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This article investigates an observer-based optimal direct torque control (DTC) strategy for improving the transient and steady-state performance of surface-mounted permanent magnet synchronous motor (SPMSM) drives. Unlike conventional DTC techniques, the proposed method simultaneously controls speed, torque, and flux variables by employing the optimal control theory in the stationary reference frame. This helps achieving a simple structure along with good low-speed operation as the stator flux angle need not be estimated. Further, the feedforward control terms are designed to compensate for system uncertainties. Additionally, an in-depth stability analysis is presented through the Lyapunov theory. Comparative results via a real-time prototype SPMSM test-bed with TI-TMS320F28335 DSP indicate improved performance of the proposed optimal DTC compared to conventional PI DTC, nonlinear optimal DTC, and adaptive DTC, including less computational burden, less torque and flux ripples, more robustness to parameter uncertainty, and improved transient response under very low speed/load step-changes and speed reversal.

All-inorganic materials, mixed halide perovskite (MHP) nanocrystals (NCs), have attracted considerable attention recently because of their excellent luminescence efficiencies and extraordinary physical properties, making them a promising material for next-generation lighting and full-color display. On the other hand, an essential development of blue-emitting devices rather than other color emitters has been hindered by their defect tolerance and quantum efficiency which are relatively lower than those of green-emitting NCs. Moreover, few studies have examined the synthesis and properties of blue-emitting MHP NCs or their applications to light-emitting diodes (LEDs). To solve these problems, this paper reports a facile and controllable way of producing emission wavelength tunable CsPb(Br1−xClx)3 NCs using a fast and straightforward chemical treatment with the trimethylsilyl chloride (TMSC) additive. Structural and chemical analysis showed that the Cl content in the CsPb(Br1−xClx)3 NCs could be modulated by TMSC addition without changing the morphologies. The photoluminescence emission peak wavelength of the CsPb(Br1−xClx)3 NCs could be modulated from 515 to 416 nm by increasing the TMSC content. To this end, blue and green LEDs were successfully demonstrated by using the TMSC-treated CsPb(Br1−xClx)3 NCs as an emissive layer, showing a controllable emission wavelength from 473 to 511 nm.

In this letter, a probe-fed reconfigurable dual-/triple-band circularly polarized (CP) Spidron fractal dielectric resonator antenna (SFDRA) is proposed. Initially, a dual-band CP SFDRA is designed. An eigen-mode simulation of an isolated SFDR concludes that the quasi-TM $_{11\delta }$ and quasi-TM $_{21\delta }$ are excited in the lower band, whereas the quasi-TE $_{12\delta }$ mode is excited in the upper CP band. The modes of the lower CP band are separated by etching a T-shaped slot from the ground plane, thereby achieving overall triple-band circular polarization. In addition, the TSS being $\lambda _g/2$ in length at 2.64 GHz produces a band-notch function. CP band reconfigurability is attained by placing a diode D1 across the width of the TSS such that the on -/ off -state of the D1 radiates dual-/triple-band CP waves. The measurement results in the on -[ off ]-state show the impedance bandwidths for $\mathopen |$ $S_{11}\mathclose | $-$ 10 dB of 57.60% (2.2–3.98 GHz) [14.44% (2.12–2.45) and 40.48% (2.64–3.98 GHz)] and the 3 dB axial-ratio bandwidths of 24% (2.31–2.94 GHz) and 6.82% (3.68–3.94 GHz) [6.34% (2.29–2.44 GHz), 6.65% (2.76–2.95) and 7.09% (3.67–3.94 GHz)] in an ascending order of the frequency. A reasonable match is observed between the simulated and experimental data.

This paper proposes the variable regularized affine projection algorithms (VR-APAs) for the online multiparameter estimation of the interior permanent magnet synchronous motors (IPMSMs). Unlike the conventional APAs with a fixed regularization factor, the normalized gradient of the mean-square error is introduced in the proposed VR-APA to update the variable regularization which ensures a fast convergence rate, accurate estimation, and low steady-state error. Moreover, the proposed VR-APA does not require any accurate priori information of the motor parameters, making it highly feasible for the IPMSM. In order to accurately estimate the stator d–q axis inductances, stator resistance, flux linkage, and load torque, the two-time scale approach in the proposed VR-APAs is used due to the difference in the IPMSM dynamics. Of various applications of the proposed VR-APAs, such as condition monitoring, fault analysis, and controller design, these estimated multiparameters are updated online to the adaptive decoupling PI controllers to achieve the robustness against the parameter variations due to the temperature increase and load disturbances under various operating conditions (i.e., speed change, load change, and speed reversal). Finally, the comparative experimental verifications via a prototype IPMSM with TMS320F28335 DSP programmed by Code-Composer-Studio are conducted to confirm the effectiveness of the proposed VR-APAs.

