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Oscillatory systems with time delays exist widely in actual industrial process. This paper discusses the design and tuning of linear active disturbance rejection controller (LADRC) for the oscillatory systems with large time delays. First, internal model controllers (IMC) are designed for the oscillatory systems to compensate the time-delay and cancel the complex poles; then they are implemented with the general LADRC structures and approximated with observer-bandwidth-based LADRCs. Afterwards, the third-order LADRC tuning formulas for oscillatory systems are derived from the IMC controllers. Simulation examples and load frequency control(LFC) in power system with communication delay are used to test the applicability of the proposed tuning formula.

In a proton therapy system based on cyclotrons, a kicker magnet is an essential equipment to perform fast beam switch within 100 μ s level during energy modulation and spot scanning procedures. This paper gives a systematic view related to the design and technical considerations of a fast kicker applied to HUST-PTF. From the layout and physical requirement of the kicker, a comparative study on the static/dynamic magnetic field with two type of core materials is performed, and a MnZn ferrite core is chosen finally. Technical considerations including the structure design, the topology design of the power supply, and the method for dynamic field measurement are introduced as well.

Background Hepatocellular carcinoma (HCC) is a common tumor malignancy threatening a significant number of people worldwide. Although microRNAs (miRNAs) have been shown to play essential role in tumorigenesis, little is known about their role in T cells functions during HCC progression. Methods The abundances of miR-26b-5p were detected in HCC tissues or cells, T cells and H22 cells by quantitative real-time polymerase chain reaction (qRT-PCR). Regulation effect of miR-26b-5p on proviral integrations of moloney virus 2 (PIM2) was investigated by qRT-PCR, western blot (WB) and immunohistochemical analysis. The effect of miR-26b-5p and PIM-2 on cytokines secretion in CD4+ and CD8+ cells was evaluated by commercial enzyme linked immunosorbent assays (ELISA) kit. The interaction between miR-26b-5p and PIM-2 was probed by luciferase activity and RNA immunoprecipitation (RIP). H22 subcutaneous model was established to investigate the interaction of miR-26b-5p with HCC and immune competence. Results The abundance of miR-26b-5p was decreased in HCC and associated with poor survival. Addition of miR-26b-5p contributed to secretion of tumor necrosis factor α (TNF-α), interferon-γ (IFN-γ), interleukin-6 (IL-6) and IL-2 in CD4+ and CD8+ cells. Interestingly, PIM-2 was negatively regulated by miR-26b-5p and PIM-2 knockdown reversed anti-miR-26b-5p-mediated immunosuppression. Moreover, inhibitory effect of miR-26b-5p on HCC tumorigenesis was dependent on immune competence. Conclusions miR-26b-5p enhanced T cells responses by targeting PIM-2 in HCC, uncovering a promising therapeutic opportunity of HCC through reactivating immune system.

This paper compares Active Disturbance Rejection Control (ADRC), Proportional–Integral (PI) and ultra-local adaptive controller (also labeled intelligent-PID) when applied to Automatic Generation Control (AGC) for a multi-area power system with co-simulation of the communication system. The co-simulation platform PiccSIM integrates Simulink/Matlab and Network Simulator Ver. 2 (NS2) with real-time simulation data exchanged through Local Area Network (LAN). Instead of the traditional control center, automatic generation controller is embedded in each participating generation unit locally to avoid communication delay for the control signals. This new control scheme is referred to as fully distributed AGC. The performance of the proposed scheme is tested on a nonlinear model of New England (NE) 39-bus system with the co-simulated tie-line power flow communication delays. The simulation results present very promising performance and good robustness of ADRC in the presence of communication delays, suggesting that the stability of the overall cyber–physical system is enhanced significantly.

Pancreatic cancer (PC), which has a high fatality rate, is a kind of cancer with poor diagnosis and poor prognosis. Development of selective and sensitive detection platform to diagnose and prognostic of PC has attracted considerable attention. The miRNA-198 has been reported a potential prognostic and early diagnostic marker signature of PC. Herein, we report a novel sensitive detection of miRNA-198 in buffer and serum based on one dimensional chitosan/fluorescein isothiocyanate (CS/FITC) fluorescent microfiber waveguide system combined with the catalytic hairpin assembly amplification strategy. By combination with condensing enrichment effect, the proposed detection platform exhibited high specificity and sensitivity to miRNA-198 target, giving a detection limit as low as 2 fM. More importantly, the proposed detection platform can be applied directly to distinguish the expression of miRNA-198 in clinical serum, affording the ability to distinguish pancreatic cancer patients from those of healthy human beings, and quantify the expression variation of miRNA-198 for the pancreatic cancer patients before and after resection, which may pave the way to develop novel clinical diagnostic equipment for cancer diagnosis and therapeutic evaluation.

Purpose: A systematic design procedure for a superconducting gantry is presented. To increase the momentum acceptance of the gantry beamline, alternating-gradient combined-function magnets were used to suppress dispersion. Methods: The main difficulties and challenges occurring in the design procedure, such as the difference between low- and high-order optics and the difference in beam behavior between simplified optics models and realistic magnetic fields, were analyzed. On the basic of these analyses, a step-by-step iterative design approach was proposed. In these steps, a genetic algorithm (GA) was used for multi-objective optimization, and graphics processing unit (GPU) acceleration was adopted for realistic model simulation. Results: The results of the design demonstrated that momentum acceptance of − 7 % ∼ 5 % was achieved for particle tracking in realistic magnetic fields. Conclusions: Using a GA, multi-objective optics fitting up to the fifth order became feasible. The optimization procedure was also more intelligent compared with the traditional one, which depends on experience and manual intervention. The use of GPU acceleration in magnetic field calculation and particle tracking dramatically reduced the overall optimization time. Finally, design optimization for a large momentum acceptance gantry beamline with realistic magnetic fields was achieved.

