An FPGA‑based trigger system for CSHINE

A trigger system of the general function was designed using the commercial module of CAEN V2495 for heavy-ion nuclear reaction experiments at Fermi energies.The system was applied and verified on the compact spectrometer for heavy IoN experiment(CSHINE).Based on the field-programmable logic gate array technology of the command register access and remote computer control operation,trigger functions can be flexibly configured according to experimental physical goals.Using the trigger system on CSHINE,we conducted a beam experiment at 25 MeV/u^(86)Kr+^(124)Sn on the Radioactive Ion Beam Line 1 in Lanzhou,China.The online results demonstrated that the trigger system worked normally and correctly.This system can be extended to other experiments as well.

Digital signal acquisition system for complex nuclear reaction experiments

A digital data-acquisition system based on XIA LLC products was used in a complex nuclear reaction experiment using radioactive ion beams.A flexible trigger system based on a field-programmable gate array(FPGA)parametrization was developed to adapt to different experimental sizes.A user-friendly interface was implemented,which allows converting script language expressions into FPGA internal control parameters.The proposed digital system can be combined with a conventional analog data acquisition system to provide more flexibility.The performance of the combined system was veri-fied using experimental data.

Local Torrential Rainfall Event within a Mei-Yu Season Mesoscale Convective System:Importance of Back-Building Processes

An extreme rainfall event occurred over Hangzhou,China,during the afternoon hours on 24 June 2013.This event occurred under suitable synoptic conditions and the maximum 4-h cumulative rainfall amount was over 150 mm.This rainfall event had two major rainbands.One was caused by a quasi-stationary convective line,and the other by a backbuilding convective line related to the interaction of the outflow boundary from the first rainband and an existing low-level mesoscale convergence line associated with a mei-yu frontal system.The rainfall event lasted 4 h,while the back-building process occurred in 2 h when the extreme rainfall center formed.So far,few studies have examined the back-building processes in the mei-yu season that are caused by the interaction of a mesoscale convergence line and a convective cold pool.The two rainbands are successfully reproduced by the Weather Research and Forecasting(WRF)model with fourlevel,two-way interactive nesting.In the model,new cells repeatedly occur at the west side of older cells,and the backbuilding process occurs in an environment with large CAPE,a low LFC,and plenty of water vapor.Outflows from older cells enhance the low-level convergence that forces new cells.High precipitation efficiency of the back-building training cells leads to accumulated precipitation of over 150 mm.Sensitivity experiments without evaporation of rainwater show that the convective cold pool plays an important role in the organization of the back-building process in the current extreme precipitation case.

Stress triggering effect on the 2022 Honghe M_(S)5.0 earthquake with historical strong earthquakes

The 2022 Honghe M_(S)5.0 seismic event is intriguing due to its occurrence in the south of the Red River Fault,an area historically lacking seismic activities greater than M_(S)5.0.To elucidate the seismogenic mechanism and scrutinize stress-triggered interactions,we calculated co-seismic and post-seismic Coulomb stress alterations induced by nine historical seismic events(M≥6.0).The analysis reveals that these substantial seismic events provoked co-seismic stress augmentations of 1.409 bar and postseismic stress increments of 0.159 bar.Noteworthy seismic events,such as the 1833 Songming,1877Shiping,1913 Eshan,and 1970 Tonghai earthquakes,catalyzed the occurrence of the Honghe earthquake.Areas of heightened future seismic risk include the southern region of the Red River Fault and the eastern segments of the Shiping-Jianshui and Qujiang faults.Additionally,we assessed the correlation between the spatial distribution of aftershocks and the Coulomb stress shift triggered by the mainshock,taking into account the influence of calculation parameter settings.

Byzantine Robust Federated Learning Scheme Based on Backdoor Triggers

Federated learning is widely used to solve the problem of data decentralization and can provide privacy protectionfor data owners. However, since multiple participants are required in federated learning, this allows attackers tocompromise. Byzantine attacks pose great threats to federated learning. Byzantine attackers upload maliciouslycreated local models to the server to affect the prediction performance and training speed of the global model. Todefend against Byzantine attacks, we propose a Byzantine robust federated learning scheme based on backdoortriggers. In our scheme, backdoor triggers are embedded into benign data samples, and then malicious localmodels can be identified by the server according to its validation dataset. Furthermore, we calculate the adjustmentfactors of local models according to the parameters of their final layers, which are used to defend against datapoisoning-based Byzantine attacks. To further enhance the robustness of our scheme, each localmodel is weightedand aggregated according to the number of times it is identified as malicious. Relevant experimental data showthat our scheme is effective against Byzantine attacks in both independent identically distributed (IID) and nonindependentidentically distributed (non-IID) scenarios.

