System Safety Management of Whole Life Cycle of Chemical Process Unit

Guaranteeing the safety performance of chemical process units is the premise for the safety production of chemical enterprises.Only to have the system safety management of the whole life cycle of the process units can operate the process systems under the state of controllable risk.

Distribution Network Equipment Location and Capacity Planning Method Considering Energy Internet Attribute from the Perspective of Life Cycle Cost

For facing the challenges brought by large-scale renewable energy having access to the system and considering the key technologies of energy Internet,it is very necessary to put forward the location method of distribution network equipment and capacity from the perspective of life cycle cost.Compared with the traditional energy network,the equipment capacity problem of energy interconnected distribution network which involves in electricity network,thermal energy network and natural gas network is comprehensively considered in this paper.On this basis,firstly,the operation architecture of energy interconnected distribution network is designed.Secondly,taking the grid connection location and configuration capacity of key equipment in the system as the control variables and the operation cost of system comprehensive planning in the whole life cycle as the goal,the equipment location and capacity optimization model of energy interconnected distribution network is established.Finally,an IEEE 33 bus energy mutual distribution grid system is taken for example analysis,and the improved chaotic particle swarmoptimization algorithm is used to solve it.The simulation results show that the method proposed in this paper is suitable for the equipment location and capacity planning of energy interconnected distribution network,and it can effectively improve the social and economic benefits of system operation.

THM coupled analysis of cement sheath integrity considering well

he cement sheath is the heart of any oil or gas well for providing zonal isolation and well integrity during the life of a well.Loads induced by well construction operations and borehole pressure and temperature changes may lead to the ultimate failure of cement sheath.This paper quantifies the potential of cement failure under mechanically and thermally induced stress during the life-of-well using a coupled thermalehydrologicalemechanical(THM)modeling approach.A staged finite-element procedure is presented considering sequential stress and displacement development during each stage of the well life,including drilling,casing,cementing,completion,production,and injection.The staged model quantifies the stress states and state variables,e.g.,plastic strain,damage,and debonding at cement/rock or cement/casing interface,in each well stage from simultaneous action of in-situ stress,pore pressure,temperature,casing pressure,and cement hardening/shrinkage.Thus,it eliminates the need to guess the initial stress and strain state before modeling a specific stage.Moreover,coupled THM capabilities of the model ensure the full consideration of the interaction between these influential factors.

Research on the security of China's oil resources supply based on the objective weight method

With the rapid development of China's economy,external dependence on petroleum resources continues to increase,and their security has become an important part of national security.To evaluate the security of China's petroleum resource supply in a scientific and objective manner,this study establishes a corresponding petroleum life-cycle evaluation index system,based on the theory and method of the whole life-cycle security evaluation of mineral resources,and conducts further independence and grey correlation analysis on the indexes for the purpose of evaluating the petroleum risk situation in China,based on relevant public data from the past 10 years.The results show that the overall trend of China's oil risk has a“U”-shaped characteristic of first decreasing and then increasing.Furthermore,the analysis finds that China's mineral resources have been greatly influenced by the domestic production situation and international trade.These results suggest that the security of petroleum supply can be improved by safeguarding international trade in petroleum resources,strengthening the strategic reserves of domestic petroleum resources,and developing new alternative clean energy sources to improve the resilience of petroleum supply security.This study's research methodology is more logical and systematic than traditional methods,and the analysis of the factors is comprehensive and of high application value,providing implications for the establishment of a big data analysis and evaluation index system for oil resource security.

Dendrite-accelerated thermal runaway mechanisms of lithium metal pouch batteries

High-energy-density lithium metal batteries(LMBs)are widely accepted as promising next-generation energy storage systems.However,the safety features of practical LMBs are rarely explored quantitatively.Herein,the thermal runaway behaviors of a 3.26 Ah(343 Wh kg^(−1))Li|LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2)pouch cell in the whole life cycle are quantitatively investigated by extended volume-accelerating rate calorimetry and differential scanning calorimetry.By thermal failure analyses on pristine cell with fresh Li metal,activated cell with once plated dendrites,and 20-cycled cell with large quantities of dendrites and dead Li,dendrite-accelerated thermal runaway mechanisms including reaction sequence and heat release contribution are reached.Suppressing dendrite growth and reducing the reactivity between Li metal anode and electrolyte at high temperature are effective strategies to enhance the safety performance of LMBs.These findings can largely enhance the understanding on the thermal runaway behaviors of Li metal pouch cells in practical working conditions.

Research on Application＇s Credibility Verification Based on ABD

Software credibility refers to the matching degree between the expected result and system behavior in the real running environment. This paper focuses on the application of software creditability verification method based on the application behavior declaration （ABD）, in which the application of software credibility validation process and the software behavior declaration definition statement are put forward. In the integration of the process and the software development life cycle, the ABD is embedded into the software development phases to make the software behavior be consistent with the judgment and the final realization meet the requirement of trusted software verification.