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Magnetic gel abrasive finishing is a high-precision polishing method that uses magnetic forces to attract and restrain a gel abrasive, composed of aqueous slime gel, steel grits, and silicon carbon (SiC), for polishing workpieces. However, the magnetic adsorption performance of the gel abrasive will drop quickly when polishing non-ferromagnetic material such as stainless-steel or brass. Moreover, centrifugal force will push out the gel abrasive from the machining surface reducing the stability of polishing. Therefore, this paper developed a rotating cylinder-based magnetic finishing setup to allow the gel abrasive and workpieces to tumble and rotate together during the polishing process. To make the gel abrasive produce irregular and complicated movement paths for improving the polishing performance, this study first analyzed and compared the average surface roughness and removed material weight of workpieces using three kinds of motor operating modes, a unidirectional trapezoidal wave mode, a bidirectional sine wave mode, and a bidirectional trapezoidal wave mode. After identifying the best motor operating mode, the study further compared the polishing characteristics using several SiC particle and steel grit sizes. The experimental results showed that the rotating cylinder driven using a bidirectional trapezoidal wave could obtain better results for average surface roughness and removed material weight than the other two operating modes, while use of the larger steel grit size also obtained improved results. However, different silicon carbide particle sizes did not have a significant impact on the polishing characteristics.

Gear transmission is widely used in mechanical equipment. In practice, if the gearbox is damaged, it not only affects the yield rate but also damages other parts of machines; thus, increases the cost and difficulty of maintenance. With the advancement of technology, the concept of unmanned factories has been proposed; an automatic diagnosis system for the health management of gearboxes becomes necessary. In this paper, a compound fault diagnosis system for the gearbox based on convolutional neural network (CNN) is developed. Specifically, three-axis vibration signals measured by accelerometers are used as the input of the one-dimensional CNN; the detection of the existence and type of the fault is directly output. In testing, the model achieved nearly 100% accuracy on the fault samples we captured. Experimental evidence also shows that the frequency-domain data can provide better diagnostic results than the time-domain data due to the stable characteristics in the frequency spectrum. For practical usage, we demonstrated a remote fault diagnosis system through a local area network on an embedded platform. Furthermore, optimization of convolution kernels was also investigated. When moderately reducing the number of convolution kernels, it does not affect the diagnostic accuracy but greatly reduces the training time of the model.

Objective: To evaluate the clinical efficacy of warming acupuncture combined with joint mobilization for the treatment of scapulohumeral periarthritis. Methods: A search for published randomized controlled trials (RCT) investigating warming acupuncture combined with joint mobilization for the treatment of scapulohumeral periarthritis was performed using the Cochrane Library, PubMed, Embase, and Web of Science databases. According to requirements of the Cochrane systematic review, all evaluations of RCT investigating warming acupuncture with joint mobilization in the treatment of scapulohumeral periarthritis were performed via method quality assessment, data extraction, and data analysis. Revman 5.3 and Stata 12.0 statistical software were used for the meta-analysis, and the trial sequential analysis (TSA) software estimated the required information size for each outcome. Results: A total of 14 articles were retrieved for meta-analysis, which included 551 cases in the treatment group and 539 cases in the control group. Meta-analysis showed that: (1) warming acupuncture combined with joint mobilization improved total efficiency [OR = 6.16, 95% CI (3.79, 10.00), Z = 7.34; P < 0.001), TSA results confirmed the results of the meta-analysis; (2) warming acupuncture combined with joint mobilization improved the cure rate [OR = 2.84, 95% CI (2.19, 3.70), P < 0.001], TSA results revealed that no further tests were needed to verify; (3) warming acupuncture combined with joint mobilization reduced the number of treatments required for healing [MD = -7.49, 95% CI (-9.75, -5.23), P < 0.001], TSA results confirmed the results of the meta-analysis; (4) in comparing visual analog scale scores before and after treatment, meta-analysis result showed that: SMD = -2.01, 95%CI (-2.37, -1.65), P < 0.001, the difference was statistically significant, TSA results confirmed the results of the meta-analysis. Conclusion: Warming acupuncture combined with joint mobilization had a significant effect on the treatment of scapulohumeral periarthritis.

