Operation And Maintenance
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2022 ◽  
Author(s):  
Thomson Mtonga ◽  
Keren K. Kaberere ◽  
George Kimani Irungu

<div>The installation of shunt capacitors in radial distribution systems leads to reduced branch power flows, branch currents, branch power losses and voltage drops. Consequently, this results in improved voltage profiles and voltage stability margins. However, for efficient attainment of the stated benefits, the shunt capacitors ought to be installed in an optimal manner, that is, optimally sized shunt capacitors need to be installed at the optimum buses of an electrical system. This article proposes a novel approach for optimizing the placement and sizing of shunt capacitors in radial distribution systems with a focus on minimizing the cost of active power losses and shunt capacitors’ purchase, installation, operation and maintenance. To reduce the search space, hence the computation time, the prroposed approach starts the search process by arranging the buses of the radial distribution system under consideration in pairs. Thereafter, these pairs influence each other to determine the optimum total number of buses to be compensated. The proposed approach was tested on the 34- and 85-bus radial distribution systems and when the simulation results were compared with those obtained by other approaches, it was established that the developed approach was a better option because it gave the least cost.</div>


2022 ◽  
Author(s):  
Thomson Mtonga ◽  
Keren K. Kaberere ◽  
George Kimani Irungu

<div>The installation of shunt capacitors in radial distribution systems leads to reduced branch power flows, branch currents, branch power losses and voltage drops. Consequently, this results in improved voltage profiles and voltage stability margins. However, for efficient attainment of the stated benefits, the shunt capacitors ought to be installed in an optimal manner, that is, optimally sized shunt capacitors need to be installed at the optimum buses of an electrical system. This article proposes a novel approach for optimizing the placement and sizing of shunt capacitors in radial distribution systems with a focus on minimizing the cost of active power losses and shunt capacitors’ purchase, installation, operation and maintenance. To reduce the search space, hence the computation time, the prroposed approach starts the search process by arranging the buses of the radial distribution system under consideration in pairs. Thereafter, these pairs influence each other to determine the optimum total number of buses to be compensated. The proposed approach was tested on the 34- and 85-bus radial distribution systems and when the simulation results were compared with those obtained by other approaches, it was established that the developed approach was a better option because it gave the least cost.</div>


2022 ◽  
Vol 2022 ◽  
pp. 1-15
Author(s):  
Huachao Yang ◽  
Hefang Bian ◽  
Bin Li ◽  
Weihua Bi ◽  
Xingtao Zhao

Newly developed oblique photogrammetry (OP) techniques based on unmanned aerial vehicles (UAVs) equipped with multicamera imaging systems are widely used in many fields. Smartphones cost less than the cameras commonly used in the existing UAV OP system, providing high-resolution images from a built-in imaging sensor. In this paper, we design and implement a novel low-cost and ultralight UAV OP system based on smartphones. Firstly, five digital cameras and their accessories detached from the smartphones are then fitted into a very small device to synchronously shoot images at five different perspective angles. An independent automatic capture control system is also developed to realize this function. The proposed smartphone-based multicamera imaging system is then mounted on a modified version of an existing lightweight UAV platform to form a UAV OP system. Three typical application examples are then considered to evaluate the performance of this system through practical experiments. Our results indicate that both horizontal and vertical location accuracy of the generated 3D models in all three test applications achieve centimeter-level accuracy with respect to different ground sampling distances (GSDs) of 1.2 cm, 2.3 cm, and 3.1 cm. The accuracy of the two types of vector maps derived from the corresponding 3D models also meet the requirements set by the surveying and mapping standards. The textural quality reflected by the 3D models and digital ortho maps (DOMs) are also distinguishable and clearly represent the actual color of different ground objects. Our experimental results confirm the quality and accuracy of our system. Although flight efficiency and the accuracy of our designed UAV OP system are lower than that of the commercial versions, it provides several unique features including very low-cost, ultralightweight, and significantly easier operation and maintenance.


2022 ◽  
Vol 6 (1) ◽  
pp. 28-36
Author(s):  
Liang Pan

Under the context that “peak carbon emissions” and “carbon neutrality” are included in the overall plan for the construction of ecological civilization in China, this paper discusses the value of modern timber architecture as a form of low-carbon and environmental protection movement in the whole life cycle of the construction field. It mainly analyzes the reasons for the limited resources, misunderstandings of inherent concepts, the high cost of comprehensive construction, and the shortage of professionals. Based on that, several countermeasures have been proposed, such as perfecting relevant norms and policies, strengthening technology research and development as well as demonstration guidance, moderately developing forest resources, applying digital construction operation and maintenance technology, as well as cultivating compound professionals, all of which provide a reference for the development of ecological benefits in China’s construction industry.


