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Early detection of ovarian cancer is challenging, leading to high mortality rates. Paclitaxel has broad-spectrum anti-tumor activity and has been used clinically for the treatment of various cancers. However, the severe side effects of paclitaxel limit its use at high doses. Hence, it is imperative to develop a novel anti-neoplastic agent that can enhance therapeutic efficacy and selectively target tumor sites, thereby mitigating systemic toxicity. In this study, lipid nanoparticles with surface-modified octreotide were constructed by a thin film dispersion method to co-encapsulate paclitaxel and neferine, which are lipophilic compounds, within the phospholipid bilayer, improving their solubility. Liposomes modified with octreotide can increase its active targeting to SKOV3 cells through SSTR-mediated endocytosis and prolong the drug circulation time in vivo. The potential synergistic effects of paclitaxel and neferine were confirmed and quantified by Synergyfinder analysis software. In vitro experimental results showed that neferine can synergistically enhance the cytotoxicity of paclitaxel against human ovarian cancer cells, exerting anti-proliferative, apoptosis-inducing, invasion-suppressing, and angiogenesis-disrupting effects. The in vivo targeting and tumor inhibition of Octreotide-modified liposomes that co-deliver paclitaxel and neferine (OCT-PTX/Nef-Lips) were investigated in mice xenografted with SKOV3 cells. In vivo pharmacodynamic evaluation demonstrated the safe and effective ability of OCT-PTX/Nef-Lips to inhibit tumor volume growth, disrupt tumor tissue morphology, induce apoptosis in tumor cells, and suppress their proliferation. Furthermore, angiogenesis was inhibited through down-regulation of angiogenesis-related proteins (TIE-2, VEGFA, VE-Cadherin, Ang-2).

Solid catalyst plays the governing role in the heterogeneous Fenton-like catalysis for water purification. In this work, the Co(II)-doped C3N4(Co/C3N4) was prepared and further thermally exfoliated in different atmosphere for the three-dimensional layered configuration. The morphological and structural properties as well as surface chemistry of Co/C3N4before and after thermal exfoliation were elucidated in comparison. The oxygen-exfoliated Co/C3N4(O-Co/C3N4) exhibited accessible metal exposure and synergistic pollutant adsorption stemmed from three-dimensional layered configuration with ordered porous configuration, oriented lamellar structure and increased surface area. Moreover, an excellent Fenton-like reactivity and stability was measured for PMS activation and pollutant degradation, and the comparative performance before and after oxygen exfoliation as well as with typical metal-based catalysts were investigated in details. The impacts of testing conditions and water matrices were elucidated to estimate environmental potential. Based on radical identifying and inhibiting tests and electrochemical measurements, the non-radical reaction pathway from mediated electron transfer (MET) played the key role with much reduced matrix effects and satisfactory catalytic selectivity. This work provides a new chance to save transition-metal consumption and refine Fenton-like reactivity in C3N4-based catalysts for superior environmental remediation.

A novel principle of cup wheel grinding of rotating concave quadric surface was proposed. The mathematical model of machining process was established to prove the feasibility of precision grinding of rotating concave paraboloid based on the introduced principle. The conditions of non-interference grinding of concave paraboloid were mathematically derived. The processing range and its influence factors were discussed. The trajectory equation of abrasive particle was concluded. Finally, the math expressions of numerical controlled parameters was put forward in the process of grinding of the concave paraboloid.

High hardness surface coating sphere components are widely used in metal sealing ball valves. The spherical surface grinding texture influences the valve’s tribological performances such as friction, lubrication and wear of interacting surfaces. It can be used to develop the index of grinding parameter optimization. In this paper, based on the discussion of sphere generating grinding methods, the surface grinding texture is quantitatively analyzed. The space trajectory of abrasive particles during sphere grinding is studied. The trajectory mathematical models are built based on two kinds of sphere grinding manners and are verified by comparing the theoretical results against experimental measurements. The influence of grinding parameters on the texture is analyzed. Texture density are defined to quantitatively describe the surface texture. The relationship between grinding texture and ball valve performance is finally discussed. The conclusions can help to optimize the spherical surface grinding process.

