Condition Optimization of Lipopeptide Production by Bacillus natto NT-6 in Solid-State Fermentation with Box-Behnken Design

Solid-state fermentation has certain advantages in improving the yield of lipopetide, Box-Behnken Design（BBD） was adopted to optimize the producing condition of the antibacterial lipopetide produced by Bacillus natto in this article. The optimal solid state fermentation conditions were obtained： 10 g solid medium（7 g of wheat bran, 3 g of soybean meal） with appropriate inorganic salt（glucose 0.67%,sodium glutamate 0.64%,（NH4）2SO40.15%, K2HPO40.10%）; moisture content 123.78%; inoculation amount 10%; cultivation temperature 36.75 ℃ and cultivation time 72.4 h. The maximum production of lipopetide is 61.76 mg/gds under such conditions. This is the first report on the optimization of lipopeptide fermentation conditions in solid-state fermentation by wheat bran and soybean meal with Bacillus natto NT-6 strain, and will contribute to the development of lipopetide production.

Resistive switching behavior and mechanism of HfO_(x) films with large on/off ratio by structure design

Different bilayer structures of HfO_(x)/Ti(TiO_(x)) are designed for hafnium-based memory to investigate the switching characteristics. The chemical states in the films and near the interface are characterized by x-ray photoelectron spectroscopy,and the oxygen vacancies are analyzed. Highly improved on/off ratio(~104) and much uniform switching parameters are observed for bilayer structures compared to single layer HfO_(x) sample, which can be attributed to the modulation of oxygen vacancies at the interface and better control of the growth of filaments. Furthermore, the reliability of the prepared samples is investigated. The carrier conduction behaviors of HfO_(x)-based samples can be attributed to the trapping and de-trapping process of oxygen vacancies and a filamentary model is proposed. In addition, the rupture of filaments during the reset process for the bilayer structures occur at the weak points near the interface by the recovery of oxygen vacancies accompanied by the variation of barrier height. The re-formation of fixed filaments due to the residual filaments as lightning rods results in the better switching performance of the bilayer structure.

Electromagnetic Design of a Switched Reluctance Motor With Segmental Rotors and Full-pitch Windings

整距绕组分块转子开关磁阻电机具有高速运行时低风（油）阻和低铁心损耗等优点，特别适合用于航天航空驱动系统。根据整距绕组分块转子开关磁阻电机的基本工作原理，结合输出功率与平均转矩的关系，将绕组电流等效为方波，推导出了整距绕组分块转子开关磁阻电机的主体尺寸计算公式；基于电机定转子未对齐位置和对齐位置的电磁特性，以及整距绕组分块转子开关磁阻电机的电磁特点，确定了定、转子极弧系数选取的规则；同时分析了绕组匝数等主要尺寸的选取的规则；最后，基于上述方法优化设计了一台实验样机，并通过有限元仿真及实验验证了整距绕组分块转子开关磁阻电机的电磁设计方法的正确性。

Asynchronous Observer Design for Switched Linear Systems: A Tube-Based Approach

This paper proposes a tube-based method for the asynchronous observation problem of discrete-time switched linear systems in the presence of amplitude-bounded disturbances.Sufficient stability conditions of the nominal observer error system under mode-dependent persistent dwell-time(MPDT)switching are first established. Taking the disturbances into account, a novel asynchronous MPDT robust positive invariant(RPI) set and an asynchronous MPDT generalized RPI(GRPI)set are determined for the difference system between the nominal and disturbed observer error systems. Further, the global uniform asymptotical stability of the observer error system is established in the sense of converging to the asynchronous MPDT GRPI set, i.e., the cross section of the tube of the observer error system. Finally, the proposed results are validated on a space robot manipulator example.

