China Safety Science Journal

An model for evaluating urban resilience to rainstorm flood disasters

CHEN Changkun, CHEN Yiqin, SHI Bo, XU Tong

2018, 28(4): 1-6. doi:10.16265/j.cnki.issn1003-3033.2018.04.001

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In order to quantitatively assess the city's ability to cope with rainstorm flood disasters, the authors devoted themselves to building an evaluation model based on resilient theories and TOPSIS. An urban resilience evaluation index system containing 3 first level indexes and 25 secondary indexes was established after considering the three attributes of resilience: resistance, recovery capability and adaptive capacity. Based on TOPSIS improved by KL formula, the KL-TOPSIS comprehensive evaluation model of urban resilience was built. The relevant data on Wuhan city from 2009 to 2015 were taken as an example, this model was used to evaluate the Wuhan urban resilience to rainstorm flood disasters. The result shows the model can give the level changes of urban resilience, resistance, recovery capability and adaptive capacity in a certain period of time, and that based on the comparative analysis of these, the weak link in the city to cope with rainstorm flood disasters can be found out, and the strengthening-resilience suggestions can be put forward.

Study on shortcomings in rules for investigation and analysis of casualty accidents of enterprise staff and workers and suggestions for classification of accident causes

FU Gui, JIA Qingsong, XU Surui

2018, 28(4): 7-12. doi:10.16265/j.cnki.issn1003-3033.2018.04.002

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In order to clearly identify the causes of the accident, this article mainly uses the thoughts of independence and exhaustion in Mutually Exclusive Collectively Exhaustive (MECE) analysis to test the scientificalness of the classification of the direct and indirect causes of accident in GB6442-1986, and finally draws the shortcomings in the classification of accident causes in GB6442-1986 from three perspectives: independence and exhaustion, scope of application and origin of accident-causing theory. After that, this article introduces the 24Model which divides the causes of accident into organization and individual to redefine unsafe acts and unsafe conditions, uses the new definition and classification to reclassify the items of direct and indirect causes in GB6442-1986.The results show that the new definitions and classifications contain all the causes mentioned in GB6442-1986 and can disperse and locate them at various levels or stages in 24Model.

Analysis of driving fatigue detection based on fuzzy entropy of EEG signals

HU Jianfeng, WANG Taotao

2018, 28(4): 13-18. doi:10.16265/j.cnki.issn1003-3033.2018.04.003

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To prevent traffic accidents caused by driver fatigue, this study was aimed at developing a driving fatigue detection method based on EEG signal and fuzzy entropy. Firstly, EEG signals during simulated normal driving and simulated fatigue driving were acquired from 28 testees. Secondly, the FE values were calculated based on the EEG signals of two driving states. Then four classifiers (including random forest(RF), support vector machine(SVM), decision tree(DT)and K-nearest neighbor(KNN)) were employed for detecting fatigue state. Finally, multiple performance indicators and ROC curve were adopted to analyze and compare the performance of driver fatigue detection. The results show that the FE value of fatigue driving based on EEG was significantly higher than that of normal driving, all four classifiers can detect driver fatigue state effectively, and K-nearest neighbor classifier achieves the optimal accuracy of 97.4%, and that the driver fatigue detection method based on fuzzy entropy of EEG signals has good robustness and stability.

Study on drivers' safe driving characteristics on curve road

WU Fuwei, FU Rui, WANG Xin, WANG Chang

2018, 28(4): 19-23. doi:10.16265/j.cnki.issn1003-3033.2018.04.004

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In order to research drivers' driving safety features in the process of curving driving, driving simulation experiments were carried out with 30 testees. During the experiments, the testees' operation data and the eye movement data were collected using DLab and the faceLAB 5 non-contact eye tracker respectively. Influences of curve radius on their visual search and operational mode were studied. Results show that the horizontal visual line concentrated in [-10 ° to 10 °], the mean of the horizontal fixation angle is a quadratic function relation of the curve radius, that as the curve radius increases, their horizontal fixation angle shifts to the right, that in terms of operation mode, there is a negative correlation between the steering wheel angle and the curve radius, that the relationship between vehicle lateral position and the curve radius is not obvious, and that drivers should pay attention to the traffic information on the curve side and control the vehicle driving along the curve.

