Safety Protection Device Research Articles

Crushing performance evaluation of gradient Sierpinski triangular fractal column

Thin-Walled Structures with excellent mechanical properties are the key to the protective system of the vehicle. This paper proposes a novel Sierpinski triangular fractal column with graded thickness (STFC-GT) to improve the crushing stability and energy absorption of Thin-Walled Structures. The crashworthiness of the STFC-GT is investigated through the experimental test and numerical simulation under axial crushing load. The results show that the Sierpinski triangular fractal column contributes to the energy absorption, and the graded thickness design can decrease the initial peak force. Specifically, the energy absorption of STFC-GT improves by 144.22 % from 0th to 2nd. And the initial peak force of 2nd STFC-GT is 55.32 % lower than that of 2nd STFC with uniform thickness. In addition, a theoretical relationship between the parameter configurations and the mean crushing force of STFC-GT are developed using the simplified super folding element theory (SSFE). The maximum error is less than 7.89 % between the theoretical and numerical results. Finally, the influence of gradient types on crushing performance is investigated to determine the optimal gradient configuration and maximize the mechanical performance of the STFC. The research result provides reliable guidance for the design of a new vehicle safety protection device.

Probabilistic risk assessment of fire and explosion of onboard high-pressure hydrogen system

Hydrogen is regarded as a new energy carrier and has broad application prospects. As the leading field of hydrogen energy application, hydrogen fuel cell vehicles (HFCVs) are highly valued in the world. However, due to the flammable and explosive characteristics of hydrogen, its safety issues have attracted much attention, and it is increasingly necessary to understand the possible accident risks of the hydrogen system of HFCVs. In this study, the quantitative risk assessment (QRA) of hydrogen system of HFCV was carried out, and the Bayesian network (BN) analysis model of fire and explosion risk of onboard high-pressure hydrogen system was established. Taking a hydrogen system as an example, BN parameters are quantified based on three quantitative analysis methods: general data, logical judgment and computational simulation, and then the fire and explosion risk and personnel loss degree of the general onboard high-pressure hydrogen system are determined. The results show that when hydrogen release occurs, the probability of explosion is 6.79E-05, the probability of jet fire is 1.53E-04, and the probability of fireball is 5.38E-08. In the case of major damage, there is an 87.15 % probability that an explosion occurred; the reliability of safety protection devices is very important in the process of hydrogen use. It is suggested to optimize the structural layout design of safety components and improve the reliability of protection devices to promote the safe development of hydrogen energy industry such as HFCVs.

The Usage of Personal Protective Equipment (PPE) Among Quarry Workers in Abia and Ebonyi State, South East, Nigeria

Background: Personal protective equipment is a lifesaving equipment which helps in protecting the health of workers. Quarrying activity which is an economic/money marking activity requires workers to be well protected due to the various activities in the quarry sites. Aim: The aim of this work is to assess the usage of personal protective equipment (PPE) among quarry workers in Abia and Ebonyi States, South East, Nigeria. Method: A cross sectional study on the usage of personal protective equipment (PPE) among the quarry workers in Abia and Ebonyi State, South East Nigeria was conducted between May 2019 to June 2021 with the aim of determining the usage of personal protective equipment (PPE) among the quarry workers and to know if their level of education influences their use of PPE. Interviewing of workers with well-structured questionnaires was used for the study. The study population consists of seven registered quarries in both states. The multi-stage random sampling technique was employed in the study. The first stage was the selection of quarry sites, in which seven quarry sites were randomly selected through balloting. In the second stage, a total number of 406 quarry workers were selected for the study. Data was collected using a well-structured questionnaire. The data were analyzed using Statistical Package for Social Science (SPSS) version 20, percentages and mean were also used. Results: On the usage of personal protective equipment (PPE) by respondents, the result shows that 20.1% (49) out of 246 quarry workers in Ebonyi state use their PPE while 13.0% (21) out of 162 workers use theirs in Abia State. 61.2% (30) in Ebonyi and 7.4% (15) in Abia always used PPE regularly, 38.8% (19) and 28.6% (6) said “sometimes.” 46.9% (23) and 42.9% (9) in both states used nose masks, 22.5% (11) and 9.5% (2) helmets, 18.4% (9) and 19.1% (4) boots, glove users amounted to 8.2% (4) and 4.3% (3) in both states, 4.1% (3) and 4.3% (13) in Abia used body overall respectively. On the usage of PPE based on the level of education, it was found that among those with no formal education, 11.4% used PPE while working and 19.6% do not use it, 25.7% of those with primary education did while 48.8% did not. Among those with secondary and tertiary education 34.6% and 24.3% utilized PPE while 28.3% and 3.3% did not use PPE. This study found a statistically significant association between level of education and usage of personal protective equipment in both States (p= 0.0231). Conclusion: Information obtained from the study revealed that the majority of quarry workers in Abia and Ebonyi state knew that their job exposes them to health hazards. But there was a low turnout of usage among them. Despite these varying levels of compliance, intensive health education campaigns and provision of adequately subsidized safety protective devices for the workers by the relevant authorities will go a long way in improving awareness and compliance with use of safety protective devices and reduction of hazards.

