Field3D Microscopic System marked VHX-600 and the flexible non-smooth surface friction mechanism of clamber animal foot pad was analysed through bionic tribology. The total friction includes two aspects: a) The sliding friction caused by the adsorbability between clamber animal foot pad and external surface. b) The embedding resistance caused by the external surface micro particles embedded into clamber animal foot pad. The mathematical model of single convex hull was built and the different center distance bionic surfaces were designed, the friction contact simulation of bionic surface was done by ANSYS and the friction performance of bionic surface was verified through the plane friction testbed.

With the development of Condition-Based Maintenance, there is an urgent need for failure dependence of redundant components in parallel system. In this paper, Markov maintenance cost decision analysis based on failure dependence of components was put forward, moreover, maintenance cost optimal model of parallel system with cost rate was established, meanwhile, the minimum cost rate as well as corresponding optimal detection interval was obtained. Finally, failure dependence and dependent failure rate to parallel system maintenance cost optimal model were studied and realized to prove this theory.

The start and speed control problems of motor were analyzed in port machinery, the advantages of frequency conversion and fluid viscous start were synthesized, the speeder based on frequency conversion and fluid viscous soft start was designed. The start of motor can be protected by fluid viscous soft start, especially in the stationary start under the load. The motor can be realized infinite speed control by frequency conversion device, the use safety of motor is protected and the work efficiency is enhanced, then the aim of energy saving is realized.

In this paper, a low Reynolds number airfoil (S1223) is the objective of the study. The Navier-Stokes equations were established to simulate the complex flow around a low Reynolds number airfoil, in which the turbulence model was used. The complex flow around the airfoil was simulated at 2x105 Reynolds number and its aerodynamic characteristics were analyzed. The relationship among lift coefficient, drag coefficient and angle of attack was studied.

In this paper, solar photovoltaic system utilized in building sectors in China is assessed. For photovoltaic, the main reason causes low utilized is high capital cost. Another problem for photovoltaic is that solar cell has low efficiency when utilized in practical. In this study, some works have done to assess PV utilized in building sectors in China from the technology and economic aspects.

The blind have so many inconveniences in their lives. In recent years, more and more blind sidewalks are designed and built for them. This is good news for the blind. However, people would consciously or unconsciously leave some stuff on the blind sidewalk. Therefore, the occupation of blind sidewalk is a serious problem gradually. We decided to develop an application on smartphone to help the blind to avoid troubles referred above. Within the camera on the smartphone, the application detects obstacles on the blind sidewalk based on image processing and warns the blind that there are obstacles in front of him. This paper proposed an approach on detecting the direction of blind sidewalk after the blind leave the blind sidewalk to avoid the obstacles. We used several algorithms of image processing and conduct several experiments to exam this system.

In this paper, solar thermal technologies utilized in building sectors in China is assessed. For solar thermal technologies, the main reason causes low utilized is high capital cost. In this study, some works have done to assess solar thermal technologies utilized in building sectors in China from the technology and economic aspects.

As a kind of UNB modulation method, time-phase modulation has a specialty that its power spectrum is concentrated around the carrier frequency. Thus, it can work within a narrow channel interval without interfering the conventional communication system. In this paper, the performance of multiple users was analyzed for time-phase modulation based on the correlation coefficient. It can be found that wider carrier frequency difference between adjacent users is necessary for time-phase modulation due to the modulated information consisted in the very wide sideband. Moreover, the influence between multi-users will fluctuate versus the difference of carrier frequency, which diminishes as a whole when the difference of carrier frequency increases.

This paper briefly analyzes the structure and conservation approaches of building energy consumption, analyzes the forming reason and influence factors of heating and air-conditioning energy consumption and proposes the passive energy conservation designing strategies of low energy consumption building. Through the passive methods of building design, envelop enclosure and planning landscape, the goal of last year building low energy conservation can be achieved.

The filling earth pressure calculation inside the Sunken Large Diameter Cylindrical Structure is very complex. This paper used large-scale finite element software ABAQUS to establish numerical model, and validated it by the experimental data, then analyze the main cause of earth pressure change inside the cylinder.

Geothermal resource is a very clean source of energy, and its exploration and development has a history of almost one hundred years. In this paper, the mathematical model of multi-physical field on the platform of Comsol Multiphysics software was set up about the flow-solid-Thermal numerical model. During the analysis, rock porosity and permeability of stratum were taken into consideration to study change state of the temperature of export wells and injection wells. Besides, porosity-temperature curve fitting and permeability-temperature curve fitting were made respectively to study the relationship between the stratum temperature and permeability and porosity.

