Design of a Modularized Automatic Measurement and Control System for LaserInduced Breakdown Spectrometer

In order to improve the compatibility of laser-induced breakdown spectroscopy( LIBS) instrument for different types of parts and optimize the analysis and testing processes,a modularized automatic measurement and control system was developed. Based on the characteristics of each LIBS component, the following development steps have been performed:( 1) a summary of characteristic parameters of the component are established;( 2) the integration mechanism of multiple electrical interfaces is designed;( 3) the component control instruction library is developed. The experimental results indicate that the measurement and control system is compatible with most LIBS parts in the market.Spectrometer and laser can be compatible with at least three different types of parts. In addition,a multilayer iterative testing process is designed to improve the efficiency of optimization process of LIBS parameters. The experimental results have shown that the automatic optimization of the delay time compared to the manual testing provides significant gain in testing efficiency. The range of delay time in the experiments is 1. 28 to 10. 28 μs and the step value is 1,0. 5,0. 2 and 0. 1 μs. The gain in testing efficiency has been found to be increased by 73. 76%,75. 93%,78. 81% and 80. 42%,respectively.

A review on stress determination and control in metal-based additive manufacturing

Metal additive manufacturing(MAM)is an emerging and disruptive technology that builds three-dimensional(3D)components by adding layer-upon-layer of metallic materials.The complex cyclic thermal history and highly localized energy can produce large temperature gradients,which will,in turn,lead to compressive and tensile stress during the MAM process and eventually result in residual stress.Being an issue of great concern,residual stress,which can cause distortion,delamination,cracking,etc.,is considered a key mechanical quantity that affects the manufacturing quality and service performance of MAM parts.In this review paper,the ongoing work in the field of residual stress determination and control for MAM is described with a particular emphasis on the experimental measurement/control methods and numerical models.We also provide insight on what still requires to be achieved and the research opportunities and challenges.

Occurrence Characteristics and Prevention and Control Measures of Spodoptera frugiperda in Maize

Based on practical work experience,this paper analyzed the occurrence characteristics and control measures of Spodoptera frugiperda in maize.The measures including forecasting and early warning,regional prevention and control,agricultural prevention and control,physical prevention and control,chemical prevention and control,and biological prevention and control can effectively control the damage of S.frugiperda and guarantee the safety of food production.The results will provide some reference for the prevention and control of S.frugiperda.

Construction Technology and Safety Risk Control Measures of Deep Foundation Pit Excavation

Deep foundation pit excavation is a basic and key step involved in modern building construction.In order to ensure the construction quality and safety of deep foundation pits,this paper takes a project as an example to analyze deep foundation pit excavation technology,including the nature of this construction project,the main technical measures in the construction of deep foundation pit,and the analysis of the safety risk prevention and control measures.The purpose of this analysis is to provide scientific reference for the construction quality and safety of deep foundation pits.

Scenario of Infection Prevention and Control Measures for Tuberculosis in Tuberculosis Inpatient and Outpatient Department in Tertiary Care Hospital

Tuberculosis is one of the most important infectious diseases in our country. Also nosocomial infection by tuberculosis can occur, which can be prevented by implementing simple, effective and affordable tuberculosis infection control measures in health care facilities. To evaluate the effectiveness of infection control measures, such study was planned. Questionnaires were administered to all doctors, healthcare workers and servants working in outdoor and indoor department of tuberculosis at tertiary care hospital to assess the knowledge, attitudes and practices on prevention and control of Tuberculosis infection. A scoring system was devised to grade them. One-time audit was also done in outpatient and inpatient department. The analysis showed scoring of poor for doctors, good for nurses and poor forward aids. There is a need to develop strategies for training of health care workers on regular basis in order to reduce the incidence of nosocomial infections. Audit result shows a good level of environmental control measures. Better knowledge, attitude and practices are helpful for the prevention and control of tuberculosis. Also environmental control measures are helpful to prevent infection.

Hydrobios and Control of Eutrophication in Dongping Lake,Shandong Province

The Hydrobios in Dongping Lake, Shandong Province, mainly includes phytoplankton, zooplankton, benthic animals, fishes and hydrophytic vascular plants. Nitrogen and phosphorus are the restrictive factors for the growth and propagation of hydrophyta, therefore the key to the prevention and control of eutrophication in lakes lies in the control of the contents of the two elements in the water. Artificial fishing of algae can reduce the concentrations of trophic substances such as nitrogen and phosphorus in the water bodies, and biological measures may decrease the contents of these trophic substances in the bottom sediments and the water bodies, thereby playing an active role in modifying the eutrophication of the lake.

