基于STM32的石油管材测厚系统设计

针对现有石油管材检测存在的不足,设计了一种石油管材实时检测与数据处理的智能测厚系统。该系统以STM32为主控芯片,以TDC-GP22为采集芯片经过计算得到管道厚度,以I2C总线方式实现主从机通信,以HLK-RM04嵌入式模块实现与上位机应用软件的数据传输与采集功能,同时配合控制多个42步进电机与直流喷液电机实现运动、耦合、温湿度检测等功能,给出了硬件部分与上位机软件的设计与实现。与传统的人工作业效率相比,大大提升了安全系数、工作效率。     

Foreign exchange markets and oil prices in Asia

In this paper, we examine whether oil price can predict exchange rate returns for 14 Asian countries. A new GLS-based time series predictive regression model proposed by Westerlund and Narayan (WN, 2012) is used. The main finding is that higher oil price leads to future depreciation of the Vietnamese dong but future appreciations of the local currencies of Bangladesh, Cambodia, and Hong Kong. A comparison of the widely used Lewellen (2004) and WN (2012) estimators show that both provide similar results in in-sample analysis, although WN is relatively superior at longer horizons in out-of-sample analysis.     

Quantification of the high level of endogeneity and of structural regime shifts in commodity markets

We propose a “reflexivity” index that quantifies the relative importance of short-term endogeneity for several commodity futures markets (corn, oil, soybean, sugar, and wheat) and a benchmark equity futures market (E-mini S&P 500), from mid-2000s to October 2012. Our reflexivity index is defined as the average ratio of the number of price moves that are due to endogenous interactions to the total number of all price changes, which also include exogenous events. It is obtained by calibrating the Hawkes self-excited conditional Poisson model on time series of price changes. The Hawkes model accounts simultaneously for the co-existence and interplay between the exogenous impact of news and the endogenous mechanism by which past price changes may influence future price changes. Our robustness tests show that our index provides a ‘pure’ measure of endogeneity that is independent of the rate of activity, order size, volume or volatility. We find an overall increase of the reflexivity index since the mid-2000s to October 2012, which implies that at least 60–70 percent of commodity price changes are now due to self-generated activities rather than novel information, compared to 20–30 percent earlier. While our reflexivity index is defined on short-time windows (10–30 min) and thus does not capture long-term memory, we discover striking coincidence between its dynamics and that of the price hikes and abrupt falls that developed since 2006 and culminated in early 2009.     

中哈原油管道两国计量输差数学模型分析

用流体的连续性方程并结合质量守恒定律对中哈管道阿塔苏站-阿拉山口站的参数进行分析后建立了计量输差的数学模型关系,通过数据验证了该模型。结果说明两国之间毛重计量输差的主要影响因子是输送过程中两站间管道中油品密度变化率,从而为解决两国间流量计计量数据争议提供了重要参考。     

A MILP model for planning the trips of dynamic positioned tankers with variable travel time

The transportation of the crude oil produced in offshore oilfields to onshore terminals is performed by vessels, known as shuttle tankers. Scheduling shuttle-tanker operations entails solving complex problems to ensure a timely offloading of the platforms, taking into account several logistics and inventory constraints. This work proposes a new MILP formulation that advances previous works by considering variable travel time between platforms and terminals. The combination of the MILP formulation with an optimization solver constitutes a decision-support tool to aid engineers reach optimal decisions for a planning horizon. To handle large-scale instances, rolling-horizon and relax-and-fix strategies are proposed.     

Oil price dynamics and airline earnings predictability

This study examines the effect of oil price dynamics on quarterly earnings and their predictability with a sample of 30 airlines for 1994–2017. First, we document a significantly positive impact of demand-driven oil shocks on airline earnings, suggesting that the revenue effect from shifting air travel demands dominates the cost effect of aviation fuels. Regarding earnings predictability, we find evidence of deterioration in oil-volatile quarters as indicated by both the earnings variability based on common benchmarks and the quality of analyst forecasts issued early in the quarter. We further show that supply-driven oil shocks have a more detrimental impact on earning predictability than demand-driven oil shocks. Finally, we do not find supporting evidence for the possible moderating effect of hedging.     

Entrepreneurial rents and the theory of the firm

The creation of entrepreneurial rents occurs under conditions of uncertainty. Yet current theories of rent appropriation such as transactions cost theories of the firm focus their efforts primarily on how quasi-rents – rents that have already been created – are appropriated by parties to that exchange. Entrepreneurs face a dual challenge, that of creating entrepreneurial rents and appropriating some of these rents. Moreover, this challenge usually exists at a time when the entrepreneurial rents that might be created are not known or anticipatable. Indeed, entrepreneurs not only concern themselves with ensuring that they are able to appropriate at least some of the rents that might be eventually created but in fact they may not create any rents or potentially lose value. Understanding the dual nature of the rent creation and the rent appropriation problem has a variety of implications for the study of entrepreneurial organizations and generally for theory of the firm discussions.     

罐存藤椒油全年品质变化规律的研究

通过测定储存在涂防晒涂料罐体中的藤椒油感官、酸值和过氧化值等指标,掌握存油品质变化规律。结果表明:藤椒油储存过程中香麻味先逐步减弱后麻度开始降低,麻度降低的过程中酸值、过氧化值升高,在1 a罐存期内各项检测指标均符合《绿色食品调味油》(NY/T2111-2011)标准中规定。     

我国石油对外贸易流量分析与对策研究

石油是关系国家经济安全的重要战略物资,本文通过对我国石油进出口贸易一些流量指标的分析,发现:(1)石油净进口量过大,进口依存度偏高,并有逐年递增的趋势;(2)原油进口的地区集中度偏高,不利于石油资源供应稳定;(3)国际油价持续高企,对国内经济稳定造成威胁。并据此提出了相关政策建议。     

不同萃取试剂检测羽绒残脂率的差异性分析

选用乙醚、二氯甲烷和石油醚作为羽绒残脂率的萃取试剂,对3种试剂检测结果进行了比对分析。结果显示：二氯甲烷检测结果高于乙醚的检测结果,而石油醚的检测结果低于乙醚的检测结果。从统计学角度分析得出这两种试剂的检测结果与乙醚的检测结果都存在显著性差异,二氯甲烷和石油醚无法直接作为乙醚萃取的替代性试剂。