Environment maps must first be generated to drive mobile robots automatically. Path planning is performed based on the information given in an environment map. Various types of sensors, such as ultrasonic and laser sensors, are used by mobile robots to acquire data on its surrounding environment. Among these, the laser sensor, which has the property of being able to go straight and high accuracy, is used most often. However, the beams from laser sensors are refracted and reflected when it meets a transparent obstacle, thus generating noise. Therefore, in this paper, a state-of-the-art algorithm was proposed to detect transparent obstacles by analyzing the pattern of the reflected noise generated when a laser meets a transparent obstacle. The experiment was carried out using the environment map generated by the aforementioned method and gave results demonstrating that the robot could avoid transparent obstacles while it was moving towards the destination.

This paper proposes a finite control set model predictive control (FCS-MPC) to guarantee the stability and robustness for surface-mounted permanent magnet synchronous motor (SPMSM) drives. Continuous-input-based control laws are first developed from a control-Lyapunov function in order to both stabilize the closed-loop system via feedback control laws and ensure the robustness via online adaptive laws. Because the asymptotic stability of the proposed control method is guaranteed by at least one discrete switching-state, the continuous-input-based control laws are converted into relevant constraints of the FCS-MPC optimization problem. To validate the advantages of the proposed FCS-MPC, comparative studies with the conventional FCS-MPC and space vector modulation based adaptive control are conducted on a prototype SPMSM testbed with a TI TMS320F28335 DSP. The effectiveness of the proposed FCS-MPC is verified by the comparative schemes with/without the additional constraints. Superiority of the proposed schemes such as zero steady-state error, fast speed-tracking capability, well-regulated stator currents, and low average switching frequency are experimentally validated under the step-changes of load torque and speed reference.

In this paper, we present a directional antenna-based leader–follower robotic relay system capable of building end-to-end communication in complicated and dynamically changing environments. The proposed system consists of multiple networked robots — one is a mobile end node and the others are leaders or followers acting as radio relays. Every follower uses directional antennas to relay a communication radio and to estimate the location of the leader robot as a sensory device. For bearing estimation, we employ a weight centroid algorithm (WCA) and present a theoretical analysis of the use of WCA for this work. Using a robotic convoy method, we develop online, distributed control strategies that satisfy the scalability requirements of robotic network systems and enable cooperating robots to work independently. The performance of the proposed system is evaluated by conducting extensive real-world experiments that successfully build actual communication between two end nodes.

A desire for renewable alternatives to fossil fuels can be achieved by utilizing CO2, H2O, and solar energy to generate solar fuels. A novel N-doped graphene oxide enfolded reduced titania (NGO-RT) composite was demonstrated for photocatalytic CO2 reduction into CH4. Later, a small amount of Pt NPs was deposited on NGO-RT that increases the catalytic performance towards CH4 formation. The optimized Pt1.0%-NGO-RT catalyst displayed a selective visible-light CO2 reduction into CH4 using a flow reactor system with ≈12 and ≈2 times higher activity than pristine RT and NGO-RT, respectively. The catalyst demonstrated long-term stability over 35 h. The photo-induced CO2 reduction mechanism was first validated through the electron transfer process, where charge trapping by Ti3+ states near the conduction band of RT plays a vital role in the selective CH4 evolution. These trapped electrons transfer from RT to the closely connected interface of N-doped graphene oxide and Pt NPs to restrict the recombination of electron/hole pair. The improved catalytic performance can be attributed to RT’s downward band bending at the NGO-RT interface, where electron transfer from RT to NGO decreases the charge recombination.

This paper proposes a fuzzy model predictive direct torque control (FMP-DTC) strategy of interior permanent magnet synchronous motors (IPMSMs) for electric vehicle (EV) applications. The fuzzy logic control technique incorporated into the proposed FMP-DTC scheme dynamically determines the appropriate values of the weighting factors, and then generates the optimal switching states that minimize the electromagnetic torque and stator flux errors. Unlike the conventional model predictive (MP)-DTC strategy, the optimal switching states of the proposed FMP-DTC are selected without retuning the weighting factors. It means that they are updated depending on the specific operating conditions. Therefore, the proposed FMP-DTC is effective in various operating conditions that make it suitable for the EV-traction operating environment. Hence, the proposed FMP-DTC method has a simple control structure and can explicitly handle the system constraints. The performance evaluation is carried out via both MATLAB/Simulink and a prototype IPMSM test-bed with a TMS320F28335 digital signal processor (DSP). Comparative simulation and experimental results present the evidence of the performance improvements based on the proposed FMP-DTC strategy compared with the conventional MP-DTC strategy by indicating a fast transient torque response, low ripples, and an accurate speed tracking even under rapid climbing or emergency braking situations.

This paper proposes an online identification method that can accurately estimate the stator resistance and dq -axis stator inductances for the effective model-based sensorless control of interior permanent magnet synchronous motors (IPMSMs). The proposed affine projection algorithms are uniquely designed in the estimated rotating γ-δ frame to precisely identify the parameters mentioned above. The two time-scale approaches are employed in the affine projection algorithms to estimate the three electrical parameters. Despite the electrical parameter variations due to the temperature change and magnetic saturation during operation, the rich enough data are provided to the affine projection algorithms in the discrete-time domain to accurately retrieve the updated parameters. These correctly estimated parameters are adapted to the extended back electromotive force observer for the sensorless control of IPMSM drives. Hence, the adaptation of online updated parameters makes the observer stable and robust to parameter variations as compared to the conventional observer without updated parameters. The MATLAB/Simulink-based simulation results and experimental results via a prototype IPMSM test-bed having TMS320F28335 DSP are given to verify the accurate convergence of the estimated parameters, which results into a stable sensorless control system under various operating conditions.

