Investigation and Mitigation of Transformer Inrush Current during Black Start of an Independent Power Producer Plant

The energizing of large power transformers has long been considered a critical event in the operation of an electric power system. When a transformer is energized by the utility, a typical inrush current could be as high as ten times its rated current. This could cause many problems from mechanical stress on transformer windings to harmonics injection, and system protection malfunction. There have been numerous researches focusing on calculation and mitigation of the transformer inrush current. With the development of smart grid, distributed generation from independent power producers (IPPs) is growing rapidly. This paper investigates the inrush current due to black start of an IPP system with several parallel transformers, through a simulation model in DIgSILENT Power Factory software. The study demonstrates that a single genset is capable of energizing a group of transformers since the overall inrush current is slightly above the inrush of the transformer directly connected to the generator. In addition, a simple method is proposed to mitigate the inrush current of the transformers using an auxiliary transformer.

Pathways to Enhance New Quality Productivity in New Liberal Arts Education Through Artificial Intelligence

This paper explores the pathways through which artificial intelligence(AI)enhances new quality productivity in new liberal arts education.By analyzing the role of AI in personalized learning,interdisciplinary integration,and the application of virtual reality/augmented reality technologies,it reveals how AI technology promotes the development of students’innovative capabilities and productivity in the context of new liberal arts education.The study shows that AI is not only a technical tool but also a driving force for transforming educational models and fostering knowledge innovation.Further exploration of the deep integration of AI and new liberal arts education is necessary to promote comprehensive social progress.

Lynas,Australia's rare earth producer has increased its sales in 2017

As sales and demand increased in the electric car industry,Lynas,a rare earth producer in Australia,announced a surge in revenue in the second half of 2017.It was reported that the company’s six month sales up to December 31,2017 was209 million Australian dollars($155.7 million),compared with a$114.6 million in

Microsoft Producer自定义演示模板的编辑

本文介绍了Microsoft Producer中演示模板的自定义方法,以及最终浏览相关界面及显示内容的编辑。

基于Producer多媒体电子课件制作

传统课件制作流程繁琐,对硬件设备与人员要求较高,不便普及与推广.基于Producer多媒体电子课件制作是一种简单、实用、便于示范推广的课件制作方法,既然可以满足教师的日常课件制作需求,又可以满足专业人员的制作高级别多媒体电子课件的要求,为多媒体课件制作开辟了一条新思路.描述了基于Producer多媒体电子课件制作的成功案例、实现方案、工作界面、制作流程、关键技术与实现.

基于Microsoft Producer和Windows Media技术制作和发布流媒体网络课件

详细介绍了使用Microsoft Producer制作和发布基于Windows Media技术的流媒体网络课件的方法和步骤, 较好地解决了流媒体网络课件应用中的关键问题。

基于Podcast Producer的讲座资源支撑平台的设计与实现——以北京大学讲座网为例

从工作流程、网络架构、功能模块和关键技术等几个方面介绍了基于Podcast Producer开发的北京大学讲座网,并探索一个可实现信息发布、讲座录制任务分配、录制进度监控和自动转码处理与讲座视频发布等功能的高度自动化的通用讲座资源支撑平台。

用Microsoft Producer制作网络课程

Microsoft Producer for Power Point 2003是为Power Point 2003免费附加的组件,它是到目前为止最经济、最简单的、最易学的精品课程、网络课程制作软件。本文较为详细地介绍了用向导添加素材、选择模版、音视频与幻灯片同步、发布的过程。

基于Microsoft Producer的网络远程教学平台设计

通过对Microsoft Producer软件在多媒体同步技术上的应用,分析了现在网络远程教学中存在的问题,提出了在网络远程教育领域教师视频教学信息与电子教案等多媒体信息同步播放的解决方案,并设计出了基于Microsoft Producer技术的网络远程教学平台模型。

用Producer打造在线课堂

传统课堂教学受到时空的限制，学生难于实现真正的自主学习。通过producer打造在线课堂，让课堂教学具有重复性、选择性、自主性，教学方法和教学内容与受教育者的个体差异相适应，真正实现“因材施教”，体现了自主学习的特点。