Review of Linear Switched Reluctance Motor Designs for Linear Propulsion Applications

Linear switched reluctance motor(LSRM)and its applications in different industries have been an interesting research topic for the past few years.LSRMs have proved to be a suitable alternative in a variety of applications requiring linear motion.However,its use is not that popular which instigated an active interest in the evolution of newer LSRM configurations.Enhancement in its propulsion force along with the reduction in force ripples,weight,acoustic noise,and vibration have been the main objectives in recently proposed LSRM designs.In this paper,recently proposed LSRM designs are reviewed and analyzed.The paper presents a one-stop introduction and a complete update to the designs,both in terms of qualitative and quantitative parameters.In addition,it takes into account the challenges in the implementation of these designs.Based on a detailed comparison of these designs as presented in this paper,an appropriate design can be chosen for a given application.

Multimode Design and Analysis of an Integrated Leg-Arm Quadruped Robot with Deployable Characteristics

To improve locomotion and operation integration, this paper presents an integrated leg-arm quadruped robot(ILQR) that has a reconfigurable joint. First, the reconfigurable joint is designed and assembled at the end of the legarm chain. When the robot performs a task, reconfigurable configuration and mode switching can be achieved using this joint. In contrast from traditional quadruped robots, this robot can stack in a designated area to optimize the occupied volume in a nonworking state. Kinematics modeling and dynamics modeling are established to evaluate the mechanical properties for multiple modes. All working modes of the robot are classified, which can be defined as deployable mode, locomotion mode and operation mode. Based on the stability margin and mechanical modeling, switching analysis and evaluation between each mode is carried out. Finally, the prototype experimental results verify the function realization and switching stability of multimode and provide a design method to integrate and perform multimode for quadruped robots with deployable characteristics.

Optimal Designs of Wound Field Switched Flux Machines with Different DC Windings Configurations

Wound field switched flux(WFSF)machines exhibits characteristics of the simple robust rotor,flexible flux-adjustable capability,and no risk of demagnetization.However,they suffer from a poor torque density compared with permanent magnet machines due to the saturation.Therefore,in this paper,two WFSF machines with single-and double-layer DC windings,respectively,are optimized for the maximum torque.The end-winding(EW)lengths differ in these two machines,which can affect the optimal design.Design parameters including the DC to armature winding copper loss ratio,slot area ratio and split ratio are optimized when two machines have the same copper loss and overall sizes.In addition,the influence of the flux density ratio,total copper loss,air-gap length and aspect ratio on the optimal split ratio is investigated using the finite element method and results are explained through the analytical model accounting for the saturation.It is discovered that the EWs have no effect on the optimal copper loss ratio,which is unity.In terms of the slot area ratio,the machine with single-layer DC windings prefers smaller DC slot areas than armature slot areas.In the WFSF machine with longer EWs,the optimal split ratio becomes smaller.Moreover,compared with other parameters,the flux density ratio can significantly affect the optimal split ratio.

SWITCHED-CURRENT FILTER DESIGN USING CASCADED SECTIONS

A new analogue sampled-data active device, named as a switched-current operationalamplifier (SIOA), is presented. The use of active circuit elements may simplify drawing the circuitdiagram significantly greatly and may permit easier analysis and synthesis of SI networks. Anumber of all pole and elliptic (second-or third-order) switched-current (SI) filters are derivedfrom the switched capacitor prototypes. These can be used as simple self-contained filters or asfilter sections in the cascaded realizations of a higher order transfer functions. To illustrate theapproach, a fifth-order low-pass filter is designed.

Performance Evaluation and Comparison of Multi - Objective Optimization Algorithms for the Analytical Design of Switched Reluctance Machines

This paper systematically evaluates and compares three well-engineered and popular multi-objective optimization algorithms for the design of switched reluctance machines.The multi-physics and multi-objective nature of electric machine design problems are discussed,followed by benchmark studies comparing generic algorithms(GA),differential evolution(DE)algorithms and particle swarm optimizations(PSO)on a 6/4 switched reluctance machine design with seven independent variables and a strong nonlinear multi-objective Pareto front.To better quantify the quality of the Pareto fronts,five primary quality indicators are employed to serve as the algorithm testing metrics.The results show that the three algorithms have similar performances when the optimization employs only a small number of candidate designs or ultimately,a significant amount of candidate designs.However,DE tends to perform better in terms of convergence speed and the quality of Pareto front when a relatively modest amount of candidates are considered.