Parameter Calibration and System Design of Material Lifting System for Inclined Shaft Construction

As a key transportation equipment in the construction of long tunnels with large slope, the material hoisting system plays an important role in the transportation of materials in sloping shafts. This paper proposes a parameterized calibration scheme for the hoisting system based on the structure and working principle of the hoisting system, taking the wire rope, hoist, motor and overhead wheel as the research objects, and according to the relevant industry specifications and numerical calculation methods. Based on the structural design and functional analysis of the hoisting system, a reasonable control system, monitoring system and safety protection devices are designed, and the calibration scheme and the designed system are introduced into the Dianzhong water diversion project for verification. The parameters of each component of the hoisting system were calculated as follows: maximum breaking tension value of wire rope 490.29 KN, drum diameter 2000 mm, motor hoisting power 213.7 KW, and the system design was as follows: control system selects frequency conversion electric control method, safety protection device selects ZDC30-2.5 anti-running device. The results show that: the hoisting system components structure parameters meet the specification requirements—safety protection devices can effectively prevent the occurrence of sports car slippage and man-car jumping rail overturning accident—to meet the requirements of the construction period transport capacity and transport safety. The relevant experience can provide the basis for the design of a material hoisting system for a similar inclined shaft construction.

Research on Key points of escalator braking Safety Performance detection method

In the rapid development of social economy and science and technology, Chinese public transportation and large-scale shopping malls, stations, airports in the construction promotion, start to use escalator in a large number, as a transportation vehicle of the new era construction development, although it has solved the problems of the human flow of the traditional urban construction and development, but also a lot of safety accidents have emerged. According to the practice investigation and research, there are many types of escalator safety accidents at home and abroad, which are reflected in the safety protection device, synchronous safety, brake safety and other aspects, which directly endanger people's life, property and health. Therefore, on the basis of understanding the theoretical research status of escalator technology, and according to the overall design of automatic safety performance detection of escalator, we propose an escalator braking performance test method, and then mainly study the safety and reliability of escalator equipment, in order to provide an effective basis for the construction and development of a new era.

Research on Standardized Management of Basic Data Elements in Integrated Management Information System

In the rapid development of social economy and science and technology, Chinese public transportation and large-scale shopping malls, stations, airports in the construction promotion, start to use escalator in a large number, as a transportation vehicle of the new era construction development, although it has solved the problems of the human flow of the traditional urban construction and development, but also a lot of safety accidents have emerged. According to the practice investigation and research, there are many types of escalator safety accidents at home and abroad, which are reflected in the safety protection device, synchronous safety, brake safety and other aspects, which directly endanger people's life, property and health. Therefore, on the basis of understanding the theoretical research status of escalator technology, and according to the overall design of automatic safety performance detection of escalator, we propose an escalator braking performance test method, and then mainly study the safety and reliability of escalator equipment, in order to provide an effective basis for the construction and development of a new era.

