Influential Factors in Safety Design of Aircraft Pneumatic Duct System

The reliability and safety of the pneumatic ducts are essential for flight safety.A beam element model of the duct system is developed and the factors that impact the stress performance of the duct system are investigated,such as stress check standards,flight acceleration,internal temperature and internal pressure.The results show that the stress synthetic method as the stress check standard can obtain the more safety design results.The maximum stress of straight pipe is affected significantly by the acceleration in a plane perpendicular to straight pipe,while the maximum stress of bend pipe is greatly affected by the acceleration in the direction perpendicular to plane of the bend pipe.Meanwhile,internal pressure has little effect on the maximum stress of bend pipe and straight pipe.Temperature has little effect on the maximum stress of bend pipe while has a big impact on the maximum stress of straight pipe.

Safety Design Strategy for Highway Interchange Exit Ramp

Highway is an important type of road in China’s road network,and it also carries a larger portion of transportation task.Safety is the first indicator in the stage of its use,so it is necessary to carry out safety design focusing on the highway interchange exit ramp to effectively prevent traffic accidents.Therefore,in this paper,the important significance of the safety design of the highway interchange exit ramp and the key factors affecting its safety were discussed and studied in detail,and finally corresponding strategies were proposed for discussion and communication.

Research on the Optimization Design of Intersections for Safe Operation of Large Trucks

When big trucks are running at urban road intersections,they are easy to interfere with other motor vehicles,and the turning big trucks are easy to have conflicts with non-motor vehicles and pedestrians,which will affect the safety of intersections.This paper first studied the intersection of trucks to the running trajectory,on this basis,through the establishment of mathematical model analysis of large truck steering conditions inside the wheel,and the influence of blind area to the driver.In the research of intersection safety design,the safety design is divided into three parts:Entrance road,internal operation and signal control.At the same time,the design method of the entrance road,the interior of the intersection and the signal control is given,which improves the safety of the truck driving at the intersection.Finally,the intersection of Jungong road and Zhoujiazui road in Yangpu district of Shanghai was selected as a case,and the optimal design of the intersection for large trucks was carried out through the investigation and analysis of actual data.The evaluation and analysis were carried out by using the multi-index matter-element model.The results show that the comprehensive safety correlation degree of the intersection is reduced to 0.42,and the safety level of is improved by one level.

Design and operation problems related to water curtain system forunderground water-sealed oil storage caverns

The underground water-sealed storage technique is critically important and generally accepted for the national energy strategy in China. Although several small underground water-sealed oil storage caverns have been built in China since the 1970s, there is still a lack of experience for large-volume underground storage in complicated geological conditions. The current design concept of water curtain system and the technical instruction for system operation have limitations in maintaining the stability of surrounding rock mass during the construction of the main storage caverns, as well as the long-term stability. Although several large-scale underground oil storage projects are under construction at present in China, the design concepts and construction methods, especially for the water curtain system, are mainly based on the ideal porosity medium flow theory and the experiences gained from the similar projects overseas. The storage projects currently constructed in China have the specific features such as huge scale, large depth, multiple-level arrangement, high seepage pressure, complicated geological conditions, and high in situ stresses, which are the challenging issues for the stability of the storage caverns. Based on years’ experiences obtained from the first large-scale （millions of cubic meters） underground water-sealed oil storage project in China, some design and operation problems related to water curtain system during project construction are discussed. The drawbacks and merits of the water curtain system are also presented. As an example, the conventional concept of “filling joints with water” is widely used in many cases, as a basic concept for the design of the water curtain system, but it is immature. In this paper, the advantages and disadvantages of the conventional concept are pointed out, with respect to the long-term stability as well as the safety of construction of storage caverns. Finally, new concepts and principles for design and construction of the underground water-sealed oil storage caverns are proposed.

Lithium slurry flow cell,a promising device for the future energy storage

Lithium slurry flow cell(LSFC)is a novel energy storage device that combines the concept of both lithium ion batteries(LIBs)and flow batteries(FBs).Although it is hoped to inherit the advantages of both LIBs and FBs,such as high energy density,ease of fabrication,environmental friendly,independent energy and power density,to name but a few.While unfortunately,it still has many challenges to overcome before it becoming the future star in energy storage area.Here in this paper,we briefly recall its history and try to illustrate the main issues that hindering its research as well as application.As a typical interdisciplinary product,LSFC is definitely a promising candidate for large scale energy storage application,while obviously it still has a long way to go.