“liberal arts”的源与流——古今之变中的审视

“古今之变”是审视liberal arts流变的中心线索。古典liberal arts是具有内在统一性并指向完满品格的整全性知识体系。欧洲三次文艺复兴对liberal arts的再造展现了其历史流变中的不变逻辑,即为特定时代的受教育者提供共同价值。德国古典大学赋予了liberal arts在古典意义上的完美形态,而新人文主义的自我塑造观念孕育了博雅教育的现代转向。科学革命终结了古典学术的内在统一性与道德理想,瓦解了古典liberal arts。美国现代大学则借助古典资源,经由三次改革浪潮重建了liberal arts。然而,古典教育凝聚文明精华的共同价值、塑造意义与学术整合力量,同现代科学的智识自由、价值分殊与学科分化特性相冲突,这是古今之变为现代大学再造liberal arts所深植的困境,liberal arts只能在钟摆的两端之间不断权衡。

Application of digital pattern-less molding technology to produce art casting

Compared with the conventional casting process, digital pattern-less casting technology has many advantages such as good machining accuracy, a short processing cycle, and low production cost. It is a new rapid manufacturing technology for castings, integrated with CAD/CAM, casting, CNC machining and many other advanced technologies. With this digital casting technology, no pattern is needed for making molds; it is precise, f lexible, and green. Usually, art castings have complex structures and are made in small batches or even made in a single-piece, especially for large-sized art castings. So it has the shortcomings of high cost, low eff iciency and long time for making a pattern to produce art castings with the conventional casting processes. However, the digital pattern-less casting technology can be applied to fabricate art castings, since it can greatly shorten the manufacturing cycle and lower the production cost, thus having a very good prospect. In this study, based on the digital pattern-less casting technology, a plaque casting with artistic Chinese characters(a Chinese poem) was designed and manufactured, and the production process was demonstrated in detail.

Evolutionary game analysis between the government and the waste producer in the venous industry

The relationship between the government and the waste producer is always a representative and realistic issue,especially concerning the venous industry.This article is based on the true relationship between the government and the waste producer,uses the methods from the evolutionary game theory,and analyzes the relationship between the government and the waste producer in detail.

An Empirical Study on Chinese City Network Pattern Based on Producer Services

Globalization and informatization have accelerated city networking process over the world, which makes research on city network a hot topic in the fields of urban geography and economic geography. With Chinese economic structure adjustment and city economic growth, producer services have begun to play an increasingly important role in city-region networking. This paper employs the methodology of world city network to analyze and explain the spatial development characteristics of China's urban network system based on the data of nationwide producer services enterprise network. The research result indicated that the distribution of producer services network has a positive effect on the development of Chinese city networks. City network connectivity is closely related to the significance of city in producer services development, and the former will gradually decline with the drop of the latter. Accordingly, the 64 cities can be divided into the national central cities, regional central cities, sub-regional central cities and local central cities in accordance with their position and role in the nationwide producer services network. It is concluded that high-grade cities with quality producer services dominate the pattern of Chinese city networks and there emerges three spatial agglomerations of producer services enterprises in Changjiang (Yangtze) River Delta, Zhujiang (Pearl) River Delta and Beijing-Tianjin-Tangshan Economical Region. Moreover, the distribution of different producer services industry varies from city to city, which also affects the characteristics of network development.

Relationship Between Producer Services Developing Level and Urban Hierarchy——A Case Study of Zhujiang River Delta

As the Central Place Theory indicates, the centricity of a central city can influence the extension of its ser- vice. Since the service industry in the theory is mostly consumer services, it is worth studying the relationship between the producer services and the centricity of the city in the service society with producer services becoming a more im- portant part of the service industry. The paper takes the case of the Zhujiang (Pearl) River Delta (PRD), a developed region in China, to study the relationship between the developing level of producer services and the urban hierarchy. Based on the analysis about the spatial difference of the producer services in the nine cities of the PRD, and the divi- sion of the nine cities according to some economic indices, it is shown that there is a correlation between the develop- ing level of producer services and the urban hierarchy. Furthermore, two deductions about the future status of the pro- ducer services in the city and the location of the producer services in a large region can be made from this correlation between the developing level of producer services and the urban hierarchy.