This paper proposes an effective protection strategy which combines three-crowbar circuit configuration (TCCC), a small bypass resistor (SBR) for wind turbines (WTs) based on the doubly fed induction generators (DFIGs). The TCCC includes (i) resistive crowbar, (ii) inductive crowbar, and (iii) capacitive crowbar. Conventionally, applying only resistive-crowbar circuit as the only means of protection on the DFIG WT, the rotor-side power converter (RSPC) and dc-link capacitor are protected against the effects of a severe voltage dip. However, tripping the RSPC leads to loss of excitation control, and the DFIG behaves like the squirrel-cage induction generator which obtains its magnetization current from the grid which further deepen the terminal voltage. Moreover, integrating the resistive crowbar with series R–L branch keeps the RSPC connection active, but the generator excitation control is partially retained and the oscillations of the rotor currents and dc-link voltage can heavily deteriorate the performance of the generator. Thus, the TCCC-SBR circuit is proposed to compensate for the deficiency when the two conventional circuits are applied. Its performance validation is performed via extensive simulation studies using MATLAB/Simulink software. From the comparative simulation results, more improved fault ride-through capability of the DFIG is achieved with the proposed protection circuit than the conventional protection circuits.

This paper designs a predictive speed controller of interior permanent-magnet synchronous motor (IPMSM) based on finite control set (FCS)–model predictive control (MPC). The proposed predictive speed controller has a cascade-free structure that comprises a single predictive control function for the speed and dq- axis stator currents. The future rotor speed and stator currents are predicted at each sampling interval. Then, the proposed predictive control function is evaluated to determine the optimal switching states for the IPMSM drive. In high-performance speed-controlled drive, the unknown load torque disturbance has to be suppressed. Therefore, the load torque disturbance estimator using the two-stage extended Kalman filter (TSEKF) is proposed to enhance the dynamic performance of the IPMSM drive. The proposed TSEKF simultaneously estimates the system states, which greatly improve the model prediction process. The proposed predictive speed control is simple and compact, which demonstrates a faster transient response and a robust feature to mechanical system parameter variations when compared with the conventional cascaded speed control under a wide speed range and load torque variations. The experimental results on a prototype IPMSM drive built on a Texas Instruments TMS320F28335 floating point digital signal processing (DSP) board are presented considering the constant torque and flux-weakening regions to confirm the feasibility of the proposed FCS-MPC scheme.

This paper proposes a crowbarless low-voltage ride-through (LVRT) scheme for doubly-fed induction generator (DFIG) based wind turbines (WTs). The proposed strategy avoids the engagement of a crowbar circuit by utilizing the PI controllers with modified feed-forward compensators (MFFCs) and series R-L circuit. The series R-L circuit is inserted between the rotor-winding terminals and the ac-side of rotor-side power converter (RSPC) when the rotor overcurrent exceeds its threshold value during faults. Conventionally, the RSPC cannot generate the required excitation voltage due to its small ratings when the DFIG experiences a voltage deficiency following the occurrence of a grid fault. Thus, both the MFFCs and series R-L circuit are implemented to not only correct the conventional feed-forward compensators of the PI controllers for the back-to-back converters but also limit the rotor overcurrent and dc-link overvoltage to within their threshold values. In so doing, the fluctuations seen on the active and reactive powers responses are also automatically restricted, which ensures the smooth transitions. Also, the DFIG’s reactive power control is modified to stably support the point of common coupling (PCC), i.e., DFIG terminal voltage. Comparative studies with five grid-code requirements are performed for a wind farm with 15 WTs to demonstrate the LVRT performances of the proposed scheme and conventional schemes using MATLAB/Simulink software.

In this paper, we suggest an automated method for counting sperms using sequential microscopic image captured from the smartphone and additional microscopic lens. First, ROI image is created and then converts to the binary image. Using the previous frame, this binary image creates the subtraction image. After labeling of the subtraction image, counting the number of sperms is possible by the characteristics of microscopic image. Experimental results show that the results from the proposed algorithm is meaningful in the criteria from WHO standards.