Trigger转座子衍生蛋白1对肝癌细胞生长的影响

细胞周期失调是肿瘤重要的标志之一,生物信息学分析结果表明,Trigger转座子衍生蛋白1(TIGD1)在临床肝癌组织中高表达且与细胞周期相关,但相关机制未知。为了探究TIGD1调控肝癌细胞生长的具体机制,首先,利用shRNA质粒构建靶向敲低TIGD1的肝癌细胞系Hep3B,并分析TIGD1敲低对肝癌细胞生长的影响,结果表明细胞生长受阻;接着,通过细胞流式技术分析TIGD1敲低对肝癌细胞周期进程的影响,结果显示,TIGD1敲低的Hep3B细胞系的细胞周期进程主要阻滞于G2/M期;然后,通过免疫沉淀(IP)实验验证TIGD1可能发生相互结合的蛋白分子,结果表明,TIGD1可能与Aurora激酶相互作用蛋白1(AURKAIP1)存在相互结合,进一步的Co-IP实验证实了TIGD1和AURKAIP1之间的相互作用。已知AURKAIP1可调控Aurora激酶A(AURKA)的蛋白酶体降解途径,AURKA是一种有丝分裂调控蛋白,与细胞周期进程密切相关。文中进一步探究TIGD1对AURKA蛋白水平的影响,实验结果表明,在TIGD1敲低的情况下,AURKA在Hep3B细胞系中的蛋白水平明显下调,mRNA水平没有明显变化。综上所述,TIGD1可能通过调控AURKA在肝癌细胞中的转录后水平来影响细胞周期进程,从而影响肝癌的发生发展。

Characteristics and triggering mechanisms of early negative Indian Ocean Dipole

Negative Indian Ocean Dipole(nIOD)can exert great impacts on global climate and can also strongly influence the climate in China.Early nIOD is a major type of nIOD,which can induce more pronounced climate anomalies in summer than La Niña-related nIOD.However,the characteristics and triggering mechanisms of early nIOD are unclear.Our results based on reanalysis datasets indicate that the early nIOD and La Niña-related nIOD are the two major types of nIOD,and the former accounts for over one third of all the nIOD events in the past six decades.These two types of nIODs are similar in their intensities,but are different in their spatial patterns and seasonal cycles.The early nIOD,which develops in spring and peaks in summer,is one season earlier than the La Niña-related nIOD.The spatial pattern of the wind anomaly associated with early nIOD exhibits a winter monsoon-like pattern,with strong westerly anomalies in the equatorial Indian Ocean and eastly anomalies in the northern Indian Ocean.Opposite to the triggering mechanism of early positve IOD,the early nIOD is induced by delayed Indian summer monsoon onset.The results of this study are helpful for improving the prediction skill of IOD and its climate impacts.

A study of pulsed high voltage driven hollow-cathode electron beam sources through synchronous optical trigger

In this study,a pulsed,high voltage driven hollow-cathode electron beam sources through an optical trigger is designed with characteristics of simple structure,low cost,and easy triggering.To validate the new design,the characteristics of hollow-cathode discharge and electron beam characterization under pulsed high voltage drive are studied experimentally and discussed by discharge characteristics and analyses of waveform details,respectively.The validation experiments indicate that the pulsed high voltage supply significantly improves the frequency and stability of the discharge,which provides a new solution for the realization of a high-frequency,high-energy electron beam source.The peak current amplitude in the high-energy electron beam increases from 6.2 A to 79.6 A,which indicates the pulsed power mode significantly improves the electron beam performance.Besides,increasing the capacitance significantly affects the highcurrent,lower-energy electron beam more than the high-energy electron beam.

Cascading multi-segment rupture process of the 2023 Turkish earthquake doublet on a complex fault system revealed by teleseismic P wave back projection method

In this study,the vertical components of broadband teleseismic P wave data recorded by China Earthquake Network are used to image the rupture processes of the February 6th,2023 Turkish earthquake doublet via back projection analysis.Data in two frequency bands(0.5-2 Hz and 1-3 Hz)are used in the imaging processes.The results show that the rupture of the first event extends about 200 km to the northeast and about 150 km to the southwest,lasting~90 s in total.The southwestern rupture is triggered by the northeastern rupture,demonstrating a sequential bidirectional unilateral rupture pattern.The rupture of the second event extends approximately 80 km in both northeast and west directions,lasting~35 s in total and demonstrates a typical bilateral rupture feature.The cascading ruptures on both sides also reflect the occurrence of selective rupture behaviors on bifurcated faults.In addition,we observe super-shear ruptures on certain fault sections with relatively straight fault structures and sparse aftershocks.