Research on optimization of crane fault predictive control system based on data mining

Abstract To ensure the safe functioning of lifting equipment, a data mining-based optimization study of a crane failure predictive control system is provided. To diagnose lifting machinery faults, the system employs decision tree categorization. Using association rules, a correlation study of hoisting machinery defect and failure was performed. When the minimal confidence and support degree are entered, a total of 244 instances of 18 frequent itemset A9 (safety protection device) may be obtained, indicating that lifting machinery does not perform well in this category. A6 (main parts) and A9 appeared a total of 98 times, with support and confidence of 29.4 and 35.6, respectively, indicating that the main parts can detect that the safety protection device is also having problems. A7 (electrical control system) and A9 appeared a total of 67 times, with support and confidence of 20.1 and 27.3, respectively, indicating that the electrical control system can detect that the safety protection device is also having problems; the correlation between them was also quite large. The system’s feasibility and efficacy shows that it has some application value.

Failure analysis on abnormal leakage of plastic floating ball in transformer gas relay for nuclear power plant

The plastic components are always more prone to property degradation than the conventional metallic components, so their safety reliability is paid more attention for the routine maintenance. The gas relay containing two plastic balls is an important safety protection device of the high-voltage transformer. The two plastic hollow floating balls inside the relay buoy in the insulating oil level, and float up and down with exhausting and generation of the gas and oil. Once the oil level increases or decreases beyond the safety limits, the protection switches are immediately actuated by the floating ball. In this paper, one plastic floating ball inside the relay in high-voltage transformer was found leaked during one refueling cycle of a nuclear power plant because quite a bit insulating oil was penetrated inside the ball. Although no serious consequence had been aroused, it will bring the potential safety hazards for the normal operation of the transformer. For this reason, the failure analysis was systematically performed to analyze and identify the causes of abnormal leakage of the plastic ball. The comprehensive testing and analysis results indicated that the unqualified fusion process of two plastic hemispheres was the root cause, thus the pertinent countermeasures were proposed.

Influencing factors of agricultural machinery accidents based on fuzzy fault tree analysis

Safety is an important indicator to the design of agricultural machinery products. In order to grasp the risk source of agricultural machinery accidents accurately, explore the causes and laws of agricultural machinery accidents, and prevent the occurrence of various accidents in the process of agricultural machinery products effectively. This study constructs a fuzzy fault tree model by combining the fault tree analysis method with the triangular fuzzy number, and analyzes the factors which cause agricultural machinery accidents. The results are as follows: 1) Through fault tree analysis, 23 known and potential causes of agricultural machinery accidents were deduced, and 57 minimum cut sets and 3 minimum path sets were solved; 2) The probabilities of 23 basic events were fuzzed by triangular fuzzy number theory, and the fuzzy probability value of each basic event was obtained; 3) Sorting fuzzy importance of 23 basic events has clarified the degree of influence of each basic event on the top event. Factors such as, Machine without safety protection device (X1), Personnel not wearing safety protective equipment (X2), Long Working Hours (X16), Unreasonable control device (X15), Speeding and overloading (X7), are ranked top among the 23 factors. The analysis result shows that these factors have a great impact on the occurrence of agricultural machinery accidents which should be given priority in the formulation of preventative measurements to agricultural machinery accidents.

Driver injury severity in two-vehicle accidents considering collision role

In order to study the influencing factors of driver injury severity and the interaction effects of collision roles in two-vehicle accidents, based on the data of two-vehicle collision accidents in Shenzhen from 2018 to 2020, we calculate the value of importance degree of characteristic variables by using random forest algorithm to screen out the candidate independent variables, and establish a binary logit model of driver injury severity considering collision angle. The results show that collision role, accident responsibility, vehicle type, accident form, driving experience, visibility, collision form between vehicles, educational background, road grade, use of safety protection devices, roadside protection facilities and lighting conditions are significantly associated with the driver injury severity in two-vehicle accidents. Meanwhile, there are significant interaction effects among collision role, vehicle type and accident form. The results are helpful for understanding the influence mechanism of driver injury severity in two-vehicle accidents and can help traffic management departments to formulate corresponding traffic safety countermeasures.

