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Based on digital coaxial holography image technology, a laser coaxial digital holographic tool setting device is built. The tool hologram was obtained by using the same laser and different power irradiation. The sharpest reconstruction image was obtained by using the focusing evaluation function of wavelet transform and piecewise-progressive search algorithm. Then, the improved self-snake filter was used to process the image, and the tool contour was extracted by using the Sobel operator. At the maximum threshold corresponding to the clear tool profile can be obtained, the tool profile under different laser power was compared. Finally the most suitable laser power for digital holographic tool setting device was obtained.

Antireflection functional surface has important applications in photoelectric detection, artificial blackbody, infrared imaging and other fields. In this study, the titanium alloy surface with high absorptivity was fabricated by nanosecond laser system. The effects of different scanning filling intervals on microstructure morphology and reflectance were studied. With the decrease of scanning interval, there are more and more micro clusters and micro holes on the surface, and the reflectance decreases gradually. When the scanning filling interval was reduced to 0.01 mm, the reflectance of titanium alloy surface could be decreased by 3% in the wavelength range of 400–1000 nm after laser treatment. In addition, in order to obtain a composite functional surface with superhydrophobic properties, the laser-processed surface was modified with a mixed solution of $1 H,\ 1 H,\ 2 H,\ 2 H$ -perfluorodecyltriethoxysilane and methanol. The maximum contact angle is 153.8° when the laser filling interval was 0.01 mm. It provides a reference for the preparation of antireflection and superhydrophobic composite functions surface.

Based on the research on the forming mechanism of textured PCD tool surface, the nanosecond laser is used to study the influence of laser machining parameters on the size and topography of PCD tool surface micro texture. The micro-hole texture is prepared on the surface of the PCD tool, and a single factor experiment is designed to study the influence of laser power, pulse frequency and defocusing amount on the micro-hole texture. The results show that, the micro-hole diameter increases gradually with the laser power, but decreases with the pulse frequency; the overall micro-hole diameter tends to increase with the defocus. The pulse frequency has the greatest impact on the micro-hole diameter, followed by the defocus amount, and finally the laser power. The influence of different parameters on the surface recast layer is also completely different. As a result, the surface and laser power are the main factors that affect the surface recast layer.

Formation characteristic of microbubble in a T-junction microchannel in polydimethylsiloxane (PDMS) microfluidic chip is investigated. Microbubble formation experiments are carried out to investiga...

Large-scale slender beam structures with weak stiffness are widely used in the aviation field. There will be a great deformation problem in machining because the overall stiffness of slender beam parts is lower. Firstly, the cutting mechanism and stability theory of the Ti6Al4V material are analyzed, and then the auxiliary support is carried out according to the machining characteristics of the slender beam structure. The feasibility of the deformation suppression measures for the slender beam is verified by experiments. The experimental analysis shows that on the basis of fulcrum auxiliary support, the filling of paraffin melt material is capable of increasing the damping of the whole system, improving the overall stiffness of the machining system, and inhibiting the chatter effect of machining. This method is effective to greatly improve the accuracy and efficiency during machining of slender beam parts. On the premise of the method of processing support with the combination of fulcrum and paraffin, if the tool wear is effectively controlled, the high precision machining of large-scale slender beams can be realized effectively, and the machining deformation of slender beams can be reduced. Although high speed milling has excellent machining effect on the machining accuracy of titanium alloy materials, severe tool wear is observed during high-speed milling of titanium alloy materials. Therefore, high-speed milling of titanium alloy slender beam is suitable to be carried out in the finishing process, which can effectively control tool wear and improve the machining accuracy of parts. Finally, the process verification of typical weak stiffness slender beam skeleton parts is carried out. Through the theoretical and technical support of the experimental scheme, the machining of large-scale slender beam structure parts with weak stiffness is realized.

