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1.
An increasing number of social media and networking platforms have been widely used. People usually post the online comments to share their own opinions on the networking platforms with social media. Business companies are increasingly seeking effective ways to mine what people think and feel regarding their products and services. How to correctly understand the online customers’ reviews becomes an important issue. This study aims to propose a method with the aspect-oriented Petri nets (AOPN) to improve the examination correctness without changing any process and program. We collect those comments from the online reviews with Scrapy tools, perform sentiment analysis using SnowNLP, and examine the analysis results to improve the correctness. In this paper, we apply our method for a case of the online movie comments. The experimental results have shown that AOPN is helpful for the sentiment analysis and verifying its correctness.  相似文献   
2.
With the development of the economic and low-carbon society, high-performance building (HPB) design plays an increasingly important role in the architectural area. The performance of buildings usually includes the building energy consumption, building interior natural daylighting, building surface solar radiation, and so on. Building performance simulation (BPS) and multiple objective optimizations (MOO) are becoming the main methods for obtaining a high performance building in the design process. Correspondingly, the BPS and MOO are based on the parametric tools, like Grasshopper and Dynamo. However, these tools are lacking the data analysis module for designers to select the high-performance building more conveniently. This paper proposes a toolkit “GPPre” developed based on the Grasshopper platform and Python language. At the end of this paper, a case study was conducted to verify the function of GPPre, which shows that the combination of the sensitivity analysis (SA) and MOO module in the GPPre could aid architects to design the buildings with better performance.  相似文献   
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The primary objective of this study is to develop teaching materials for chemical engineering students (or students pursuing other related B.Sc./M.Sc. degrees) that encourage self-learning to facilitate understanding and the development of problem-solving skills. Tools are oriented to support the teaching of “Introduction to Chemical Engineering” courses to 1st year B.Sc. students in Chemical Engineering, 2nd year B.Sc. students in Chemistry, and 3rd year B.Sc. students in Biochemistry at the Universidad Complutense de Madrid (UCM). Problem generators of standard exercises, as an additional complement to the exercises that are used in the lectures, seminars, and assignments to facilitate the learning of the students, have been developed. These generators provide exercises to students with “unlimited” initial values (with certain restrictions). The software that was used to develop these materials was Jupyter Notebook, which runs under the Python 3.6 language. The problem generators can be classified into fixed problem generators, case-based generators, and random problem generators. Additionally, lecturing tools have been developed to support teaching using live/interactive examples. These examples can learning understanding of various topics of the courses.  相似文献   
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油田内部生产资料类型包括钻井、录井、测井、试油等多种类型。针对资料整理过程中存在的问题如:从原始资料库中下载的资料格式多样;不同石油软件所需加载的数据格式不同;已有资料预处理软件功能均较单一等,从编程语言优选、软件兼容性、软件功能集成化三个方面出发,选取Python语言进行软件设计,利用Python扩展性强的特点,设计出红番茄资料预处理软件,并在新疆油田进行试点,生产资料整理时间缩短至原耗时间的约33%。Python语言在油田生产中的应用可为具有相同问题的其他油田提供参考。  相似文献   
6.
为验证随机森林算法在预测改性水润滑轴承摩擦学性能上的可行性,利用Python编写算法,并通过已知实验数据进行仿真建模。通过已知数据对算法的准确性进行验证,其接受者操作特征(ROC)曲线的均值为0.85,证明模型的准确性较高。在不同温度及载荷工况条件下通过实验对预测模型进行验证,实验结果与预测结果间的误差均在5%左右,表明构建的随机森林模型可以用于改性水润滑轴承的摩擦学性能预测。研究结果表明:温度对于该改性水润滑轴承的平均摩擦因数有较大的影响,而负载对平均摩擦因数的影响较小,但是对于轴承的运转稳定性影响较大。  相似文献   
7.