High performance integrated photonic circuit based on inverse design method

The basic indexes of all-optical integrated photonic circuits include high-density integration,ultrafast response and ultralow energy consumption.Traditional methods mainly adopt conventional micro/nano-structures.The overall size of the circuit is large,usually reaches hundreds of microns.Besides,it is difficult to balance the ultrafast response and ultra-low energy consumption problem,and the crosstalk between two traditional devices is difficult to overcome.Here,we propose and experimentally demonstrate an approach based on inverse design method to realize a high-density,ultrafast and ultra-low energy consumption integrated photonic circuit with two all-optical switches controlling the input states of an all-optical XOR logic gate.The feature size of the whole circuit is only 2.5μm×7μm,and that of a single device is 2μm×2μm.The distance between two adjacent devices is as small as 1.5μm,within wavelength magnitude scale.Theoretical response time of the circuit is 150 fs,and the threshold energy is within 10 fJ/bit.We have also considered the crosstalk problem.The circuit also realizes a function of identifying two-digit logic signal results.Our work provides a new idea for the design of ultrafast,ultra-low energy consumption all-optical devices and the implementation of high-density photonic integrated circuits.

Computer Modeling and Simulation Evaluation of High Power LED Sources for Secondary Optical Design

Proposed and demonstrated is a novel computer modeling method for high power light emitting diodes(LEDs). It contains geometrical structure and optical property of high power LED as well as LED dies definition with its spatial and angular distribution. Merits and non-merits of traditional modeling methods when applied to high power LEDs based on secondary optical design are discussed. Two commercial high power LEDs are simulated using the proposed computer modeling method. Correlation coefficient is proposed to compare and analyze the simulation results and manufacturing specifications. The source model is precisely demonstrated by obtaining above 99% in correlation coefficient with different surface incident angle intervals.

A vector inserting TPG for BIST design with low peak power consumption

A test pattern generator （TPG） which can highly reduce the peak power consumption during built-in self-test （BIST） application is proposed. The proposed TPG, called LPpe-TPG, consists of a linear feedback shift register （LFSR） and some control circuits. A procedure is presented firstly to make compare vectors between pseudorandom test patterns by adding some circuits to the original LFSR and secondly to insert some vectors between two successive pseudorandom test patterns according to the ordinal selection of every two bits of the compare vector. Then the changes between any successive test patterns of the test set generated by the LPpe-TPG are not more than twice. This leads to a decrease of the weighted switching activity （WSA） of the circuit under test （CUT） and therefore a reduction of the power consumption. Experimental results based on some ISCAS＇ 85 benchmark circuits show that the peak power consumption has been reduced by 25.25% to 64.46%. Also, the effectiveness of our approach to reduce the total and average power consumption is kept, without losing stuck-at fault coverage.

SMPS Design Toolkit 1.6设计软件及其应用

美国飞兆半导体公司(Fairchild Semiconduetor Inc.)最近推出新的开关电源设计软件SMPS Design Toolkit 1.6,该软件具有制作精良、功能强大、设计灵活、使用简便等显著优点。用户利用交互式设计助手,根据程序提供的步骤,很容易完成反激式开关电源或准谐振式变换器的全部设计工作。

Ultra-Low Power Designing for CMOS Sequential Circuits

Power consumption is the bottleneck of system performance. Power reduction has become an important issue in digital circuit design, especially for high performance portable devices (such as cell phones, PDAs, etc.). Many power reduction techniques have also been proposed from the system level down to the circuit level. High-speed computation has thus become the expected norm from the average user, instead of being the province of the few with access to a powerful mainframe. Power must be added to the portable unit, even when power is available in non-portable applications, the issue of low-power design is becoming critical. Thus, it is evident that methodologies for the design of high-throughput, low-power digital systems are needed. Techniques for low-power operation are shown in this paper, which use the lowest possible supply voltage coupled with architectural, logic style, circuit, and technology optimizations. The threshold vol-tages of the MTCMOS devices for both low and high Vth are constructed as the low threshold Vth is approximately 150 - 200 mv whereas the high threshold Vth is managed by varying the thickness of the oxide Tox. Hence we are using different threshold voltages with minimum voltages and hence considered this project as ultra-low power designing.

