China Safety Science Journal

Study on target event state and occurrence probability of system fault evolution process

CUI Tiejun, LI Shasha

2021, 31(8): 1-7. doi:10.16265/j.cnki.issn1003-3033.2021.08.001

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In order to study occurrence characteristics of system faults in SFEP, a method to determine target event state and probability was established based on SFN and quantum game theory. Game hypothesis was established based on safe and unsafe behaviors of managers and operators, hybrid strategy probability was represented by quantum mechanics. Then, probability of single event hybrid strategy, quantum game representation of event logic relationship, form of target event state and occurrence probability were studied. The results show that by using static game between manager and operator to determine expected benefits, by derivation can obtain probability of safe and unsafe behaviors of all parties, and obtain probability of all states of target event. However, because benefits of manager and operator determine probability of safe and unsafe behaviors, so probability of all states of target event is not accurate.

Research on relationship between pilots' attention distribution ability and their safety performance

WANG Yonggang, FANG Chenliang

2021, 31(8): 8-13. doi:10.16265/j.cnki.issn1003-3033.2021.08.002

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In order to study relationship between pilots' attention allocation ability and change trend of their safety performance, with 206 pilots' psychological selection written test records and QAR data since their employment as samples, a model for safety performance prediction and evaluation was established by using multi-layer linear model. The results show that attention allocation ability is one of the important factors for pilots' different safety performance, and those with stronger allocation ability results in higher safety performance level in 0-1 year of employment. This ability can lead to significant individual differences in change trend of safety performance level in 1-4 years of employment, and it exerts significant positive influence on decline rate of pilots' safety performance. In other words, the stronger attention allocation ability pilots possess, the more they can inhibit the decline of safety performance.

Research on impacts of destructive leadership on safety performance based on conditional process analysis

FENG Yajuan, XING Zhongchao

2021, 31(8): 14-21. doi:10.16265/j.cnki.issn1003-3033.2021.08.003

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In order to explore impact mechanism and boundary conditions of destructive leadership on employees' safety performance so as to improve it, emotional depletion was introduced as an intermediary variable and self-efficacy as a moderator variable. Then, with grassroots employees of 8 manufacturing enterprises in Liaoning province as investigation objects, conditional process analysis method was adopted to study 315 valid questionnaires from them. The results show that destructive leadership is significantly negatively correlated with self-efficacy and safety performance, and so is emotional exhaustion with them. Destructive leadership has a direct negative impact on safety performance, and can also affect it indirectly through emotional exhaustion. Self-efficacy negatively regulates the relationship between destructive leadership and emotional exhaustion, and then further regulates the latter's mediating role between destructive leadership and safety performance. Improving leadership style, controlling emotional exhaustion and enhancing employees' sense of self-efficacy can effectively improve safety performance and reduce accidents.

Study on interpersonal contagion effect of safety violation behaviors

LIU Lin, WU Jinnan, CHANG Zhipeng

2021, 31(8): 22-29. doi:10.16265/j.cnki.issn1003-3033.2021.08.004

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In order to prevent occurrence of group safety violations, using social learning theory and social information processing theory,PSM method was used to analyze data of 1 294 employees from 25 provinces and municipalities in China. To examine whether there was human-to-human contagion effect of safety violations, and to explore whether there was heterogeneity among different types of enterprises and employees. The results show that interpersonal contagion effect widely exists in enterprises with different risk levels, staff size and ownership, as well as employees with different employment forms and gender. Specifically, a stronger interpersonal contagion effect was found in middle and small-sized enterprises, informal employees and female employees.

Study on recognition of traffic terrorist attacks with limited data samples

YANG Lixia, XU Maozeng, CHEN Renxiang

2021, 31(8): 30-37. doi:10.16265/j.cnki.issn1003-3033.2021.08.005

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In order to solve the problem that data samples for recognition of traffic terrorist attacks are too limited to meet the demand of DNN for massive training data, based on the data-enhanced deep learning, a terrorist attack recognition approach was proposed. Firstly, data enhancement strategy and method were designed to gain enough training samples. Secondly, cost function was calculated via both original and enhanced training samples during network training process to overcome overfitting and improve robustness. Then, DNN was developed by using stacked multiple sparse auto-encoder(SAE) and classification layers. Moreover, feature extraction and pattern recognition were integrated via layer-by-layer self-learning and supervised and reversed fine-tuning of enhanced samples in order to accurately identify attack behaviors. Finally, the proposed approach was illustrated and demonstrated with attack data from global terrorism database(GTD). The results show that the feature extraction ability and recognition results of the enhanced deep learning algorithm have been improved compared with comparison algorithm with limited data samples, and its average recognition accuracy can reach as high as 98.75%.