Prevention and Control Measures of the Occurrence of Ceracris kiangsu Tsai in Sugarcane Areas of Yunnan Province

Ceracris kiangsu Tsai is one of the most widely distributed forest pest.C.kiangsu has migrated from Laos to China this year,with many migration peaks and large population numbers.The main sources of C.kiangsu were from abroad and a small number of native insect sources exist.Most of the immigration sources were from Laos,and a small part originated from Vietnam.The frontier region of Yunnan Province is suitable for the growth of C.kiangsu.It is speculated that the migration frequency of the C.kiangsu from abroad may increase in recent years.In this paper,the typical morphological characteristics,life history,biological characteristics and prevention and control measures of C.kiangsu were summarized.Based on the characteristics of C.kiangsu,and combining actual sugarcane production condition in Yunnan sugarcane areas,we put forward prevention and control strategies and measures.It is suggested that Yunnan Sugarcane areas should pay close attention to the occurrence of C.kiangsu in neighboring countries,monitor the C.kiangsu population dynamics and update pest forecast information in time,and detect and control C.kiangsu in the early period,in order to effectively prevent C.kiangsu and ensure the safety of sugarcane production.

Prevalence Characteristics of Rice Black-streaked Dwarf Virus Disease and Continuous Control Strategies

Through summarizing the prevalence characteristics of rice black-streaked dwarf virus disease(RBSDVD)in Linyi City of Shandong Province,this paper analyzed its prevalence is related to changes in farming and cultivation systems,the increase in the population of venomous Laodelphax striatellus Fallén and its own migration and spread,the poor disease resistance of cultivated varieties,and inadequate time of prevention and control.Besides,based on the practice of local control,it came up with some comprehensive control measures including strengthening monitoring,early warning and forecasting,planting resistant(tolerant)rice varieties according to local conditions,appropriately delaying the sowing(planting)period,supplemented by insect nets to cover seedlings,and making scientific use of chemical control.It is expected to provide a reference for the prevention and control of RBSDVD.

Epidemiological characteristics of varicella in Chongqing,China,2014-2021

Background:To analyze the epidemiological characteristics of varicella epidemics in Chongqing Municipality from 2014 to 2021,and to provide a scientific basis for the formulation of varicella prevention and control measures.Methods:Data on the incidence of varicella outbreaks and vaccination data in Chongqing from 2014 to 2021 were collected through the China Disease Control and Prevention Information System and statistically analyzed using descriptive epidemiological methods.Results:From 2014 to 2021,213,715 cases of varicella were reported in Chongqing Municipality,with an average annual incidence rate of 86.26/100,000,with a statistically significant difference(χ^(2)=24,972.069,P<0.001);varicella incidence is seasonal,with peaks in May/June and October/December each year,presenting a“double-peak distribution”.The average annual incidence rate of varicella in municipal districts was 90.74/100,000,which was higher than that of counties 69.62/100,000 and autonomous counties 84.04/100,000;the average annual incidence rate of varicella in males was 89.37/100,000,and in females,82.22/100,000,with the difference not being statistically significant;the age of onset of the disease was mainly in the group of people under 15 years of age,with a total of 190,021 cases reported(88.9%),with 5-9 years old(35.7%)as the high incidence age group.The incidence occupation was dominated by students in 133,733 cases(62.6%).Conclusion:The overall varicella epidemic in Chongqing is on the rise,and has obvious seasonal,regional and population distribution characteristics.The prevention and control of varicella epidemic should be strengthened,the publicity of varicella vaccine should be increased,and it is recommended that varicella vaccine should be included in the national immunization program.

Analysis of the relationship between environmental policies and air quality during major social events

Based on an analysis of major recent social events in China,such as the 2008 Beijing Olympic Games,2010 Shanghai World Expo,2014 Nanjing Youth Olympic Games,and 2014 Beijing Asia Pacific Economic Cooperation Conference,mandatory,temporary,and indemnificatory quantitative policies aimed at protecting air quality,which were carried out by both central and local governments,made substantial contributions to changes and improvements in air quality.To some extent,the findings show that command and control measures play a significant role in protecting air quality,while the law and economic and voluntary environmental safeguard measures do not during major social events.Therefore,it reminds us the air quality could and will improve not only during major social events but also in the regular days if we implement appropriate environmental policies and safeguard measures.