GH4169 superalloy has excellent properties such as high strength, high hardness and high temperature resistance, and is widely used in aerospace, automobile manufacturing, defense industry and biomedical fields. In the cutting process of superalloy, there are some problems such as serious tool wear and poor surface quality. The placement of micro-pit arrays on the rake face of cemented carbide tools can effectively improve the friction and wear resistance of the tools and improve the cutting conditions. In this article, ABAQUS software is used to simulate the micro-pit array tool orthogonal micro-cutting GH4169 superalloy. The cutting simulation of GH4169 superalloy was carried out by using micro-pit diameters of 35 μm, 30 μm, 25 μm, 20 μm and non-texture, respectively. The cutting-chip contact state, cutting force, cutting temperature and chip shape during the cutting process were analyzed. The study found that the placement of micro-pit texture can effectively reduce the cutting force during cutting and improve chip breaking. The micro-pit texture can intercept debris and hard particles on the bottom surface of the chip, reducing scratches on the rake face of the tool and the furrow effect of the hard particles, effectively improving the wear resistance of the tool.

Plenty of experimental studies have shown that the performance of the cutting tools can be improved through fabrication micro-texture on the rake surface. In this paper, a nanosecond laser with wavelength of 1064 nm is used to create micro-holes on the rake surface of polycrystalline diamond (PCD) tool, the influence of laser process parameters (laser power, frequency and defocusing amount) on the diameter, depth and recast layer area of micro-hole is investigated by single factor and multi-objective optimization experiments. The diameter, depth and recast layer area of micro-hole are converted into a single gray correlation degree as the detection index of micro-hole quality by the gray correlation method combined with the principal component analysis. The mathematical model between laser process parameters and gray correlation degree (GRG) is established based on the response surface method (RSM), and the adequacy of the mode for gray correlation degree is studied by ANVOA, and the optimum process parameters are obtained and verified. The results show that the average relative error of the gray correlation model is 2.67%. Ultimately, the required micro-holes are prepared by laser power of 20 W, pulse frequency of 90 kHz, and defocusing amount of-0.5468 μm.

In this work, the localized electrochemical micro additive manufacturing technology based on the FluidFM (fluidic force microscope) has been introduced to fabricate micro three-dimensional overhang metal structures at sub-micron resolution. It breaks through the localized deposition previously achieved by micro-anode precision movement, and the micro-injection of the electrolyte is achieved in a stable electric field distribution. The structure of electrochemical facilities has been designed and optimized. More importantly, the local electrochemical deposition process has been analyzed with positive source diffusion, and the mathematical modeling has been revealed in the particle conversion process. A mathematical model is proposed for the species flux under the action of pulsed pressure in an innovatively localized liquid feeding process. Besides, the linear structure, bulk structure, complex structure, and large-area structure of the additive manufacturing are analyzed separately. The experimental diameter of the deposited cylinder structure is linearly fitted. The aspect ratio of the structure is greater than 20, the surface roughness value is between 0.1&ndash, 0.2 &mu, m at the surface of bulk structures, and the abilities are verified for deposition of overhang, hollow complex structures. Moreover, this work verifies the feasibility of 3D overhang array submicron structure additive manufacturing, with the application of pulsed pressure. Furthermore, this technology opens new avenues for the direct fabrication of nano circuit interconnection, tiny sensors, and micro antennas.

A robotically assisted catheterization system can obviously reduce the radiation exposure to the surgeon and lesson the fatigue caused by standing for long time in protective clothing. However, effective detection and feedback of proximal force signals is essential to the success of a surgery. This paper presents a compact, cost-effective force-sensing device based on strain gauges, for our team developed slave side, to measure the proximal force signals of the input catheter. A significant advantage is that the proposed sensing device can detect the force signals directly without any mechanical transmission, and this can increase the measurement accuracy of force information. In addition, a haptic interface based on MR fluid is designed to provide a realistic sense of operation according to the force signals from the slave side, so as to improve the safety and success of a surgery. Comparing experimental results from an insertion test and a load cell, show that the average error for force measurement is less than 0.01 N. This research provides important insights into the design of compact, ergonomic, robotic catheter manipulators for intraoperative navigation using effective tactile sensing devices.

A 51-year-old man presented with non-ST-elevation myocardial infarction due to extrinsic compression of the left main coronary artery (LMCA) caused by a dilated pulmonary artery (PA) with secondary pulmonary hypertension and was successfully treated with surgical intervention including pulmonary angioplasty, atrial septal defect correction, and thromboendarterectomy. Imaging modalities were extremely useful in making the diagnosis and providing follow-up of LMCA compression syndrome in this case. During the follow-up, a sufficient hemodynamic improvement was obtained, without exacerbation of the PA dilatation, resulting in the absence of compression of the LMCA.