In this paper, the birch flour was the raw material with its particle size less than 100μm and the polyester hot-melt adhesive was used as binder with its particle size less than 60μm. The birch flour was dried using high speed mixer with heating function. The birch flour/polyester composite were prepared using the physical mixing method. The surface of the specimen and fracture surface of specimen were analyzed through the micrographs of scanning electron microscopy. In order to study the characteristics of laser sintering, the preheating temperature of the powder bed of laser sintering machine and the processing parameters of the birch flour/polyester composite were determined using single layer sintering method and empirical method. The tensile, flexural and impact specimens were built in the two scanning laser ways of subarea scan and progressive scan. The testing results show that the mechanical properties using subarea scan method are superior to those of progressive scan method and the mechanical properties of the specimens increase as the laser scan speed decreases. The best mechanical properties of SLS specimens of brich flour/polyester composite powder were obtained with the following parameters: the laser power was 11W, layer scan speed was 1800mm/s; layer thickness was 0.1mm; laser scan spacing was 0.1mm and the average tensile, flexural and impact strength of specimens were 1.35MPa, 3.69Mpa and 0.73KJ/m2 respectively.

Bamboo flour is a kind of a cheap reproducible natural plant powder. The polyamide hot melt adhesive (polyamide) is good bamboo adhesives. The bamboo flour/polyamide blend is prepared through mechanical mixing method. The powder bed preheating temperature of the laser sintering processing and the processing parameters of bamboo flour/polyamide blend are determined through the differential scanning calorimetry method (DSC method) and single layer sintering experiment. The mechanical testing parts are successfully fabricated by selective laser sintering using the bamboo flour/polyamide blend of 25/75 (wt/wt). In this series of experiments, the average tensile strength, flexural strength and impact strength of 5.9Mpa、11.5Mpa and 4.5KJ/m2 are obtained when the laser power is 11W, scan spacing is 0.1mm, the thickness of a layer is 0.1mm and scanning speed is 2000mm/s. The tensile strength and flexural strength of the SLS specimens are improved through wax infiltrating process, while the average impact strength of the wax-infiltrated specimens decreases compared with the SLS specimens processed under the same set of parameters. Bamboo flour/polyamide composite powder is new laser sintering with good forming property and low cost.

Based on the background of Dalian subway running through bridge pile foundation, a 3d numerical model is built by the finite element software MIDAS/GTS in order to research the laws of the internal force and the displacement of the pile and soil during the Construction process. The outcome reflects that the sedimentation value of the top of the pile is bigger than others. Because the bigger thrust about the shield machine, the horizontal displacement of the pile is increasing at first and decreasing at last from a positive into a negative. Because of the loss of the soil, the soil beside the pile collapses and causes strong friction force. The surface sedimentation value which is near the central line of the tunnel is bigger than other place. This paper is of good reference roles in the similar underground engineering in Dalian.

The aim of this study is to examine the roles of entrepreneurial orientation (EO) and the guanxinetwork with parent university (GNPU) in the creation of university spin-offs (USOs). The study replicates and extends previous research on academic entrepreneurship by providing an empirical analysis using data from 140 USOs in China. The empirical results indicate that three dimensions of EO (innovativeness: IN; proactiveness: PR; and risk-taking: RT) and GNPU have positive effects on the financial performance (FP); PR, RT, and GNPU have positive effects on non-financial performance (NFP) of USOs. In the context of moderating effects, this study finds that only GNPU positively moderates the relationships between IN and FP as well as between PR and NFP, failing to find others. Generally speaking, EO is an important strategic asset and GNPU is an important organisational resource that underpin the establishment of USOs. In addition, we also provide some important theoretical and practical implications for scholars, practitioners, and policy-makers.

Based on the problem of tunnel running through bridge pile foundation, a 3d numerical model is built by the finite element software MIDAS/GTS in order to research the internal force and the displacement of the pile and soil during the Construction process. The sedimentation value of the top of the pile is bigger than others. Because the bigger thrust about the Shield machine, the horizontal displacement of the pile is increasing at first and decreasing at last from a positive into a negative. Because of the loss of the soil, the soil beside the pile collapses and causes strong friction force. The surface sedimentation value which is near the central line of the tunnel is bigger than other place. This paper is of good reference roles in the similar underground engineering in Dalian.