This paper designs a feedback linearization direct torque control (FL-DTC) based on the space vector modulation (SVM) which can noticeably reduce the electromagnetic torque and stator flux ripples that affect the system efficiency on interior permanent magnet synchronous motor (IPMSM) drives. First, a decoupled linear IPMSM model with two state variables (i.e., the stator flux and electromagnetic torque) is derived to implement the proposed FL-DTC strategy that preserves some advantages such as fast torque control, high torque at low speed, and fast speed response. Also, the proposed technique greatly alleviates the torque and stator flux ripples which are the major concerns of the classical hysteresis-based DTC scheme and have an effect on the stator current distortion. The system stability with the designed FL-DTC method is mathematically analyzed using the Lyapunov stability theory. Finally, the effectiveness of the proposed control law is validated through simulation results with MATLAB/Simulink and experimental results obtained from a prototype 1-HP IPMSM drive with TI TMS320F28335 digital signal processor (DSP). The verification results demonstrate that the proposed FL-DTC scheme achieves faster torque response, smaller torque ripple, and lower stator flux ripple than the conventional SVM-based PI-DTC approach under parameter uncertainties and external disturbances.

This paper proposes an online parameter estimation method based on a discrete-time dynamic model for the interior permanent-magnet synchronous motors (IPMSMs). The proposed estimation technique, which takes advantage of the difference in dynamics of motor parameters, consists of two affine projection algorithms. The first one is designed to accurately estimate the stator inductances, whereas the second one is designed to precisely estimate the stator resistance, rotor flux linkage, and load torque. In this paper, the adaptive decoupling proportional–integral (PI) controllers with the maximum torque per ampere operation, which utilize the previously identified parameters in real time, are chosen to verify the effectiveness of the proposed parameter estimation scheme. The simulation results via MATLAB/Simulink and the experimental results via a prototype IPMSM drive system with a TI TMS320F28335 DSP are presented under various conditions. A comparative study with the conventional decoupling PI control method is carried out to demonstrate the better performances (i.e., faster dynamic response, less steady-state error, more robustness, etc.) of the adaptive decoupling PI control scheme based on the proposed online parameter estimation technique.

This paper proposes an analytic model for four-switch inverter (FSI)-driven wye (Y) or delta (Δ)-connected motors with a current ripple reduction algorithm. FSIs employ four switches in controlling three-phase load instead of using six switches. They have split dc-link stage, and due to this inherent structure there exists the voltage difference between upper and lower capacitors, which results in distortion of the inverter output voltage. To study characteristics of FSIs, this paper presents an advanced simulation models of FSI-driven control system for 3-phase motor that can has a wire connection either Y or Δ. In addition, this paper introduces a current ripple reduction scheme that mitigates degradation of control performance due to the voltage difference between the dc-link capacitors. The validity of the proposed method and the analytic model is verified by simulations and experiments carried out with 1-HP induction machine with Y or Δ-connection

Atomically thin transition metal dichalcogenides (TMDs) have recently attracted great attention since the unique and fascinating physical properties have been found in various TMDs, implying potential applications in next-generation devices. The progress towards developing new functional and high-performance devices based on TMDs, however, is limited by the difficulty of producing large-area monolayer TMDs due to a lack of knowledge of the growth processes of monolayer TMDs. In this work, we have investigated the growth processes of monolayer WS2 crystals using a thermal chemical vapor deposition method, in which the growth conditions were adjusted in a systematic manner. It was found that, after forming WO3-WS2 core-shell nanoparticles as nucleation sites on a substrate, the growth of three-dimensional WS2 islands proceeds by ripening and crystallization processes. Lateral growth of monolayer WS2 crystals subsequently occurs by surface diffusion process of adatoms. Our results provide understanding of the growth processes of monolayer WS2 by using chemical vapor deposition methods.

This paper presents a nonlinear optimal direct torque control (DTC) scheme of interior permanent magnet synchronous motors (IPMSMs) based on an offline approximation approach for electric vehicle (EV) applications. First, the DTC problem is reformulated in the stationary reference frame in order to avoid estimating the stator flux angle, which the previous DTC schemes in the rotating stator reference frame require. Thus, the proposed DTC method eliminates the Park's transformation, and consequently, it reduces the computational efforts. Particularly, since the estimated stator flux angle is not accurate in low speed range, the proposed method that does not need this information can significantly improve the control performance. Moreover, a nonlinear optimal DTC algorithm is proposed to deal with the nonlinearity of the IPMSM drive system. In this paper, a simple offline θ- D approximation technique is utilized to appropriately determine the controller gains. Via an IPMSM test bed with a TI TMS320F28335 DSP, the experimental results demonstrate the feasibility of the proposed DTC method by accomplishing better control performances (e.g., more stable in low speed region, much smaller speed and torque ripples, and faster dynamic responses) compared to the conventional proportional-integral DTC scheme under various scenarios with the existence of parameter uncertainties.

