Small-scale fire tests in the underwater tunnel section model with new sidewall smoke extraction

The Shenzhen–Zhongshan Bridge is a 24‐km‐long bridge and tunnel system,including a 6.8-km-long super cross section subsea tunnel.To solve the smoke exhaust problem of a super large cross-section subsea tunnel,the tunnel has a new smoke exhaust system that combines a horizontal smoke exhaust cross section at the top and sidewall smoke exhaust holes.In order to evaluate the potential fire hazards of this type of tunnel,a 1:30 tunnel model was established and 140 smallscale experiments on underwater tunnel fires were conducted.By changing the fire power,fire location,and fan operation mode,different scenarios of submarine immersed tunnel fire were simulated and the related key parameters such as fire smoke diffusion behavior and smoke temperature distribution were studied.On this basis,the optimal smoke control strategy was proposed for different fire scenarios.The research results indicate that the new smoke exhaust system can fully utilize the smoke flow characteristics,significantly improve smoke exhaust efficiency,and increase available evacuation time,thus further enhancing the fire safety of super large cross-section subsea tunnels.

Research on the intelligent internet nursing model based on the child respiratory and asthma control test scale for asthma management of preschool children

BACKGROUND Childhood asthma is a common respiratory ailment that significantly affects preschool children.Effective asthma management in this population is particularly challenging due to limited communication skills in children and the necessity for consistent involvement of a caregiver.With the rise of digital healthcare and the need for innovative interventions,Internet-based models can potentially offer relatively more efficient and patient-tailored care,especially in children.AIM To explore the impact of an intelligent Internet care model based on the child respiratory and asthma control test(TRACK)on asthma management in preschool children.METHODS The study group comprised preschoolers,aged 5 years or younger,that visited the hospital's pediatric outpatient and emergency departments between January 2021 and January 2022.Total of 200 children were evenly and randomly divided into the observation and control groups.The control group received standard treatment in accordance with the 2016 Guidelines for Pediatric Bronchial Asthma and the Global Initiative on Asthma.In addition to above treatment,the observation group was introduced to an intelligent internet nursing model,emphasizing the TRACK scale.Key measures monitored over a six-month period included the frequency of asthma attack,emergency visits,pulmonary function parameters(FEV1,FEV1/FVC,and PEF),monthly TRACK scores,and the SF-12 quality of life assessment.Post-intervention asthma control rates were assessed at six-month follow-up.RESULTS The observation group had fewer asthma attacks and emergency room visits than the control group(P<0.05).After six months of treatment,the children in both groups had higher FEV1,FEV1/FVC,and PEF(P<0.05).Statistically significant differences were observed between the two groups(P<0.05).For six months,children in the observation group had a higher monthly TRACK score than those in the control group(P<0.05).The PCS and MCSSF-12 quality of life scores were relatively higher than those before the nursing period(P<0.05).Furthermore,the groups showed statistically significant differences(P<0.05).The asthma control rate was higher in the observation group than in the control group(P<0.05).CONCLUSION TRACK based Intelligent Internet nursing model may reduce asthma attacks and emergency visits in asthmatic children,improve lung function,quality of life,and the TRACK score and asthma control rate.The effect of nursing was significant,allowing for development of an asthma management model.

Evaluation of Digits-in-Noise Test and Hearing Handicap Inventory for Adults Screening in Patients with Occupational Noise-Induced Hearing Loss