The surface of the titanium alloy was blackened by a nanosecond pulsed laser, and two-dimensional and three-dimensional morphology observations and microstructure reflection measurements were performed by scanning electron microscopy (SEM), laser confocal scanning microscopy (LCSM) and microscopic angular resolution spectrometry (ARM). The effect of laser processing depth on reflectivity was studied by one-way filling scanning method. The results show that under different laser processing times, different microstructures are formed, and as the number of laser processing increases, the reflectivity of light decreases. In the 400–1000 nm band, the reflectance of the sample can be reduced to a minimum of about 1%.

In the process of ultra-precision machining, the tool-setting accuracy of the micro-milling tool is limited by the tool diameter. The accuracy of tool setting decreases with the decrease of tool diameter, which becomes an important factor for restricting the accuracy of ultra-precision machining. Based on the imaging principle of digital in-line holography, an efficient and non-contacted method for tool setting was proposed for improving the accuracy of tool setting. Aiming at the imaging problem of micro-milling tool, the evaluation function based on wavelet transform was introduced in the process of progressive search, so the optimal reconstructed image was accurately obtained through the autofocusing algorithm. Then the zero-order term and the conjugate image were eliminated via the self-snake diffusion. The tool contour was extracted by Sobel operator, and tool diameter was measured using different methods. Measurement results proved that holographic imaging can meet the requirements of in-position dynamic measurement for micro-milling tools, and also provided an important basis for the accuracy of tool setting.

In this work, a method for the fabrication of two- and three-dimensional curved surfaces with robust underwater superoleophobicity is reported for the first time on light alloys (including 5083 Al and TC4 Ti alloys) through the high speed wire electrical discharge machining (HS-WEDM). The surface morphology and compositions were characterized by scanning electron microscope and energy-dispersive X-ray spectrometer. The results showed that rough structures and a layer of oxidization were created on the light alloys by HS-WEDM cutting. The two- and three-dimensional structured curved surfaces after an ethanol immersion exhibited the extreme underwater superoleophobic property with the high oil contact angle and low oil sliding angle. More importantly, the underwater superoleophobic surfaces with the three-dimensional curved features could have many new applications. In order to use the potential functions, the durability of the fabricated samples was tested and the results showed that the samples still exhibited the underwater superoleophobic property after the underwater storage and physical mechanism tests. Additionally, this method is versatile, simple, environment-friendly, and cost-effective.

The interest of this article lies in the proposition of using bionic method to develop a new sound absorber and analyze the efficient of this absorber in a ski cabin. Inspired by the coupling absorption structure of the skin and feather of a typical silent flying bird &#8212 owl, a bionic coupling multi-layer structure model is developed, which is composed of a micro-silt plate, porous fibrous material and a flexible micro-perforated membrane backed with airspace. The finite element simulation method with ACTRAN is applied to calculate the acoustic performance of the multi-layer absorber, the vibration modal of the ski cabin and the sound pressure level (SPL) near the skier's ears before and after pasting the absorber at the flour carpet and seats in the cabin. As expected, the SPL near the ears was significantly reduced after adding sound-absorbing material. Among them, the model 2 and model 5 showed the best sound absorption efficiency and the SPL almost reduced 5 dB. Moreover, it was most effctive for the SPL reduction with full admittance configuration at both the carpet and the seats, and the carpet contribution seems to be predominant.

Titanium alloy has been widely used in the aerospace field due to its advantages of low density, high specific strength and high-temperature resistance. Its scope of application, however, has been narrowed down because of its high reflectivity to light. In order to maximize the potential, it becomes necessary to construct a surface light trapping structure of titanium alloy. Therefore, a simple and tunable method was introduced in this paper to fabricate antireflection microstructures on titanium alloy surface with the superhydrophobicity based on nanosecond laser. By optimizing the laser processing speed parameters, microstructured surfaces with low reflectance over the entire visible wavelength range and near-infrared region (400–1000 nm) can be obtained. Results indicate that when the scanning speed is 100 mm/s, the minimum reflectance in the 900–1000 nm wavelength range is less than 1%, and the total reflectance in the 500–1000 nm wavelength range stabilizes below 6%. In contrast, the surface of conventional titanium alloy absorbs only about 50% of the incident light, and the remaining 50% is reflected. Furthermore, treated surfaces demonstrate effective performance concerning hydrophobicity, with a maximum contact angle of 153.03°. The results show that the nanosecond laser can induce the anti-reflection and super-hydrophobic properties, and improve the absorption capacity of the surface.