Progress and perspective of the cathode/electrolyte interface construction in all-solid-state lithium batteries

Security risks of flammability and explosion represent major problems with the use of conventional lithium rechargeable batteries using a liquid electrolyte.The application of solid-state electrolytes could effectively help to avoid these safety concerns.However,integrating the solid-state electrolytes into the all-solid-state lithium batteries is still a huge challenge mainly due to the high interfacial resistance present in the entire battery,especially at the interface between the cathode and the solid-state electrolyte pellet and the interfaces inside the cathode.Herein,recent progress made from investigations of cathode/solid-state electrolyte interfacial behaviors including the contact problem,the interlayer diffusion issue,the space-charge layer effect,and electrochemical compatibility is presented according to the classification of oxide-,sulfide-,and polymer-based solid-state electrolytes.We also propose strategies for the construction of ideal next-generation cathode/solid-state electrolyte interfaces with high room-temperature ionic conductivity,stable interfacial contact during long cycling,free formation of the space-charge region,and good compatibility with high-voltage cathodes.

Quasi-Solid-State Ion-Conducting Arrays Composite Electrolytes with Fast Ion Transport Vertical-Aligned Interfaces for All-Weather Practical Lithium-Metal Batteries

The rapid improvement in the gel polymer electrolytes(GPEs)with high ionic conductivity brought it closer to practical applications in solid-state Li-metal batteries.The combination of solvent and polymer enables quasi-liquid fast ion transport in the GPEs.However,different ion transport capacity between solvent and polymer will cause local nonuniform Li+distribution,leading to severe dendrite growth.In addition,the poor thermal stability of the solvent also limits the operating-temperature window of the electrolytes.Optimizing the ion transport environment and enhancing the thermal stability are two major challenges that hinder the application of GPEs.Here,a strategy by introducing ion-conducting arrays(ICA)is created by vertical-aligned montmorillonite into GPE.Rapid ion transport on the ICA was demonstrated by 6Li solid-state nuclear magnetic resonance and synchrotron X-ray diffraction,combined with computer simulations to visualize the transport process.Compared with conventional randomly dispersed fillers,ICA provides continuous interfaces to regulate the ion transport environment and enhances the tolerance of GPEs to extreme temperatures.Therefore,GPE/ICA exhibits high room-temperature ionic conductivity(1.08 mS cm^(−1))and long-term stable Li deposition/stripping cycles(>1000 h).As a final proof,Li||GPE/ICA||LiFePO_(4) cells exhibit excellent cycle performance at wide temperature range(from 0 to 60°C),which shows a promising path toward all-weather practical solid-state batteries.

A Tri-Salt Composite Electrolyte with Temperature Switch Function for Intelligently Temperature-Controlled Lithium Batteries

The intense research of lithium-ion batteries has been motivated by their successful applications in mobile devices and electronic vehicles.The emerging of intelligent control in kinds of devices brings new requirements for battery systems.The high-energy lithium batteries are expected to respond or react under different environmental conditions.In this work,a tri-salt composite electrolyte is designed with a temperature switch function for intelligently temperature-controlled lithium batteries.Specifically,the halide Li_(3)YBr_(6)together with LiTFSI and LiNO_(3)works as active fillers in a low-melting-point polymer matrix(polyethyleneglycol dimethyl ether(PEGDME)and polyethylene oxide(PEO)),which is further filled into the pre-lithiated alumina fiber skeleton.Above 60°C,the composite electrolyte exists in the liquid state and fully contacts with the working electrodes on the liquid–solid interface,effectively minimizing the interfacial resistance and leading to high discharge capacity in the cell.The electrolyte is changed into a solid state below 30°C so that the ionic conductivity is significantly reduced and the interface resistance is increased dramatically on the solid–solid interface.Therefore,by simply adjusting the temperature,the cell can be turned“ON”or“OFF”intentionally.This novel function of the composite electrolyte has enlightening significance in developing intelligently temperature-controlled lithium batteries.