Diagnosis and Prevention of Colibacillosis in Chickens

The characteristics of chicken colibacillosis are introduced from the aspects of pathogen,epidemiology,clinical symptoms and necropsy,and clinical comprehensive diagnosis and laboratory diagnosis methods are given.The disease is distinguished from diseases with similar symptoms such as chicken chlamydia,chicken streptococcus,chicken necrotic enteritis,broiler ascites syndrome and chicken paratyphoid infections.Eventually,the preventive and therapeutic measures against the disease are put forward.

Diagnosis and Prevention of Duck Virus Enteritis

The characteristics of duck virus enteritis(DVE)are introduced from the aspects of pathogen,epidemiology,clinical symptoms,autopsy pathological changes,etc.,and clinical comprehensive diagnosis and laboratory diagnosis methods are given.The disease is distinguished from similar diseases including duck necrotic enteritis,duck candidiasis,duck hemorrhage,duck coccidiosis and duck vitamin A deficiency.Eventually,the prevention and treatment measures of the disease are put forward.

Site Selection of Waste Slag Yard and Design of Protective Measures in Water Supply Project of Drawing from the Songhua River in Central Cities of Jilin

Water supply project of drawing from the Songhua River in central cities of Jilin is taken as research object.On the basis of analyzing project characteristics and natural conditions of the project area,site selection of waste slag yard of water diversion project and design of water and soil conservation measures are discussed.Rationality of site selection of waste slag yard and pertinence of prevention and control measures of water and soil loss in waste slag yard are analyzed,and comprehensive utilization of waste slag in large-scale production and construction projects is explored.

The Occurrence Mechanism of Geological Disasters and Countermeasures in a Certain Area

In recent years, natural disasters in China have occurred frequently, especially large disasters such as earthquakes, floods and droughts, which have posed a serious threat to local public safety. In addition, the geological environment of local mountainous areas in China is complex and diverse, and climate change is large. Considering the dynamic coupling effect of rainfall conditions to stimulate geological disasters, this paper takes dynamic risk assessment technology as the guide, constructs a dynamic risk early warning model of geological disasters, establishes a prototype system, realizes dynamic risk assessment and emergency early warning of geological disasters at the regional level, and provides feasible technical support for targeted emergency disaster prevention. At the same time, the investigation and evaluation, mechanism research and monitoring and early warning related to the comprehensive prevention and control of geological disasters are important tasks that cannot be ignored, an important link in the emergency response system for geological disasters, and a key stage process to guide scientific disaster prevention. On the basis of exploring the mechanism and catastrophic effect of rainfall to stimulate landslides and mudslides, we will carry out in-depth research on disaster prevention countermeasures such as systematic engineering disposal, monitoring and early warning.

Discussion on the prevention and treatment of COVID-19 by Zhuang Medicine

The Corona Virus Disease 2019(COVID-19)spreads rapidly and is highly infectious.Zhuang Medicine,as a unique ancient and emerging ethnic medicine in Guangxi region,is combined with the unique local climate,geography and population physique,summing up many prevention and control experiences for infectious diseases,such as taking orally and external treatment,focusing on prevention.What is more,the Zhuang Medicine shows its own unique advantages through coming up with the measures of wearing medicine therapy,pyrotechnic fumigation,characteristic medicine baths and taking prescriptions internally.This paper intends to explore the use of Zhuang Medicine to build a disease prevention and control system with characteristics of Zhuang Medicine,trying to make a contribution to the prevention and control and treatment in this region.

Radio Frequency Fingerprint-Based Satellite TT&C Ground Station Identification Method

This study presents a radio frequency(RF)fingerprint identification method combining a convolutional neural network(CNN)and gated recurrent unit(GRU)network to identify measurement and control signals.The proposed algorithm(CNN-GRU)uses a convolutional layer to extract the IQ-related learning timing features.A GRU network extracts timing features at a deeper level before outputting the final identification results.The number of parameters and the algorithm’s complexity are reduced by optimizing the convolutional layer structure and replacing multiple fully-connected layers with gated cyclic units.Simulation experiments show that the algorithm achieves an average identification accuracy of 84.74% at a -10 dB to 20 dB signal-to-noise ratio(SNR)with fewer parameters and less computation than a network model with the same identification rate in a software radio dataset containing multiple USRP X310s from the same manufacturer,with fewer parameters and less computation than a network model with the same identification rate.The algorithm is used to identify measurement and control signals and ensure the security of the measurement and control link with theoretical and engineering applications.