Dynamically triggered seismicity on a tectonic scale:A review

Earthquakes triggered by dynamic disturbances have been confirmed by numerous observations and experiments.In the past several decades,earthquake triggering has attracted increasing attention of scholars in relation to exploring the mechanism of earthquake triggering,earthquake prediction,and the desire to use the mechanism of earthquake triggering to reduce,prevent,or trigger earthquakes.Natural earthquakes and large‐scale explosions are the most common sources of dynamic disturbances that trigger earthquakes.In the past several decades,some models have been developed,including static,dynamic,quasi‐static,and other models.Some reviews have been published,but explosiontriggered seismicity was not included.In recent years,some new results on earthquake triggering have emerged.Therefore,this paper presents a new review to reflect the new results and include the content of explosion‐triggered earthquakes for the reference of scholars in this area.Instead of a complete review of the relevant literature,this paper primarily focuses on the main aspects of dynamic earthquake triggering on a tectonic scale and makes some suggestions on issues that need to be resolved in this area in the future.

Event-Triggered Finite-Time H∞ Filtering for Discrete-Time Nonlinear Stochastic Systems

This paper addresses the problem of event-triggered finite-time H∞ filter design for a class of discrete-time nonlinear stochastic systems with exogenous disturbances. The stochastic Lyapunov-Krasoviskii functional method is adopted to design a filter such that the filtering error system is stochastic finite-time stable (SFTS) and preserves a prescribed performance level according to the pre-defined event-triggered criteria. Based on stochastic differential equations theory, some sufficient conditions for the existence of H∞ filter are obtained for the suggested system by employing linear matrix inequality technique. Finally, the desired H∞ filter gain matrices can be expressed in an explicit form.

The trigger system for the external target experiment in the HIRFL cooling storage ring

A trigger system was designed for the external target experiment in the Cooling Storage Ring （CSR） of the Heavy Ion Research Facility in Lanzhou （HIRFL）. Considering that different detectors are scattered over a large area, the trigger system is designed based on a master-slave structure and fiber-based serial data transmission technique. The trigger logic is organized in hierarchies, and flexible reconfiguration of the trigger function is achieved based on command register access or overall field-programmable gate array （FPGA） logic on-line reconfiguration controlled by remote computers. We also conducted tests to confirm the function of the trigger electronics, and the results indicate that this trigger system works well.

Fixed-Time Cooperative Tracking for Delayed Disturbed Multi-Agent Systems Under Dynamic Event-Triggered Control

Dear editor,Recently,researchers have obtained many new results about the multi-agent systems(MASs)[1]-[3].In[1],the fixed-time cooperative control(FTCC)algorithm of linear MASs with matched disturbances was proposed.The nonholonomic chained-form dynamics case was considered in[2].In[3],the output tracking problem with data packet dropout was solved for high-order MASs.Moreover,delay frequently occurs because of the non-ideal data transmission[4],and the corresponding FTCC algorithm of MASs with delay was given in[5].

A reusable planar triggered spark-gap switch batched-fabricated with PCB technology for medium- and low-voltage pulse power systems

Triggered spark-gap switch is a popular discharge switch for pulse power systems.Previous studies have focused on planarizing this switch using thin film techniques in order to meet the requirements of compact size in the systems.Such switches are one-shot due to electrodes being too thin to sufficiently resist spark-erosion.Additionally,these switches did not employ any structures in securing internal gas composition,resulting in inconsistent performance under harsh atmospheres.In this work,a novel planar triggered spark-gap switch(PTS)with a hermetically sealed cavity was batched-prepared with printed circuit board(PCB)technology,to achieve reusability with low cost.The proposed PTS was inspected by micro-computed tomography to ensure PCB techniques meet the requirements of machining precision.The results from electrical experiments demonstrated that PCB PTS were consistent and reusable with lifespan over 20 times.The calculated switch voltage and circuit current were consistent with those derived from real-world measurements.Finally,PCB PTS was used to introduce hexanitrostilbene(HNS)pellets in a pulse power system to verify its performance.

Delay Trigger in the Application of Network Testing System

The researchers who study the local area network( LAN) eXtension for instrumentation( LXI) instrument are pursuing instrument's high-precision synchronization. In the paper,three synchronization modes were discussed which were clock synchronization, trigger synchronization, and response synchronization. Synchronous process between LXI instruments was analyzed and each time factor affecting the synchronization accuracy was discussed. On the basis of the analysis,it can be found that delay trigger plays an important role in the network testing system's synchronization. Delay trigger can produce an additional time interval to correct the difference of each LXI instrument's response time. Then,a method to realize the delay trigger was introduced. Delay time can be adjustable according to the actual demand. Finally,synchronization accuracy of network testing system can reach nanoseconds.

