A STAMP-Game model for accident analysis in oil and gas industry

Accidents in engineered systems are usually generated by complex socio-technical factors.It is beneficial to investigate the increasing complexity and coupling of these factors from the perspective of system safety.Based on system and control theories,System-Theoretic Accident Model and Processes(STAMP)is a widely recognized approach for accident analysis.In this paper,we propose a STAMP-Game model to analyze accidents in oil and gas storage and transportation systems.Stakeholders in accident analysis by STAMP can be regarded as players of a game.Game theory can,thus,be adopted in accident analysis to depict the competition and cooperation between stakeholders.Subsequently,we established a game model to study the strategies of both supervisory and supervised entities.The obtained results demonstrate that the proposed game model allows for identifying the effectiveness deficiency of the supervisory entity,and the safety and protection altitudes of the supervised entity.The STAMP-Game model can generate quantitative parameters for supporting the behavior and strategy selections of the supervisory and supervised entities.The quantitative data obtained can be used to guide the safety improvement,to reduce the costs of safety regulation violation and accident risk.

Stress release mechanism of deep bottom hole rock by ultra-high-pressure water jet slotting

To solve the problems of rock strength increase caused by high in-situ stress,the stress release method with rock slot in the bottom hole by an ultra-high-pressure water jet is proposed.The stress conditions of bottom hole rock,before and after slotting are analyzed and the stress release mechanism of slotting is clarified.The results show that the stress release by slotting is due to the coupling of three factors:the relief of horizontal stress,the stress concentration zone distancing away from the cutting face,and the increase of pore pressure caused by rock mass expansion;The stress concentration increases the effective stress of rock along the radial distance from O.6R to 1R(R is the radius of the well),and the presence of groove completely releases the stress,it also allows the stress concentration zone to be pushed away from the cutting face,while significantly lowering the value of stresses in the area the drilling bit acting,the maximum stress release efficiency can reach 80%.The effect of slotting characteristics on release efficiency is obvious when the groove location is near the borehole wall.With the increase of groove depth,the stress release efficiency is significantly increased,and the release range of effective stress is enlarged along the axial direction.Therefore,the stress release method and results of simulations in this paper have a guiding significance for best-improving rock-breaking efficiency and further understanding the technique.

Prognostics and Remaining Useful Life Prediction of Machinery:Advances,Opportunities,and Challenges

As the fundamental and key technique to ensure the safe and reliable operation of vital systems,prognostics with an emphasis on the remaining useful life(RUL)prediction has attracted great attention in the last decades.In this paper,we briefly discuss the general idea and advances of various prognostics and RUL prediction methods for machinery,mainly including data-driven methods,physics-based methods,hybrid methods,etc.Based on the observations fromthe state of the art,we provide comprehensive discussions on the possible opportunities and challenges of prognostics and RUL prediction of machinery so as to steer the future development.

长江三峡库区地质灾害遥感图像信息处理及其监测和评估

长江三峡作为世界上最大的水利工程,引起了世界的广泛关注。水库堤岸的长度、水库容载力、三峡移民数量以及其对生态环境的影响都成为议论的焦点。最引人注目的是长江两岸存在大量的地质灾害,如:滑坡、崩塌等,其中有些大型灾害体目前仍处于活动状态,这将给三峡工程的安全与库岸稳定性以及库区生态环境带来深远的影响。因此,采用3S和多时相TM、SPOT、ERS-SAR和RADARSAT等图像集成新技术来快速有效地监测、研究和评估地质灾害对三峡工程以及周边环境的影响,为地质灾害的预防和治理提供科学依据,本成果具有重要的学术意义和实用价值。

应用多种数据融合方法对多时相SPOT图像处理提取三峡工程大坝区地面动态变化信息(英文)