Impact mechanism of strengths-based psychological climate on employees' safety performance

DING Tianwei, SHEN Yuzhi

2021, 31(8): 38-46. doi:10.16265/j.cnki.issn1003-3033.2021.08.006

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In order to explore influencing factors of employees' safety performance so as to improve it, with work-related flow and organization-based self-esteem as mediating variables, and Zhong-Yong thinking style as a regulating variable, a conceptual model of influence mechanism of strengths-based psychological climate on safety performance was constructed. Then, valid questionnaire responses of 543 employees from high-risk industries who were engaged in production management were collected and a structural equation model was used to test the impact mechanism. The results show that strengths-based psychological climate has a significant positive impact on safety performance. Work-related flow and organization-based self-esteem both play a mediating role between employees' advantage-based psychological atmosphere and safety performance while Zhong-Yong thinking style positively regulates their mediating role.

Correlation analysis of QAR parameters for paired approach lateral position error

ZHANG Zhaoning, CHEN Zichen, LU Fei

2021, 31(8): 47-52. doi:10.16265/j.cnki.issn1003-3033.2021.08.007

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In order to study correlation between pilot operation and environmental factors and lateral position error during aircraft approach,QAR parameters that affect lateral position error based on aircraft lateral position correction process and QAR data were identified. Fuzzy correlation model was established, in which fuzzy C-means (FCM) clustering method was used to cluster sample values of QAR parameters, and membership matrix of each parameter was obtained, combined with Apriori algorithm, association rules among parameters and between parameters and lateral position errors were mined. Correlation was quantified based on association rules, and real sample data of A320-200 was used for correlation analysis. The results show that identified QAR parameters are all related to lateral position error under specified 30% support degree. Elevation angle, slope, rudder position and wind direction have great influence on lateral position error.

Study on supercritical methane adsorption characteristics of coal with medium and high rank

ZHANG Mingjie, YANG Mingxin, YAN Jiangwei, XIE Shuailong, LIANG Ximing, LI Zhe

2021, 31(8): 53-61. doi:10.16265/j.cnki.issn1003-3033.2021.08.008

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In order to reveal supercritical methane adsorption characteristics of coal with medium and high rank, more accurately predict coalbed gas resources and evaluate coalbed gas (gas) extraction effect in deep coal seam, four coal samples with different metamorphic degrees were selected to carry out isothermal adsorption tests by gravimetric method. Based on excess adsorption theory and Langmuir monolayer adsorption theory, adsorption phase density, number of adsorption methane layers and adsorption capacity of methane adsorbed by coal were studied under supercritical state of methane. The results show that excess adsorption capacity of coal appears a maximum value with increase of pressure, methane appears in monolayer arrangement on coal surface, absolute adsorption capacity increases with increase of adsorption pressure, and it increases slowly and tends to be stable when adsorption pressure is close to supercritical pressure 4.59 MPa. In supercritical state, methane adsorption on the surface of coal particles is dominated by monolayer, and two layers of adsorption gradually appear locally. Absolute adsorption capacity of anthracite is positively correlated with metamorphic degree at the same temperature and pressure, and ultimate adsorption capacity of anthracite is about twice that of middle-rank bituminous coal.

Evaluation of safety resilience in tunnel construction based onideal fuzzy matter element

WEI Qiang, LIU Jiaqi, WANG Jingchun, WANG Peng

2021, 31(8): 62-68. doi:10.16265/j.cnki.issn1003-3033.2021.08.009

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In order to ensure safety of tunnel construction, a concept of safety resilience in tunnel construction was put forward based on characteristic of resilience theory. First, considering characteristics of tunnel engineering, engineering geology, emergency management and other factors, evaluation index system of tunnel construction safety and toughness including 9 indexes was determined from resilience attributes of resistance, adaptability and recovery capability. Then, based on ideal fuzzy matter-element, evaluation model of safety resilience in tunnel construction was established. Finally, with reference to Dagala tunnel, resilience rating was class Ⅱ, which was low. The results show that Dagala tunnel system is less able to resist external intrusion and prevent disasters, low level of toughness. Evaluation results of safety resilience in tunnel construction based on ideal fuzzy matter-element are consistent with actual conditions of project.