Prediction of destroyed floor depth based on SO-ELM-Boosting model

SHAO Liangshan, ZHOU Yu

2018, 28(4): 24-29. doi:10.16265/j.cnki.issn1003-3033.2018.04.005

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In order to predict seam destroyed floor depth accurately, firstly, main factors affecting destroyed floor depth were identified to futher determine the evaluation indicators on the basis of a comprehensive analysis. ELM optimizing the input weights and hidden layer bias by PSO was chosen as a base predictor, Boosting as a ensemble learning framework, and a strong predictor model was built for destroyed floor depth based on PSO-ELM-Boosting theory. Then, effect of combination of ELM hidden layer nodes and base predictor number on the prediction result was studied, and the most superior combination of both was obtained. Besides, the "weight expansion" issues were avoided by controlling the weight of sample. Finally, according to the 64 available data from destroyed floor depth measurement, a series of experiments were carried out to compare and analyze the prediction results obtained by using the PSO-ELM-Boosting model and others. The experimental results show that the PSO-ELM-Boosting model has lower mean absolute percentage error(4.54%), mean squared error(0.429 2 m²) and higher R² (0.956 5),which illustrates the effectiveness of the PSO-ELM-Boosting model.

Effects of scenarios on drivers' hazard perception evaluation result

WU Chu'na, ZENG Cheng

2018, 28(4): 30-35. doi:10.16265/j.cnki.issn1003-3033.2018.04.006

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To improve the reliability and validity of evaluation results of drivers obtained by using drivers' hazard perception evaluation systems, the effects of evaluation scenarios on evaluation result were discussed. Firstly, the similarities and differences between the evaluation scenarios in various types of evaluation systems were analyzed. Then, as evaluation scenarios are generally dangerous scenarios, the effects of dangerous scenarios on evaluation results were analyzed through systematically reviewing the definition, types and risk degrees of dangerous scenarios. Finally, through analyzing the advantages and disadvantages of the static and dynamic scenarios, the effects of scenarios forms on evaluation results were explored. The results indicate that the higher the consistency between the subjective and objective risks in dangerous scenarios, the better the reliability and validity of the scenarios results, that the static and dynamic scenarios have their advantages and disadvantages, that the static scenarios can effectively avoid the ambiguity of the evaluation results and the driver's tiredness and boredom effect, and that the dynamic scenarios are more conducive to the understanding of dangerous scenarios and are closer to the hazard perception working mechanism when the driver is actually driving.

Experimental study on effect of particle size on lignite critical self-ignition temperature

ZHANG Xiaoming, WU Qi, ZHANG Hemeng, WANG Yongjun, SASAKI Kyuro

2018, 28(4): 36-41. doi:10.16265/j.cnki.issn1003-3033.2018.04.007

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Based on the Frank-Kamenetskii theory and the open constant temperature heating method, characteristics of lignite spontaneous combustion were studied. 6 lignite coal samples different in particle size were put into 5, 10 and 15 cm in length cube basket, and 18 coal piles. Experiments were carried out under different constant temperature conditions to study the temperature rise process of the coal pile and to investigate the effect of particle size on the critical self-ignition temperature of the spontaneous combustion stage during coal oxidation. The experimental results show that the temperature rise process of the coal pile can be divided into four stages, an initial temperature increase stage, a slow temperature rise stage, a rapid temperature rise stage, and a spontaneous combustion (or temperature drop) stage, that under constant coal pile volume conditions, the smaller the particle size, the lower the critical self-spontaneous combustion point, and that with the increase of the coal pile size, the effect of particle size on coal critical self-ignition temperature is gradually weakened until it can be ignored.

Effect of storage environment on burning behavior of lint

ZHUO Ping, NI Zhaopeng, LI Xiangmei, LI Qiang, YAN Keqin

2018, 28(4): 42-46. doi:10.16265/j.cnki.issn1003-3033.2018.04.008

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For the sake of preventing effectively fire accidents in the lint warehouse, experiments were carried out by using the combustion heat release rate test method, the effects of storage time, environmental temperature, humidity and moisture content on the combustion properties of lint were studied by cone calorimeter, the corresponding suggestions on the safety management of the lint warehouse were put forward. The results show that the longer the storage time, the shorter the ignition time of lint sample,the higher the peak value of heat release rate, the higher the fire risk,thus lint bales should be stored separately in accordance with the storage time, that in a high temperature and high humidity environment, lint bales are more flammable, the speed of fire spread increases, therefore in summer, environmental monitoring and management of the lint warehouse should be strengthened, and appropriate measures for cooling and ventilation should be taken, and that the use of water in fighting the cotton stacking fire can only play a cooling effect and it is difficult to stop burning, so the way of physical isolation should be added to the firefighting of lint warehouse.