三峡库区三斗坪大坝区及其周围地区在1994到1998年期间,由于大坝的施工地面发生了巨大变化。这些变化在1990、1997和1998年获取的SPOT遥感图像上都有明显的记录,其中一些地面变化细节在分辨率10m的全波段(P)图像更为清楚。这里利用三种方法(高通滤波算法[2](HPFalgorithm,Chavezetal.1991)、RWM-ARSIS方法(RanchinandWald,1999)和P+XS算法[1](Anonymous1986))对三峡工程三斗坪大坝区的多时相高空间分辨率的SPOT图像(获取时间为1990,1997和1998年,包括全波段P图像和多波段XS图像)进行融合处理,在提取测区地面动态变化信息的同时,从理论和实际应用的角度探讨了不同数据融合方法的效果。

层状岩体边坡参数对破坏面形状的影响(英文)

本文根据文献(1)中层状岩体边坡最危险组合滑面的确定方法,编制了计算程序 JCIRCLE,通过算例对边坡和结构面的几何参数和力学参数等对滑面形状的影响进行了讨论。

复杂介质下保真振幅Kirchhoff深度偏移

本文详细讨论地下复杂介质地震成像问题.当速度模型含有强横向变化时,射线场会折叠形成多次走时,在这种情况下,文中证明在保真振幅叠前深度偏移时,应当考虑所有的到时才能得到定量的像.通过实例证明,在多次走时情况下,常规的共炮集、共检波器集都存在强的假像;由此提出共角度偏移的概念.最后,在多次走时下,讨论多次偏移算子(走时、相移、振幅等)的高效重构,给出了三维叠前深度偏移的快速算法.

Mountain Water Tower and Ecological Risk Estimation of the Mesta-Nestos Transboundary River Basin (Bulgaria-Greece)

The Mesta-Nestos river basin in Bulgaria and Greece is a case study for transboundary decision-making support in south-eastern Europe and a show-case for the development of methodologies and information-gathering for the integrated regional planning of water resources. Land-use conflicts in this water-scarce region cover a wide spectrum of activities like agricultural irrigation, drinking water production, diversions for industrial water, and risk of pollution from mining, to name a few examples. Measurements of the water quality were carried out in the upper basin. Results will be illustrated by the example of the environmental situation in the alpine region of the Pirin National Park as well as in the Razlog Basin with a stronger anthropogenic impact and pollution around a former uranium mine near the village of Elesnica. The social and economic development of this transboundary region is a recently established priority for mean an increase in water usage the water resources if regional the future. It will and more stress for impacts of global climate change are verified. Problem-focused management of the catchment area as a whole on the basis of proved geo-data sets is needed for the future.

Characterization of a 3-Phase a.c. Free Burning Arc Plasma

A 3-phase a.c. arc plasma reactor with large volume plasma has been developed for the synthesis of new carbon nano-structures. One of the main characteristics of the plasma system is related to the absence of a fixed neutral point. This gives rise to a rich and complex phenomenology related to instabilities and arc motion since the arcs are ＂burning＂ freely in the gas flow between the three electrodes. This paper is dedicated to the analysis of the behavior of such a system under typical conditions using argon and nitrogen as plasma gases. A classification of are configuration, arc commutating, arc interaction, arc motion and arc instabilities are discussed based on ultra high-speed cine camera analysis. A simple model describing the time evolution of the system is also presented and compared with the experimental measurements. The results show that an adequate control could allow the improvement of the overall system.

Needs of thermodynamic properties measurements and modeling in the frame of new regulations on refrigerants

In 1987, the Montreal Protocol prohibited the worldwide use and production of chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) and hydro fluorocarbons (HFCs) were proposed as alternative refrigerants. Unfortunately, HFCs have non negligible global warning potential and therefore new refrigerants must be proposed or old refrigerants must be used associated with HFC. Accurate experimental thermodynamic data and predictive techniques are required for better under-standing of the performance of the newly proposed refrigerants. In this communication, experimental techniques based on either analytic or synthetic methods are first described. Data are reported. Then two newly developed predictive models based on thermodynamic approach with the isofugacity criterion and artificial neural network method are presented. The results can provide better evaluation of refrigerants, especially with the aim of studying global warning effects.