Corrosion prediction of submarine pipelines based on improved Random Forest model

ZHANG Xinsheng, CAI Baoquan

2021, 31(8): 69-74. doi:10.16265/j.cnki.issn1003-3033.2021.08.010

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In order to improve prediction accuracy of corrosion rate of submarine pipelines, a submarine pipeline corrosion prediction model based on improved Random Forest was established. First, Spearman correlation coefficient was used to analyze correlation of corrosion data of real Marine hanging plates and factor analysis was performed to reduce dimensionality. Then, the K K-fold cross-Nalidation was set to five, K-fold cross-validation was set up, and RFR model was established to train dimensionality reduction data. Finally, output model's cross-validation score, and compare and evaluate model's highest score prediction result with other models. The research results show that average score of improved RFR model is 0.912, which is higher than BP neural network(BPNN) model and support vector regression(SVR) model. Meanwhile, root mean square error(RMSE) and mean absolute error(MAE) of the highest score prediction results of five-fold cross-validation are 1.441 and 1.3 respectively, which are better than corresponding values of contrast model.

Mining association rules of near-misses of hydropower projects construction

CHEN Shu, XI Junbo, WANG Jianping, CHEN Yun

2021, 31(8): 75-82. doi:10.16265/j.cnki.issn1003-3033.2021.08.011

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To efficiently mine the large amount of text data accumulated in the near-misses investigation of hydropower projects, phrase extraction technology based on mutual information and left-right information entropy was adopted to extract structured key phrases from unstructured near-misses data. Sankey diagram was used to describe information flow among characteristics, locations and types of potential hazards. Combined with phrase extraction technology, Apriori association algorithm was optimized, association rules of hidden danger locations and types were mined, association rules network diagram was drawn, and rules were analyzed with Sankey diagram. 13 820 hidden danger data cases of a hydropower station was verified. The results show that near-misses data switch box guardrails is key of hidden perils, such as easy for shelving electric welding machine switch box cable clutter object at gate, such as electric shock stick slope, falling of correlation degree is higher, study provides hidden perils in hydropower engineering and management.

Study on deformation and failure characteristics of deep roadway surrounding rock under excavation unloading disturbance

WANG Xinfeng, HE Yi, LU Mingyuan, GAO Yuhao, LI Shan

2021, 31(8): 83-90. doi:10.16265/j.cnki.issn1003-3033.2021.08.012

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In order to solve problem of surrounding rock instability, deformation and stress failure of deep roadway under disturbance of excavation unloading engineering. Typical deformation characteristics of deep roadway surrounding rock under unloading disturbance were analyzed by adopted analytic hierarchy process(HAP), mathematical calculation and numerical simulation, comprehensive evaluation system of surrounding rock instability was established, as well as space-time evolutionary characteristics of surrounding rock fracture field, stress field and displacement field were obtained. The results show that surrounding rock disturbed by deep excavation has double typical deformation characteristics of internal unloading instability and external nonlinear deformation. Coupling effect of vertical stress and horizontal stress causes deformation and failure of surrounding rock. Surrounding rock of deep excavation roadway has characteristics of large initial deformation, rapid displacement change and strong rheology. Roof subsidence and floor heave are significant characteristics of surrounding rock instability and deformation.

Study on explosion suppression performance of porous polypropylene

YUAN Bihe, ZHANG Yuduo, YUN Yalong, HUANG Chuyuan, CHEN Xianfeng, CHEN Gongqing

2021, 31(8): 91-96. doi:10.16265/j.cnki.issn1003-3033.2021.08.013

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In order to analyze suppression effect of porous materials on gas explosion pressure in pipelines, a self-built gas explosion test platform was used to investigate influencing mechanism of inner diameter, filling position, and filling length of porous polypropylene composite material on explosion pressure. The results show that compared with explosion of empty pipelines, maximum explosion pressure and maximum pressure rise rate are significantly decreased by filling such porous materials. When the material's inner diameter is 0 mm, namely it is solid, and it is put closest to fire source with a filling length of 2 m, it will show the optimal suppression effect, with the maximum explosion pressure value at the pipeline end being attenuated by 69.64%, and maximum rise rate reduced by 58.31%. Changes in inner diameter, filling position and filling length and other factors will all have a significant impact on explosion suppression performance of these materials.