小卫星总体研制阶段安全性设计与验证分析

A safety design applies to every stage in a satellite system development life cycle to identify and analyze hazards in the satellite at a system level, eliminating or controlling various safety risks, while verifying the functions of the satellite system have safety characteristics, so as to optimize the satellite system for the best performance in terms of time and cost. This article comprehensively leverages such factors as satellite reliability, complexity and life cycle by considering the overall satellite safety work plan, hazard analysis, hazard sources, pyrotechnic devices and other module safety critical designs. Safety design measures were formulated to review and verify the effectiveness of system functions including a safe power supply to a satellite and pyrotechnic explosives to achieve the safety requirements of the satellite from a development stage. Safety design activities for each subsystem will ensure meeting the development requirements of the satellite system as a whole, and ensure the satellite system cannot be the cause of casualties, equipment damage, property loss, or have a health-threatening impact or detrimental impact on the environment.

Influence of geometric design characteristics on safety under heterogeneous traffic flow

This paper focuses on analysing the influence of geometric design characteristics on traffic safety using bi-directional data on a divided roadway operated under heterogeneous traffic conditions in India. The study was carried out on a four lane divided inter-city highway in plain and rolling terrain. Statistical modelling approach by Poisson regression and Negative binomial regression were used to assess the safety performance as occurrence of crashes are random events and to identify the influence of the geometric design variables on the crash frequency. Negative binomial regression model was found to be more suitable to identify the variables contributing to road crashes. The study enabled better understanding of the factors related to road geometrics that influence road crash frequency. The study also established that operating speed has a significant contribution to the total number of crashes. Negative binomial models are found to be appropriate to predict road crashes on divided roadways under heterogeneous traffic conditions.

Call For Paper 5th International Maritime Conference on DESIGN FOR SAFETY and 4th Workshop on RISK-BASED APPROACHES IN THE MARINE INDUSTRIES

In 1999, the first International Maritime Confere- nce on Design for Safety was successfully held in Glasgow, UK as a WEGEMT Euro Conference with the sponsorship of the European Commission. Respo- nding to the expectation from the world maritime safety community, the second was held in 2004 in Japan. The third and fourth were held in USA, 2007 and Italy, 2010, respectively. This year the Design for Safety conference including a single event of the 4th Workshop on Risk-Based Approaches in the Marine Industries will be held in Shanghai on November 25- 27, 2013. The conference is organized by Shanghai Jiao Tong University and is co-organized/sponsored by Marine Design and Research Institute of China （MARIC） and China Classification Society （CCS~.

A Hazard Analysis-based Approach to Improve the Landing Safety of a BWB Remotely Piloted Vehicle

The BUAA-BWB remotely piloted vehicle （RPV） designed by our research team encountered an unexpected landing safety problem in flight tests. It has obviously affected further research project for blended-wing-body （BWB） aircraft configuration characteristics. Searching for a safety improvement is an urgent requirement in the development work of the RPV. In view of the vehicle characteristics, a new systemic method called system-theoretic process analysis （STPA） has been tentatively applied to the hazardous factor analysis of the RPV flight test. An uncontrolled system behavior ＂path sagging phenomenon＂ is identified by implementing a three degrees of freedom simulation based on wind tunnel test data and establishing landing safety system dynamics archetype. To obtain higher safety design effectiveness and considering safety design precedence, a longitudinal ＂belly-flap＂ control surface is innovatively introduced and designed to eliminate hazards in landing. Finally, flight tests show that the unsafe factor has been correctly identified and the landing safety has been efficiently improved.

Discussing the development of domestic and foreign fire protection technical regulation and fire protection technical standard systems

This paper reviews the composition, development, and operation mechanism of domestic and foreign fire protection technical regulations and standards. Considering the development and problems of China's fire protection standard system and fire protection technical standards, this paper recommends fire safety professional engineering design specialization, suggests key research fields pertaining to fire protection technical standards, and elucidates how a performance-based fire protection technical standard system can be established.

Controlling Town Industry Explosion Hazard in China

This article introduces industrial safety issues encountered in the towns of China,points out the importance of damage control of industrial explosions and disaster management,and puts forward suggestions on safety design and management intended to reduce the frequency and impact of industrial explosions in Chinese town areas.

Pulsed actuation avoids failure in dielectric elastomer artificial muscles

Dielectric elastomer actuators(DEAs)are a class of artificial muscles capable of large linear strains(well over 100%),and with high energy density,and low cost and weight.One of the most prominent failure modes of a DEA is electrical breakdown,which can damage the device permanently,limiting its deformation capability.Breakdown is also common,since to maximize energy output,devices often operate near the breakdown limit.Elucidating breakdown mechanisms,as well as finding ways to prevent it,are of intense research interest.We show that by applying short electrical pulses,one could minimize the exposure of the DEAs to high leakage current,which is one of the main mechanisms for electrical breakdown.This allows one to operate at significantly higher potentials than the DC breakdown voltage.By applying pulses,we demonstrate up to 81.7%area strain repeatedly,at voltages more than twice the DC breakdown limit,without the risk of failure.The pulsed operation mode of DEAs accommodating higher voltages than possible with DC represents an opportunity for potential applications,safer and simpler device designs,and a technique for further study of DEA breakdown mechanisms.