In order to study the kinematic characteristics of the tree transplanter and the hydraulic cylinder, this paper established the model of the tree transplanter with the Cero2.0 software and analyzed kinematic characteristics of the hydraulic cylinder and the tree spade when the tree spade was driven by the hydraulic cylinder with the analytical method. The dynamic simulation curves of the angular velocity and the angular acceleration of the hydraulic cylinder can be obtained with the Matlab software. Then the appropriate format model file was imported into Adams software, and the angular velocity and the angular acceleration of the hydraulic cylinder were analyzed and simulated in Adams. The obtained curves in Adams software were compared with the curves obtained with the Matlab using the analytical method. The result revealed that the trends of the two ways simulation curves were consistent. The comparison showed the analytical method of kinematic characteristics of the tree transplanter and hydraulic cylinder was correct.

Using mechanism design and dynamic analysis software, the simulation is conducted about grasping operation and moving objects for multi redundant manipulator on the basis of mechanism design and theoretical research, as well as the snake crawling motion simulation. The simulation results validate the correctness of theory analysis. The each joint driving torque data and curve provided the effective data basis for the design and development of a prototype.

This paper discusses the pole placement with low-order controllers, e.g., PID type controllers and phase lead/lag compensators, using parameter space approach. The damping ratio sector region and the relative stability region in s-plane, which form a trapezoid region in the left-half of s-plane, are mapped into the controller parameters space. Thus, the corresponding controller parameters can place all the closed-loop poles in a specified trapezoid region, and guarantee the performances of the closed-loop systems. The advantage of the proposed method is that it is simple and can be applied to time-delay systems. A simulation example is given to illustrate the effectiveness of the design.

The paper took a structure improvement of a coupling component for board-level photoelectric interconnection and analyzed its coupling efficiency by stimulation. Firstly, it briefly introduced the commonly used coupling components, analyzed the coupling performance, and selected a coupling component to improve its structure. Secondly, it introduced methods to improve coupling components, such as 45-degree gold-plated cross section, and manufacturing ball lens on both the top and the bottom to increase the coupling efficiency of coupling components. Finally, the optical simulation software Advanced Systems Analysis Program was applied to analyze the coupling efficiency. The coupling efficiency of improved coupling component was increased. The analyses and results are significant in engineering application and guiding.

The acoustic performance of sound-isolating and decoupled tiles is studied from macroscopic and microscopic. First, the sound absorption and reverse sound insulation performance of sound-isolating and decoupled tiles is studied based on laminated media; then the acoustic decoupling materials influence on acoustic radiation of double cylindrical shell underwater is studied, using a double-layer cylindrical structure of large-scale as experimental model .There are large amount of operating modes designed in this experiment, such as all laying, partial laying, laying and so on. The results show that sound-isolating and decoupled tiles not only have the effect of weakening the absorption of reflections, but also have reverse sound insulation effect, which increases as frequency increases; for single point mechanical vibration, the tiles can effectively inhibit vibration and sound radiation of high frequency in the double shell.

A new type of foam fractionation column with spiral internal had been designed for enhancing the foam drainage and thus for the removal of minute hazardous materials. Chromium was separated from wastewater using the continuous foam separation method. According to the similar physical behavior of foam separation and chemical reaction processes, the equivalent chemical reaction constant was introduced, Establishment concentrate distributed mathematical model of the whole tower under the condition of continuous foam separation with SDS as active agent. The model has been tested by experiments. The result indicated that foam separation process could be regarded as a first order reaction, and diffusion coefficient was 4.86cm2/s.

Subjected to external pressure, buckling analysis is key problem in the roof shell design of large scale cylinder gasholder. Two simplified buckling analysis methods, the continuous orthotropic plate method and the split-rigidity method, are introduced to check the general instability of stiffened spherical shallow shell. Considering the plate and the stiffeners in two directions with the same contribution to the bending stiffness, the equivalent bending thickness formula is put forward. The finite element model for a 100,000 m³cylinder gasholder roof is setup. The buckling critical loads obtained prove that the split-rigidity analysis method and formulae are applicable. The results can be referred in design of stiffened spherical shallow shell.

This paper discusses the parameters tuning of fractional-order controller satisfying the desired gain-margin and phase-margin specifications in terms of a stability equation method applicable to fractional-delay systems. The tuning procedure is then applied to the level control of double water tank, which is modeled as a second-order transfer function with time-delay. The Matlab simulations and the experiments on the water tank device show the effectiveness of the tuning and the benefits of using fractional-order controllers.

It is necessary and valuable to build the transferring relationship between test bed datum and ship datum for satisfying the boundary requirements of exciting forces in ship’s vibration-acoustic analysis. Principle of the force transferring technique for machineries with multiple supporting points is introduced first, and then the measurement method for free velocities of machineries is given. A method for transferring test bed datum to ship datum of machinery force characteristics is discussed and applied to deal with a practical problem, in which the numerical simulation is used for predicting admittance of ship mounting seat absenting reality. Experimental results show that the proposed method is valid.