Research on safety control of rigid interface pipelines under subway tunnel excavation

WANG Yu, WANG Kaixuan

2021, 31(8): 97-103. doi:10.16265/j.cnki.issn1003-3033.2021.08.014

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In order to reduce possible pipeline leakage and damage caused by excavation of adjacent metro tunnels, based on soil excavation deformation, pipe-soil relative stiffness and material strength criterion, a method of allowable maximum settlement for rigid interface pipelines was established through analytical derivation for single-track tunnels and double-track ones respectively. Then, design charts of settlement control for pipelines of different materials were proposed. The results show that control standards of large-scale pipelines is relatively stricter, and the order of pipeline risk sources considering settlement control is like reinforced concrete pipeline > centrifugal cast iron pipeline > steel pipeline > nodular cast iron pipeline. Moreover, the modified standards with consideration to pipe-soil relative stiffness is more reasonable, and when pipe-tunnel is vertical and relative stiffness is small, standards will be stricter, which should be paid close attention to.

Experimental research on influencing factors of natural frequency of coal

REN Yongjie, WEI Jianping, WEN Zhihui, ZHANG Junzhao, YAO Shuai

2021, 31(8): 104-111. doi:10.16265/j.cnki.issn1003-3033.2021.08.015

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In order to explore dominant frequency of vibration wave increasing permeability of coal, a coal natural frequency test system was built based on knocking method test principle, and coal natural frequency was studied from three aspects: coal size, moisture content, and hole defects. The research results show that Hanning window is better than rectangular window and exponential window in FFT analysis of vibration signal. On this basis, ranges of the first-order and second-order natural frequencies for four different coal groups are 11.1-17.2 Hz and 35.0-40.6 Hz, respectively. Increase of moisture content reduces coal natural frequency, and variation of first-order natural frequency is more sensitive when moisture content is lower. Influence of hole volume on natural frequency of coal has limitations. Variation amplitude of the first and second natural frequencies of coal with different pore volume is within 5.2% and 6.5% respectively. Main influences of vibration wave on coal natural frequency are plastic deformation and evolution of whole defect of coal.

Selection of safety monitoring parameters and layout ofmeasuring points for tower crane

ZHANG Chong, ZHAO Tingsheng, JIANG Ling, WANG Xin, TANG Jingjing

2021, 31(8): 112-118. doi:10.16265/j.cnki.issn1003-3033.2021.08.016

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In order to monitor structural safety status during the operation of tower crane, improve the quality of safety technology management of tower crane, firstly, according to characteristics of structure motion, monitoring parameters were divided into static monitoring parameters and dynamic monitoring parameters.Then, principles of selecting static measuring points and dynamic measuring points were proposed, and layout method of stress, deformation, temperature, wind load, acceleration and other types of measuring points were given. Finally, taking tower crane in service of Lepu building in Shenzhen as monitoring object, this method was applied to implement structural safety monitoring of tower crane.The results show that monitoring data of each measuring point are in good agreement with the numerical analysis results.Tower crane in the use of the process is always in a safe state.

Coupling analysis on disaster-inducing factors for large deformation accidents in soft rock tunnels

DAI Shiwei, LIU Xinxin, WAN Fei

2021, 31(8): 119-124. doi:10.16265/j.cnki.issn1003-3033.2021.08.017

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In order to reduce influence of experts' subjective judgment on evaluation of large deformation accidents in soft rock tunnels, a reverse analysis method is proposed to study coupling mechanism of disaster-inducing factors. Based on investigation into 69 cases, main disaster-inducing factors and their frequency rates were analyzed. Then, according to the first 4 major factors and theirs correlation, a N-K model-based coupling model of all factors was established by studying their coupling paths and coupling process via using system dynamics theory. Finally, their coupling correlation values were calculated and ranking of coupling influence was obtained in accordance with the values. The results show that the order of their coupling influence goes as coupling of four factors, surrounding rock lithology, groundwater, geostress and support strength > that of three, surrounding rock lithology, groundwater and geostress > coupling of two, groundwater and geostress. Although groundwater and geostress are two factors coupling, they produce bigger coupling value than that of three factors, so they should be paid special attention and well controlled before and after construction.