A Ni–Co compound (9:1) alloy of nanowires (NWs) synthesized by TiO2 nanotube templates was treated by N2/H2 annealing to enhance the immobilization of penta-histidine-tagged (5 × His-tagged) biotin. Based on the theory of immobilized metal affinity chromatography (IMAC), the chelator of transition, including Ni+2 and Co+2 metallic ions, was used to capture the 5 × His-tagged biotin by nanowire structure in this study. Physical properties and electrical resistivity in one dimension of annealed Ni–Co alloy NWs were characterized and then, the protein capture efficiencies were observed by measuring fluorescence intensities. By appropriate treatment on metallic Ni–Co NWs ligand surfaces, it was found that lower electrical resistivity combined with a higher saturation magnetic flux density (Bs) may be useful for immobilizing 5 × His-tag biotins. Furthermore, there is not only a higher contact probability but the surface-to-volume ratio of one dimensional Ni–Co alloy NW ligands proposes higher detected fluorescence sensitivity than that of Ni–Co film.

A fuzzy-PID controller design was proposed in this paper for a nanoscale platform positioning system. The target nanoscale X-Y platform is mounted on a pantograph mechanism and restricts the rotation by two small sliders; the device is driven by a traditional X-Y platform with common precision. The goal of this study is to drive the target platform’s movement in the region of 5 mm × 5 mm for the positioning, with repeated positioning accuracy error less than 200 nm by the traditional X-Y platform. Due to the different PID parameters affecting platform positioning accuracy and system response for the two axes, the fuzzy-PID controller will train to fit the mechanism to promote the positioning precision and path control effect. The simulation and experimental results indicated that the proposed method is feasible for nano-scale micro-platform positioning.

Purpose The purpose of this paper is to present the use of artificial immune systems (AISs) to solve constrained design optimization problems for active magnetic bearings (AMBs). Design/methodology/approach This research applies the AIS approach, more specifically, a representative clonal selection-based AIS called CLONALG, to the single-objective structural design optimization of AMBs. In addition, when compared with a genetic algorithm (GA) developed in the previous work, the CLONALG fails to produce best solutions when a nearly zero feasible ratio occurs in an AMB design problem. Therefore, an AIS called ARISCO (AIS for constrained optimization) is proposed to address the above issue. Findings A total of six AMB design cases are solved by the GA, CLONALG, and ARISCO. Based on the simulation results, in terms of solution quality, the ARISCO is shown to have better overall performance than the CLONALG and GA. In particular, when solving a problem with a nearly zero feasible ratio, the ARISCO and GA perform equally and both outperform the CLONALG. Originality/value In summary, the contributions of this paper include: this research applies the AIS approach, more precisely, the CLONALG, to the single-objective structural design optimization of AMBs; the ARISCO overall produces better AMB designs than the CLONALG and a GA developed in the previous work; in situations where a nearly zero feasible ratio occurs, the ARISCO and GA perform equally, and they both outperform the CLONALG.

The article describes the effect of a magnetic field applied to a ferrofluid&ndash, lubricated hydrodynamic journal bearing&ndash, rotor system. A rotor with a single journal bearing in one end was built to be the test rig. The experimental results showed that 3 to 8 permanent magnets, arranged by different methods, can all increase the instability threshold of the oil bearing. Especially, the magnetic field formed by eight magnets has the optimal effect. The whirl speed and the whip speed can be increased from 3024 rpm to 4480 rpm, and from 3184 rpm to 5268 rpm.

This study used ferrofluid as bearing lubricating fluid and added a magnetic field outside the bearing to test the effect on the oil bearing. The experimental results showed that magnets arranged by different methods can all increase the instability threshold of the oil bearing. Especially, the magnetic field formed by eight magnets has the optimal effect. The whirl speed and the whip speed can be increased to 4480 rpm and 5268 rpm.

A blood-typing assay is a critical test to ensure the serological compatibility of a donor and an intended recipient prior to a blood transfusion. This article presents a lab-on-disc blood-typing system to conduct a total of eight assays for a patient, including forward-typing tests, reverse-typing tests, and irregular-antibody tests. These assays are carried out in a microfluidic disc simultaneously. A blood-typing apparatus was designed to automatically manipulate the disc. The blood type can be determined by integrating the results of red blood cell (RBC) agglutination in the microchannels. The experimental results of our current 40 blood samples show that the results agree with those examined in the hospital. The accuracy reaches 97.5%.