To study the temperature of the cylinder block and cylinder head, temperature analysis was carried out for the engine based on FEM. The temperature and convection heat transfer coefficient boundary were obtained by CFD analysis. Then the engine temperature analysis was carried out by the software ANSYS and the accurate temperature field distribution is obtained which provides technical guidance for the performance improvement of each part of the engine.

As the demand for high speed and light weight of automobiles continues to increase, the requirements for power, volume and weight of the engine are also increasing. In the design and development of automobile engine cylinder head, the finite element analysis of its structural strength, stiffness and finite element model is used to analyze the static strength and finite element modal analysis of the cylinder head. The natural frequency and mode state of the cylinder head structure under the free mode and restrained mode are simulated and calculated, and the reliability of the structure is proved to be reliable. It provides a theoretical reference for subsequent casing design

Automotive air conditioning compressor bracket connects the compressor and engine, and make its long-term vibration in the bad environment, which will cause the compressor can't work smoothly, safely and reliably, therefore the design rationality of automotive air conditioning compressor bracket, directly affects the performance of air conditioning, in turn, affects the vehicle harshness (NVH) performance. So analyze the vibration performance of air conditioner compressor in the design phase is particularly important. This article analyzed the modal of the air conditioning compressor bracket based on the finite element method, and carried out the structure optimization for the bracket, and finally anticipated effect has realized for the mode improve.

With the development of the electricity industry in our country, the kinds and the quantities of electrical equipment are increasing quickly. When the electrical equipment is checked and evaluated, the recognition of equipment is very important. In this paper, based on gray level co-occurrence matrix to extract the texture of equipment, we proposed a way to identify the electrical equipment. First it uses the gray level co-occurrence matrix texture matching recognition of electrical equipment, and then adopts the method of fuzzy logic according to the result of the match on the classified recognition of electric equipment. By the experiments, the correctness and feasibility of identification method to the electrical equipment are proved.

Power equipment is of great importance to the power of things, the operation of equipment directly impact on the safety and stability of the power of things. Therefore, it is important to ensure secure and stable operation of the power grid by prejudging monitoring, observing and fault diagnosis of power equipment. A fault diagnosis method of power equipment based on the technology of power internet of things and KNN algorithm is proposed in this paper. Through the real-time sensing and data acquisition of the basic equipment status in power network operation, the equipment status is analyzed and prejudged, which can provide alarm signals of the equipment to avoid greater security risk.

Objective The aim of this study was to analyze the mid- and long-term outcome of single cusp replacement in patients with ventricular septal defect and aortic insufficiency. Methods From September 2005 through March 2014, 172 patients underwent single cusp replacement and ventricular septal defect (VSD) closure. The median age was 19.5 years (range, 9 months to 67 years). Additional techniques were used to repair associated anomalies including sinus of Valsalva aneurysm, patent ductus arteriosus, patent foramen ovale, subaortic membrane, and intramural coronary artery. Results One patient with large left ventricle (preoperative end-diastolic diameter: 9.8 cm) died after the procedure from incurable heart failure. Four patients required a second pump run for residual aortic insufficiency (AI) (two patients, 1.16%) and residual VSD (two patients, 1.16%). Four patients required re-exploration for postoperative bleeding or cardiac tamponade. Mean follow-up was 53.27 ± 25.37 months (median, 56.5 months; range, 3 to 104 months). Redo aortic valve surgery was performed in three patients. Three patients had moderate–severe AI during the following period without reoperation. There was no post-operative endocarditis. Conclusion Single cusp replacement can be safely used in patients with VSD-AI. doi: 10.1111/jocs.12543 (J Card Surg 2015;30:520–524)