This paper presents an over-review of various strategies applied to enhance the fault ride-through (FRT) capability of the doubly-fed induction generators (DFIGs) based wind turbines (WTs) during transient-state. As the DFIG based WT system is sensitive to any grid disturbance, various FRT techniques based on: (i) installation of additional protection circuits, (ii) installation of reactive power injecting-devices and (iii) specific control approaches/structures have been proposed in the literature. Usually, the protection circuits or control structures are applied to limit the generated rotor over-current and undesirable dc-link over-voltage during grid disturbance. Meanwhile, the reactive power injecting-devices surpass any deficiency of the reactive power so as to improve the transient performance of the DFIG based WT and automatically bound the rotor current and the dc-link voltage. Actually, many research findings demonstrate an efficient protection of the DFIG without jeopardizing its operating strategy during transient-state. Therefore, this study focuses on emphasizing the present status of the rotor over-current and dc-link over-voltage protection solutions e.g. the crowbar and its related protection circuits, the reactive power injecting-devices such as the static synchronous compensators (STATCOM) and dynamic voltage restorer (DVR). Moreover, some control (modified) approaches/structures for limiting the inrush rotor currents which are based on linear and nonlinear control strategies are presented. Following the description of the overall system characteristics under steady-state and transient-state in the d–q axis, various protection strategies are extensively discussed to reveal their role to improve the FRT. Then, typical case studies are presented to demonstrate and support the reviewed FRT schemes. In that case, using the simulation results from the MATLAB/Simulink software the effectiveness of each case study during network faults are analyzed and compared.

This study is a part of ongoing research conducted to develop an ideal implant for augmentation rhinoplasty using a combination of cartilage tissue engineering and 3D printing (3DP) techniques. A promising nasal implant-shaped (NIS) scaffold for rhinoplasty should have flexibility similar enough to native cartilage tissue to maintain its mechanical stability after implantation into a nose. In scaffold fabrication using 3DP, the pore pattern or architecture has a significant effect on the mechanical properties of a scaffold. In this study, we proposed octahedron pore architecture inspired by a zigzag spring, which stores more mechanical energy than a simple rod. Therefore, we assumed that the scaffold having octahedron pore architecture is more flexible than one that has the cube or lattice pore architecture that is widely used in tissue engineering based on 3DP. To verify this assumption, scaffolds having octahedron, cube, or lattice pore architecture with the same porosity and same unit cell size were fabricated using projection-based micro-stereolithography and sacrificial molding, and their mechanical behaviors were analyzed using compression and three-point bending tests. Compared to the other pore types, the octahedron pore architecture had superior flexibility, which is beneficial for clinical application of NIS scaffolds.

Byeung-Leul Lee Seung-Jae Lee Dae-Joong Moon Jin-Woo JungAbstractIn this study, an efficiency test was performed by fabricating MEMS (Micro Electro Mechanical Systems) based 3-axis acceleration sensor modules and an earthquake monitoring system was composed. Data acquisition device (NI-9239) with a 24bit ADC (Analog to Digital Converter) was used for improving the performance of 3-axis acceleration sensor modules and filtered data (100Hz Low Pass Filter) was used for reducing noises. Also this paper focused on detecting meaningful vibration in the building by developing the earthquake monitoring software. If vector sum of 3-axis acceleration is greater than the preset value, the value will be recordedand saved to the file.Keywords : Dynamic range, Earthquake monitoring system, MEMS sensor, Vector sum, 3-axis accelerometer

Aims: Abnormal accumulation of α-synuclein aggregates is one of the key pathological features of many neurodegenerative movement disorders and dementias. These pathological aggregates propagate into larger brain regions as the disease progresses, with the associated clinical symptoms becoming increasingly severe and complex. However, the factors that induce α-synuclein aggregation and spreading of the aggregates remain elusive. Herein, we have evaluated the effects of the major lipid peroxidation byproduct 4-hydroxy-2-nonenal (HNE) on α-synuclein oligomerization and cell-to-cell transmission of this protein. Results: Incubation with HNE promoted the oligomerization of recombinant human α-synuclein via adduct formation at the lysine and histidine residues. HNE-induced α-synuclein oligomers evidence a little β-sheet structure and are distinct from amyloid fibrils at both conformation and ultrastructure levels. Nevertheless, the HNE-induced oligomers are capable of seeding the amyloidogenesis of monomeric α-synuclein under in vitro conditions. When neuronal cells were treated with HNE, both the translocation of α-synuclein into vesicles and the release of this protein from cells were increased. Neuronal cells can internalize HNE-modified α-synuclein oligomers, and HNE treatment increased the cell-to-cell transfer of α-synuclein proteins. Innovation and Conclusion: These results indicate that HNE induces the oligomerization of α-synuclein through covalent modification and promotes the cell-to-cell transfer of seeding-capable oligomers, thereby contributing to both the initiation and spread of α-synuclein aggregates. Antioxid. Redox Signal. 18, 770–783.