Dye-sensitized solar cell (DSSC) is a potential candidate to replace conventional silicon-based solar cells because of high efficiency, cheap cost, and lower energy consumption in comparison with silicon chip manufacture. In this report, mixed-phase (anatase and rutile nanoparticles) TiO2 photoanode was synthesized to investigate material characteristics, carriers transport, and photovoltaic performance for future DSSC application. Field-emission scanning electron microscope (SEM), X-ray diffraction (XRD), photoluminescence (PL), and UV-visible spectroscopy were used to characterize mixed TiO2 particles. Subsequently, various mixed-phase TiO2 anodes in DSSC devices were measured by electrical impedance spectra (EIS) and energy efficiency conversion. The overall energy conversion efficiency of DSSC chip was improved as a result of the increase of rutile phase of TiO2 (14%) in anatase matrix. Synergistic effects including TiO2 crystallization, reduction of defect density level in energy band, longer lifetime of photoexcited electrons, and lower resistance of electron pathway all contributed to high efficiency of light energy conversion.

This study focused on the development of an intelligent motion control system for a nanoscale micro-platform based on the pantograph mechanism. The platform is designed to satisfy the need for achieving high accuracy and process efficiency in the manufacture of increasingly small industrial products. The target platform is mounted on a pantograph and small x-y sliders, and is driven by a traditional X-Y platform with common precision. The goal of this study is to drive the target platform to move in the region of 20mm × 20mm for the positioning, and repeatedly positioning accuracy error is less than 800 nm by a traditional X-Y platform. Due to the different PID parameters will affect platform positioning accuracy and system response for the two axes, the optimal PID parameters by the Genetic algorithms was proposed. The simulation and experimental results indicated that the proposed method is feasible for development of an intelligent motion control system for the nanoscale micro-platform positioning.

The Phenomenon of a Magnetic Controlled Ferrofluid Flow in the Flat Plate Laminar Flow System is Discussed in this Paper. the Ferrofluid Flow is One Kind of Colloid Mixture, which is Composited by the Magnetic Particles, Carrier Fluid and Surfactant. its Motion is Followed the Fluid Dynamics and can be Controlled by a Magnetic Field. from the Theoretic Analysis and the Experimental Test, the Coefficient of Viscosity of the Ferrofluid Flow will be Affected by the Magnetic Field. Thus, an Experimental Rig is Built to Test the Influences of the Gap of the Plate and the Strength and Direction of the Magnetic Field for Several Ferrofluid Flows with Different Dividing Rates of Volume. Experimental Results Showed that the Coefficient of Viscosity of the Ferrofluid Flow is Almost Not Upgrading in a Wide Gap Condition by the Magnetic Field, but as the Gap is Smaller, the Coefficient of Viscosity will be Promoted Obviously. Furthermore, Enhancing the Magnetic Field, it will be Increase the Coefficient of Viscosity of the Ferrofluid Flow. from the Experimental Results, the Relationship of the Magnetic Field, Coefficient of Viscosity of Ferrofluid Flow and the Carrier Fluid can be Confirmed.

An optical mechanism proposed in this paper is composed of a movable part and a fixed part for the increment high-resolution optical displacement encoders. A parallel light source is set on the moving part and a double-concave lens, a specially designed optical grating and a phototransistor array receiver are set on the fixed part. The parallel light emitted from the movable part passes through the double-concave lens and the specially designed optical grating; it is then projected onto the phototransistor array receiver to indicate the displacement of the movable part. The relationship equation of the lens is developed to design an optical mechanism, which can enlarge the displacement so that it becomes observable. Based on the simulation results, three different radii in the curvature of the double-concave lens were proposed. The simulation results indicated that the optical mechanism with 50 times magnification could make the 10 nm movement intervals of a light source be about 500 nm movement intervals in the detecting surface. Furthermore, considering the limitation of the precision of existing tools, an experimental system with a 200 nm resolution was established to verify the possibility of the proposed structure. The experimental result indicates the possibility of using the proposed theorem to achieve the desired results.