Here we report on a modulated sub-nanosecond lidar-radar for underwater target detection. The modulated laser source is consisted of a 1064 nm master oscillator power amplifier (MOPA) and a frequency-doubling module, outputting pulse energy of 178.1 mJ at 1064 nm with 0.76 ns pulse duration and 87.6 mJ at 532 nm. By using a Fabry–Perot cavity containing a KTP crystal and two reflectors, the 532 nm laser pulse is modulated into the burst mode with a repetition rate of 500 MHz. A streak tube camera is used as the signal receiving apparatus. An underwater target detection experiment has been carried out. The results indicate that this lidar-radar could emit a stable and powerful modulated signal, which greatly increases the underwater detection range. The cooperation of the streak tube imaging and modulated laser source for underwater target detection experiments is the first attempt in this field. The clear 3-D and 4-D images of the target underwater across 20 m are obtained in the experiments and the spatial resolution of 9 mm can be achieved.

A proton therapy facility based on spot scanning technique requires a fast ON/OFF beam switch during beam spots and energy modulation procedures. At HUST, a proton therapy facility (HUST-PTF) with multiple treatment rooms is under development. For HUST-PTF, this beam switch function is implemented by a fast kicker magnet and downstream beam dump. This paper introduces the development and measurement of this kicker magnet system, with main topics: (1) the development and measurement of the fast kicker magnet; (2) the corresponding pulsed power supply to implement the kicker function; (3) the dynamic magnetic field measurement system based on printed circuit board (PCB) technique.

A polarization-independent 4 × 4 optical matrix switch based on a 580-nm-thick silicon nitride platform is designed and experimentally demonstrated. The switch is composed of four 2 × 2 Mach-Zehnder interferometers, with each integrated with a pair of Ti/Pt resistive micro-heaters. Polarization-independent performance can be realized with the power consumption for a single switching operation of less than 130 mW. The measured rise/fall time of the switch upon electrical tuning is about 24.5/30.5 μs, corresponding to a maximum switching speed of about 20 kHz. The insertion loss is about 7.2 dB for transverse electric light or 5.7 dB for transverse magnetic wave, with a polarization dependent loss of about 0.65 dB. The device performance can be further optimized and even large-scale silicon nitride polarization-insensitive electro-optical matrix switches can be expected for future optical communication applications.

Lithium iron phosphate/carbon (LiFePO 4 /C) microspheres with an excellent multiple conductive network are synthesized using iron (III) acrylate as both iron and carbon sources. The innermost network is constructed by a uniform carbon layer on the surface of LiFePO 4 primary nanoparticles, which derives from the carbonation of in-situ polymerized polyacrylic acid (PAA) layer. Moreover, the acetylene black added in spay drying process fills the voids among primary nanoparticles to construct the second conductive network. Finally, the carbon from optimized content sucrose used as binder and linker can interconnect primary nanoparticles together to form the third network. In addition, subtle mesoporous structure is formed inside the multiple carbon conductive network. The highly speed electron transfer and lithium ion transportation can be achieved simultaneously for LiFePO 4 /C microspheres. All these features contribute to their great rate performance (163.1 mAh g −1 at 0.1 C and 126.5 mAh g −1 at 5 C) and outstanding cycling stability (95.3% of capacity retention after 1000 cycles at 5 C/5C). The well-designed LiFePO 4 /C microspheres with unique structure are very promising cathode materials for rechargeable lithium ion power batteries.

A pulse master-oscillator fiber power amplifier system with china-made large-mode-area fiber and a (6+1)×1 multimode combiner is demonstrated. The system generates up to 4.8 W of amplified radiation (100 kHz) at a wavelength of 1064 nm with a near-diffraction-limited beam quality (M2=1.2), and the overall slope efficiency with respect to the launched pump power is 50%. Some basic characteristics of this system, including the pulse-amplification characteristics, the gain characteristics, as well as the emission spectrum characteristics are investigated in detail.

The pulse-shaping technique has found widespread applications in nonlinear optics and material processing. Experimental research on laser-induced plasma shutter to control the 532 nm pulse width is conducted. The impacts of the total pulse output energy on pulse compression are investigated, and a useful conclusion can be drawn that there exists an optimal value of pulse energy at which the shortest output pulse of 3.23 ns can be obtained without a device for delay-time. Once the device for delay-time is employed to change the optical differences between two laser paths, the pulse width can be further shortened to 1.51 ns. In short, the 1.5-12 ns width-tunable 532 nm laser pulses have been obtained by adopting the laser-induced plasma shutter technique. (C) 2007 Elsevier GmbH. All rights reserved.

A 2,3,6,7-tetrabromonaphthalene diimide (2) was readily synthesized in high yield from 2,3,6,7-tetrabromonaphthalene dianhydride by an improved dehydrohalogenation-based imidization reaction. The further nucleophilic aromatic substitution (SNAr) reaction