SWOT Analysis of Agricultural Producers in the Supply Chain of Chinese Agro-products

On the basis of defining the producers in the supply chain of agricultural products,the SWOT analysis is adopted to analyze the advantages,disadvantages,opportunities and threats of producers in the supply chain of Chinese agricultural products.The paper analyzes the advantages of producers in the supply chain of agricultural products from three aspects including land resources,technology level of producers and input costs.The disadvantages of producers in the supply chain of agricultural products are analyzed from three aspects including scale level,mechanization and technology level and profit level.The opportunities of producers in the supply chain of agricultural products are analyzed from the aspects of laws,policies,capitals and technologies.The threats confronted by the producers in the supply chain of agricultural products are analyzed from foreign producers,negotiation control of supply chain of agricultural chain,environment protection and quality safety standard.On the basis of the analysis,the relevant suggestions on facilitating the interests of producers in the supply chain of Chinese agricultural products are put forward,including fully displaying the advantages of land resources;improving the knowledge and technology level of supply chain of agricultural production;establishing the alliances of producers of agricultural products to expand production scale;improving the quality of agricultural products to satisfy the relevant safety quality standard and environmental protection standard.

Producer/Consumer通信模式在ControlNet上的实现

本文主要介绍了Producer/Consumer通信模式的传送原理,以及它是如何通过CTDMA算法在ControlNet上实现的,并说明了ControlNet的组态及网络中的Keeper所发挥的作用。另外,根据使用ControlNet的经验,介绍了在使用ControlNet时应该注意的一些问题。

医护-社会组织一体化模式对HIV/AIDS患者ART及自我管理能力的影响

探究接受高效抗反转录病毒治疗确诊HIV/AIDS患者接受医护-社会组织一体化模式干预价值。方法 从2022年1月至2022年12月南昌市某定点医院接受抗病毒治疗及随访管理的新确诊HIV/AIDS患者100例,50例接受传统医护合作模式对照组、50例接受医护-社会组织一体化模式观察组,两组各项临床指标差异进行分析对比(从HIV抗体初筛阳性到启动ART治疗时间、抗病毒治疗一年后HIV病毒载量的指标及病毒抑制率、抗病毒治疗一年后自我管理能力)。结果 干预后与对照组比较,观察组HIV抗体初筛阳性到启动ART治疗时间显著偏低,HIV病毒载量指标水平显著偏低,病毒抑制率显著偏高,一年后自我管理能力评分显著偏高,用药依从性显著偏高(P<0.05)。结论 接受抗病毒治疗及随访管理的确诊HIV/AIDS患者接受医护-社会组织一体化模式干预后,可显著提高患者自我管理能力。此外,还能保障高病毒抑制率,缩短患者治疗时间,提升患者用药依从性。

Conversion of producer gas using NiO/SBA-15 obtained with different synthesis methods

In this study,NiO/SBA-15 was prepared by both direct and post synthesis methods.TEM images revealed that NiO particles aggregated in NiO/SBA-15 obtained with post synthesis method,regardless of NiO loading.However,NiO particles were monodispersed in NiO/SBA-15 with a NiO loading of less than 15 wt%by using the direct synthesis method.In this case,NiO particles aggregated when NiO loading was over 20 wt%.TPR analysis verified that with direct synthesis method the location boundary of NiO particles on outer and pore surface could be observed clearly,whereas that could not observed in the case of post synthesis method.This indicates that the type of synthesis method displays significant effect on the location of NiO particles dispersed into the SBA-15.Producer gas conversion was carried out using NiO/SBA-15 as catalysts,which were synthesized with different synthesis methods.The gas conversion including methanation occurred at low temperature(i.e.,300-400℃)and the reverse water gas shift(RWGS)reaction at hightemperature(i.e.,400-900℃).High temperatures facilitated CO conversion to CO with CO selectivity close to 100%,regardless of the synthesis method of the used catalyst.At low temperatures the dispersion type of NiO particles affectedthe CO,conversion reaction,i.e.,monodispersed Ni0 particles gave a CO selectivity of close to 100%,similar to thatobtained at high temperature.The aggregated NiO particles resuled in a CO selectivity of less than 100%owing to CH,formation,regardless of synthesis method of catalyst.Therefore,NiO/SBA-15 obtained with direct synthesis methodfavored RWGS reaction because of high CO selectivity.NiOSBA-15 obtained with post synthesis method is suited formethanation because of high CH selectivity,and the conversion of CO,to CHa through methanation increased withincreasing NiO loading.