A robotically assisted catheterization system can obviously reduce the radiation exposure to the surgeon and lesson the fatigue caused by standing for long time in protective clothing. However, few designs have taken the collision protection function of a catheter manipulator into consideration. Additionally, limited research has been conducted in the damage of the clamping mechanism to the catheter. This paper presents a novel clamping mechanism based on the electromagnetic braking for a catheter manipulator which can be used in the minimally invasive surgery training system. A significant advantage is that the proposed design has the collision protection function which can realize the relative sliding between the catheter and the clamping device so as to avoid the vessel puncture, when the measured force exceeds a certain threshold. In addition, the simulation verification of this function is carried out. The results show that the clamping force of the catheter obviously decreases when the measured force increases. This clamping mechanism provides important insights into the design of safe and reliable robotic catheter manipulators incorporating effective and lossless clamping for intraoperative navigation.

Surface roughness evaluation of a micro-milling surface using a 3D method can compensate for the deficiencies of the traditional 2D evaluation method, and improve the consistency and unity of the surface topography analysis. In order to obtain the reference plane for 3D roughness evaluation of a micro-milling surface, this study investigated the use of a bidimensional empirical mode decomposition algorithm (BEMD) to process the original surface data, and then use the frequency and energy information obtained by the data decomposition to determine the threshold for the evaluation criterion method. The simulation results showed that the method can effectively extract the reference plane, so that this approach can be extended to the evaluation of other machined surfaces.

Microbubble formation in a T-junction microchannel in polydimethylsiloxane (PDMS) microfluidic chip were developed. The experiment based on high-speed microscopic camera system was set up to investigate the effects of liquid flow rate, gas pressure and gas channel width on microbubble growth. Three stages of microbubble growth process were obtained through the experiment firstly. The control variable method was used for investigating the growth characteristics of microbubble, including volume change rate and the ratio of length to width. The present study provided an empirical reference for the growth of microbubble in microchannel, which helped to achieve precise control of microbubble volume.

As an important bearer communication network for smart power distribution and utilization sever, the terminal communication access network should satisfy the various quality of service (QoS) requirements. And the queue scheduling is one of the key technology in multi-service QoS support. In this paper, a queue scheduling algorithm based on buffer size is proposed to minimize the waiting time of emergency service. Simulation results show that the proposed algorithm could reduce the delay and packet loss significantly.

Microparts are widely used for aerospace, medical and other special industries. Due to the limitation of cutting tools and processing technology, and cost a lot, it is difficult to machining for conventional mechanical process especially for the micro holes in the materials with high strength and hardness. Yet it is a highly efficient machining process using micro-EDM, because of its non-contact mode. SUS 304 possess excellence corrosion resistance and heat resistance while it is hard to machine, this paper will do a series of research on the SUS 304 material about drilling micro holes using micro-EDM. From the comparative analysis of three different processes about drilling holes, it shows that using cutting edge electrode and layered milling processes effectively decrease the taper angle under keeping the precision of holes, the cutting edge electrode produces better material removal rate(MRR), and layered milling with different layered numbers have different influence on the machining performance.

In this paper, the micro-groove structure is designed on the surface of aluminum alloy by high speed wire cutting discharge machine (HS-WEDM). A multi-scale surface with micro structure was fabricated by this method. The paper design a series different groove spacing, groove depth and groove width and orthogonal design was using to analyze the relationship between the size of micro structure and the wettability of materials. The results show that the effect of the groove width on surface wettability is maximum, When the the groove spacing is 300μm, the groove depth is 100μm and the width of the groove is 230μm, the contact angle of the material surface is maximum, which is 155.98°. After observing the surface, it is can be known that the existence of groove structure can reduce the droplet and solid surface contact area greatly. In addition, these grooves sealed a plenty of air to increase the contact area of the droplet and the air that the solid surface are difficult to be wetted by droplets. It is feasible that realizing the change of the surface wettability by using optical combination.

RF excited capacitive coupled hollow cathode (CCHC) plasma source was developed for the fabrication of super smooth optics. The frequency of the RF power was 100 MHz, and the maximum power output was 150W. Optical emission spectroscopy (OES) was used to diagnose the argon plasma generated in the plasma polishing apparatus. Bispectral analysis was used to calculate the argon plasma temperature and electron density. The result shows that when the RF power changed from 40W to 120W the plasma temperature was between 1989K and 2200K. The electron density increased with the increment of the RF power.