RATIONALE Protein ubiquitination plays a critical role in regulating many cellular events, such as protein localization and stability, cellular signal transduction and DNA repair. Recent studies have shown that polyubiquitin (polyUb) chains elongate through heterogeneous isopeptide linkages to K11, K29, K48 and K63. In this study we have investigated the usage of isopeptide linkages of polyUb chains in different molecular weight regions by using quantitative mass spectrometry. METHODS Recombinant Chfr protein was autoubiquitinated by E1 enzyme, E2 enzyme UbcH5 and ubiquitin (WT Ub, K11R Ub, K48R Ub and K63R Ub) in vitro, and different molecular weight regions of ubiquitinated Chfr were then subjected to liquid chromatography coupled with tandem mass spectrometry (LC/MS/MS) following sodium dodecyl sulfate/polyacrylamide gel electrophoresis (SDS-PAGE) and in-gel digestion. RESULTS Absolute QUantitative Analysis (AQUA) of polyUb chain formation with wild-type (WT) and point mutants of ubiquitin was performed, and the results suggested that the K11 polyUb chain was most frequently used in the high ubiquitin conjugates of WT Ub. Furthermore, the extent of polyUb chain formation with K11R Ub was decreased about 10-fold compared to polyUb chain formation with WT Ub through the entire molecular weight region. The present study suggests that the linkage through K11 plays crucial roles in polyUb chain formation. CONCLUSIONS Topologies of polyUb chains in the low and high Ub conjugates were studied using mass spectrometry. K48 and K63 were the primary ubiquitination sites of the low molecular weight Ub conjugates, whereas K11 was the critical site of polyUb chain formation in high molecular weight Ub conjugates. Copyright © 2012 John Wiley & Sons, Ltd.

This paper presents an integrated circuit oriented Chua’s chaotic system with voltage controllability. The proposed chaotic system consists of an OTA (Operational Transconductance Amplifier)-based ground inductor, two passive capacitors, a MOS (Metal-Oxide-Semiconductor)-based active resistor and an OTA-based Chua’s diode with negative nonlinearity. A SPICE (Simulation Program with Integrated Circuit Emphasis) circuit analysis using 0.5-µm CMOS (Complementary Metal-Oxide-Semiconductor) process parameters was performed for the chaotic dynamics, such as the time waveform and the attractor plot. We confirmed that the chaotic behaviors of the system could be controlled by using the gate voltage of the MOS-based active resistor. Also, various chaotic dynamics of the circuit were analyzed for various MOS sizes of the OTA in the Chua’s diode.

This paper proposes a fuzzy speed tracking controller and a fuzzy rotor angular acceleration observer for a surface-mounted permanent magnet synchronous motor (SPMSM) based on the Takagi-Sugeno (T-S) fuzzy model. The proposed observer-based controller is robust to load torque variations since it utilizes rotor angular acceleration information instead of the load torque value. Linear matrix inequality (LMI) sufficient conditions are given to compute the gain matrices of the speed tracking controller and the observer. In addition, it is mathematically verified that the proposed observer-based control system is asymptotically stable. Simulation and experimental results are presented to confirm that the proposed control algorithm assures a better transient behavior and less sensitivity under model parameter variations than the conventional PI control method.

This paper introduces two types of magnetization, and reports the effect of the magnetization direction on the iron loss in a brushless DC (BLDC) motor using a 2-D time-stepped voltage source finite-element method (FEM). The iron losses were found to consist of hysteresis and eddy current loss, which were calculated from the time variation of the magnetic field distribution. To confirm the analysis, a prototype BLDC motor was constructed with a sintered ferrite magnet. The analysis and experimental results suggest that the magnetization direction has a significant effect in terms of the iron loss characteristics of the BLDC motor.

In this paper, an analysis of the complementary CMOS active pixel and readout circuit is carried out. Complementary pixel structure which is different from conventional 3TR APS structure consists of photo diode, reset PMOS, several NMOSs and PMOSs sets for complementary signals. Proposed CMOS image sensors pixel has been fabricated using 0.5 standard CMOS process. Measured results show that the output signal range is from 0.8 V to 3.8 V. This output signal range increased 125 % compared to conventional 3TR pixel in the condition of 5 V power supply.

A new sustain driver with an energy recovery circuit for ac plasma display panels is proposed. The proposed driver uses not expensive clamping diodes but relatively cheap RC components in the Y and X main boards without degrading the performance. Consequently, it features fewer power devices and lower cost because of no clamping diodes. To demonstrate the validity of the proposed driver, various experimental results with a prototype 42-inch HD PDP module are presented.

A new low-temperature driving method of EEFLs (external electrode fluorescent lamps) inverter for LCD TV backlights is proposed. The proposed driving scheme achieves a zero current switching (ZCS) of lower switches and dramatically reduces the temperature of the transformer at which the power loss mainly occurs. Moreover, the capacitance of EEFLs is calculated by the QV Lissajous analysis method and then the optimal switching interval for a low heating loss of the transformer is determined. To investigate the feasibility of the proposed driving method, various experimental results using a prototype 17-inch LCD TV backlight with 12 EEFLs are presented.

Integrated circuit of a new neuron chain with a synapse function for Hodgkin-Huxley model which is a good electrical model about a real biological neuron is implemented in a 1 poly 2 metal CMOS technology. Pulse type neuron chain consist of series connected current controlled single neurons through synapses. For the realization of the single neuron, a pair of voltage mode oscillators using operational transconductance amplifiers and capacitors is used. The synapse block which is a connection element between neurons consist of a voltage-current conversion circuit using current mirror. SPICE simulation results of the proposed circuit show 160 mV amplitude pulse output and propagation of the signal through synapses. Measurements of the fabricated pulse type neuron chip in condition of power supply are shown and compared with the simulated results.