Experimental study on propagation characteristics of horizontal smoldering combustion of coal pile

QI Guansheng, LI Min, YANG Husheng, WANG Deming, MA Liyang

2018, 28(4): 47-52. doi:10.16265/j.cnki.issn1003-3033.2018.04.009

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In order to explore the temperature distribution and its dynamic development process of the smoldering combustion of coal pile in the closed fire zone, experiments were carried out on smoldering combustion of coal pile. The results show that there is a temperature platform in the range of 70-80 ℃ in the forward smoldering combustion process, but there is not such a platform in the reverse smoldering combustion process, that the maximum smoldering reverse temperature is much higher than the smoldering forward temperature, that in horizontal forward smoldering, there is no obvious separation between the pyrolysis frontier and oxidation frontier in the initial stage, and they will separate from each other gradually after a certain period of time, and that in horizontal reverse smoldering, the pyrolysis frontier and oxidation frontier separate from each other obviously from the beginning of ignition.

Effects of particle size on ignition characteristics of corn starch dust cloud

XIE Tian, CHEN Xianfeng, ZHANG Hongming, HUANG Chuyuan, TANG Wenwen, ZHOU Hongwen

2018, 28(4): 53-58. doi:10.16265/j.cnki.issn1003-3033.2018.04.010

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In order to study the ignition mechanism and combustion behavior of corn starch dust, experiments were carried out on corn starch dust by using a synchronous thermal analyzer and a high-speed photography system. The ignition characteristics temperature, ignition characteristic index and ignition delay time of corn starch under different particle size conditions were obtained and the effects of particle size on the ignition characteristics of corn starch dust cloud were analyzed. The results show that with the decrease in the dust particle size, the ignition characteristic temperatures of corn starch decreases, while the ignition index increases, and the corn starch dust cloud in the range of small particle size can ignite easily, that there is a significant quadratic function relationship between the ignition delay time and the particle size, and that the smaller the particle size is, the shorter the ignition time of the corn starch cloud will be.

Application of resilience theory to bridge fire risk assessment

WANG Xiaocui, ZHANG Lijing, TAO Gang, WANG Xiang

2018, 28(4): 59-64. doi:10.16265/j.cnki.issn1003-3033.2018.04.011

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In order to control the risk of bridge fire accidents during operation, a conception of bridge resilience to fire was put forward based on the characteristic of resilience theory. And a model was built for bridge resilience to fire, which was consisted of the fire resistance capacity, absorption capacity, recovery capacity and adaptation capacity. On the basis of considering the the bridge itself, its surrounding environment and related personnel among others, an assessment index system of bridge resilience to fire was established. And the TOPSIS method was applied to the evaluation of bridge resilience to fire. Taizhou Bridge was taken as an example to verify the validity of the model, and the bridge resilience to fire of the five sections of it were evaluted through the proposed method. The five bridge sections were the North line, Main bridge, the Yangzhong line, Jiajiang bridge and the South line respectively. Besides, a comparison was made between the assessment results and the actual situation of the project.The results show that the fire resilience rating of Jiajiang bridge is Class III, the north and south line and Yangzhong line are all Class II, and the main bridge is Class I, that the resilience to fire of Jiajiang bridge is the best among the five sections of Taizhou bridge, followed by the south line, north line and Yangzhong line, while the resilience to fire of the main bridge is the worst, that the evaluation result applying the resilience assessment model based on the TOPSIS method is consistent with the actual condition.