Dye-sensitized solar cell (DSSC) is a potential candidate to replace conventional silicon-based solar cells because of high efficiency, cheap cost, and lower energy consumption in comparison with silicon chip manufacture. In this report, mixed-phase (anatase and rutile nanoparticles) TiO2 photoanode was synthesized to investigate material characteristics, carriers transport, and photovoltaic performance for future DSSC application. Field-emission scanning electron microscope (SEM), X-ray diffraction (XRD), photoluminescence (PL), and UV-visible spectroscopy were used to characterize mixed TiO2 particles. Subsequently, various mixed-phase TiO2 anodes in DSSC devices were measured by electrical impedance spectra (EIS) and energy efficiency conversion. The overall energy conversion efficiency of DSSC chip was improved as a result of the increase of rutile phase of TiO2 (14%) in anatase matrix. Synergistic effects including TiO2 crystallization, reduction of defect density level in energy band, longer lifetime of photoexcited electrons, and lower resistance of electron pathway all contributed to high efficiency of light energy conversion.

An optical mechanism composed of a movable part and a fixed part for the increment high-resolution optical displacement encoders is proposed in this paper. The parallel light emitted from the movable part passes through a double-concave lens and a specially designed optical grating; it is then projected onto a phototransistor array receiver to indicate the displacement of the movable part. The relationship equation of the lens is developed to design an optical mechanism which can enlarge the displacement so that it becomes observable. Based upon the simulation results, a specially designed optical grating is designed to compensate for the deviations on the detecting surface and to derive the increment movement of the light source. The simulation results indicated that the optical mechanism with 50 times magnification could make the 10 nm movement intervals of a light source be about 500 nm movement intervals in the detecting surface. Furthermore, an experimental system with a 200 nm resolution is established to verify the possibility of the proposed structure.

This paper proposes a novel nano-scale micro-machining machine based on the pantograph mechanism. It is designed to satisfy the need for achieving high accuracy and process efficiency in the manufacture of increasingly small industrial products. The target platform is mounted on a pantograph and small x-y sliders, and is driven by a traditional X-Y platform with common precision. The theoretical and simulation results indicate that the proposed method is feasible for development of a micro-machining machine capable of achieving nano-level precision. In addition, test results indicate that the micro-machining machine can position the target platform with a resolution of 500nm

This paper presents a new switching control scheme for an active magnetic bearing (AMB) system using self-tuning fuzzy proportional-integral-derivative (PID) control. The research process consists of three stages. First, four types of self-tuning fuzzy PID-type controllers (FPIDCs) consisting of two most commonly used fuzzy inference systems: Mamdani and Takagi-Sugeno types, and two efficient parameter adaptive methods: function tuner and relative rate observer, are used to control a highly nonlinear AMB system, respectively. Hence, there are two kinds of FPIDCs can be obtained by comparing experimental results of these tests: one has the fastest transient response and the other has the minimum steady-state error. Next, the switching-type self-tuning FPIDC is proposed by combining the two kinds of FPIDCs. Namely, the AMB system is dominated by the scheme with the fastest transient response when the rotor is at rest and by the one with the best steady-state performance when the rotor is in rotation. Finally, experimental results demonstrate that the proposed switching-type self-tuning FPIDC performs better overall performance than the other self-tuning FPIDCs, particularly when controlling an AMB system.

A passive magnetic thrust bearing for a small vertical wind generator system is considered in this paper. The passive magnetic bearing is designed to reduce the axial load of the rotor system. The load capacity of the passive magnetic bearing is analyzed by finite element analysis software. From the simulation results, a suitable solution for the passive magnets of the test wind generator system is verified to be 225.6N with about a 2mm air gap. The experiment results show that a wind generator system with the additional passive magnetic bearing can start at a lower wind speed and transfers more power to the generator. The proposed hybrid bearing system can increase efficiency by 20%~50%, as compared with a traditional system supported by roller bearings at the same wind speed.

This paper deals with the unbalanced vibration problem of a stabilized active magnetic bearing (AMB) system. First, a model-based integral-type observer is proposed to evaluate the shaft displacement and the unbalancing forces of the rotor of an AMB system controlled by a proportional-integral-derivative (PID) controller. A fuzzy gain tuning mechanism is added to adjust the output of the PID controller in order to overcome the disturbances and suppress the unbalancing vibration. We have shown via simulation that the addition of the integral-type force observer improves the rotating accuracy in the device operating range. The experimental results demonstrate an efficient reduction of the shaft displacement of the rotor. Thus, the proposed scheme allows for a remarkable improvement in the unbalanced vibration of an AMB system over conventional PID controls without fuzzy gain tuning mechanism.