The Commodification of Security in Brazil: Urban–Rural Divide in Household Adoption of Safety Protective Devices

This study aims to assess the determinants of using safety devices in Brazilian households, taking into account different urban–rural country contexts and income distribution. Probit models are estimated using microdata from the 2009 Brazilian National Household Sampling Survey. On average, less than half of the underprivileged population adopts safety devices, whereas almost double as many do so among the wealthy. Findings also indicate an inverse association between the level of urbanization and adoption of safety protective devices, especially of modern ones—a pattern mediated by individual levels of victimization and safety perceptions. For example, previous victimization by theft or robbery is more decisive for adopting safety protective devices among economically underprivileged households compared to wealthier ones. These results provide evidence of the perverse effects of unequal commodification of security across a country that penalizes, in particular, the rural poor.

Development and test of hydraulic driven remote transporter

To solve the problems of the traditional orchard conveyor, such as inflexible steering, a complex structure, poor stability and no power grid coverage, a remote-controlled rail conveyor powered by hydraulic pressure for mountainous orchards was designed and manufactured. Climbing stress analysis was carried out on a full-load trailer to obtain the maximum traction force, which meets the requirement of the climbing slope of the transport mechanism. The key components of the conveyor were developed, such as the hydraulic transmission, the control system, safety protection devices, limiting devices, the throttle and decompression actuator, the counterweight tension and the battery. Through the theoretical calculations of key components, an orchard conveyor powered by diesel and hydraulic pressure was designed. Finally, the working performance of the transporter was tested through functionality, driving speed, system pressure and remote-controlled tests. The test results showed that the climbing angle of the transporter can reach 50°, the uphill load can reach 840 kg, the downhill load can reach 1100 kg, and the average running speed is 0.77 m/s; the driving speed ranges from 0.29 m/s to 1.08 m/s, and the system pressure ranges from 3.2 MPa to 10 MPa. The driving speed and system pressure are significantly affected by the load, and the remote control distance can reach 455 m. The technical specifications of the transporter meet all the design requirements, and the problem of stable operation of the transporter without power grid coverage has been addressed. The research results can well meet the practical application requirements of mountain orchard transportation without power grid coverage and provide theoretical reference for the design of key components of mountain orchard transportation machinery. Keywords: mountain orchard, conveyor, hydraulic drive, remote control DOI: 10.25165/j.ijabe.20211402.5844 Citation: Li J X, Li S J, Zhang Y L, Liu M D, Gao Z Y. Development and test of hydraulic driven remote transporter. Int J Agric & Biol Eng, 2021; 14(2): 72–80.

Application Computer Detection and Control System in Automobile Electronic Control System

The overall development of our society has promoted the development of computer technology, making the various performances of modern cars more perfect. The application of computer detection and control system technology in automobile electronic control devices can realize the intelligence and automation of automobile control. Now in the information age, computer perception and control technology are widely used in various social production fields, and are also widely used in automotive electronic control systems. Due to the emergence of automotive electronic control technology, automotive performance continues to improve, automotive safety performance improves, and automotive dynamic performance becomes stronger. In the automotive electronic control device, to understand the role of the computer detection and control system more specifically, it is necessary to fully understand and master the operation principle of the computer detection and control technology and the application range of the automotive electronic control device. In order to further improve the safety performance of the vehicle, in addition to the structural improvement of the vehicle itself and the addition of safety protection devices, it is a more effective method to perceive the surrounding environment and vehicle status during driving to achieve control. This article first introduces the computer detection and control technology, and analyzes the application program in the automotive electronic control device for reference.

3D Printed Masks for Powders and Viruses Safety Protection Using Food Grade Polymers: Empirical Tests.