Finite cylindrical shells with stiffened ribs are major structure of cabin on the submerged or underwater vehicles. This paper aims to probe into the feasibility of sound radiation simulation of underwater structure based on ABAQUS. ABAQUS is used to compute and analysis the underwater sound radiation rule of double cylindrical shell structure. And the computation data agrees with the experimental data basically. Adopting boundary impedance technique and acoustics IEM technique to simulation infinite flow field is feasible, and adopting acoustics IEM technique has much better performance. Boundary impedance technique is promoted for the concerning of accuracy. The results indicate that ABAQUS is appropriate to solve underwater sound radiation problem and it can satisfy the requirement of project application, which provides a new analysis method.

With the SMA (Shape Memory Alloy) banner model, the effect of pre-stressing and displacement, stiffness and length to the energy dissipation ratio is studied. The two equations, which are of pre-stressing and displacement to the energy dissipation ratio are proposed. The method are put forward to confirm the stiffness and length of SMA . Based on the above analysis, a new pull-press SMA damper is designed. The simulation analysis on seismic response of five-floor frame with SMA damper shows that the displacement and acceleration of the top floor are reduced by 50﹪at least. It verifies that this kind of SMA damper can availably suppress the seismic response of structure.

In this paper, the influence of the tool rake angle, cutting depth and cutting speed on exit edge defect sizes are discussed by the two dimension cutting experiment of SiCp/Al composites. The sizes are measured by using the Keyence VHX-1000C type super preview 3D microscopy. The results indicate that exit edge defect sizes are influenced greatly by tool rake angle and cutting depth, and are influenced slightly by the cutting speed. The edge defect sizes have an overall downward trend when the tool rake angle is smaller than 5°, and have an apparent upward trend when the tool rake angle (γ0) is 10°.The length (L), height (H) of exit edge defects and the negative shear angle increase with increasing of the cutting depth.

Hydrogenation of alkali lignin was carried out in the presence of Pd/C catalyst at hydrogen pressure 1∼5 MPa. Catalytic activity of Pd/C catalyst was investigated according to the structure changes of alkali lignin, which were characterized by UV and 1H-NMR spectroscopy. The measurement of average molecular weight undertook by gel permeation chromatography (GPC). Changes on function groups of alkali lignin were analyzed through chemical methods. Results show that total hydroxyl, phenolic hydroxyl and alcoholic hydroxyl increase 64.23%, 37.10% and 89.67%, respectively, while carbonyl and carboxyl decrease separately 43.50% and 53.41%. No significant differences of the total acidic groups and the phenyl structure were found after reaction. GPC analysis shows the weight average molecular weight (Mw) and number average molecular weight (Mn) are both decreased, and the polydispersity of alkali lignin is increased The active function groups of alkali lignin are increased obviously, and reactive activity of alkali lignin is enhanced as a result. The present results demonstrate Pd/C catalyst shows an excellent catalytic activity on reductive reaction of alkali lignin and hydrogen.

The feed drive system model of NC precision sphere grinding machine (MD6040) is constructed. Although a large number of researchers pay more attention on advanced controllers, most high performance machine tools still adopt PID (Proportion Integration Differentiation) controller today. In this paper, PDF (Pseudo-Derivative Feedback) controller and PDFF (Pseudo-Derivative Control with feedforward Gain) controller which evolved from PID controller are studied. The performance of PID controller, PDF controller and PDFF controller is investigated by simulation and experiment. Both simulation results and experiment results showed that PID controller has severe overshoot and less rise time, PDF controller has strong robustness and long rise time and PDFF controller possesses the advantages of the other two controllers. PDFF controller is more suitable for NC precision sphere grinding machine feed drive system.

Cr(III)-containing wastewater was treated by continuous foam separation process. The factors affecting the Cr(III) removal efficiency were researched. The optimal operating conditions determined by orthogonal experiments are as follows:wastewater pH 6.50,gas flow 400ml/min,cationic surfactant dosage 50mg/L.When the mass concentration of Cr(III) in the influent is 7.5mg/L,the effluent can meet the national discharge standard with 98% of Cr(III) removal rate for continuous running. The kinetic experimental results show that the foam separation of Cr(III) accords with the first order kinetic equation. The results of continuous experiments in a scale-up foam separation column indicate which reach the Second Wastewater Discharge Standard of Country.