A novel optical displacement encoder was proposed in this paper. An optical mechanism was designed by the equations of thick lens to change and modify the paths of light, and then to get a more visible position change in the optical detector to improve the measurement accuracy. The simulation results indicated that the optical mechanism with 5 mm stroke, which the lens radii of curvature of the incident and the exit surface on the lens were -0.625 cm and 1.25 cm, respectively, and the magnification was 50 times in imaging distance of 38 cm, could make the 1 nm movement intervals of light source to be about 50 nm movement intervals in the detecting surface. Thus we can combine the optical mechanism and a photo-detector array with 50 nm resolution and 25 cm total detecting length to form the optical displacement encoder with 1 nm measuring accuracy.

This paper presents a design for a fuzzy gain tuning mechanism dealing with the problem of unbalanced vibration problem in an active magnetic bearing (AMB) system. For the purpose of enhancing the performance of the AMB system, we replace the conventional proportional-integral-derivative (PID) controller with a self-tuning fuzzy PID-type controller (FPIDC). The shaft displacement and the unbalanced forces of the rotor are evaluated by model-based observation. If there are model uncertainties in the rotor system or nonlinearities in the magnetic bearing system, this observer may not work well at any operating speed. A fuzzy gain tuner is added to adjust the actuating signal of the self-tuning FPIDC in order to overcome the disturbances and suppress the unbalancing vibration. The experimental results show that the proposed scheme allows for a remarkable improvement in reducing vibration in an unbalanced AMB system as well as demonstrate an efficient reduction in the shaft displacement of the rotor.

The paper proposes a novel time based brightness compensation circuit for LED back light modules. The brightness of LED decays while running under constant current driven condition. We have designed a suitable controller to compensate the driving currents to maintain the brightness. The compensation data were calculated from the relative luminous efficiency – time curve provided by the LED manufacturer and were stored in the microprocessor. -The embedded system used the running time of the LED in the back light module as an independent variable for tuning the driving current. The experiment results showed that the brightness of different operating times’ LED arrays can be held almost the same as the new ones.

Using TracePro® Monte-Carlo ray-tracing simulations, this paper investigates the improved light extraction efficiency (LEE) obtained by patterning the surface and/or substrate of GaN LEDs with unique three-dimensional micro-cavity patterns. The simulations commence by considering the case of a sapphire-based GaN LED. The effects on the LEE of the micro-cavity dimensions, the absorption coefficient of the active layer, the point source location, and the chip dimensions are systematically examined. Subsequently, the LEE performance of the sapphire-based GaN LED is compared with that of a thin-GaN LED for various surface texturing strategies. In general, the results show that patterning either the surface or the substrate of the LED structure provides an effective improvement in the LEE of both the sapphire-based GaN LED and the thin- GaN LED. For both LED structures, the maximum LEE enhancement is obtained by patterning both the upper surface of the LED and the substrate surface. However, the simulation results indicate that the improvement obtained in the LEE is the result primarily of pattering the upper surface of the LED.

A position command shaping controller, hybrid structure of feedforward controller and cross-coupling controller, for accurate contouring in motion control is proposed in this paper. The feedforward controller can improve tracking performance of single axis and the cross-coupling controller guarantees the reduction in contour error for multi-axis motion. When compared with the conventional motion system, this new structure has the advantage that the compensators have a simpler design process than conventional ones and so does its stability analysis. The proposed compensators (or controllers) are evaluated and compared experimentally with a traditional controller on a microcomputer controlled dual-axis positioning system. The experimental results show that the new hybrid structure reduces remarkably the tracking error and contour error. In addition, this new controller can be implemented easily on a majority of motion systems in use today via reprogramming the reference position command subroutine.