The production of 3D printed safety protection devices (SPD) requires particular attention to the material selection and to the evaluation of mechanical resistance, biological safety and surface roughness related to the accumulation of bacteria and viruses. We explored the possibility to adopt additive manufacturing technologies for the production of respirator masks, responding to the sudden demand of SPDs caused by the emergency scenario of the pandemic spread of SARS-COV-2. In this study, we developed different prototypes of masks, exclusively applying basic additive manufacturing technologies like fused deposition modeling (FDM) and droplet-based precision extrusion deposition (db-PED) to common food packaging materials. We analyzed the resulting mechanical characteristics, biological safety (cell adhesion and viability), surface roughness and resistance to dissolution, before and after the cleaning and disinfection phases. We showed that masks 3D printed with home-grade printing equipment have similar performances compared to the industrial-grade ones, and furthermore we obtained a perfect face fit by customizing their shape. Finally, we developed novel approaches to the additive manufacturing post-processing phases essential to assure human safety in the production of 3D printed custom medical devices.

Development and test of hydraulic driven remote transporter

To solve the problems of the traditional orchard conveyor, such as inflexible steering, a complex structure, poor stability and no power grid coverage, a remote-controlled rail conveyor powered by hydraulic pressure for mountainous orchards was designed and manufactured. Climbing stress analysis was carried out on a full-load trailer to obtain the maximum traction force, which meets the requirement of the climbing slope of the transport mechanism. The key components of the conveyor were developed, such as the hydraulic transmission, the control system, safety protection devices, limiting devices, the throttle and decompression actuator, the counterweight tension and the battery. Through the theoretical calculations of key components, an orchard conveyor powered by diesel and hydraulic pressure was designed. Finally, the working performance of the transporter was tested through functionality, driving speed, system pressure and remote-controlled tests. The test results showed that the climbing angle of the transporter can reach 50°, the uphill load can reach 840 kg, the downhill load can reach 1100 kg, and the average running speed is 0.77 m/s; the driving speed ranges from 0.29 m/s to 1.08 m/s, and the system pressure ranges from 3.2 MPa to 10 MPa. The driving speed and system pressure are significantly affected by the load, and the remote control distance can reach 455 m. The technical specifications of the transporter meet all the design requirements, and the problem of stable operation of the transporter without power grid coverage has been addressed. The research results can well meet the practical application requirements of mountain orchard transportation without power grid coverage and provide theoretical reference for the design of key components of mountain orchard transportation machinery. Keywords: mountain orchard, conveyor, hydraulic drive, remote control DOI: 10.25165/j.ijabe.20211402.5844 Citation: Li J X, Li S J, Zhang Y L, Liu M D, Gao Z Y. Development and test of hydraulic driven remote transporter. Int J Agric & Biol Eng, 2021; 14(2): 72–80.

영상 인식 알고리즘을 이용한 안전 보호구(안전모) 탐지에 관한 연구

Safety accidents at work sites are directly related to workers" lives, and the manufacturing industry"s interest in safety accidents is increasing every year. Safety accidents at work sites are caused by a variety of factors, and it is difficult to predict when and why they occur. In this research, an intelligent image recognition-based worker safety protection device wearing algorithm that can determine suitability of wearing safety protective devices is developed and the proposed algorithm is sought to be applied to the site. In this study, the You only look once (YOLO) algorithm is applied to analyze the presence of workers wearing safety protection equipment in real time. Accuracy of object detection for safety protection equipment is very important. Thus, this study compared/analyzed the algorithms of two YOLO systems (YOLOv2, YOLOV3) and improved the performance of the model by changing Hyperparameters, Fine-tuning and Dataset of the selected algorithms. In the future, studies will be conducted on how to improve the accuracy of object detection and complement the accuracy of object detection in the proposed YOLO series algorithm.

Practical Design of Electronic Emergency Stop Devices for Machine Safety

A variety of safety protective devices (SPDs) are currently available on the machinery safety market. SPD complexity and cost depend on the safety feature implemented as required for a specific piece of machinery in its working environment. However, one type of inexpensive SPD is mandatory for many types of machines: the emergency stop device (ESD). This paper introduces a novel ESD recently developed by the authors. This electronic ESD is capable of automatically performing emergency stop actions as commanded by a suitable external supervisory safety system connected to it, which may replace or reinforce the human action expected for the provision of safety. In addition, the device allows integration with any emergency stop circuit already designed for machinery by means of configurable features. Both practical design and implementation issues are discussed in detail through a fully exemplified concept-design-prototype-validation procedure.

