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161.
建立考虑启动压力的低渗透数学模型,计算出无因次采油采液指数和含水率关系曲线,应用于实际区块中,分析其开发效果。结果表明:低渗透油藏考虑启动压力采液指数,甚至部分低渗透油藏在中高含水期(含水大于50%)具有一定的提液潜力。低渗透油藏无因次采液指数分为两类:第一类无因次采液指数随含水率的上升而递减,在含水率超过40%后变得平缓;第二类无因次采液指数随含水率的上升先减小而后又略有增大。 相似文献
162.
Rope shovels are used to dig and load materials in surface mines. One of the main factors that influence the production rate and energy consumption of rope shovels is the performance of the operator. This paper presents a method for evaluating rope shovel operators using the Multi-Attribute Decision-Making (MADM) model. Data used in this research were collected from an operating surface coal mine in the southern United States. The MADM model consists of attributes, their weights of importance, and alternatives. Shovel operators are considered the alternatives. The energy consumption model was developed with multiple regression analysis, and its variables were included in the MADM model as attributes. Preferences with respect to min/max of the defined attributes were obtained with multi-objective optimization. Multi-objective optimization was conducted with the overall goal of minimizing energy consumption and maximizing production rate. Weights of importance of the attributes were determined by the Analytical Hierarchy Process (AHP). The overall evaluation of operators was performed by one of the MADM models, i.e., PROMETHEE II. The research results presented here may be used by mining professionals to help evaluate the performance of rope shovel operators in surface mining. 相似文献
163.
淮扬饮食文化景观谱系的构建是深度挖掘整理淮扬菜文化基因,形成系统保护与传承体系的基础性工作.在对旅游景观谱系相关研究进行系统梳理的基础上,将饮食文化景观谱系的结构分为景观元、景观点和景观走廊三个层次,结合文献分析和专家意见,构建淮扬饮食文化景观谱系.淮扬饮食文化景观谱系对促进城市旅游资源的深度开发、促进旅游产品内涵拓展具有重要作用,对推进城市旅游转型和推广城市旅游形象等方面也具有重要的价值. 相似文献
164.
阴学军 《江汉石油职工大学学报》2012,25(1):71-72
在油田进一步推进学习型党组织建设的进程中,要通过明确学习目标,采取正确的学习方式方法,并与实践工作紧密结合,从而解决生产一线单位学习动力不足、工学矛盾突出、学以致用不够等问题。 相似文献
165.
习家口油田单井管线腐蚀严重,经常发生管线穿口事故。由于伴生气量少,翻斗计量工艺无法运行。针对这种情况采用流量计计井口计量和树杖状串联常温集输工艺,降低了能耗,避免了运输油过程中的烃类气体的排放,减少了环境污染。据统计,习家口油田年减少烃类气体挥发100万方左右,生产运行费用大幅降低,取得了较好的经济效益。 相似文献
166.
高明 《江汉石油职工大学学报》2012,(6):41-44
王场油田是江汉油田的主力油区,在进入中后期开发过程中,油层出砂日趋严重。为解决防、治砂难度大的生产问题,对王场油田防砂工艺进行研究,发现地层物性、含水和压力是影响地层出砂的主要原因,针对这种情况,采用地层固砂、井筒挡砂清砂、携砂举升等工艺,能够有效防砂、治砂。 相似文献
167.
Mahdi Ghasemi-Varnamkhasti Seyed Saeid MohtasebiMaria Luz Rodriguez-Mendez Jesus LozanoSeyed Hadi Razavi Hojat AhmadiConstantin Apetrei 《Expert systems with applications》2012,39(4):4315-4327
Sensory evaluation is the application of knowledge and skills derived from several different scientific and technical disciplines, physiology, chemistry, mathematics and statistics, human behavior, and knowledge about product preparation practices. This research was aimed to evaluate aftertaste sensory attributes of commercial non-alcoholic beer brands (P1, P2, P3, P4, P5, P6, P7) by several chemometric tools. These attributes were bitter, sour, sweet, fruity, liquorice, artificial, body, intensity and duration. The results showed that the data are in a good consistency. Therefore, the brands were statistically classified in several categories. Linear techniques as Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) were performed over the data that revealed all types of beer are well separated except a partial overlapping between zones corresponding to P4, P6 and P7. In this research, for the confirmation of the groups observed in PCA and in order to calculate the errors in calibration and in validation, PLS-DA technique was used. Based on the quantitative data of PLS-DA, the classification accuracy values were ranked within 49-86%. Moreover, it was found that the classification accuracy of LDA was much better than PCA. It shows that this trained sensory panel can discriminate among the samples except an overlapping between two types of beer. Also, two types of artificial networks were used: Probabilistic Neural Networks (PNN) with Radial Basis Functions (RBF) and FeedForward Networks with Back Propagation (BP) learning method. The highest classification success rate (correct predicted number over total number of measurements) of about 97% was obtained for RBF followed by 94% for BP. The results obtained in this study could be used as a reference for electronic nose and electronic tongue in beer quality control. 相似文献
168.
S.I. LaoK.L. Choy G.T.S. HoY.C. Tsim T.C. PoonC.K. Cheng 《Expert systems with applications》2012,39(3):2532-2548
Food safety plan is being promoted in the food industry by the Hong Kong Government as a preliminary quality control tool. However, it appears to be a challenging task for Distribution Centers (DC) that handles food inventory since most of them are lack of knowledge and know how technology to manage information in a real time base. This paper proposes a Radio Frequency Identification based Food Operations Assignment System (RFID-FOAS) to help DC facilitates the food safety control activities in receiving areas by generating a proper safety plan. The system has adopted the Radio Frequency Identification (RFID) technology and the Case-Based Reasoning (CBR) technique to facilitate the inventory data-capturing process and assist in formulating decisions, respectively. The developed system aims to help reduce the difficulties in safety plan development using a knowledge-based expert system. The significance and contribution of RFID-FOAS in the context of managing the inventory quality in DC for safety plan development is demonstrated through the adoption of the system in a Hong Kong-based logistics company. The generated results show that the decision-making process of the safety plan development is facilitated. Moreover, the real-time data capturing nature of RFID technology has further improved the efficiency and timeframe requested for the actions. With the support of RFID-FOAS, the data capture system and the decision-making time is minimized. As a result, inventory quality and customer satisfaction level are significantly improved. 相似文献
169.
170.