Objective: We aimed to determine the effect of neostigmine injections given at the Zusanli (ST 36) acupoint when treating postpartum urinary retention. Methods: We conducted a systematic review to identify randomized controlled trials (RCTs) involving neostigmine injections given at the Zusanli (ST 36) acupoint for treating postpartum urinary retention. We searched the Cochrane Library, Pubmed, Web of Science, Chinese National Knowledge Infrastructure, Vip Database, and Chinese Biomedical Literature Database from the creation of the database to December 30, 2016. Bias risk assessment was performed using Revman 5.3 software from Cochrane based on the criteria set out in the Cochrane Handbook for Systematic Reviews of Interventions, version 5.1.0. Results: Thirteen studies were included with 627 participants in the treatment group and 584 participants in the control group. (1) Overall response rate: neostigmine injections given at the Zusanli (ST 36) acupoint have a better curative effect than injections given in muscle, odds ratio (OR) = 8.74, 95% confidence interval (CI) [5.83, 13.10], Z = 10.49 (P < 0.001); (2) Comparison of effects at different dosages: (i) 0.5 mg of neostigmine Zusanli (ST 36) acupoint injection group has better effect than 1 mg of neostigmine intramuscular injection group, OR = 15.84, 95% CI [5.74, 43.72]，Z = 5.34 (P < 0.001), (ii) 0.5 mg of neostigmine injection given at the Zusanli acupoint has a better curative effect than 0.5 mg of neostigmine injection given in muscle , OR = 7.30, 95% CI [3.47, 15.34], Z = 5.24 (P < 0.001); (iii) 1 mg of neostigmine injection at the Zusanli (ST 36) acupoint has better efficacy than 1 mg of neostigmine injection in muscle, OR = 7.76, 95% CI [4.46, 13.52], Z = 7.25 (P < 0.001). Conclusion: Neostigmine injections at the Zusanli (ST 36) acupoint have beneficial effects in treating postpartum urinary retention. However, the low quality of the studies included in the meta-analysis raises questions over the reliability of the results. Further studies are still needed.

This study proposes design procedures for the permanent-magnet-biased magnetic bearings (PEMBs) in rotor systems. Many aspects of designing magnetic bearings are discussed, e.g. the selection of a permanent magnet material, dimensions of electromagnets and permanent magnets, gap length, load capacity and maximum Ampere-turns. Linearization and DC current driver are the two constraints for determining feasible designs. According to an analytical model with a rigid body assumption for the rotor-bearing system, a decentralized output feedback control algorithm is employed to control this inherently unstable magnetic suspension rotor system. Experimental results indicate that the controlled rotor performs well at rotor speeds up to 12,000 rpm.

Objectives: To determine whether traditional Chinese medicine (TCM) aerosol inhalation treatment is effective in the treatment of acute exacerbation of chronic bronchitis. Methods: Search double-blind randomised clinical trials (RCT) about the use of TCM aerosol inhalation in patient with acute exacerbation of chronic bronchitis via data base including Chinese biomedicine literature database, Wanfang Data, CNKI, Pubmed, EMBASE and Cochrane Library from the beginning to October 2016. Quality evaluation, data extraction and data analysis of these RCT was carried out with reference to the Cochrane systematic review. Results: 16 studies with 738 patients in TCM aerosol inhalation group and 675 in control group were included. The results of meta-analysis showed, (1) TCM aerosol inhalation group could improve the total cure rate. (2) TCM aerosol inhalation could increase the expression of IL-2 while decrease the expression of IL-8 and MDA in sputum and blood. (3) TCM aerosol inhalation could improve the symptoms of cough, cough with sputum, cough with dyspnea and lung wet rales. It also improve the symptoms of cough, expectorate and lung wet rales. (4) Shorten the time of cough and lung rale. (5) The adverse reactions were light only with 1 occurrence of nausea and vomiting. Conclusions: The use of TCM aerosol inhalation in the treatment of acute exacerbation of chronic bronchitis was effective. However, the inclusion researches quality were not very high, which only provided limited evidence for clinical application. Higher-quality randomized controlled trials were needed for further study.

The controller design for a permanent/electromagnetic magnetic bearing system that suspends a high-speed rigid horizontal rotor is investigated. The key points to ensure the stability of a rotor using this type of magnetic bearing are discussed. To facilitate implementation, a decentralized state feedback algorithm is proposed to stabilize the inherently unstable magnetic suspension system. Experimental results for the controlled system show that the system operates well at rotor speeds of up to 10,000 rpm.

In this paper we present a new controller design method that effectively suppresses vibration in flexible systems. The method allows integrated determination of sensor/actuator locations and feedback gain via minimization of an energy criterion which represents the integrated total energy stored in the system. This energy criterion is characterized by an effective representation of vibration, determined via an efficient solution of the Lyapunov equation and minimized with a quasi-Newton or recursive quadratic programming algorithm. The application of this method to a simple flexible structure confirms the direct relationship between our optimization criterion and effectiveness of vibration suppression.