Review on dilemma zone of signal-controlled intersections on urban roads

WANG Jiawen, YOU Quan, ZHOU Xizhao

2021, 31(8): 125-131. doi:10.16265/j.cnki.issn1003-3033.2021.08.018

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In order to further understand and solve problem of urban road signal control intersection dilemma zone, definition, basic nature, driver behavior and management and control of dilemma zones were concluded and summarized. Firstly, basic definitions and properties of two dilemma zones were depicted and reviewed. Then, research methods of driver behaviors on decision making process in dilemma zone were analyzed and summarized. Finally, basic principles and implementation effects of various management and control methods in the dilemma zone were introduced. The results show that lack and deficiency of driver behavior research on decision making process. Finally, basic principles and implementation of various management methods in dilemma zone are introduced. The results show that basic properties of existing dilemmas are not clear and unified.In the aspect of driver behavior decision-making, qualitative analysis is main method, and quantitative analysis is lack.In terms of management and control means of dilemma zone, proposed traffic management and control methods can not completely eliminate dilemma zone, fundamental reason is difference between environment of urban road intersection and driver's cognition.

A review of research on fire safety codes and fire science in urban utility tunnels

YANG Lizhong, YE Kai

2021, 31(8): 132-140. doi:10.16265/j.cnki.issn1003-3033.2021.08.019

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In order to systematically study theachievements and deficiencies in current work of fire safety standardization and research, basic concepts of urban utility tunnels were briefly introduced, followed by the development history of domestic and overseas utility tunnel systems. Then, related fire risks were analyzed, and differences between urban utility tunnels fires and common traffic tunnel fires were discussed. Thirdly, achievements and overall progress of urban utility tunnels fire safety research were reviewed from theperspectives of practical application and fundamental problems. Finally, differences between domestic and foreign fire codes as well as development of domestic standards were summarized, and a comprehensive outlook on future research directions was elaborated. The results show that research methods on fundamental problems were mainly those used in the field of traffic tunnels, and its research content is limited with topics being loosely connected. Moreover, its practical applications are mainly about discussions on engineering experience, and specialized fire codes are generally lacked.

Vulnerability research of rail transit network under bus connection scenarios

LU Qingchang, CUI Xin, XU Biao, LIU Peng, WANG Yan

2021, 31(8): 141-146. doi:10.16265/j.cnki.issn1003-3033.2021.08.020

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In order to evaluate vulnerability of rail transit network in emergencies accurately and improve ability of resisting network risks, based on research of rail transit topology vulnerability, actual passenger flow in network and connecting effect of public transport on passenger flow under scenario of station failure was consided, a vulnerability assessment model was constructed based on average travel time loss of passengers, taking Shanghai Metro network as an example. At the same time, vulnerability of rail transit network under different bus connection efficiency was analyzed. The results show that under bus connection scenarios, stations with high time weighted degree and passengers weighted betweenness will cause more average travel time loss once these stations failed. In the actual emergency connection management, priority should be given to these stations. In addition, the higher the bus connection efficiency is, the lower the vulnerability of rail transit network will be. When connection efficiency is higher than 0.4, the average travel time loss of passengers can be reduced to less than 5%.

IHFACS-BN safety assessment model for large-span steel structure construction and its application

HU Yunpin, LI Chao, LI Zongliang, YANG Daohe

2021, 31(8): 147-154. doi:10.16265/j.cnki.issn1003-3033.2021.08.021

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In order to reduce construction accidents of long-span steel structures, a risk evaluation model for them based on IHFACS and BN was proposed. Firstly, HFACS method was introduced and improved based on engineering practice. Secondly, safety risks were comprehensively identified by using IHFACS, and an evaluation index system was constructed by adopting RS method. Then, according to field data and fuzzy set method, prior probability of each BN root node and conditional probability distribution between nodes were determined, the system's failure probability was calculated by GeNIe software, and key risk factors were analyzed. Finally, with Kunming airport expansion project as an example, the model's effectiveness and advantages were verified. The results show that its calculated outcomes are basically consistent with reality, and the overall safety risk probability of the project is 57.62%. It is also found that misalignment of welds, pores, slag inclusion and improper removal of supporting tire frames all feature a susceptibility above 20%, and they make the key risk factors in large-span steel structure construction.