It is much valuable to find a method for predicting the middle and high acoustic characteristics of big and complex structures such as ships and airplanes. Impact of the ring frequency and the damping on the vibration transmission is discussed firstly. Then the feasibility of the model simplification method for big and complex structures whose acoustic characteristics will be predicted is analyzed. At last, the simplification method was applied to predict the middle and high frequency sound radiation of the double complex cylindrical structures. Numerical results showed that the proposed method has the same accuracy as the conventional finite element method and boundary element method, and can be applied to deal with engineering problems.

One novel highly cross-linked, shape-controllable molecularly imprinted sol-gel film (MISF) with good thermal and chemical stability and three-dimensional network porous structure has been developed. The binding characteristic of the imprinted film to bifenthrin was evaluated by equilibrium binding experiments and imprinting-induced promotion of binding. The MISF was modified into the wells of 96 micro-well plate combined with chemiluminescence (CL) technology to establish the molecular imprinting-chemiluminescence (MI-CL) sensor. The high throughput and high selective detection sensor of bifenthrin was applied in vegetable and food samples with satisfactory results.

Cement concrete has an increasing utilization in highway construction. However, the lower flexural tensile strength and abrasion-resistance restricted the development of concrete pavement with heavy traffic. Hence, It has highlighted the need for research on high performance concrete (HPC). The design of specific concrete normally depends on the mixing of mineral admixtures in concrete mixture. This paper presents the first experimental study on strength and abrasion-resistance enhancement admixture (SAEA) mixed with slag powder, steel slag powder and silica fume. The optimal proportion of three mineral admixture and reasonable mixed amount of SAEA were then given, and the mechanism of SAEA reacted in concrete was analyzed based on sol-gel theory. Lastly, the effect of concrete mixed with SAEA was validated and the micro-structure transformation of specimens was given by SEM.

By determining membership function of the input parameters and selecting defuzzification method, the evaluation model which can be used to intelligent analyzing the causes of SMT solder joint defects was set up. The fuzzy neural network was trained by using the output variables of the training samples from intelligent discrimination as the input variables of training samples of fuzzy neural network. The fuzzy neural network was tested by using the output variables of the testing samples from intelligent discrimination as the input variables of testing samples of fuzzy neural network. The results show that by using the evaluation model the cause of SMT solder joint defects can be analyzed intelligently and the results of intelligently analysis are reasonable, the evaluation model can be used practically.

Laser rapid forming is a kind of new developed technology combining laser surface modification and rapid prototyping technology. It provides a powerful tool for the manufacturing and repairing of metal components. Laser rapid forming repairing experiments of 45 and 2Cr12 steel have been carried out with 316L stainless steel powder. Microstructure and properties of the repaired components are analyzed and tested with optical microscopy (OM), scanning electron microscopy (SEM) and electronic tensile experimental machine etc. Repaired components of different materials have been metallurgically bonded with the deposited layers, with fine microstructure, better mechanical properties and free of defects.

This paper presented a new technique, which was the online wear evaluation of wheel in grinding WC-Co coating by using wavelet packet decomposition. Based on the measurement method, theory of online wear evaluation of wheel was introduced. The selection principle of characteristic signals was brought up, and the grinding acceleration signal was the best choice among many characteristic signals. The time domain signal analysis method of wavelet packet decomposition was analyzed. Lastly, experiments on the wear of wheel were performed, and experimental results showed the validity of the method.

This article deals with the problem of determination of the stabilizing parameter sets of Proportional‐Integral‐Derivative (PID) controllers for first‐order and second‐order integral processes with time‐delay. First, the admissible stabilizing range of proportional‐gain is determined analytically in terms of a version of the Hermite–Biehler Theorem applicable to quasi‐polynomials. Then, based on a graphical stability condition developed in parameter space, the complete stabilizing regions in an integral‐derivative plane are drawn and identified graphically, not calculated mathematically, by sweeping over the admissible range of proportional‐gain. An actual algorithm for finding the stabilizing parameter sets of PID controllers is also proposed. Simulations show that the stabilizing regions in integral‐derivative space are either triangles or quadrilaterals. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society

Multi-walled carbon nanotubes (MWNTs)-Fe3Al was prepared by spark plasma sintering. Microstructural investigations show that MWNT remains in the composites. The magnetic properties were investigated with alternating gradient force magnetometer, which shows that the composites still display good soft magnetic property. The MWNTs-Fe3Al composites have a similar magnetic hysteresis loops to that of Fe3Al, indicating the good soft magnetic properties of the composite. Excellent magnetic property implies that MWNT-Fe3Al composites may also have significant potential for applications in electronic-magnetic nanodevice fields.

