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91.
贾磊 《石油化工安全环保技术》2020,(1):11-12,23,I0001
通过对神华宁煤400万t/a煤化工副产品深加工综合利用项目60万t/a聚丙烯装置施工作业现场的标准化研究,从技术团队的选择、计划进度控制、现场施工管理、文档资料规范等几个方面,探讨施工作业现场标准化作业的方法,为提高施工作业现场管理提供一些有益的建议。 相似文献
92.
The integration of computer theory and practice in higher vocational colleges is the necessary condition to realize the train-
ing of professional talents and improve the comprehensive quality of skilled talents. It is also the problem that needs to be solved
first in the teaching of computer major in higher vocational colleges. This paper firstly introduces the definition and connotation of
the integration of computer theory and practice, discusses on its construction objectives and basic concepts, then analyzes the con-
struction value of the integration of computer theory and practice, including the contents of employment, professional teaching, cur-
riculum supporting and qualification examination, finally discusses on the construction scheme of the training room of the integra-
tion of computer theory and practice, and gives the objective evaluation of the construction results, hoping to effectively improve the
level of the integration of computer theory and practice, and achieve the sustainable development of teaching. 相似文献
93.
针对传统的工程地质环境系统存在的收集图像与原始图像同向性较低的问题,以下开展了基于GIS技术的工程地质环境系统的构建研究。采用设计对比实验的方式验证该系统在实际应用过程中,可提升收集图像与原始图像的同向程度。 相似文献
94.
Arianna Borrelli 《Centaurus; international magazine of the history of science and medicine》2020,62(3):406-424
In this paper, I suggest that research results from the history and philosophy of modern science provide a valuable methodological contribution for investigating early modern experimental philosophy and employ them to reassess the contribution of Giovan Battista Della Porta to its development. In modern science, the production of experimental knowledge is dependent on a complex array of communication strategies involving verbal terminology, diagrams, standardized instruments, and measurement units. Historians and philosophers have investigated the constitutive connection between such strategies and the phenomena scientists study in laboratories, showing how the two often co-evolved during the 19th and 20th centuries. Della Porta took an important first step towards the development of such methods by transforming the traditional recipe format into a strategy for mutually connecting, conceptualizing, and sharing observations made in experiments involving similar, but not identical, instruments and procedures. I use as a case study the changing manner in which he used recipes for presenting and connecting a number of pneumatic experiences from the first edition of Natural Magic (1558) until his meteorology treatise On Transmutations of Air (1610). In modern terms, those experiences can be interpreted as demonstrating the air's expansion and contraction with heat or pressure. However, today's notions of air pressure, density, and volume did not exist around 1600 and the verbal, visual, and quantitative means of expressing them had yet to be created. Della Porta did not create the modern notions, but he contributed to their emergence in a substantial way with his discussions of those pneumatic experiences. Della Porta's innovation may be described as the creation of a new epistemic genre, but it was not of a purely literary character, since the recipes also shaped the instruments and procedures they described, transforming them into new means of knowledge production in experimental philosophy. 相似文献
95.
Despite the increasing dissemination of the Building Information Modeling (BIM) approach, many firms are still far from BIM and are only starting to adopt information technologies. We conducted an ethnographic action research with an industrial partner that implements information technologies on its construction sites, with a strong preference for home-made applications. Results show that the development of such applications faces difficulties and that multiple iterations and versions are necessary before achieving the expected goals because the required competencies are lacking among internal development teams. Moreover, initial needs evolve considerably throughout the application’s development and evaluation process. However, notwithstanding the difficulties encountered during the different application development phases, the industrial partner believes the decision to be worthwhile because of the desire to have internal control over the project data and the need to consider certain specificities related to business processes. 相似文献
96.
In automotive paint shops, changes of colors between consecutive production orders cause costs for cleaning the painting robots. It is a significant task to re-sequence orders and group orders with identical color as a color batch to minimize the color changeover costs. In this paper, a Color-batching Resequencing Problem (CRP) with mix bank buffer systems is considered. We propose a Color-Histogram (CH) model to describe the CRP as a Markov decision process and a Deep Q-Network (DQN) algorithm to solve the CRP integrated with the virtual car resequencing technique. The CH model significantly reduces the number of possible actions of the DQN agent, so that the DQN algorithm can be applied to the CRP at a practical scale. A DQN agent is trained in a deep reinforcement learning environment to minimize the costs of color changeovers for the CRP. Two experiments with different assumptions on the order attribute distributions and cost metrics were conducted and evaluated. Experimental results show that the proposed approach outperformed conventional algorithms under both conditions. The proposed agent can run in real time on a regular personal computer with a GPU. Hence, the proposed approach can be readily applied in the production control of automotive paint shops to resolve order-resequencing problems. 相似文献
97.
随着经济的不断发展,国民也越来越注重食品的品质和安全。目前中小食品企业在国内得到越来越多的关注和重视。榨汁机被广泛应用在食品行业,发挥着巨大的作用。汁液获取的三种方法包括机械榨取、理化获取、酶法提取。理化和酶法在使用过程中因会产生物理化学反应,导致其他副作用从而在使用上有极大局限性,机械榨汁由于其无副作用而被企业广泛应用在蔬菜、水果上。基于此,研究了螺旋式连续榨汁机,其核心思想是以压缩体积为基础的一种机械榨取机。首先介绍了榨汁机的设计思路;其次介绍了工作原理;最后展示了榨汁机的机械组成。与传统的榨汁机相比,该方法设计的榨汁机是通过变螺距变径螺杆,从而充分地挤出新鲜果汁,具有十分重要的实际研究意义。 相似文献
98.
随着信息技术的不断发展,互联网、手机、数字电视等新媒体出现在我们的视野中,这不仅丰富了人们的日常生活,同时也给文化传播创造了便利。通过新媒体的融合应用,文化传播在内容和形式上有了新的突破,文化传播范围也得到了进一步扩大,面向世界范围进行传播和交流,文化传播内容更加丰富多彩,不仅满足受众精神需求,而且为促进文化产业发展奠定基础。重点就新媒体文化传播与实践进行研究分析,以供参考和借鉴。 相似文献
99.
Victoria Gallon Pierre Le Cann Mariangel Sanchez Charline Dematteo Barbara Le Bot 《Indoor air》2020,30(4):691-710
Building materials and human activities are important sources of contamination indoors, but little information is available regarding contamination during construction process which could persist during the whole life of buildings. In this study, six construction stages on two construction sites were investigated regarding the emissions of 43 volatile organic compounds (VOCs), 46 semi-volatile organic compounds (SVOCs), and the presence of 4 genera of mold. Results show that the future indoor air quality does not only depend on the emissions of each building product but that it is also closely related to the whole implementation process. Mold spore measurements can reach 1400 CFU/m3, which is particularly high compared with the concentrations usually measured in indoor environments. Relatively low concentrations of VOCs were observed, in relation to the use of low emissive materials. Among SVOCs analyzed, some phthalates, permethrin, and hydrocarbons were found in significant concentrations upon the delivery of building as well as triclosan, suspected to be endocrine disruptor, and yet prohibited in the treatment of materials and construction since 2014. As some regulations exist for VOC emissions, it is necessary to implement them for SVOCs due to their toxicity. 相似文献
100.
在经济不断发展的背景下,石油已经成为不可或缺的能源,其从开采至加工整个过程均需使用储油罐,所以储油罐的防腐质量十分重要,需要使用相应的涂料进行防腐。本文对石油储罐防腐涂料施工策略进行分析,以供参考。 相似文献