Recently silicon components have been applied in mechanical watch movements. Among them, the silicon hairspring is the most attractive due to the significant improvement of accuracy and performance compared with the traditional material. However, the current device in production is unable to measure the spring constant which determines the timekeeping accuracy of the watch. This paper presents a method to measure the spring constant of silicon components. The setup is based on Variocouple with a force sensor. The data processing is realized by Matlab. The result shows that the spring constant is calculated rapidly and accurately.

In order to solve the complex thrust allocation problems of dynamic positioning ship with azimuth thrusters, thrust allocation and management system was built. The power optimal thrust allocation was formulated as a quadratic programming problem by the linear treatments of inequality constraints and the optimal solution could be found in a finite amount of time. And some influence factors of thrust allocation were separated from algorithms and treated as a superstratum management module. Using this system, online adjustment of input constraints and singularity avoidance can be realized, and the reliability and adaptability of thrust allocation are improved consequently. Finally, the validity and excellent performance of this method is proved by the simulations.

In order to study the whole system performance of dynamic positioning ship, a simulation platform which contains environment and ship model, as well as basic guidance, navigation and control functions is established. Besides the ordinary ship and environment modeling, a guidance method for waypoint following is designed by using path interpolation and circle of acceptance. A sensor-fusion based federated filter is proposed to deal with the problem of state estimation and wave filtering. To make the whole system becomes a closed loop feedback system, a PID method are applied to deal with the control problem. By using this simulation platform, this paper simulates and studies the basic functions of a typical dynamic positioning ship. Finally, the simulation proves the validity and excellent performance of this dynamic position ship simulation platform.

Power Law Model and Cross Model are widely used in Metal Powder Injection Molding computer simulation analysis. The feedstock viscosity data of Ti-6Al-4V is got through field tests, regression analysis is used to calculate the model parameters, which provides the theoretical basis for the application of computer simulation analysis in metal powder injection molding.

There are many constrained optimization problems in engineering. Bio-inspired optimization algorithms have been widely used to solve various engineering problems. This paper presents a novel optimization algorithm called Lifecycle-based Swarm Optimization, inspired by biology life cycle. LSO algorithm imitates biologic life cycle process through six optimization operators: chemotactic, assimilation, transposition, crossover, selection and mutation. In addition, the spatial distribution of initialization population meets clumped distribution. Experiments were conducted on a Vehicle Routing Problem with Time Windows for demonstration the effectiveness and stability. The results demonstrate remarkable performance of the LSO algorithm on chosen case when compared to two successful optimization techniques.

There are two common research methods on the dynamic states model of belt conveyor in China at present. The mathematical model is built by finite element method then it is solved by numerical method. And the continuous model is built when the belt is treated as elastic body then it is solved by mathematical method. This paper puts forward the establishment of continuous model, the model is solved by FDM and the simulation results are given.

Using coordinate measuring machine(CMM) PMM12106 to measure the standard template, various factors will affect the accuracy of its calibration results. Based on system analysis of the various factors in the calibration process, application of test data, the paper proposed a new calibration method considering the key factors, like measuring rod deflection, probe diameter, and temperature and so on, evaluated the uncertainty in measurement, then programs. Compared to NIM data, it concludes that the measurement data is accurate, reliable, and suitable for the calibration of the standard template whatever it is API standard template or Premium-thread standard template.

Aiming at the shortcoming of commonly used assessment methods, this paper introduces SVM to information system security assurance capability assessment, builds a corresponding assess model. The simulation result shows that the method can get high assessment accuracy, and can solve the problem of subjective bias brought by experts and the problems of easily trapped into minimum point and over-fitting of neural network, the method is suitable for information system security assurance capability assessment.

The bottleneck assignment (BA) and the generalized assignment (GA) problems and their exact solutions are explored in this paper. Firstly, a determinant elimination (DE) method is proposed based on the discussion of the time and space complexity of the enumeration method for both BA and GA problems. The optimization algorithm to the pre-assignment problem is then discussed and the adjusting and transformation to the cost matrix is adopted to reduce the computational complexity of the DE method. Finally, a synthesis method for both BA and GA problems is presented. The numerical experiments are carried out and the results indicate that the proposed method is feasible and of high efficiency.

This article introduces briefly the design feature of thread gauges used in the inspection of API round thread casing and coupling thread standoff, and expounds some questions relating to the extending amount, the positive and negative sign of standoff P and P1, the thread number of hand tight standoff A and the revising of short round thread standoff, which may be ignored easily in the control and inspection of the casing and coupling standoff. The article also gives the right inspecting procedure of the round thread casing and coupling thread to avoid erroneous judgement in the course of standoff inspection.