A fuzzy imbalanced force estimator and feed-forward controller designed by the knowledge of rotor dynamics for a single active magnetic bearing suspended rotor system was proposed to eliminate the unbalancing vibration of rotor in the paper. The variable parameters used in the fuzzy estimator are displacement and velocity of the rotor and control current of the magnetic bearing. Based on the estimating signal, a feed-forward control system is set to suppress the unbalancing vibration. The simulation and experiment results show that the proposed estimation system could accurately estimate the unbalance force and the feed-forward control system could restrain the unbalancing vibration to improving the rotational accuracy.

Study objective: To assess the perceived impact of emergency medicine residency programs on other program directors' perceptions of emergency medicine as a distinct service and educational entity. Design: Self-administered questionnaire. Type of participants: Residency directors in medicine, surgery, pediatrics, and obstetrics and gynecology at sites containing emergency medicine residency programs. Results: Two hundred twenty-four of 372 questionnaires (60.1%) were returned completed, with equal distributions among all specialties. Respondents stated that the presence of the emergency medicine training program has positively influenced their attitude toward emergency medicine as a specialty (61% agree, 26% neutral), improved their residents' training in emergency medicine (47% agree, 31% neutral), and improved emergency care at their institution (65% agree, 26% neutral). Fifty-seven percent think emergency physicians should teach emergency medicine (27% were neutral). There were statistically significant associations between age of the emergency medicine program and perceived improvement in rotating residents' education and institutional delivery of emergency care. Conclusion: Residency directors in other specialties have a generally positive view of emergency medicine as a specialty and as an important component of their residents' education. The presence of an emergency medicine training program appears to have positively influenced their attitudes, improved their residents' education, and improved emergency care. Older programs have positively influenced attitudes to a greater degree than have newer programs.

To reduce the cost of LCD backlight unit (BLU) and raise efficiency, a direct LED BLU consisted of double-triangular structures was proposed to control the light from RGB side emitting LEDs. A genetic algorithm was used to search the optimal parameters of the shape of the double-triangular structures and the layout of the LEDs. A switch mode constant current control driver with a PWM controlled converter switch was used to maintaining the constant current output for the variable numbers of the LEDs in this paper. From the simulation results showed that without the diffuser, the brightness uniformity on the 25-point test was 93.44% for a 22" direct LED backlight unit with a thickness of 30mm with the optimized double-triangular structure. And the experiment result showed that the brightness uniformity and color uniformity were 85.61% and 0.021 for a small size test unit.

Adaptive variable structure controller was proposed to increase the robustness and decrease the influence of the disturbance for active magnetic bearings suspended turbomolecular pump in this paper. The model reference adaptive tuner was aimed to overcome the estimation error that is caused by the parameter uncertainty and the model uncertainty. The simulation results indicated that the turbomolecular pump suspended by active magnetic bearings with adaptive variable structure controller was successfully operated in wide rang, well resisted the unbalance or external disturbance during the rotational speed raising, and the amplitude of the displacement of system could quickly reach the center nearby when disturbance force was applied to the system suddenly.

A large size direct LED BLU consisted of double-triangular structures to control the light from RGB side emitting LEDs without the indispensable optical elements for the conventional direct LED BLU, such as the brightness enhancement film, diffuser sheet, and diffuser plate was proposed. A genetic algorithm was used in this paper to search the optimal parameters of the shape of the double-triangular structures and the layout of the LEDs to obtain optimum optical performances. Without diffuser and BEF, brightness uniformity of 91.87%, color uniformity of 0.042 and on-axis brightness increase of 50.23% for 22" direct LED backlight unit with a thickness of 30 mm with optimized double-triangular structure was obtained.

High power LED converter combined with switching power supply and current adjustment device for is presented. The switching power supply provides one stabilized voltage source, and the current adjustment device controls the output currents with a desired constant current and the over-load protection. The experiment results shows the circuit can work well and pass the load test and the electromagnetic interference test.

This study proposes a model-based force estimator with an adaptive tuner for a single active magnetic bearing suspended rotor system to eliminate the vibration associated with imbalance of mass. The adaptive tuner is added to the integral-typed observer to overcome the estimation error caused by the parameter uncertainty and the model uncertainty. Simulation results show that the adaptive estimation system is more accurate than the integral-type estimator, even though the system model has a 20% parameter error, and the feed-forward compensator can ameliorate the rotational accuracy in the operational range.