We propose a new image pixel architecture which has OFD(Over Flow Device) node by improving conventional 3TR pixel structure. Newly designed pixel consists of photo diode which is verified with HSPICE simulation, PMOS reset transistor, several NMOS and several PMOS transistors. Photodiode signals from each PMOS and NMOS are detected by Reset PMOS. These output signals give enough chances to detect wide operation coverage because OFD node has overflow photocurrent. According to various light intensity, we analyzed characteristic of the output voltage with a SPICE tool. Proposed pixel output has specific value which can detect possible from to light intensity. It has wide-dynamic range of 160 dB.

Three-dimensional IR emission characteristics of a weak discharge in the reset period were investigated with the specially fabricated 3-D test panel which has a glass prism instead of one flank of a closed wall in AC PDP. Based on the 3-D images of the IR emissions measured in the reset period, the IR emissions from the cathode electrodes were not observed all through the rising and falling ramp reset period. During the falling ramp reset period, the emissions from the X and Ay electrodes, which work as anodes, were seen. Moreover, it was observed that the address obviously discharge occurs between the Y and a part of address (Ax) electrode. These results were experimentally confirmed with the 6-in 3-D plasma display panel.

Three-dimensional infrared (IR) emissions in address period were experimentally investigated using a 6-in 3-D plasma display panel. Depending upon various driving conditions, two address discharge modes were observed: single-tail mode and double-tail mode (DTM). The DTM should be avoided because it may result in the discharge failure of the addressed cells. Based on the 3-D images of the IR emissions in the address period, the wall charge distributions on the Y and A electrodes after two address discharge modes were estimated. In addition, the minimum sustain and address voltages (Vs and Va) were measured to compare the voltage margins between the two modes.

A novel sustain driver with energy recovery circuit is proposed based on low-cost and low-rating devices for plasma display panels. Since the proposed driver is designed by devices with half of voltage rating compared with the conventional Weber-type driver, it can take advantages of semiconductor devices with reduced conduction and switching losses as well as cheaper costs. Moreover, the proposed driver is supplied from half of required sustain voltage level in comparison with the conventional driver. The developed structure is configured with fewer devices than the prior approach with a cascaded Weber-type driver, which employs reduced voltage-rating components. As a result, the PDP driver presented in this paper can feature smaller size, lower cost, and high efficiency for both the sustain driver and the power supply circuit.

A new simple-structure PDP driving circuit without using any path separation switch is proposed and its operational principle is addressed in detail. The proposed driver employs not a path switch but a path diode to prevent the shoot-through current which flows from Y-main ground to negative scan low voltage source during the ramp-down reset and address periods. Consequently, it has advantages such as simpler structure, higher efficiency, and lower cost due to no path switches. To verify the effectiveness of the proposed driver, experimental results using a prototype 42-inch HD PDP module are presented.

In this paper, a circuit analysis of the complementary CMOS active pixel and readout circuit is carried out. Complementary pixel structure which is different from conventional 3TR APS structure is consist of photo diode, reset PMOS, several NMOSs and PMOSs sets for complementary signals. Photo diode is modelled with Medici device program. HSPICE was used to analyze the variation of the signal feature depending on light intensity using standard CMOS process. Simulation results show that the output signal range is from 0.8 V to 4.5 V. This signal range increased 135 % output dynamic range compared to conventional 3TR pixel in the condition of 5 V power supply.

A new pulse-scan-based driving method that can significantly reduce total address time delay of discharge ignition during the address period in a plasma display panel (PDP) is proposed. By applying lower negative scan-pulse voltage to the Y electrode for a short interval, the proposed scheme accelerates the ignition of the gas discharge between addressing electrode (A) and scanning electrode (Y), and then, it reduces the ignition time delay which is closely related to the addressing time. Consequently, the high-speed addressing method can be achieved by it because the width of each scan pulse or each address pulse can be reduced. Therefore, this earned addressing time can directly contribute to the implementation of a single-scan (SS) driving scheme or the improvements in brightness with more sustain pulses. Experimental results with a prototype 50-in full-high-definition SS PDP module show that the total address time delay (Td = Tf +Ts) of discharge ignition with the proposed pulse-scan driving method is reduced by about 10% compared with the conventional driving method.

A control technique is developed for a three-phase four-wire split DC bus inverter of a single distributed generation unit working in island mode. The control technique combines an inner discrete-time sliding mode controlled (DSMC) current loop and an outer robust servomechanism controlled voltage loop. The control algorithms are developed under stationary alphabeta0 (Clarke's) reference frame and a modified space vector pulsewidth modulation (MSVPWM) is proposed to implement the algorithm under Clarke's reference frame. The proposed technique achieves voltage regulation with low steady state error and low total harmonic distortion and fast transient response under various load disturbances. Meanwhile the usage of MSVPWM in a stationary alphabeta0 reference frame yields better transient performance under limited DC bus voltage compared to conventional uniformly sampled sine wave modulation in ABC reference frame. In this paper, besides the development and description of the algorithms, a series of discussions, analysis and studies are performed on the proposed control technique, including the L-C filter design issue, frequency domain closed-current-loop and closed-voltage-loop responses, and time domain simulations and experiments under various load conditions. All the analysis, simulations, and experiments demonstrate the effectiveness of the proposed control solution.