The earth simulator is the most important testing equipment ground-based for the infrared earth sensor, and it is also a key component in the satellite controlling system. for three orbit heights 18000Km, 35786Km and 42000Km, in this paper we adopt a project of collimation and replaceable earth diaphragm and develop a high orbit collimation earth simulator. This simulator can afford three angles 15.19°, 17.46° and 30.42°, resulting simulating the earth on the ground which can be seen in out space by the satellite. In this paper we introduce the components, integer structure, and the earth's field angles testing method of the earth simulator in detail. Germanium collimation lens is the most important component in the earth simulator. According to the optical configuration parameter of Germanium collimation lens, we find the location and size of the earth diaphragm and the hot earth by theoretical analyses and optics calculation, which offer foundation of design in the study of the earth simulator. The earth angle is the index to scale the precision of earth simulator. We test the three angles by experiment and the results indicate that three angles errors are all less than ±0.05°.

In view of the serious problem of tool wear during micro-cutting process with high speed, implanting groove micro texture into the tool surface to enhance cutting properties consisting of reducing friction, exhausting heat, anti-sticking and anti-wearing based on non-smooth surface technology. Utilizing laser processing technology to machine micro groove texture in the tool surface. Performing micro-machined Al6061 alloy experiment with the high speed micro-turning experimental device which designed by own, and to evaluate cutting properties from three aspects are the chip form, the tool wear condition and the roughness of machined surface in respectively. The experimental results show that the groove micro texture have a good influence on improving wear resistance of the tool, the quality of machined surface and the chip form as well.

This paper put the microstructures of rice leaf surface as bionic object, grating micro-arrays were processed on 7075 aluminum alloy surface by high speed micro-milling machining (HSMM). The micromorphologies and hydrophobic properties of specimen surfaces were studied adopting scanning electron microscopy and contact angle (CA) goniometer, and analyzing its hydrophobic mechanism. Results show that hydrophobic surfaces is successfully fabricated only by building grating micro-array structures on aluminum alloy surface using HSMM without modifying any chemical substances, the contact angle on aluminum alloy surface increased maximally to 152. 83° from 63.27° before processing. Furthermore, the contact angle on specimen surfaces appear anisotropic wettability, which the contact angle difference of two direction is about 40°∼60°. In addition, the hydrophobicity and super-hydrophobicity on aluminum alloy surface is a coupling function result by both submillimetre regular grating arrays and many irregular nanoscale pits and projections distributing on submillimetre grooves surface.

In order to meet the demand of automation in high voltage transmission lines inspection and improve its precision, a remote distance inspection system is developed which is based on laser ranging and image processing technology. This system is used to detect the secure distance between transmission lines and object below it and scale of objects. Remote distance inspection system includes upper position computer and lower position machine. The lower position machine consisted of high revolution camera, two laser rangers, digital compass and GPS, these devices sent images, distance, attitude and location information to upper position computer. Measurement formulas derived from imaging principle. Upper position computer completes image process, measurement and other information management automatically. System structure is designed with light weight feature and total mass is 4kg, it is available on vehicle and unmanned aerial vehicle. System control software is developed with C++ language, inspection image and datum are recorded for the automated management. The system have been tested over a distance of 52m, 89m and 132m from objects, results show that the percent relative error is +1.9%, −2.2%, +2.9%, respectively. The high accuracy performance of this system is proved.

The research focused on the effect of the change in distance between adjacent centers and the size of the laser spots on the material temperature field. Aiming at the parameter optimization of pulse laser machining copper, the moving focus model based on heat conduction equation was introduced. And the finite element analysis software, COMSOL Multiphysics, was also utilized in the research. Without considering the phase transition process of copper, the results of the numerical simulation was shown in this paper. By the simulation study of copper’s irradiation with two adjacent pulses, the effect of the change in distance between adjacent centers and the size of the laser spots on the temperature field of the copper and the quantized results under the specific laser spot conditions were obtained simultaneously. Based on the results, several conclusions could be reached, when the laser spot size was small or the distance between adjacent centers is large, the mutual effect of the adjacent pulses could be ignored. When the spot size increased or the distance between adjacent centers decreased, the mutual effect got obviously. And the conclusions could be applied on the field of laser drilling, laser welding, etc. The former pulse’s temperature field was mainly used to increase the initial temperature of the later pulse’s affecting field, while the influence from the later pulse to the former one was slowing down the temperature decrease and reheating.