GENERALIZATION OF THE INTERACTION BETWEEN HAAR APPROXIMATION AND POLYNOMIAL OPERATORS TO HIGHER ORDER METHODS

In applications it is useful to compute the local average empirical statistics on u. A very simple relation exists when of a function f（u） of an input u from the local averages are given by a Haar approximation. The question is to know if it holds for higher order approximation methods. To do so, it is necessary to use approximate product operators defined over linear approximation spaces. These products are characterized by a Strang and Fix like condition. An explicit construction of these product operators is exhibited for piecewise polynomial functions, using Hermite interpolation. The averaging relation which holds for the Haar approximation is then recovered when the product is defined by a two point Hermite interpolation.

Is China a Weibo Democracy？

According to North, Wallis and Weingast＇s （NWW, 2009） conceptual framework, China＇s transition to the market economy can be analyzed as a mature natural state evolving towards an open access order. The paper briefly sums up the general concepts of this theory and their adaptation to the historical conditions of the Chinese ＂Socialist Market Economy＂. It then shows that while the doorstep conditions to such an opening are put together, the route followed by the creation of market and the access to property of a 1.3 billion population is highly specific. In particular, the urbanization policy granting the ownership of housing to several hundred million of individual citizens creates unprecedented institutional needs. In this context, we suggest that rather than introducing formal political competition within the State, the monitoring of the policy through the digital social networks, and notably through the information exchanged by the 500 million of Weibo users, can provide useful and efficient guidance. In others words, that in a country with little rule of law tradition, Weibo sustains the emergence of an active civil society creating a new path to an open access order.

Evaluation of Thermal Effect of PCM Wallboards by Coupling Simplified Phase Change Model with Design Tool

A simplified PCM wallboard model is coupled to an existing design-oriented model of multi-zone buildings. Using a reference model and a basic simulation configuration, the accuracy of the resulting PCM wallboard-building thermal design tool is evaluated. A new performance indicator, called PCM utilization factor, is then proposed in order to estimate the thermal efficiency of using PCM wallboards in buildings. Using this PCM Utilization factor and a degrees-hours indicator, the ability of the PCM wallboard-building thermal design tool to evaluate the effect of PCM wallboards on heating loads and summer thermal comfort in the early design phase of a project is examined in two real case studies: a family house project and an existing office building. The user-friendliness of this design tool, and the short calculation times it leads to when performing a year-long simulation using a standard office computer, make it a well-adapted tool for sensibility studies or multi-criterion optimization for buildings that contain PCM wallboards.

2-Dimensional FEM modeling of macrosegregation in the directional solidification with mesh adaptation

In order to improve the prediction accuracy of macrosegregation channel, an algorithm for dynamic remeshing is proposed. The basic idea is to generate fine elements near the liquidus isotherm. The norm of the gradient of solid fraction is used for piloting the remeshing in the mushy zone; whereas, the objective mesh size in the liquid is considered as a function of the distance to the liquidus isotherm. The efficiency of mesh adaptation is demonstrated by prediction of macrosegregation channel in a case of unidirectional solidification.

The Lines of Lyman and the Titus-Bode Law Preferred Orbital of a Celestial Body

We have proposed, thanks to a new model of the hydrogen atom [1], some explanation of the lines observed by Lyman in the spectrographic analysis of this atom. The model is based on a prequantum physics, itself founded on classical mechanics completed by the existence of a universal cloud of tiny particles called U. This cloud induces simultaneously and similarly electromagnetic and gravitational effects. This common origin creates a narrow link between how planets are arranged in a solar system, say the Titus-Bode law, and how the electrons are arranged in an atom, say the lines of Lyman. We describe what this link is in the following text and, more generally, what is the preferred orbit of an isolated celestial body.