Design and validation of a variable camber wing structure

Variable camber wing technology is one of the important development trends of green aviation at present.Through smooth,seamless,continuous and adaptive change of wing camber,the aerodynamic performance is improved in achieving increase in lift and reduction in resistance and noise.Based on the aerodynamic validation model CAE-AVM,Chinese Aeronautical Establishment(CAE)has carried out the design and validation of a variable camber wing,proposed an aerodynamic deformation matrix for the leading and trailing edges of aircraft wings in takeoff,landing and cruise conditions.Various structures and driving schemes are compared,and several key technology problems of leading and trailing edge deformation are solved.A full-size leading edge wind tunnel test piece with a span of 2.7 m and a trailing edge ground function test piece are developed.The deformation and shape maintenance capabilities of the leading edge is verified under real wind load conditions,and the load bearing and deformation capabilities of the trailing edge is verified under simulated follow-on load.The results indicate that the leading and trailing edges of the variable camber wing can achieve the required deformation angle and have a certain load-bearing capacity.Our study can provide some insights into the application of variable camber wing technology for civil aircraft.

上海市应对新型冠状病毒肺炎疫情综合防控策略

面对新型冠状病毒肺炎疫情,上海市坚决贯彻中央部署要求,采取了最严格、最全面、最积极的防控措施,在短时间内有效地遏制疫情蔓延势头。在疫情防控过程中,准确把握疫情形势变化,因时因势调整防控策略和措施,在严防境外疫情输入、有效处置本土疫情、统筹推动疫情防控和经济社会发展方面形成了行之有效的防控举措,构建起超大城市科学精准防控工作模式。

Telemetering system and its application for fruit cultivation in greenhouses

Circuit of the temperature measurement equipment was improved in order to develop temperature telemetering system for cultivating fruit facilities.The traditional temperature measuring equipments used in monitoring temperature changes in greenhouse include mercury column,merbromine column,kerosene column glass rod thermometer and mechanical inductive thermometer.Compared with the traditional method of temperature measurement the new system reduces the labor requirement and promotes precision monitoring and control of the temperature.In addition,the temperature in the greenhouse was very accurate especially at night or in rainy and snowy weather.This new temperature telemetering system will promote the development of the fruit protection cultivation.

Optimization of COVID-19 prevention and control measures during the Beijing 2022 Winter Olympics:a model-based study

Background:The continuous mutation of severe acute respiratory syndrome coronavirus 2 has made the coronavirus disease 2019(COVID-19)pandemic complicated to predict and posed a severe challenge to the Beijing 2022Winter Olympics and Winter Paralympics held in February and March 2022.Methods:During the preparations for the Beijing 2022 Winter Olympics,we established a dynamic model with pulsedetection and isolation efect to evaluate the efect of epidemic prevention and control measures such as entry policies,contact reduction,nucleic acid testing,tracking,isolation,and health monitoring in a closed-loop managementenvironment,by simulating the transmission dynamics in assumed scenarios.We also compared the importance ofeach parameter in the combination of intervention measures through sensitivity analysis.Results:At the assumed baseline levels,the peak of the epidemic reached on the 57th day.During the simulationperiod(100 days),13,382 people infected COVID-19.The mean and peak values of hospitalized cases were 2650and 6746,respectively.The simulation and sensitivity analysis showed that:(1)the most important measures to stopCOVID-19 transmission during the event were daily nucleic acid testing,reducing contact among people,and dailyhealth monitoring,with cumulative infections at 0.04%,0.14%,and 14.92%of baseline levels,respectively(2)strictlyimplementing the entry policy and reducing the number of cases entering the closed-loop system could delay thepeak of the epidemic by 9 days and provide time for medical resources to be mobilized;(3)the risk of environmentaltransmission was low.Conclusions:Comprehensive measures under certain scenarios such as reducing contact,nucleic acid testing,health monitoring,and timely tracking and isolation could efectively prevent virus transmission.Our research resultsprovided an important reference for formulating prevention and control measures during the Winter Olympics,andno epidemic spread in the closed-loop during the games indirectly proved the rationality of our research results.