Analysis and study of dynamic response characteristics of advance support disturbed by roadheader

XIE Miao, LI Xiaojing, LIU Zhixiang, WANG Pengfei, LI Yuqi

2018, 28(4): 65-71. doi:10.16265/j.cnki.issn1003-3033.2018.04.012

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To study the dynamic response characteristics of the advanced support under the disturbance of roadheader, based on the theory of overburden strata, a coupled dynamic model was built for advanced support and roof rock. According to empirical formulas of cutting resistance of cutting teeth and traction resistance, a formula was deduced of for vertical force on the cutting head, which was taken as the disturbance excitation of roadheader. Dynamic response simulations and experimental analysis of advanced support were carried out under the above disturbance. The contact stiffness of the advanced support roof and the support stiffness of the advanced support were increased to 2.5×10⁶ kg/s² respectively. That resulted in that the displacement amplitudes of the front and top plates were reduced by 66.78% and 54.73%, 58.91% and 63.78% respectively. When the contact stiffness was increased to the critical value of 1.5×10⁶ kg/s², the vibration suppression of roof displacement decreases. It was found that increasing advance support and roof contact stiffness or advance support stiffness can reduce the effects of the disturbance on advanced support and roof rock displacement, and that roof rock subsidence would be stabilized when the forepoling-roof rock contact stiffness of the advanced support reaches a critical value.

Experimental research on self-adaptive break schedule for human-computer interactive VDT continuous operation

LIAO Bin, FENG Haiqin, LUO Junhao, TENG Huimin, WANG Taixin

2018, 28(4): 72-77. doi:10.16265/j.cnki.issn1003-3033.2018.04.013

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To improve the performance and reliability of VDT continuous operation , a break schedule was studied by carrying out experiments. A fatigue evaluation index system and mental arithmetic experiments were designed after analyzing operation characteristics. Membership functions of fatigue were put forward based on fuzzy statistics and minimum fuzzy entropy, and a fuzzy comprehensive evaluation model was built for getting the operation fatigue evaluation value of time inflection point. The results show that the fuzzy comprehensive evaluation model is suitable for human-computer interactive VDT continuous operation fatigue evaluation, and the self-adaptive break schedule is easy to operate and has little interference to the job.

Progress in study on muscular fatigue caused by pulling task and prospects

YI Cannan, HU Hong, LI Kaiway, TANG Fan, ZUO Huali

2018, 28(4): 78-84. doi:10.16265/j.cnki.issn1003-3033.2018.04.014

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In order to understand the current research status and explore the development of muscular fatigue caused by pulling task being one of the most important MMH methods and to prevent MSDs, publications about muscular fatigue of pulling task were searched and screened and 5 methods were summarized by investigation to MSDs due to pulling task at home and abroad. Based on the classification of the task characteristics and the research object of muscular fatigue for pulling task in MMH, research methods and results were reviewed. After that the existing resultsof research on muscular fatigue for pulling task were discussed and a consideration was given to the results of study on the muscular fatigue casued by other force exerting tasks, 5 new research topics were put forward. Results show that the current research involves two aspects: the development of muscular fatigue for static tasks and that for dynamic tasks, and more and more studies divert to researching dynamic tasks from static ones, that several research methods are synchronously used to enclosure the muscular fatigue, and that less research on dynamic and intermittent pulling tasks has been carried out and it will belong to the topics for future study.

Study on influence of maintenance support strategy on sustainable safety development of airlines

CHEN Fang, HAN Shishuo, GUO Na

2018, 28(4): 85-90. doi:10.16265/j.cnki.issn1003-3033.2018.04.015

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In order to resolve the safety incidents caused by the contradiction between the maintenance capability of the airline maintenance department and the sustainable safety development of the airlines, the main business activities of the maintenance department were systematically analyzed, and a simulation dynamic model was built for the relationshios between the maintenance support capability and the sustainable safety development by using SD method. Through simulation by Vensim, effects of variables such as the workload of the maintenance staff, the employment rate of the new staff, the promotion rate of the senior staff, the approval rate of the aircraft material purchasing plan and the importing rate of the maintenance tools and equipment, on both the number of unsafe events and the quantity of the maintenance supporting flights. The study demonstrates that the strategy of ensuring the punctuality of the airline flight improves greatly the quantity of the maintenance supporting flights, but raises thenumber of unsafe events, that the strategy of ensuring the quality of aircraft maintenance lowers the number of unsafe events, but hinders greatly the development of airlines, and that the strategy giving consideration to both the maintenance capability of the airline maintenance department and the sustainable safety development of the airlines guarantees the maintenance safety, as well as the sustainable development of the airlines.