Objective:To explore the clinical evaluation role of the Digits-in-Noise(DIN)test and Hearing Handicap Inventory for Adults Screening(HHIA-S)for patients with occupational noise-induced hearing loss and to observe and analyze their application values.Methods:Fifty patients with suspected occupational noise-induced hearing loss were randomly selected from the Department of Otolaryngology at the hospital as the research target.The collection period for the research cases spanned from January 2022 to November 2023,and all patients had a history of noise exposure.The DIN test and HHIA-S were used for hearing examinations,with clinical,comprehensive diagnosis serving as the gold standard to study their diagnostic performance.Results:The compliance rate of the DIN test was 88.00%,the HHIA-S’s compliance rate was 80.00%,and the combined compliance rate was 94.00%.The compliance rate of the DIN test and the combined compliance rates of the patients were statistically significant compared to the clinical gold standard data(P<0.05),while there was no difference between the compliance rate of the HHIA-S and the gold standard(P>0.05).The data shows that the sensitivity of the combined diagnosis is significantly higher than the sensitivity data of the DIN test and HHIA-S examination alone(P<0.05).Its specificity is 100.00%,and the accuracy data of the joint diagnosis in the degree were higher than those of the DIN test alone(P>0.05)and the HHIA-S alone(P<0.05).Conclusion:For patients with occupational noise-induced hearing loss,the joint evaluation of the DIN test and HHIA-S can significantly improve their diagnostic value with high sensitivity and accuracy.

Digital Simulation of Full Scale Static Test of Aircraft

Full scale aircraft static test is a very important process of aircraft design, it is costly and time consuming. The testing accuracy and validity mainly depend on the rationality of the test scheme design. When the aircraft is being tested, the specimen＇s safety mainly depends on monitoring and understanding the testing data by way of evaluating the coherence with the digital simulation data synchyononsly. The test digital simulation can aid realizing above requirements and improving the test efficiency significantly during test scheme design stage or testing stage respectively. The key technologies and the solving methods of test digital simulation are presented and the application example is given.

Remote Control and Telemetry System for Large-scale Model Test at Sea

Physical testing of large-scale ship models at sea is a new experimental method.It is a cheap and reliable way to research the environment adaptability of a ship in complex and extreme wave conditions.It is necessary to have a stable experimental system for the test.Since the experimental area is large, a remote control system and a telemetry system are essential, and were designed by the authors.An experiment was conducted on the Songhuajiang River to test the systems.The relationship between the model's speed and its electromotor's revolutions was also measured during the model test.The results showed that the two systems make it possible to carry out large-scale model tests at sea.

Real-time multibody modeling and simulation of a scaled bogie test rig

In wheel–rail adhesion studies,most of the test rigs used are simplified designs such as a single wheel or wheelset,but the results may not be accurate.Alternatively,representing the complex system by using a full vehicle model provides accurate results but may incur complexity in design.To trade off accuracy over complexity,a bogie model can be the optimum selection.Furthermore,only a real-time model can replicate its physical counterpart in the time domain.Developing such a model requires broad expertise and appropriate software and hardware.A few published works are available which deal with real-time modeling.However,the influence of the control system has not been included in those works.To address these issues,a real-time scaled bogie test rig including the control system is essential.Therefore,a 1:4 scaled bogie roller rig is developed to study the adhesion between wheel and roller contact.To compare the performances obtained from the scaled bogie test rig and to expand the test applications,a numerical simulation model of that scaled bogie test rig is developed using Gensys multibody software.This model is the complete model of the test rig which delivers more precise results.To exactly represent the physical counterpart system in the time domain,a real-time scaled bogie test rig(RT-SBTR)is developed after four consecutive stages.Then,to simulate the RT-SBTR to solve the internal state equations and functions representing the physical counterpart system in rigs used are simplified designs such as a single wheel or wheelset,but the results may not be accurate.Alternatively,representing the complex system by using a full vehicle model provides accurate results but may incur complexity in design.To trade off accuracy over complexity,a bogie model can be the optimum selection.Furthermore,only a real-time model can replicate its physical counterpart in the time domain.Developing such a model requires broad expertise and appropriate software and hardware.A few published works are available which deal with real-time modeling.However,the influence of the control system has not been included in those works.To address these issues,a real-time scaled bogie test rig including the control system is essential.Therefore,a 1:4 scaled bogie roller rig is developed to study the adhesion between wheel and roller contact.To compare the performances obtained from the scaled bogie test rig and to expand the test applications,a numerical simulation model of that scaled bogie test rig is developed using Gensys multibody software.This model is the complete model of the test rig which delivers more precise results.To exactly represent the physical counterpart system in the time domain,a real-time scaled bogie test rig(RT-SBTR)is developed after four consecutive stages.Then,to simulate the RT-SBTR to solve the internal state equations and functions representing the physical counterpart system in equal or less than actual time,the real-time simulation environment is prepared in two stages.To such end,the computational time improved from 4 times slower than real time to 2 times faster than real time.Finally,the real-time scaled bogie model is also incorporated with the braking control system which slightly reduces the computational performances without affecting real-time capability.