The surface texture of sheet steel plays an important role for automotive applications. To achieve appropriate surface topographies and press-forming behaviour, a new laser coating texturing (LCT) technique aimed at texturing steel work-rolls was proposed. The laser texturing process was realized by applying laser pulses at very high repetition rates to produce innumerable micro-craters with the required shape profile on the surface of the rolls. Moreover, the surface alloying of the dimples was carried out on the substrates of bearing steel GCr15. The submicron WC-Co alloy metal powder was melted into the micro-craters by high laser energy. The effects of processing parameters on the properties of the laser textured samples were investigated. The dimpled surfaces were examined by a 3-dimensional surface profilometer. Microstructures of the coating layers were assessed by optical and scanning electron microscopy. The experimental investigations show that the laser-dimpled hard-coated surfaces exhibit compatible metallurgical interfaces with the substrates. The laser coating textured roll is demonstrated to have excellent abrasion resistance and a much longer service life. The abrasive wear resistance was 5 times higher than that of the substrates. The average surface microhardness values were as high as 700HV.

The processing parameters of laser texturing are linked with the wear property of roller surface based on the relationship between the fractal parameters and surface roughness. The influence of laser power density, scanning speed and pulse width on the roughness is analyzed though experiments. The effect of fractal parameters on the wear rate of the roller is analyzed with fractal geometry model for wear prediction. Condition of achieving engineering surface with optimal fractal dimension is presented and the expression of the optimal fractal dimension is derived. It shows that the roughness of laser textured surface and normalized wear rate are mainly determined by laser power density and fractal dimension, respectively. Moreover, to get the textured surface with smallest nominal wear rate, processing parameters of laser texturing, especially the laser power density, should be controlled properly besides the material properties of the roller. The result will provide guidance for the processing.

To investigate the effect of micro-topography on the wear properties of the cold roller, rough surface was characterized with fractal geometry, and the profile of laser-textured surface was measured based on the analysis of surface profile self-similarity, feasibility of fractal characterization of the surface was studied with power law method. Results show that Isotropic surfaces tend to be fractal and surfaces processed under definite technological conditions can be characterized with fractal geometry. On this basis, effects of surface fractal parameters on the wear rate of the roller were analyzed with fractal geometry model for wear prediction. Condition of achieving optimal fractal dimension was presented and the expression of the optimal fractal dimension was derived for the minimum normalized wear rate. It shows that normalized wear rate is mainly determined by fractal dimension besides the material properties and an optimal fractal dimension existed for the engineering surface is affected by the plastic index, normalized true contact area and scale coefficient. The results will provide bases for the studies of friction and lubrication of the textured steel sheet and guidance for the actual processing.

This paper deals with an on-line mismachining error measurement for curve grinding based on digital image processing. Using CCD camera, the contour of the workpiece’s finished surface is captured and the image is preprocessed for denoising and edge detecting. The worktable is guided by the image of the finished workpiece to follow the path of the finished contour and then the real curve of the finished workpiece is measured by fitting a curve according to the moving path of the worktable. Finally, the machining error is obtained by comparing the measured curve with the theoretical curve of the workpiece. This method is applied to a CNC curve grinding machine MD9040. A measurement experiment is given. The experiment results show that the measurement method offers high detection precision and can be used in wide fields, especially for measuring the parts with complex curve.

This paper deals with an application to automatic compensation of grinding wheel wear by an image processing based real-time measurement method in dry curve grinding. An online image measurement system was schemed out and its principle was introduced in detail. Real time image of workpiece and grinding wheel is grabbed by CCD camera during grinding process. For the purpose of increasing the measurement precision, a new sub-pixel level accuracy edge detection approach combining Zernike moments operator with Sobel operator is proposed for locating the edge of the machined workpiece, which has advantages of fast processing speed and high edge locating accuracy. The wear amount of the grinding wheel is calculated by the image processing software, and is compensated automatically by NC controller. Finally, this method is applied to a new type CNC curve grinding machine MD9040. The experimental results show that the measurement and compensation method proposed in this paper is effective, and the contour error of the workpiece with real-time compensation is less than the feeding resolution for a compensation of 2μm.