Design of a new type of safety protection device for gas bottle cabinet

Aiming at the problem of explosion caused by leakage of flammable and explosive gas cylinder, a new type of safety protection device for gas bottle cabinet is designed to solve this problem. The design of this new type of gas bottle cabinet safety protection device is to use GSM voice, short message control technology, sensor technology, wifi technology, plc control technology and so on, to monitor the gas in the gas bottle cabinet in real time. Once the gas in the cylinder leaks and the concentration of the leakage gas reaches the set alarm concentration, the alarm will occur, and the exhaust fan will start to discharge the leakage gas and send an alarm message to the pre-set mobile phone at the same time.

Risk-taking behaviors and exposures among vocational school students in China: a cross-sectional survey.

:Background:Injury has become the leading cause of death among adolescents. This study aimed to understand the prevalence of risk-taking behaviors and exposures and injuries among vocational school students and to provide guidance for further injury intervention. Methods:A cluster sampling method was used to conduct a questionnaire survey of all grade one and grade two students in a vocational school in Jiangsu Province in April 2018. A self-administered questionnaire was designed to investigate information on basic demographic information, risk-taking behaviors and exposures, and injuries. Results:A total of 1079 students were investigated, 490(45.41%) were boys; the mean age was 16.80±0.80 years; 560(51.90%) were grade one students. There were 57 injuries in the past 12 months. The overall injury incidence was 5.28%. The total proportions of risk behaviors ranged from 1.4% for playing on the street to 68.6% for not wearing reflective devices while walking at night. Behaviors of not using traffic safety protection devices were highly prevalent, including not using seat-belts in the back seat of cars (19.7%), not wearing helmet while taking/ riding an electric car (15.8%/13.0%), not wearing reflective devices while walking/riding at night (68.6% for pedestrians and 62.8% for two-wheelers riders). Girls generally had more negative mood exposures compared to boys. Boys generally had more traffic risk behaviors and bullying and violence experiences compared with girls. The average number of risk-taking behaviors and exposures was 8.73±8.06. The number of risk-taking behaviors and exposures was positively associated with injury, with OR of 1.07(1.04-1.10). Conclusions:Risk-taking behaviors and exposures were prevalent among vocational school students and increased the risk of injury. Traffic safety, bullying and violence, and sports safety were the aspects need more attention. The intervention of such risk behaviors should aim at the characteristics of the population and their special behavior problems.

Development of a Novel Magnetic Brake Shoe for Mine Hoists Based on Nano-Fe3O4 and Nd-Fe-B Additive.

The brake is an important safety protection device for mine hoists, in which the performance of the brake shoe affects directly the safe operation of the hoist system. In order to solve problems such as high wear rate and unstable friction coefficient of brake shoe under high temperature, this paper indicated that adding magnetic powder to the composite material of traditional mine hoist's brake shoe will be a creative and effective approach to improve its properties. Based on relevant China patents of the authors, several new formulas of brake shoe material were designed in the presence of Nano-Fe3O4 and Nd-Fe-B, and the methods of both preparation and performance testing of the magnetic brake shoes were introduced. The experiment of formula design was carried out by uniform prescription design, and the friction coefficient and wear rate of each kind of brake shoes made through different formulas were measured. Furthermore, the formula was optimized by application of fuzzy comprehensive evaluation method and analytic hierarchy process. Compared with ordinary formulas, the optimized formula is higher totally and changes more steadily as well. Its wear rate is far lower than the national standard. Namely, its comprehensive properties are better. Few relevant patents to the topic have been reviewed and cited. This paper proved that it is practically valuable and feasible to improve the properties of hoist brake shoes by adding magnetic powder to its composite material.