The Nursee-Nurse Collaboration Behavior Scale:Development and psychometric testing

Objective:To develop and test the reliability and validity of a new instrument,the Nurse eNurse Collaboration Behavior Scale(NNCBS).Background:The importance of cooperation among nurses is widely acknowledged,but is a lack of scientific studies regarding the behaviorial interactions associated with nurse enurse relationships throughout the process of patient-centered care.Therefore,there is a great need to develop a reliable scale to measure nurseenurse collaboration behavior,which is what we have generated in this study.Methods:The 46-item Nursee-Nurse Collaboration Scale was developed using a process of item design,refinement,and testing for both reliability and validity.In 2014,the 202 nurses from the International Department of Services participated in this pilot study.Cronbach's a coefficients and testeretest reliability coefficients were calculated in order to evaluate this new scale's internal consistency and stability.Exploratory factor analysis was calculated using a principal factor method with promax rotation to evaluate the scale's validity.Results:Exploratory factor analysis yielded four factors and 23 items.The overall Cronbach's a coefficient of the scale was 0.929.The item-total correlation values were overall high,ranging from 0.427 to 0.751.For the entire scale,the r values of the testeretest reliability correlations were 0.764.Conclusion:The NNCB Scale developed in this study demonstrates acceptable reliability and validity for measuring the level of NNCB.Its implementration on a broader scale would at the very least guide and promote collaborative relationships between nurses involved in patient care.It should be noted that the scale requires further psychometric testing using a larger sample size of nurses who also represent a wider diversity of backgrounds,as well as researchers who are encouraged to improve the instrument.

Scaled down model design of shaking table test of Taizhou Bridge

Taizhou Bridge is the first kilometer level three-pylon two-span suspension bridge in the world and the structural complexity has significant effects on the seismic performance of the bridge. Shaking table test of Taizhou Bridge is arranged to investigate the effects of non-uniform ground motion input, collision between main and side spans and optimal seismic structural system. It's very important and difficult to design and manufacture the scaled down model of Taizhou Bridge used during the shaking table test. The key point is that the girder and pylons are very hard to be manufactured if the similarity ratio is strictly followed. Based on the finite element method (FEM) analysis, a simplified scaled down model is designed and the bending stiffness of the girder and pylon are strictly simulated, and the torsion stiffness and axial stiffness are not strictly simulated. The inner forces and displacements of critical sections, points of simplified model and theoretical model are compared by FEM analysis, and it's found out that the difference between the seismic responses is relatively small. So, the simplified model can be used to conduct the shaking table test by the FEM verification.

Simulation of large-scale numerical substructure in real-time dynamic hybrid testing

A solution scheme is proposed in this paper for an existing RTDHT system to simulate large-scale finite element （FE） numerical substructures. The analysis of the FE numerical substructure is split into response analysis and signal generation tasks, and executed in two different target computers in real-time. One target computer implements the response analysis task, wherein a large time-step is used to solve the FE substructure, and another target computer implements the signal generation task, wherein an interpolation program is used to generate control signals in a small time-step to meet the input demand of the controller. By using this strategy, the scale of the FE numerical substructure simulation may be increased significantly. The proposed scheme is initially verified by two FE numerical substructure models with 98 and 1240 degrees of freedom （DOFs）. Thereafter, RTDHTs of a single frame-foundation structure are implemented where the foundation, considered as the numerical substructure, is simulated by the FE model with 1240 DOFs. Good agreements between the results of the RTDHT and those from the FE analysis in ABAQUS are obtained.