Robotics will be a dominant area in society throughout future generations. Its presence is currently increasing in most daily life settings, with devices and mechanisms that facilitate the accomplishment of diverse tasks, as well as in work scenarios, where machines perform more and more jobs. This increase in the presence of autonomous robotic systems in society is due to their great efficiency and security compared to human capacity, which is thanks mainly to the enormous precision of their sensor and actuator systems. Among these, vision sensors are of the utmost importance. Humans and many animals naturally enjoy powerful perception systems, but, in robotics, this constitutes a constant line of research. In addition to having a high capacity for reasoning and decision-making, these robots incorporate important advances in their perceptual systems, allowing them to interact effectively in the working environments of this new industrial revolution. Drawing on the most basic interaction between humans, looking at the face, an innovative system is presented in this paper, which was developed for an autonomous and DIY robot. This system is composed of three modules. First, the face detection component, which detects human faces in the current image. Second, the scene representation algorithm, which offers a wider field of view than that of the single camera used, mounted on a servo-pan unit. Third, the active memory component, which was designed and implemented according to two competing dynamics: life and salience. The algorithm intelligently moves the servo-pan unit with the aim of finding new faces, follow existing ones and forgetting those that no longer appear on the scene. The system was developed and validated using a low-cost platform based on a Raspberry Pi3 board.  相似文献   
8.
传统数值方法对水力劈裂的模拟一般采用预设裂缝扩展路径,且将水流作用等效为压力荷载,难以反映裂缝渗流-开裂耦合效应. 采用自编程Python脚本程序批量插入孔隙压力黏结单元,考虑裂缝渗流-开裂耦合作用模拟准脆性材料水力劈裂随机扩展全过程. 在对经典理论模型及试验结果模拟验证的基础上,开展含多裂缝均质模型的水力劈裂全过程分析,并进一步建立混凝土细观尺度水力劈裂模型,分析骨料、界面过渡区和基体渗透性对混凝土劈裂全过程的影响. 结果表明,本研究模型可以有效模拟准脆性材料水力劈裂失效过程,准脆性材料多缝开裂过程伴随微裂缝的分叉扩展而非光滑的裂缝扩展路径,骨料及界面过渡区影响劈裂扩展路径造成裂缝分叉出现,混凝土基体的渗透性对其抵抗水力劈裂不利并影响失效软化过程.  相似文献   
9.
鉴于中长期水文预报能有效为宏观防洪形势分析和水资源管理提供科学依据,提出了Java环境下基于SpringBoot框架开发的中长期水文预报系统。该系统集成了包含随机森林、支持向量机、小波分析、贝叶斯模型平均等多种模型方法的Python模型库以提高开发效率;采用了基于RabbitMQ技术的异种语言调用与基于RESTful技术的轻量级接口设计以降低系统响应时间。并搭建了全国主要江河流域共10个断面的中长期水文预报系统作为示例进行分析,实现了中长期水文预报业务化运行,可为同类系统开发提供参考示范。  相似文献   
10.
In the generation of electricity and cogeneration, Kalina cycle is considered as one of the competitors to organic Rankine cycle. With the simplicity and identical components of the binary mixture, Kalina system makes it more prominent to get developed and implemented as well with its environmental friendly associate. This work proposes a new improved Kalina cycle system to convert the natural source from sun to useful work. The proposed system utilizes heat source suitable to medium temperature heat applications. The proposed cycle have 2 units of solar collector, favoring an additional heat recovery and higher performance. Solar hot source temperature and pressure are 190°C and 45 bar with additional flow to the turbine of 1.15 kg/s. Energy and second law analysis have considered in evaluating the performance of the proposed plant. The energy analysis shows minimum value of net power, energy efficiency and plant efficiency as 241 kW, 15.5% and 5.7. The exergy analysis defines that, to the proposed cycle, the exergy efficiency initializes at 77% with more exergy destruction at turbine with 31%. With the parametric analysis, the system is amended to have the maximum values of energy and exergy performances as 18.5%, 7.1% and 85%. The parametric study identifies the optimum value of the inlet temperature and pressure of the pump and turbine.  相似文献   
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