Research on safety performance of controllers in start-up phase based on step response method

LI Jingqiang, LI Kang, LI Hao, ZHAO Ning

2018, 28(4): 91-96. doi:10.16265/j.cnki.issn1003-3033.2018.04.016

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To analyze the characteristics of safety performance of controllers in the start-up phase, a step response model was built for job performance. The time-domain performance indicators under different damping ratio were determined based on the step response types. 20 min continuous cancellation test data on 20 controllers were collected, and the damping ratio and its time-domain performance indicators were calculated in Matlab. The results indicate that the start-up types of controllers can be divided into oscillation inertia start-up (0<ζ<1) and monotonic inertia start-up (ζ>1) based on the damping ratio, and the start-up speed is inversely proportional to the response time, and that the parameters of the step response curve can be used to identify the start-up type and the start-up speed of controllers effectively.

Evaluation of stability of filling system based on GRA-SPA coupling model

SHI Junwei, CHEN Zhangliang, WU Changyou, SHEN Yingying

2018, 28(4): 97-102. doi:10.16265/j.cnki.issn1003-3033.2018.04.017

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In order to prevent accidents in filling systems of coal mines, the stability of a filling system was studied using the theory of set pair analysis and the grey relational analysis. Firstly, a stability evaluation index system was constructed for the filling system, and the weight of each indicator was determined by the method of AHP. Secondly, a GRA-SPA coupling model was built. The stability level of the filling system was determined, and the trend in its development was forecasted. Then, the countermeasures for improving the stability of the filling system were proposed. The results show that the filling system is "relatively stable", and there is a weak tendency to be "stable", so the monitoring of the filling system should still be strengthened, that the model not only can quantify the identity, difference and opposition of the index factors by the linkage coefficient, but also can get the evaluation conclusion consistent with the actual situation, and that this method can provide a reference for safety management of filling system.

Risk assessment of cotton textile enterprise working environment based on projection pursuit model

ZHANG Weiji, WEI Fei, ZHOU Rui, WANG Shuyun

2018, 28(4): 103-108. doi:10.16265/j.cnki.issn1003-3033.2018.04.018

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In order to prevent incidents and occupational disease in cotton textile enterprise, a projection pursuit model was built. Before building the model, by analyzing the hazards of the working environment in textile enterprises, four factors such as noise, dust, micro-climate and lighting were identified for the assessment. The effective temperature was used as a micro-climate evaluation index, a risk assessment system of textile enterprises was established. The index weight values were calculated by using the projection pursuit and genetic algorithm. An application of the model was made to assessment of risk in a certain cotton textile enterprise in China. The results show that the fore-spinning workshop is a slightly harmful working environment and the spinning workshop is a moderately harmful working environment.

An RVM based safety early warning model for hoisting operation in fabricated building project

LIU Mingqiang, LI Yingpan, WANG Fang, CHEN Xiao, LI Ruige, LI Xiaozhe

2018, 28(4): 109-114. doi:10.16265/j.cnki.issn1003-3033.2018.04.019

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To improve the safety level of construction and get accurate prediction of the safe operation condition of the hoisting operation for fabricated building project, a pre-warning model based on RVM was developed. According to the features of the hoisting operation for fabricated building project, major factors causing frequent accidents were discussed in comparison with the traditional mode, and a early warning index system was established according to 4M1E. The early warning factor was ascertained by attribute reduction algorithm in rough set(RS). A mixed kernel function was introduced and an RVM model was built, whose kernel parameters were determined by IPSO optimization. The model was applied to 5 projects as an example. The data on these projects were input for training and simulation. As the case study shows, the results obtained by using the model are basically consistent with the actual situation.The fitting accuracy, generalization ability and efficiency of the model are better than those of the three other machine learning algorithms.