Objectives Minimally invasive cardiac surgery has recently become widespread. The aim of this study is to analyse the feasibility of a minimally invasive approach for coronary artery fistula (CAF) correction. Methods From February 2001 to June 2014, 49 patients in our centre underwent minimally invasive CAF correction without cardiopulmonary bypass (CPB). The mean age was 21.18 ± 11.24 years (range, 5 months to 64 years). Patients with cardiac anomalies who underwent CAF correction and those who underwent CAF via the minimally invasive approach with CPB were excluded. Results There were no in-hospital mortalities or conversions to median sternotomy. Subxiphoid incisions (22 cases) and parasternal incisions (20 cases) were the most commonly used approaches for the procedure. The operative time was 67.45 ± 22.69 min (30-125 min). The intubation time was 3.72 ± 1.82 h (2-12 h), and the ICU stay was 9.67 ± 5.43 h (4-24 h). A trivial residual shunt was identified in only 1 patient during the procedure; however, this shunt had disappeared by discharge. Conclusions The minimally invasive approach can provide excellent surgical exposure for CAF ligation in select patients. This approach is a safe and cosmetic alternative to conventional treatment and may minimize the length of stay.

In order to solve the problem that Camera Link standard interface used by the current industrial camera and image acquisition card could be realized only by making use of special integrated circuit, field programmable gate array (FPGA ) of Virtex5 series—the latest product of Xilinx was used, and at the same time very high speed integrated circuits hardware description language (VHDL) programming was used to realize logical sequence and signal control circuit of the Channel Link deserializer and the Frame Grabber on the Camera Link. Based on the bit error rate test and the integrity test of signal acquisition on at Camera Link, it was verified that the principle of system design was correct and acquiring normal image in the condition of high bit error rate was reliable. Thus, after applying designs of this system, resource transplantation was processed more effectively among the same series of FPGA, the hardware circuit was simplified, the development time was saved by more than 50%, and integration of the system was improved by 75%.

Aiming at the loading condition requirements of UAV platform, this paper designs the structure of the light-small opto-electronic stabilized platform assembled on UAV. By analyzing the requirement of frame structure, function and parameters of the opto-electronic stabilized platform, the structure of two axis and three frames is chosen; the separated outer frame design is adopted, and then they are optimized. This can decrease the difficulty of the assembly greatly and improve the precision of the whole platform. Then, this paper builds the opto-electronic stabilized platform model and dynamical simulation on it.

In this paper the rotating ultrasonic drilling is discussed as a new machining method to machine micro hole. It considerably improved the problems such as low entering drilling positioning accuracy, inferior hole dimensional accuracy and surface quality in current machining method. The machining characteristics discussed further proved the important meaning of the research of ultrasonic drilling. Due to the rotating movement introduced in ultrasonic drilling, there are many new technologies that are worth to study. This paper mainly discussed how the important component in ultrasonic drilling, the composite horn achieves resonance under different vibration sources of longitudinal vibration and torsional vibration, through which better machining effect and energy usage can be achieved.

This paper presents a new quartz accelerometer signal acquisition system in order to collect quartz accelerometers' current signal. In the system, we could transform current signal to voltage signal through precision sampling resistor. Then the analog voltage signal will be converted into digital signal by the high precision A/D chip AD 7732. In the case of small current, the system would also get the large voltage signal in the method of switching high-value resistors. This method makes full use of the A/D chip measurement range and enhances the precision of the system properly. The experimental results proved that the method of switching channel can improve the precision signal acquisition. This method enhances the precision of the accelerometer signal acquisition system to ±1×10−5 g when the current is small, which can satisfy the requirement of Inertial Navigation System.

A high-precision sensing system is designed for meso-scale friction test, which consists of laser, CCD and parallel plate-spring structures. Principles of micro-friction test and of sensing system are described in detail. Calibration experiments are carried out for sensing devices. The results show that the resolution of sensing system for friction testing can reach 10μN.