Acoustic emission characterization of microcracking in laboratory-scale hydraulic fracturing tests

Understanding microcracking near coalesced fracture generation is critically important for hydrocarbon and geothermal reservoir characterization as well as damage evaluation in civil engineering structures. Dense and sometimes random microcracking near coalesced fracture formation alters the mechanical properties of the nearby virgin material. Individual microcrack characterization is also significant in quantifying the material changes near the fracture faces （i.e. damage）. Acoustic emission （AE） monitoring and analysis provide unique information regarding the microcracking process temporally, and infor- mation concerning the source characterization of individual microcracks can be extracted. In this context, laboratory hydraulic fracture tests were carried out while monitoring the AEs from several piezoelectric transducers. In-depth post-processing of the AE event data was performed for the purpose of under- standing the individual source mechanisms. Several source characterization techniques including moment tensor inversion, event parametric analysis, and volumetric deformation analysis were adopted. Post-test fracture characterization through coring, slicing and micro-computed tomographic imaging was performed to determine the coalesced fracture location and structure. Distinct differences in fracture characteristics were found spatially in relation to the openhole injection interval. Individual microcrack AE analysis showed substantial energy reduction emanating spatially from the injection interval. It was quantitatively observed that the recorded AE signals provided sufficient information to generalize the damage radiating spatially away from the injection wellbore.

Research on multi-time scale doubly-fed wind turbine test system based on FPGA+CPU heterogeneous calculation

As the proportion of renewable energy increases, the interaction between renewable energy devices and the grid continues to enhance. Therefore, the renewable energy dynamic test in a power system has become more and more important. Traditional dynamic simulation systems and digital-analog hybrid simulation systems are difficult to compromise on the economy, flexibility and accuracy. A multi-time scale test system of doubly fed induction generator based on FPGA+ CPU heterogeneous calculation is proposed in this paper. The proposed test system is based on the ADPSS simulation platform. The power circuit part of the test system is setup up using the EMT(electromagnetic transient simulation) simulation, and the control part uses the actual physical devices. In order to realize the close-loop testing for the physical devices, the power circuit must be simulated in real-time. This paper proposes a multi-time scale simulation algorithm, in which the decoupling component divides the power circuit into a large time scale system and a small time scale system in order to reduce computing effort. This paper also proposes the FPGA+CPU heterogeneous computing architecture for implementing this multitime scale simulation. In FPGA, there is a complete small time-scale EMT engine, which support the flexibly circuit modeling with any topology. Finally, the test system is connected to an DFIG controller based on Labview to verify the feasibility of the test system.

Effect of Rating Scales and Test Parts of Body on the Evaluation Results of Fabric-evoked Prickle

The effect of rating scales and test parts of body on the fabric-evoked prickle evaluation results are studied by carrying out subjective evaluation tests under controlled environment conditions （24 4±1）℃, （65 =l= 5） %RH. Ten college female students aged about 20 were chosen as the subjects, who have participated a preliminary training on subjective prickle evaluation. The prickle of a range of 9 light-weight worsted woven wool and wool blend fabrics and a cotton fabric were tested by using a 1 - 5 rating scale and using a 0 - 10 rating scale respectively at different test parts of body respectively such as forearm, upper arm ball and neck back. The test results were statistically analyzed. It is found that there is a significant correlation coefficient between the evaluation results of using the 1 - 5 rating scale and of using the 0- 10 rating scale. It is also found that there are highly significant correlation coefficients between the evaluation results of using the forearm prickle test and the neck back prickle test, between the evaluation results of using the neck back prickle test and the upper arm ball prickle test, and between the evaluation results of using the forearm prickle test and the upper arm ball prickle test. It is suggested that the forearm prickle test is preferable in evaluating fabric-evoked prickle for its convenience and sensitivity.