Research on a multi-step method for prediction of shale gas fracturing well conditon

HU Jinqiu, TIAN Siyun, WAN Fangxing

2018, 28(4): 115-121. doi:10.16265/j.cnki.issn1003-3033.2018.04.020

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In order to realize the prediction of downhole conditions of shale gas fracturing, prevent and control the abnormal conditions in time, a method of building optimized LWLR algorithm based on PF and ARMA model can worked out. The method uses the ARMA model and PF to build a PF_ARMA model and the PF_ARMA model can be used to predict pressure, and the prediction results can be used as the optimization basis for the LWLR model. Finally, LWLR model of optimal pressure parameter was obtained. And a comparison was made between the prediction result by optimized LWLR model and that by the traditional model. The model was used to analyze a shale gas fracturing operation curve. The result shows that the prediction accuracy by the optimized LWLR model is higher than that by any traditional model, and that the change trend and amplitude of the data could be described more accurately by the optimized LWLR model than any traditional model.

Analysis of potential electrode system logging response features of tectonic coal

LIU Yong, CUI Hongqing, YUAN Dongsheng

2018, 28(4): 122-127. doi:10.16265/j.cnki.issn1003-3033.2018.04.021

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In order to improve the accuracy of tectonic coal identification by means of potential electrode system logging curves,a horizontal three layer rock strata model with tectonic coal as the middle layer was established, and four rock strata structure types and four resistivity relationship types were divided. With the given parameters of drilling and mud-invaded zone, numerical simulations of the resistivity relationship types were made by ANSYS 10.0 software, and morphological features and demarcation points features of numerical simulation resultant curves were analyzed. On the basis of logging curves of No.93 coal seam in Taoshan coal mine tectonic coal identification was made, and the identification results were verified by using cataloging data of tectonic coals in Taoshan coal mine. The results demonstrate that there are four basic curve shapes, crest shape, trough shape, rising-step shape, and dropping-step shape, corresponding to the four resistivity relationship types, and that the maxima nodes(turning points) of the concave arcs could be used as the tectonic coal interfaces reference points on the numerical simulation curves, and the errors are less than a half of the electrode spacing.

Experimental study on fracture charge scale effect of coal specimen under uniaxial compression

WANG Yalin, PAN Yishan, MA Xiao, ZHU Xiaojing, LUO Hao

2018, 28(4): 128-132. doi:10.16265/j.cnki.issn1003-3033.2018.04.022

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In order to study the difference in the occurrence and development of fractures in coal samples different in size, experiments were performed. Under uniaxial compression conditions, the relationship between the size of coal and the charge signal of coal fracture was studied by charge induction technology. The results show that electric charge per unit volume is a power function of the volume under uniaxial compression and electric charge per unit area is a power function of the area under uniaxial compression, that the existence of charge scale effect of coal specimen is due to the heterogeneity of coal samples, that there is low-level preexisting fracture in large volume or area coal specimen, so the probability of the expansion of original cracks and the generation and expansion of new cracks is greater in coal samples of large volume or area, and the numerous cracks cause the generation of more electrostatic charges.

Analysis of thermal hazard of tert-butyl peracetate and effects of incompatible substances

SHEN Saili, JIANG Juncheng, ZHANG Wenxing, NI Lei, ZOU Mengya

2018, 28(4): 133-138. doi:10.16265/j.cnki.issn1003-3033.2018.04.023

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In order to analyze the thermal hazard of TBPA, experiments were carried out by using a differential scanning calorimetry (DSC), a Phi-TEC II adiabatic calorimeter and a gas chromatography/mass spectrometry (GC/MS) to study thermal decomposition characteristics of TBPA and the compatibility of TBPA with H₂SO₄/NaOH. Thermal decomposition products of TBPA were analyzed. A probable thermal decomposition scheme was inferred for TBPA. Kinetic parameters, such as the corresponding apparent activation energy, the pre-exponential factor and reaction order were calculated by using the Starink method and the rate constant method, which can be used to calculate θ_d24 (the onset temperature when the TMRad is 24.0 h). The results indicate that under the adiabatic condition, the initial decomposition temperature is 83.0 ℃, adiabatic temperature rise is 214.5 ℃, and θ_d24 is 63.46 ℃, that thermal behavior of TBPA mixed with H₂SO₄ is dangerous considering the lower initial decomposition temperature, and the higher heat release rate of decomposition, that the sodium hydroxide solution has a little effect on TBPA decomposition, and that the process temperature must be strictly controlled during production, storage, and transportation, that NaOH is preferable to H₂SO₄ as the reactant in TBPA synthesis, and that the effect of acidic substances on TBPA decomposition especially need to be noticed.