Clock synchronization design and evaluation for trigger-less data acquisition system

For modern particle physics experiments,trigger-less data acquisition(DAQ) system has been put into practice because of the need of reaction multiplicity and trigger flexibility.In such new DAQ systems,global synchronized clock plays an important role because it affects the granularity of time slice and precision of reference clock.In this paper,a novel synchronized clock distribution method is proposed.With the help of modulation technique,master clock module distributes system clock to each slave module.To synchronize slave clocks,the propagation delay is adjusted and the clock phase is aligned by an FPGA chip automatically.Furthermore,an ADCbased method is proposed to evaluate the performance of multi-module clock synchronization simultaneously.The experiments of a prototype system show that slave clocks can be synchronized less than 100 ps over 150 m range.The proposed method is simple and flexible,and it can be used in trigger-less DAQ system and other applications of clock distribution preciously.

Resilient Event-Triggered Model Predictive Control for Adaptive Cruise Control Under Sensor Attacks

Dear Editor,This letter addresses the resilient model predictive control(MPC)problems for adaptive cruise control(ACC)systems under sensor attacks.In the light of vulnerabilities of ACC systems to sensor attacks,an intrusion detection mechanism is proposed at the controller side to distinguish abnormal data.Then,the robust control gains are derived to design the terminal region constraint for MPC.

Design of online control and monitoring software for the CPPF system in the CMS Level-1 trigger upgrade

The concentration preprocessing and fan-out(CPPF) system is one of the electronic subsystems of the upgraded Compact Muon Solenoid(CMS) Level-1 trigger system. It includes, in hardware, eight specially designed CPPF cards, one CMS card called AMC13, one commercial Micro-TCA Carrier HUB(MCH) card, and a MicroTCA shelf. Powerful online software is needed for the system, including providing reliable configuration and monitoring for the hardware, and a graphical interface for executing all actions and publishing monitoring messages.Further, to control and monitor the large amount of homogeneous hardware, the SoftWare Automating conTrol of Common Hardware(SWATCH) concept was proposed and developed. The SWATCH provides a generic structure and is flexible for customization. The structure includes a hardware access library based on the IPbus protocol, which assumes a virtual 32-bit address/32-bit data bus and builds a simple hardware access layer. Furthermore, the structure provides a graphical user interface, which is based on modern web technology and is accessible by web page. The CPPF controlling and monitoring online software was also customized from a common SWATCH cell, and provides afinite state machine(FSM) for configuring the entire CPPF hardware, and five monitoring objects for periodically collecting monitoring data from five main functional modules in the CPPF hardware. This paper introduces the details of the CPPF SWATCH cell development.

Trigger control characteristics of fuze-recoil simulation system based on electromagnetic launcher

Fuze is the information processing and control unit of the ammunition, so the quality of the fuze becomes one of the most important aspects of ammunition detection. Since using recoil force is a common method to the arm fuze, its dynamic simulation test has always been the focus of the fuze test research. A new fuze recoil environmental simulation method is proposed based on the electromagnetic launcher. Then the trigger control characteristics of the fuze recoil simulation system and the influence of the trigger position on the recoil force are studied. The results of the study show that although the pulse width of the armature force curve can be changed by adjusting the trigger position, due to the limit of the range, there also exists the contradiction that the electromagnetic pulse width gets narrow with the increase of electromagnetic force peak. Thus, it cannot meet the requirements of the fuze launch recoil simulation. In order to make the recoil force close to the actual environment, the multi-stage trigger control characteristics are analyzed, and the influence of trigger position on recoil environmental force characteristics is studied. Then a fuze launch recoil environmental simulation platform is established and continuous electromagnetic force is achieved by using the trigger strategy. Finally, the experiment is performed to simulate the fuze launch recoil environment and show the feasibility and effectiveness of the proposed theoretical analysis. The major research work of this paper includes studying the composition and basic principle of the simulation system, establishing a launch model to analyze the single-stage and multi-stage coil fuze launch recoil characteristics, designing the test device to verify the correctness and validity of the research. This paper draws the conclusions that the feasibility of the fuze launch environmental simulation based on the electromagnetic launcher is verified, the trigger position has a great influence on force peak continuity, the problems of low maximum overload peak and short peak duration in the multi-stage coil fuze launch environmental simulation can be effectively solved through adjusting the trigger position, the system has creative and extensive application prospects.

Development of a High Power Programmable Precise Time-Delay Trigger/Ignition System for MFCG

High-power precise delay trigger/ignition system is a programmable pulse generator developed for experiment controlling in explosively driven magnetic flux compression generators. Precise delay pulses are generated by the digital circuit, after being magnified and sharpened through multistage isolated amplifiers and rising edge sharpening device, high-voltage steep delay pulses with precision less than μs level are obtained. This system has been used in our compact magnetic flux compression generator experiments in place of the traditional primaeord delay device.