The purpose of this paper is to design and manufacture equipment for inspecting micro parts automatically. It can detect both sides of the part and complete turning and screening operations in the pipeline automatically. The Parametric models of the turn-over mechanism and screening mechanism are established by ADAMS in this paper, then the design variables of the models are studied to find out the optimal design parameters. The results are significant to the structural design and the use of the equipment. The optimization results show that the part's diameter is from 8 to 14mmand thickness is from 0.8 to 1.5mm, the inspection speed should be controlled below 300/min.

As improper installation for aspherical component will inevitably bring the tilt errors to the measured data, the reliability of measured data reduces. Considering that the characteristics of a general elliptic equation include information about direction and location, this paper presents a method based on ellipse fitting to remove tilt errors, which are included in the sampled data of meridian of aspherical component. The experimental results verify the reasonable and correctness of this method. Consequently, this method can effectively isolate the tilt errors from the measured data, simplify the detection method and improve the processing efficiency.

Small size and high speed motorized spindle is applied to Micro-machining and micro/meso-scale machine tools (mMTs). Usually, these spindles are compact and precise, rotation speed ranges from 40000 to 20000 rpm. In order to acquaint the performance, we investigated kinds of parameters of small size motorized spindle applied in a prototype meso milling machine which we are developing. The motorized spindle is analyzed in static and dynamic by ANASYS. Static rigidity, vibration characteristic, spindle deformation and natural frequency are calculated. These parameters are helpful in machine tool body design and performance improvement. We show a process how to simulate and calculate characteristic of the spindle by ANASYS and the meso milling machine is redesigned in terms of these data. Experiment results show that the small size spindle fulfills all the needs in application and the machine tool performance improve after redesign.

The forces acting on the rake and flank face are analyzed in details, through investigating the mechanism of the cutting surface formation according to the characteristics of micro-cutting. The relationship of rounded edge radius and cutting force is presented. The model of micro-cutting is established and the relationship between the cutting forces and the main parameters are obtained. The mechanism of micro-cutting is exploded theoretically, which is significant in cutting tools material choosing and cutting tools edge improving.

For the study between macro and micro friction force test and experimentation, a novel micro force testing apparatus is built up in this paper. In this apparatus the force sensing system is the key component, which determines the measuring accuracy and scope. The structure of force sensing system is designed and optimized on the basis of the theoretical calculation and finite element analysis. The sensing system is calibrated using the high-precision electronic balance. Results show that the deflection of force sensing structure is proportional to the applied force, which is consistent with the results of the theoretical calculation and finite element analysis.

A positioning system is established and tested for meso machine tools. The design aims to develop practical microscale machine tools, improve the capability in difficult-to-machine material processing, resolve the contradiction between small size and high torque output. In order to maintain a mini volume and in terms of nowadays technology, ball screw driven by AC motor is the only way to achieve high torque output. High grade components and control strategies are employed to grantee the system has an ideal accuracy. At first, the load is analysed and the mathematical models of moving platform and AC motor are setup, then the transfer functions in the control system are calculated. Also, the compact precision positioning system is stacked based on high performance motion control card, 20bit AC servo motor, high stiffness polish rod linear guideway and precision ball screw. Finally, experiments are conducted, and after an aborative adjustment, the precision positioning servo system can achieve: overall size 200mm, travel: 100mm, constant force: 200N, speed: 5rpm–2000rpm, resolution: 0.5µm, positioning error: ± µm.

The problem of conventional Kalman filter is that the model uncertainties will severly degrade the system performance. Because of that, the maximum likelihood estimator of innovation-based adaptive Kalman filter is studied in the paper. The improved algorithm is proposed in order to solve the limitation of ML adaptive estimator in the MEMS-INS/GPS integrated navigation system. The simulation results show that the improved algorithm is feasible and efficient.

This paper proposes an EO pump based novel type of micro fluidic control system, which can control both the output pressure and the output flow velocity. This system consists of an EO pump, a flow sensor, a pressure sensor and a fuel cell. By changing the driving voltage, the material of pipe and the two kinds of liquid, we get different output pressure and output flow velocity data. We proposed the mechanism using one fuel cell to solve the problem of gases generated by the EO pump. The characteristic evaluations have been carried out. The maximum flow velocity in the oil is 6.34µl/min at the driving voltage 7.02V.