Evaluation method of coal dust occupational health damage under uncertainty condition and its application

TONG Ruipeng, CHENG Mengzhao, MA Xiaofei, XU Surui

2018, 28(4): 139-144. doi:10.16265/j.cnki.issn1003-3033.2018.04.024

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In order to obtain more reasonable health damage assessment results and identify the most significant factors, a probabilistic risk assessment model was built based on the Monte Carlo simulation and the deterministic health damage assessment method. The health damage level of coal dust was evaluated at four workplaces of a certain coal mine in China, such as coal mining face, heading face, shotcrete point and transshipment point. And, a sensitivity analysis was conducted to analyze the influence of each variable parameter. The results show that for the four workplaces in the coal mine, coal dust health damage has a logarithm normal distribution. The coal miners at heading face are exposed to the highest health damage, followed by coal mining face and shotcrete point, the last is transshipment point. Sensitivity analysis indicate that exposure duration, exposure time, inhalation rate and coal dust concentration at various workplaces have a decisive effect on the evaluation results. The optimization model is effective in solving the uncertainty problem of coal dust occupational health damage assessment.

Dynamic calculation method of safety-civilized measure cost rate of subway project

CHEN Wei, YANG Zhuzhang, RONG Sisi, FU Hongyang

2018, 28(4): 145-150. doi:10.16265/j.cnki.issn1003-3033.2018.04.025

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For the sake of solving the problem that the standard of safety-civilized measure cost rate couldn't work effectively in time for subway project, the rate was studied based on the constraint of time. It was proposed that the subway project safety-civilized measure cost should be analyzed from the two parts of the fixed cost and variable cost according to its definition. On the basis of the analysis, the safety-civilized measure cost was counted and predicted as the molecule of the rate. A model of least squares support vector machine optimized with particle swarm optimization was built to predict the settlement cost which could be used to draw the base data as the denominator of the rate. Thus, a dynamic calculation method of the subway project safety-civilized measure cost rate was worked out. Typical subway projects in Wuhan area were taken as examples to be analyzed. The results show that the rate calculated by the dynamic calculation method can reflect the demands of the subway projects for safe and civilized construction.

Path analysis of impact of individual death on construction safety accident learning

ZHANG Yu, BIAN Xiaoli, LIU Hongyong

2018, 28(4): 151-156. doi:10.16265/j.cnki.issn1003-3033.2018.04.026

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For the sake of improving the accident learning efficiency, a model was built for impact of individual death on construction safety accident learning, after considering the individual death as the inherent characteristics of safety accidents, the information the survivors and the survey group have, and taking the accident characteristics and other sources of information as regulation variables. On the basis of the data collected from 78 investigation reports on construction accidents, the model was verified by using path analysis. The results show that the information from the survivors is helpful in understanding accident and identifying the direct cause, but the "death paradox" exists; the overall impact of the survey group is not significant; the data from other sources as well as the short duration and the open space of the accident have a regulating effect on the relationship above; the witness interview manual should be refined; use of monitoring equipment in the closed spaces should be promoted; all the accident data should be made public; and a adjustment mechanism of the investigation unit should be established.

Dissipative structure theory based model for major decision-making social risk situation discrimination model

CHANG Zhipeng, ZHANG Zengguo, ZHANG Tao, XU Haoyue

2018, 28(4): 157-162. doi:10.16265/j.cnki.issn1003-3033.2018.04.027

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In order to improve the government's ability to manage social risk from major decision-making, a social risk situation discrimination model was built based on the dissipative structure theory. First, the entropy production accumulation and entropy flow accumulation in social system were used to construct a social risk situation discrimination function. The discriminant rule of the function was given according to Brusselator and its transferred meaning. Then, to adapt the nonlinear interaction among social risk factors, fuzzy measure and Choquet integral were used to calculate the entropy production and entropy flow in the social system at the different time nodes. At the same time, a method was worked out to calculate the accumulation of entropy production and the accumulation of entropy flow in the social system. Finally, the model was used to discriminant social risk situation caused by a PX project in a certain city. The results show that both increasing the accumulation of entropy flow and reducing the accumulation of entropy production can decrease the social risk, transforming a dangerous situation to a security situation.