3-D Modelling of the Confederation Bridge Using Data of Full Scale Tests

Long-span bridges are special structures that require advanced analysis techniques to examine their performance. This paper presents a procedure developed to model the Confederation Bridge using 3-D beam elements. The model was validated using the data collected before the opening of the bridge to the public. The bridge was instrumented to conduct fullscale static and dynamic tests. The static tests were to measure the deflection of the bridge pier while the dynamic tests to measure the free vibrations of the pier due to a sudden release of the static load. Confederation Bridge is one of the longest reinforced concrete bridges in the world. It connects the province of Prince Edward Island and the province of New Brunswick in Canada. Due to its strategic location and vital role as a transportation link between these two provinces, it was designed using higher safety factors than those for typical highway bridges. After validating the present numerical model, a procedure was developed to evaluate the performance of similar bridges subjected to traffic and seismic loads. It is of interest to note that the foundation stiffness and the modulus of elasticity of the concrete have significant effects on the structural responses of the Confederation Bridge.

SINOPEC's Success in Fixed-bed Methanol-to-Propylene Pilot Scale Tests

The first in China pilot tests of fixed-bed methanol-topropylene unit were successfully implemented at the Yangzi Petrochemical Company(YPC).It is told that this technology has opened up a new process for production of propylene through coal gasification,and China has possessed both the fluidized-bed methanolto-propylene process(F-MTP)and the

RCS SCALE-MODEL-TESTING METHOD BY VARIANCE IN THE SIZE FOR SIMPLY SHAPED SCATTERERS

t According to a general representation of physical scale factor of RCS for variance in the size of simply shaped scatterers, a novel RCS model-testing method is described. The computed results of the prototype scatterers by this method from the model-testing agree well with their measured values both for two kinds of simply shaped scatterers, cylinders and ladder-shaped plates.

The Preliminary Study on the Small-scale Test of the Microbial Quick-degumming Ramie

During the experiments with low temperature plasma treating the ramie degumming microbe,the authors found some kinds of microbe which can degum ramie in 5-6L fluid very quickly.In comparison with some standards of microbiological experiments,5L or 6L-scale can be called the small-scale.Therefore,the authors believe that the experiments of the microbial quick-degumming ramie can be enlarged from the laboratory-scale test to be applied in the future.

荒漠草原不同植物群落蒸散组分特征及其环境因子影响分析

蒸散发是生态水文过程的关键环节,掌握蒸散组分的变化特征及其影响因子,对干旱半干旱地区的可持续发展至关重要。以荒漠草原多年生植物针茅群落和一年生植物猪毛蒿群落为研究对象,利用小型蒸渗仪开展了连续3年监测,分析了蒸散组分的日、月和年变化规律,探讨了影响蒸散组分的主要环境因子。结果表明:晴天时,多年生和一年生植物群落蒸散组分呈先增加后减小的抛物线型,夜间蒸散活动较弱,累积蒸散量较低,不足全天总累积蒸散量的20%;阴天时各蒸散组分无明显峰值,且日累积量均较小,一年生和多年生植物群落的蒸散量、蒸发量和蒸腾量无显著差异;10.64 mm/d及以上降雨对蒸散和蒸发的日变化具有明显影响,随着降雨量的增多,蒸散量和蒸发量也呈增大趋势,但蒸腾量则相对较小。从月动态来看,7—9月占全年蒸散量和蒸发量的一半左右,冬春季蒸散量和蒸发量维持在全年最低水平。年蒸散量与年降雨量接近,而蒸腾量占蒸散量的比例低于10%。总体来看,多年生植物群落蒸散量较一年生植物群落多。采用Mantel检验方法分析不同时间尺度影响蒸散组分的主要气候因素,在小时尺度上太阳辐射与蒸发量和蒸腾量显著性水平较高(P<0.01),但相关性较低(r<0.2);在日尺度上,蒸散量、蒸发量和蒸腾量与降雨量的显著性(P<0.01)和相关性(r≥0.4)均最高;而月尺度上,降雨量和降雨速率与蒸散量、蒸发量的相关性较高(0.2≤r<0.4),但显著性较低(P≥0.05)。因此,蒸散组分受环境因子的影响在不同时间尺度上具有较大差异,说明蒸散组分受多种因子共同影响。