Spindle thermal deformation is the main error source of many precision profile grinders. In this paper, the relationship between spindle temperature and either radial or axial thermal deformation is studied based on experiments. The placement and amount of temperature sensors are optimized. Then a kind of thermal error modeling method based on support vector machine is presented and applied in the modeling of thermal error of profile grinding. The result shows the model is robust and the on-line accurate prediction of grinding thermal error is realized based on monitoring of temperature rise of spindle. Finally, the error compensation strategy is discussed for further application of thermal error modeling.

This paper presented a new technology, which was the online wheel wear evaluation in grinding WC-Co ceramic coating by using wavelet packet decomposition. On the basis of the measurement methods, theory of online wear evaluation of wheel was introduced. And the selection principle of characteristic signals was brought forward, the grinding acceleration signal was the best choice among many characteristic signals. The time domain signal analysis method of wavelet packet decomposition was analyzed. Lastly, experiments on the wear of wheel were performed, and the experimental results showed the validity of the method.

A novel truing and dressing method, namely dry electrical discharge (dry-ECD) assisted truing and dressing, is proposed to overcome the shortcomings associated with conventional mechanical dressing methods, ELID and ECD methods. The macro/micro complex feed mechanism in dry –ECD assisted truing and dressing equipment is designed to maintain continuous discharge between the tool electrode and diamond wheel in dry-ECD automatically. A series of basic performance experiments of the micro feed mechanism show that the position accuracy of the micro-feed mechanism is below 0.35μm using the micro-positioning control system. Whereas，the position accuracy of the mobile negative electrode is 1μm without macro/micro complex feed mechanism.

The bending problem of a functionally graded anisotropic cantilever beam subjected to thermal and uniformly distributed load is investigated, with material parameters being arbitrary functions of the thickness coordinate. The heat conduction problem is treated as a 1D problem through the thickness. Based on the elementary formulations for plane stress problem, the stress function is assumed to be in the form of polynomial of the longitudinal coordinate variable, from which the stresses can be derived. The stress function is then determined completely with the compatibility equation and boundary conditions. A practical example is presented to show the application of the method.

This note focuses on a graphical approach to determine the stability region, in the parameter space, of PID-controlled second-order plants with dead time. This work is the extension of and further results on the same topic of the previous paper in the literature on first-order plants with dead time. The main characterization of the new method is the utilization of a graphical stability criterion in the parameter space, which releases a necessary and sufficient stability condition. Once the range of proportional gain is known, the complete stabilizing set in the plain of integral-derivative gains can be drawn and identified immediately, not to be computed mathematically. A practical algorithm of drawing the stabilizing boundaries in the integral-derivative space is proposed. [ABSTRACT FROM AUTHOR]

Image analysis was used to evaluate the curve grinding process. The measurement system organization and its principle of operation were introduced. Some key technologies that influence the system precision were also studied in details. Real-time image of work piece and wheel grinding can be gathered while using CCD camera. For image de-noising, a kind of wavelet threshold function was presented to calculate the new wavelet coefficients. Local threshold algorithm was used to compute different scale threshold, another threshold is suggested when MSE is minimum. Image signals are reconstructed through invert discrete wavelet transformation with the new wavelet coefficients. For the purpose of increasing the measurement precision, a closed mathematical model of sub-pixel edge detection operator was founded according to the gray moment operator’s invariant characteristics and Tabatabai’s first three sample gray moments. An application of system validity and the comparison results of work piece were also given. From experiments it can be said that the proposed method in this paper is effective, and its detection precision and results are reasonable.

This research is to investigate the dynamic characteristics of the grinding process. A kind of robust grinding wheel reciprocating arrangement is schemed out, which realizes the precise point-grinding machining. The grinding wheel reciprocating movement is driven by a linear motor to replace the traditional crank or hydraulic pressure drive device. Based on the time series method, the modal experimental analysis technique has been adopted in this paper. By acquiring acceleration signals of multiple positions of the grinding wheel slide, the dynamic characteristics are analyzed and the modal parameters of the structure are identified by virtual analysis program. The boundary condition of the finite element model is adjusted for optimizing its dynamic characteristic. The equivalent substructure is created and modified in order to improve the surface grinding quality. This study has got satisfying results. The grinding wheel movement realizes the self-regulation control and reduces the surface waviness and roughness during high speed point-grinding operation.