The problem to localize transparent glass obstacles using laser range finder is very difficult and still open problem. Most of applications use additional sensor device such as sonar sensor to cope with the transparent glass obstacle environment. This paper deals with that problem only using laser range finder. By the insight from human sensing mechanism which uses the fusion of more data with different view directions or different measurement locations, a novel method to localize transparent glass obstacles is addressed. And, the effectiveness of the proposed algorithm is evaluated by the real robot experiments with three case studies.

In this paper, we propose a new complementary image sensor pixel structure by improving the conventional 3TR pixel structure. Proposed complementary pixel structure for wide dynamic range CIS consists of photo diode, PMOS reset transistor, several PMOS and NMOS transistors for complementary signals. We show SPICE simulation results of the complementary image pixel structure for optimization. Proposed complementary pixel was fabricated with 0.5 µm 1-poly 2-metal standard CMOS process. From the measured results, output voltage of the proposed pixel is 0.8 V to 3.8 V in condition of the 5 V power supply. These output signals give enough chances to detect wide operation coverage.

The total energy consumed by the radios is compared for a cooperative transmission (CT) protocol and a non-CT routing protocol, in a two-hop, single cluster, ad hoc network. The radio energy model is a function of parameter sets that are typically found in radio specifications. The protocols are compared for five different parameter sets, corresponding to five different existing radios. The CT protocol is the Opportunistic Large Array (OLA). The non-CT protocol simply selects one node from the cluster to forward the packet, but other nodes in the cluster that do not relay are assumed to overhear or decode at least part of the packets. The relative energy consumption is determined as a function of the fraction of the data packet that is decoded by the node for decision-making. CT is shown to be beneficial for certain decoding fractions and for certain radio parameter sets.

A simplified driver based on low-cost and low-rating devices is presented for plasma display panels (PDPs). Since the proposed driver has been designed by devices with half of voltage rating compared with the conventional Weber-type driver, it can take advantages of semiconductor devices with reduced conduction and switching losses as well as cheaper costs. In addition, a simpler structure of the proposed circuit with fewer devices can eliminate drawback of the prior approach with a series-connected Weber-type driver, which utilizes reduced voltage rating components. Moreover, the proposed driver is supplied from half of required sustain voltage level. The reduced supply voltage of the driver results in cost reduction and improved efficiency in the power supply blocks. Thus, the PDP driver presented in this paper can feature smaller size, lower cost, and high efficiency for both the sustain driver and the power supply circuit.

This paper describes characteristics of the handset with transmit and receive diversity. A 2nd antenna was added to the existing commercial handset. QUALCOMM's MSM6500 chip was used for receive diversity, and the DiversityPlus/sub /spl trade// technique of Magnolia Broadband, Inc., was used for transmit diversity. The test result of receive diversity was 4.1 dB SINR gain and 35% forward link traffic throughput gain. In the case of transmit diversity, there was 3.7-4.8 dB transmit power gain and 19% reverse link traffic throughput gain.

In this paper, we propose an Advanced Soft Remote Control System so as to endow the users with the ability to control various home appliances instead of individual remote controller for each appliance and to command naturally at various places without being conscious of the view direction of the cameras. Through the developed system, the user first selects the device that he/her wants to control by pointing it with his/her hand. Then, the user can command operation of the desired functions via 10 predefined basic hand motion commands. By the experiment, we can get 97.1% recognition rate during offline test and 96.5% recognition rate during online test. The developed system complements some inconveniences of conventional remote controllers specially by giving additional freedom to persons with movement deficits and people without disabilities.

Distributed generation units with small energy sources, such as fuel cells, micro-turbines, and photovoltaic devices, can be connected to utility grid as alternative energy sources besides providing power to their local loads. The distributed generation units are interfaced with utility grid using three phase inverters. With inverter control, both active and reactive power pumped into the utility grid from the distributed generation units can be controlled. Reactive power flow control allows the distributed generation units to be used as static VAr compensation units besides energy sources. This work presents a distributed generation unit control technique which provides robust voltage regulation with harmonic elimination under island running mode and decoupled active and reactive power flow control under grid-connected mode. The control technique, which combines discrete-time sliding mode current control, robust servomechanism voltage control, and integral power control, enables seamless switching between island mode and grid-connected mode and guarantees sinusoidal line current waveform such nonlinear local load. The P Q coupling issue is addressed and the stability of the power control loop is proved using Lyapunov direct method.

In this paper, we describe the "soft remote control system" that provides easy control of home installed appliances to improve the inhabitant's comfort. This system is feasible to control various home appliances naturally by recognizing the user's hand gestures in the "intelligent sweet home". The user selects the device that he/her wants to control by pointing it with his/her hand. Then, the user can command operation of the desired function via a predefined hand gesture. The approach complements the inconvenience of the conventional remote controllers giving additional freedom to persons with movement deficits and people without disabilities.