Towards a profile-based writing scale for a local post-admission ESL writing assessment

Post-admission language tests tend to have a restricted range of proficiency levels among test-takers due to considerations made during the admission selection process.Although range restriction can present challenges for proficiency-focused assessment,it can also bring opportunities to zoom in on fine-grained performance profiles of test-takers.This study reports on the validation of a profile-based rating scale for an ESL writing placement test in a US university.The profile-based rating scale was created by employing a three-staged,hybrid scale development approach,to provide not only accurate placement decisions but also fine-grained diagnostic information regarding ESL students’writing performance profiles.The scale strikes a balance between argument development and lexico-grammar,to better account for the range of writing performances among test-takers.To gather validity evidence for the profile-based rating scale,this study employs a sequential,mixed-methods approach to examine the quality of test-taker performances across profiles and rater perceptions on the scale.Nine certified raters were recruited to conduct independent evaluations of lexicogrammar and argumentation on a sample of 150 test-taker performances.These evaluations were subjected to many-facet Rasch measurement analysis to examine the differences across writing performance profiles included in the rating scale.Next,semi-structured,follow-up interviews were conducted with the raters,to complement the quantitative findings on the usability and effectiveness of the scale.The findings provide supportive evidence for the validity of the profile-based rating scale.I argue that by focusing on performance profiles,post-admission language tests can strengthen the alignment across curriculum,instruction,and assessment in ESL writing programs.

时速120 km地铁快线空气动力学试验研究

为探明设计时速120 km快速地铁列车在多区段桥隧衔接线路运行时的气动效应和气密性能,采用实车试验的方法,在武汉某多区段桥隧衔接地铁快线对某4车编组的新研A型密封性地铁列车开展空气动力学测试。实验测试系统采用LL-250-15A型Kulite压力传感器,通过测量列车外部和内部的瞬态压力变化,分析全线路车外压力波动特性,对比沿列车长度方向不同测点位置的压力变化幅值,并分析不同空调状态下的车内压力舒适性。经过3次实验测试分析,该实验的结果具有可重复性。研究结果表明:全线路运行时,列车在隧道段内加减速导致车外压力变化幅值明显大于高架段,气动效应最恶劣的位置为地下段人防门变截面处,列车上行通过该处时车外任意3 s内压力变化幅值为1 071 Pa,下行通过该处时车外任意3 s内压力变化幅值为905 Pa;相对于下行线全线路,上行线车外任意3 s内压力变化幅值大18.3%;列车正线运营时压力波保护阀会在压力变化剧烈区段进行动作响应,列车上行时,空调开启、压力波保护阀正常启用状态下,车内任意3 s内压力变化幅值相对于压力波保护阀打开未启用时减少了16%,下行时,减少了28%,空调压力波保护阀能够有效降低车外压力波动对车内气压变化的影响。本文研究成果可为快速地铁线路设计、地铁列车运营及地铁气密性优化提供参考依据。

合理确定排涝泵站规模的感潮河道模型试验研究

合理确定泵站规模一直是感潮河道排涝工程设计中的关键问题。通过建立物理模型,在选定的水文边界条件和相应工程运行要求下,对某感潮水系两座涌口泵站规模进行试验研究。试验发现,受限于河涌过流能力,泵站规模存在临界值,超过该值后,即使再进一步增加泵站规模,水位也不会继续下降;泵站抽排对某位置水位的降低效应与泵站和该位置之间的距离密切相关,距离越近,水位降低越明显。基于上述认识,通过试验确定了满足水位管控要求的两座泵站规模的合理组合:距离相对较远的温涌泵站为80 m3/s,较近的金紫涌泵站为130 m~3/s。试验方法和主要成果可为工程方案比选及优化提供重要依据,对类似河涌整治工程也具有一定的借鉴意义。