Risk assessment of CTCS-3 train control system based on FMEA and ELECTRE-III

MU Nengye, QIU Zhongquan

2018, 28(4): 163-168. doi:10.16265/j.cnki.issn1003-3033.2018.04.028

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For the sake of enhancing the reliability of CTCS-3 train control system, a novel risk assessment model based on FMEA and ELECTRE-III is built proposed. In the model, IFNs is utilized to characterize the uncertain information, and ELECTRE-III is introduced to construct the outranking relations between PFMs, and then the ranking of PFMs based on risk level is achieved. A case study is introduced to compare the proposed model with the traditional FMEA, the weighted arithmetic average aggregation operator, VIKOR and TOPSIS. The results demonstrate that the model built by the authors of this paper has strong robustness and can effectively overcome the influence of the heterogeneity among the indexes.

Fuzzy comprehensive statistical assessment of highway slope seismic instability scale

LIU Yang, XIANG Bo, ZHANG Jianjing, YAN Kongming, LIAO Weiming

2018, 28(4): 169-174. doi:10.16265/j.cnki.issn1003-3033.2018.04.029

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In view of that the existing method of slope seismicity hazard assessment rarely mentioned instability scale, and that fuzzy comprehensive decision-making method used frequently in hazard assessment has strong subjectivity, the authors of this paper have developed a fuzzy comprehensive statistical method for evaluation of highway slope seismic instability scale. Based on the traditional fuzzy statistical principle, 408 unstable roadway slopes recorded in Post-earthquake investigation data of Wenchuan earthquake were taken as samples, the authors divided the value range for each index of this assessment method into several intervals and conducted fuzzy statistics on every intervals, then the fuzzy statistical results were curve fitted to obtain the interval membership degree of each index. Next, using the fuzzy comprehensive decision-making model, instability scale was determined according to the observed value. At last, the developed assessment method was used to assess the seismic instability scale of other 45 highway slopes. The accuracy of the evaluation results obtained by this method is 88.6%, indicating that the method is effective. Because the method has no other correction process, and that the number of slope samples is relatively small, there is still room for improving the accuracy of this method.

Multi-objective optimization model for water emergency rescue facilities location in reservoir area

ZHANG Jinfeng, HE Yunfeng, WU Xiaohong, LIU Yongsen

2018, 28(4): 175-181. doi:10.16265/j.cnki.issn1003-3033.2018.04.030

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In order to make scientific decisions on emergency rescue facility location of the reservoir water, safety risk weight coefficient was introduced by analyzing the water emergency and rescue facilities optimal location problem thoroughly. A multi-objective optimization location model of emergency rescue facilities was built with fairness, timeliness and reliability as the objective, and the emergency coverage radius was taken as the constraint condition. The MOPSO algorithm was introduced to solve the Pareto optimal solution sets, and the compromise position was an effective tradeoff solution based on the improved TOPSIS algorithm. The model was used to solve a water emergency rescue facilities location problem in a certain reservoir area. The results show that the non-inferior solution fully reflects the trade-off relationship between the fairness, timeliness and reliability in this case, and that the optimal compromise solution of the multi-objective optimization location model can be achieved with the MOPSO and TOPSIS algorithms.

Scheduling model of multipoint-multiclass-rescue-resource in ski resort emergency events

NIU Meng, ZHANG Zikai, LI Jingsheng, QI Hang, JING Hui, WANG Achuan

2018, 28(4): 182-186. doi:10.16265/j.cnki.issn1003-3033.2018.04.031

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In order to allocate the multiclass emergency resources of multiple rescue points to each accident point fairly and reasonably, firstly, the target planning method was used to establish a rescue time fixed multi-class resource dispatching model considering urgency degree and based on the model, a multi-point rescue resource scheduling model showing rescue time by interval numbers was established. A solution algorithm was designed to obtain the optimal resource scheduling scheme. And the effectiveness of the models was illustrated by examples.The results show that the emergency dispatching decision-making scheme based on multiple accidents and multiple resources can overcome greatly blindness of the scheduling, thereby optimize rescue scheme more effectively to reduce overall losses, for the introduction of both urgency degree and rescue time expressed by interval numbers.

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