Self-adaptive adjustment method of automation level for SPO

ZHANG Tongrong, SHI Tongyu, WEI Zhiqiang

2021, 31(8): 155-164. doi:10.16265/j.cnki.issn1003-3033.2021.08.022

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In response to the needs of SPO cockpit automation, a self-adaptive architecture for cockpit human-computer interaction was proposed. Firstly, a cognitive status assessment model, a task cognitive demand model and a cognitive prediction model were established based on physiological indicators as well as continuous monitoring of aircraft operating status parameters and environmental parameters. Then, simulation experiments were conducted to verify changes in physiological indicators and cognitive status of pilots with different external conditions and automation levels. Finally, a self-adaptive adjustment model of automation level was developed to adjust automation flexibly and allocate workload and automation dynamically. The results show that the self-adaptive framework for human-computer interaction based on expert system can assess pilots' cognitive status, reasonably allocate cockpit workload through real-time change of automation level, thereby stabilizing pilots' load index at about 0.4 and slowing down fatigue accumulation so as to maintain the best cognitive status.

Spatial prediction model for risk points of non-motor vehicle conflict in intersections

WU Chengcheng, CHEN Dawei

2021, 31(8): 165-171. doi:10.16265/j.cnki.issn1003-3033.2021.08.023

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In order to quantitatively identify and predict traffic risk points of non-motor vehicle conflict in intersections, visibility graph analysis method and random forest model were adopted to establish a spatial model to predict conflict points with their severity. Then, existing quantitative conflict indexes were improved so that cross conflicts, lateral scraping conflicts and accidents could be identified quantitatively, and avoidance characteristic parameter was adjusted according to avoidance trend of non-motor vehicles. Finally, verification was conducted with four typical intersections in Nanjing city as cases. The results show that the improved index can effectively complement missing values of current index in non-motor vehicle conflict quantization. And the prediction model based on visibility graph analysis and random forest model can better realize quantitative prediction and error evaluation of conflict risk points. The overall error between prediction area and actual conflict area of cases is 6.76%, which indicates a great prediction accuracy.

Experimental study on pedestrian evacuation considering small group behavior

GENG Qi, WANG Weili

2021, 31(8): 172-179. doi:10.16265/j.cnki.issn1003-3033.2021.08.024

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In order to explore influence of small group behavior on decision-making and movement process of pedestrian evacuation, a series of evacuation experiments in buildings with complex layout were carried out. Participants were divided into 24 groups based on sizes of small group and their familiarity degree with layout, and experiment data of exit selection, evacuation path, evacuation speed and decision-making time of each group were obtained and analyzed. The results show that evacuation speed of small groups is slower than that of individuals, but has no correlation with group size. And groups with better familiarity of building layout demonstrate higher evacuation efficiency. In addition, compared with individuals, small groups take more time in decision-making, and pedestrians tend to choose vertical links such as stairs to continue evacuation when facing multiple evacuation routes.

Construction of evaluation index system for emergency rescue capabilities of mine rescue teams

YANG Sanjun, JING Yaru, JIANG Runfa

2021, 31(8): 180-188. doi:10.16265/j.cnki.issn1003-3033.2021.08.025

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In order to effectively evaluate emergency rescue capabilities of mine rescue teams, and to develop more scientific rescue operations, dimensions of influencing factors on such capabilities were defined according to analysis on typical mine accidents. Then, a questionnaire was designed based on literature and expert opinions, its reliability and validity were tested by exploratory factor analysis, and indicators of emergency rescue capabilities were finally selected and determined. Finally, a capability evaluation model was established by utilizing TOPSIS, and applied to the actual case of national mine emergency rescue teams K₁, K₂ and K₃. The results show that emergency rescue capability can be evaluated in five dimensions from 5 first-level indexes, namely command and management, organization construction, professional rescue, comprehensive physical fitness, emergency resources, and 28 second-level ones. And according to the evaluation model, the rescue teams rank as K₂>K₁>K₃ in terms of their capabilities.

Injury severity assessment of wounded based on cluster analysis and PCA

CHEN Changkun, WANG Xiaoyong, LEI Peng

2021, 31(8): 189-196. doi:10.16265/j.cnki.issn1003-3033.2021.08.026

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In order to explore correspondence between four vital signs of human body (respiratory, temperature, pulse, blood pressure) and life status of the wounded, firstly, collected data of 50 samples of the wounded were analyzed using descriptive statistics. Then, a method for rapid assessment of injury severity (RAIS) was proposed based on cluster analysis and PCA, and severity of 50 samples was graded accordingly. Finally, difference in assessment results between National Early Warning Score (NEWS) and RAIS was compared and analyzed. The results show that linear function of principal component score obtained through analysis of four vital signs can be used to assess injury severity of the wounded. The greater this score is, the more severe the injury would be. And since contribution rate of first principal component (PC1) is relatively large, PC1 score should be taken as main basis for actual injury severity assessment.

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