Evaluation of Groundwater Suitability for Domestic and Irrigational Purposes:A Case Study from Mingoa River Basin,Yaounde,Cameroon

A baseline study involving analyses of subsurface water samples from the Mingoa river basin (longitude: 11°30′E;latitude: 3°52′N) in migmatitic complex in Yaounde Cameroon (central Africa) was carried out to assess their suitability for drinking, domestic and agricultural purposes. Study results show that pH is ranged between 5.1≤ pH ≤ 5.8 and then, induces acidic waters. Groundwater samples are generally characterized by low conductivity values, of which 100% are within the range (55 ≤ EC ≤ 1500 μS/cm). The mean values of the major cations (Ca2+, Mg2+, Na+, K+) and anions (SO42– , Cl–, HCO3– ) are all within the World Health Organization (WHO) standards. Two of the springs sampled have nitrate (NO3– ) contamination. Even though contamination and acidic waters exist in some of the springs, the majority of the springs are excellent for agricultural and domestic purposes. Assessment of the groundwater for agricultural irrigation revealed two main categories. These are low salinity-low sodicity (C1-S1) and medium salinity-low sodicity (C2-S1), using the US Salinity Laboratory (USSL) classification scheme. As much as all of the samples plotted in the “excellent to good” and “good to permissible” categories on the Wilcox diagram. The groundwater in the study area may therefore be regarded as good for irrigation activities. The major identifiable geochemical processes responsible for the evolution of the various ions are mineral weathering, chemical reactions and anthropogenic activities.

Three-dimensional finite element analysis of shallow indentation of rough strain-hardening surface

Three-dimensional finite element modeling of the contact between a rigid spherical indenter and a rough surface is presented when considering both the loading and unloading phases. The relationships among the indentation load, displacement, contact area, and mean contact pressure for both loading and unloading are established through a curve fitting using sigmoid logistic and power law functions. The contact load is proportional to the contact area, and the mean contact pressure is related to the characteristic stress, which is dependent on the material properties. The residual displacement is proportional to the maximum indentation displacement. A proportional relationship also exists for plastically dissipated energy and work conducted during loading. The surface roughness results in an effective elastic modulus calculated from an initial unloading stiffness several times larger than the true value of elastic modulus. Nonetheless, the calculated modulus under a shallow spherical indentation can still be applied for a relative comparison.

Parity violation in chiral structure creation under femtosecond laser irradiation in silica glass?

The paper addresses the creation of circular optical properties from a femtosecond laser light beam with a linear polarization in an achiral material(glass)under an orthogonal incidence.In this situation,all aspects of the experiment are achiral and therefore should not give rise to chiral property creation.From that observation,we propose an interpretation that involves the action of a light-induced torque on the matter carrying a light-induced dielectric moment.We found that a direct current(DC)electric field could be produced in the lattice by the femtosecond laser in our conditions and that a non-collinear dielectric moment is created by a nonlinear effect between the DC electric field and the stress field due to the transformation of the material.We reveal that it is possible to break the chiral symmetry of glass using an intense,ultrashort laser light pulse.

Identifiability and Stability of an Inverse Problem Involving a Fredholm Equation

The authors study a linear inverse problem with a biological interpretation,which is modelled by a Fredholm integral equation of the first kind, where the kernel is represented by step functions. Based on different assumptions, identifiability, stability and reconstruction results are obtained.

一种改进零件最终力学性能的方法

工业零件的热加工，需特别注意零件的最终力学性能的改进。将组织分析模拟和成形过程模拟两者结合到一起是解决该问题的一个比较好的方法。某些机械信息如：残余应力、晶粒流向．损伤，完全可以从一种模拟转变成另外一种模拟，以便使零件的力学性能达到最优化。考虑零件疲劳性能因素，发展出了独特的疲劳模型以处理残余应力或晶粒流向。