Apply the rapid prototyping in the 3D reconstruction of solid model of lumbar. By separating the original CT image data according to threshold value, filling and repairing the hole and generated the STL file of lumbar, using Geomagic and UG NX software to complete the model of intervertebral disc and assembly of lumbar. Finally, the model was manufactured through FDM Vantage i rapid prototyping machine.

In this paper we evaluated some surface characteristics of the Vacuum Aluminized Paper (VAP) to explore the ink adhesion on it. It is shown that this performance is quite unsatisfying due to the high gloss of the VAP which results in an even weaker surface energy than the surface tension of ink. The optimal drying time for the inked VAP under UV light with 125W of power is approximately 4.5 minutes, converts to the practical production, the printing speed of the VAP should be near to 7128 sheet/hour so as to fully solidify the UV ink thus acquires the optimal adhesion of ink.

The problematic of this research paper is that why design aesthetics has nothing to do with design practice? Aim to this problematic, this paper take a primary review on contemporary aesthetics and by review on Barthes’s semiotics, then, we propose the discourse of design culture code as a supplement of design aesthetics, for answer the problematic of this research.

The removal efficiency of dibutyl phthalate (DBP) and its environmental hormone treated by biofilm reactor has been investigated. Besides, the the kinetic model of the degradation of DBP and its degradation products in the reactor have been discussed. The results indicate that the biofilm reactor had a positive effect on the removal of DBP and was able to significantly reduce the environmental hormone in DBP influent. The activity of β-galactosidase dropped from 13.55 millers to 3.3 millers and the removal efficiency of DBP reached 98.5% at water temperature 20°C and HRT (Hydraulic Retention Time) of 4 hours. The metabolic intermediate of DBP in the reactor mainly consisted of dibutyl phthalate and phthalic acid. The kinetic models of the degradation of DBP can be expressed by Lawrence-McCarty equation.

Continuous cooling transformation (CCT) diagram of steel 22MnB5 was studied using dilatometer method. The influence of the hot forming process parameters, such as the heating temperature and holding time on the mechanical properties and microstructure of stamped parts was analyzed by tensile tests and the metallographic observation on the parts with various processing parameters. The microstructural evolution obtained from the dilatometer samples reveals that the cooling rates not smaller than 20K/s induced fully martensitic microstructure. As the cooling rate decreasing, more ferrite and pearlite or more bainitic microstructure forms. Tensile tests results show an excellent tensile strength and ductility combination of 22MnB5. The tensile strength and yield strength reach 1500MPa and 1200MPa respectively, with total elongation of around 10%.

A new structure of mechanical pulse CVT –rotational swash plate pulse CVT was put forward. This paper analyzed the impact of helical gear parameters on swash plate pulse CVT characteristics, it can be seen that the angular velocity of output shaft is proportional to the angle between Swash plate surface and vertical cross section of the input shaft and the swash plate surface, the gear modulus has no effect on the transmission ratio, the guide rod pitch diameter is the major factor contacting gear tooth Strength, when the other parameters unchanged, ( is the pitch helix angle)is proportional to the output torque, and is inversely proportional to the output torque.

Fault-block oil and Gas Field is one of special complicated reservoirs. For its development, No matter at home or aboard, the instances are not too many, and most of them are terrestrial oil reservoir. For ocean fault-block oil reservoirs, there are no instances that can be consulted. This paper aims at some ocean fault block oil reservoir .Gray relation model and fuzzy cluster analysis are combined to set gray fuzzy cluster analysis .Through a case analysis ,gray fuzzy cluster method is used to clustering of reservoirs. with the experiences that has been obtained, so that the foundation are provided for the development of some ocean fault block oil reservoir.

Based on uncertainty theory, this paper proposes a method that constructs and analyzes fault tree. In this paper, it would be characterized as crisp number if fault rate of bottom event is obtained from reliable handbook, empirical data and so on; it would be characterized as uncertain variable if fault rate of bottom event has no statistical data but is obtained from expert's subjective judgment. The optimistic value of overall system’s top event is calculated by using uncertain simulation technology. Finally feasibility and validity of this method is confirmed by taking fault tree of internal combustion engine as example.

In this paper, cutting experiment and FEM simulation are combined to investigate the effect of various chamfered edge geometries on cutting force and cutting temperature distribution when hardened steel GCr15(HRC60+2) is machined with PCBN tool. The research results indicate that radial force and main cutting force increase with the enlargement of chamfer angle, and especially, radial force rises more significantly, but radial force is less than main cutting force during the entire cutting process. Cutting temperature also gradually rises as chamfer angle increases, and moreover, it is maximized on the chip-tool interface in a place of 0.1-0.2mm distant from nose.