Design and Analysis of a Novel Rotor-Segmented Axial-Field Switched Reluctance Machine

As excitation strategy is influenced by the parity of phase number,and serious end effect is caused by full pitch windings adopted by the conventional rotor-segmented switched reluctance machine(RS-SRM),a novel rotor-segmented axial-field switched reluctance machine(RS-AFSRM),which adopts concentrated windings,is proposed in this paper,whose control strategy is independent of the parity of phase number.The stator of the proposed RS-AFSRM consists of inner and outer flux-conductive ring,excitation poles,and stator yoke,while the rotor consists of fan-shape cylinder-type segments.The structure and principle of the proposed machine is introduced through the magnetic circuit model of the machine.The fringing effect on air-gap field is considered.The simplified magnetic circuit considering the fringing effect is presented and the fringing effect coefficient is introduced.The design procedure considering the fringing effect through iterative modification is presented in this paper and is validated through 3D finite-element method(3D-FEM).Results show that both magnetic field distribution and operation are reasonable and satisfy the requirements.

Design of Non-contact On-load Automatic Regulating Voltage Transformer

At present, an automatic-mechanic contact tap-changer is widely used in power system, but it can not frequently operate. In addition, arc will occur when the switch changes. In order to solve these two problems, this paper presented an automatic on-load voltage-regulating distributing transformer which employed non-contact solid-state relay as tap-changer, and mainly introduced its structure, basic principal, design method of each key link and experimental results. Laboratory simulation experiments informed that the scheme was feasible. It was a smooth and effective experiment device, which was practical in application.

End-to-end computational approach to the design of RNA biosensors for detecting miRNA biomarkers of cervical cancer

Cervical cancer is a global public health subject as it affects women in the reproductive ages,and accounts for the second largest burden among cancer patients worldwide with an unforgiving 50%mortality rate.Relatively scant awareness and limited access to effective diagnosis have led to this enormous disease burden,calling for point-of-care,minimally invasive diagnosis methods.Here,an end-to-end quantitative unified pipeline for diagnosis has been developed,beginning with identification of optimal biomarkers,concurrent design of toehold switch sensors,and finally simulation of the designed diagnostic circuits to assess performance.Using miRNA expression data in the public domain,we identified miR-21-5p and miR-20a-5p as blood-based miRNA biomarkers specific to early-stage cervical cancer employing a multi-tier algorithmic screening.Synthetic riboregulators called toehold switches specific to the biomarker panel were then designed.To predict the dynamic range of toehold switches for use in genetic circuits as biosensors,we used a generic grammar of these switches,and built a neural network model of dynamic range using thermodynamic features derived from mRNA secondary structure and interaction.Second-generation toehold switches were used to overcome the design challenges associated with miRNA biomarkers.The resultant model yielded an adj.R^(2)~0.71,outperforming earlier models of toehold-switch dynamic range.Reaction kinetics modelling was performed to predict the sensitivity of the second-generation toehold switches to the miRNA biomarkers.Simulations showed a linear response between 10 nM and 100 nM before saturation.Our study demonstrates an end-to-end computational workflow for the efficient design of genetic circuits geared towards the effective detection of unique genomic/nucleic-acid signatures.The approach has the potential to replace iterative experimental trial and error,and focus time,money,and efforts.All software including the toehold grammar parser,neural network model and reaction kinetics simulation are available as open-source software(https://github.com/SASTRA-iGEM2019)under GNU GPLv3 licence.