Present modeling algorithm for large-sized revolving parts’ camber can not ensure the smoothness, so a new modeling algorithm based on NURBS Curve was proposed in this study. In detail, the new modeling algorithm is as following: Firstly transfer these discrete points, which are measured along the part’s axial lead by equal distant, into a weighting unity sequence. Secondly filter this sequence by wavelet de-noising algorithm. Thirdly replace the discrete points’ amplitudes by the corresponding weights of filtered sequence, thus yield a group of new discrete points. Lastly calculate the control vertexes and weighting factors by local rational interpolation algorithm, and construct a spatial NURBS Curve through the new discrete points to obtain the model of large-sized revolving parts’ camber. It was experimentally confirmed that this model can represent drilling stem’s camber smoothly and improve its pressure straightening precision.

The experimental results for silicon carbide (SiC) wheel with fine grit size grinding of silicon carbide (Si3N4) revealed that the grinding parameters affect not only the ground silicon nitride surface roughness, but also the degree of surface damage. There exists complex non-linear relationship between the grinding parameters and surface quality. Better surface roughness doesn’t surely mean less surface damage. A method of prediction of grinding quality based on support vector regression is then presented according to the condition of small samples. The result shows the prediction accuracy based on this method is obviously higher than neural network, which provides an effective way for optimizing the grinding parameters to ensure the grinding quality as well as grinding efficiency while grinding of silicon carbide using conventional abrasive.

Ceramic coating materials own some advantages, for example high-rigidity, good abradability and good performance under high temperature. At the same time, ceramic coating materials are also difficult-to-machine materials. High machining precision and efficiency can be obtained in grinding WC-Co coating by cup wheel. The affection of grinding temperature is very important for grinding processing. But there is no research on grinding temperature of WC-Co coating by cup wheel. So in this paper, grinding temperature by cup wheel is researched on theory, the new concept, which is effectiveness width of arc moving heat source, is presented, and theoretical formula of grinding temperature is also built. Then experimental research on grinding temperature of WC-Co coating by cup wheel is done by use of thermocouple temperature measurement technology. The experimental results show the validity and effectivity of the theoretical formula. The affection of grinding parameters to grinding temperature is researched also.

This paper deals with an application for achieving precision curve grinding by automatic dressing and compensation of diamond wheel wear through non-contact measuring method. A realtime vision measurement combined with vibration analysis method for the wear of a grinding wheel is presented. The wear condition is evaluated by analyzing the topography changes of the wheel surface and the vibration signals in the grinding process. A kind of PC-based integrated control system with dynamic monitoring and automatic dressing function is investigated, and the control algorithm is also proposed. The benefits of the proposed methods are confirmed by the grinding experiments. Dynamic monitoring of the wheel facilitates determining the optimum dressing amount and interval. A much higher abrasive machining precision and efficiency are attained by the real-time error measurement and compensation arrangement.

In traditional NC curve grinding, the grinding wheel’s rotary surface is generally not on the grinding point’s normal direction, which will bring the distortion of grinding wheel and decrease the machining precision. This paper presents a new technology, which is called the non-interference normal tracking for NC curve grinding process. By controlling the worktable to rotate in the x-y plane, the superposition between the rotary surface of the grinding wheel and the normal vector of the workpiece’s contour is realized, and the interference between the wheel’s body and the workpiece could be avoided at the same time. A mathematic model is established and an algorithm to calculate the worktable’s rotary angle is proposed. Finally, the algorithm is applied in a new-type digital curve grinder successfully. The results show that the method is reliable and effective.

Both diamond wheel and CBN wheel belong to super-abrasive wheels. Diamond wheels have superior grinding performance. The metal-bonded diamond wheel can grind hard brittle material component with a complicated shape precisely and efficiently. Because dielectric liquid is forbidden on numerical control optical profile grinder, the information on profile truing and dressing diamond wheel mounted on numerical control optical profile grinder is not readily available. In this paper, a novel truing and dressing method, namely dry electrical discharge (dry-ECD) assisted truing and dressing, is proposed. The experiments of dry-ECD assisted profile truing and dressing of diamond wheel are done by the authors. The experimental results show that both geometrical accuracy and surface topography of diamond wheel have attained technical requirement under appropriate truing and dressing conditions. There is not much difference in grinding abilities of new diamond wheel and dry-ECD assisted truing and dressing diamond wheel.