2022 ◽  
Vol 12 (2) ◽  
pp. 711
Author(s):  
Iván F. Mondragón Bernal ◽  
Natalia E. Lozano-Ramírez ◽  
Julian M. Puerto Cortés ◽  
Sergio Valdivia ◽  
Rodrigo Muñoz ◽  
...  

Safety-focused training is essential for the operation and maintenance concentrated on the reliability of critical infrastructures, such as power grids. This paper introduces and evaluates a system for power substation operational training by exploring and interacting with realistic models in virtual worlds using serious games. The virtual reality (VR) simulator used building information modelling (BIM) from a 115 kV substation to develop a scenario with high technical detail suitable for professional training. This system created interactive models that could be explored using a first-person-perspective serious game in a cave automatic virtual environment (CAVE). Different operational missions could be carried out in the serious game, allowing several skills to be coached. The suitability for vocational training carried out by utility companies was evaluated in terms of usability and engagement. The evaluation used a System Usability Scale (SUS) and a Game Engagement Questionnaire (GEQ) filled by 16 power substation operators demonstrating marginally acceptable usability, with improvement opportunities and high acceptance (by utility technicians) of this system for operation training focused on safety in such hazardous tasks.


2022 ◽  
Author(s):  
Albachew Shumye ◽  
Tesfa Worku Meshesha

Abstract Background: Irrigation scheme performance assessment is vital to evaluate the impacts of irrigation practices, to identify performance gaps and to improve system performances. However, irrigation performance assessment has not been carried out for Yelen irrigation scheme since its operation. Therefore, this study has been done with the purpose of identifying and understanding the current level of irrigation performance of Yelen irrigation scheme. The indicators of adequacy, efficiency, dependability, deficiency and equity were used to determine hydraulic performance. Primary data were collected through flow measurement using current meter and Parshall flume, transect walk, household surveys and group discussions, whereas Secondary data were collected from different sources. CROPWAT 8.0 model, SPSS, Microsoft excels and GIS software was used to analyze the data. Water delivery indicators were evaluated from the amounts of water which was actually applied and which should have been applied.Results: According to the results of the study, the value of adequacy, dependability, efficiency, deficiency and equity were found to be 0.84, 0.26, 0.93, 0.17and 0.34 respectively. Generally, the performance of the irrigation system is poor. It mainly resulted due to water scarcity, illegal water abstraction, sedimentation of canals and inadequate operation and maintenance provisions.Concussions: Therefore, adequate maintenance and suitable management approaches are required to improve the irrigation system performance. Under the water scarce situations, improving the performance of water delivery systems can offer an opportunity to realize field level water savings.


Energies ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 504
Author(s):  
Harriet Fox ◽  
Ajit C. Pillai ◽  
Daniel Friedrich ◽  
Maurizio Collu ◽  
Tariq Dawood ◽  
...  

Offshore wind farms are a rapidly developing source of clean, low-carbon energy and as they continue to grow in scale and capacity, so does the requirement for their efficient and optimised operation and maintenance. Historically, approaches to maintenance have been purely reactive. However, there is a movement in offshore wind, and wider industry in general, towards more proactive, condition-based maintenance approaches which rely on operational data-driven decision making. This paper reviews the current efforts in proactive maintenance strategies, both predictive and prescriptive, of which the latter is an evolution of the former. Both use operational data to determine whether a turbine component will fail in order to provide sufficient warning to carry out necessary maintenance. Prescriptive strategies also provide optimised maintenance actions, incorporating predictions into a wider maintenance plan to address predicted failure modes. Beginning with a summary of common techniques used across both strategies, this review moves on to discuss their respective applications in offshore wind operation and maintenance. This review concludes with suggested areas for future work, underlining the need for models which can be simply incorporated by site operators and integrate live data whilst handling uncertainties. A need for further focus on medium-term planning strategies is also highlighted along with consideration of the question of how to quantify the impact of a proactive maintenance strategy.


Pharmaceutics ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 149
Author(s):  
Michael Choi ◽  
Stuart C. Porter ◽  
Axel Meisen

Oral solid dosage forms that contain APIs in the amorphous state have become commonplace because of many drug substances exhibiting poor water solubility, which negatively impacts their absorption in the human GI tract. While micronization, solvent spray-drying, and hot-melt extrusion can address solubility issues, spray coating of the APIs onto beads and tablets offers another option for producing amorphous drug products. High-level comparisons between bead and tablet coating technologies have the potential for simpler equipment and operation that can reduce the cost of development and manufacturing. However, spray coating directly onto tablets is not without challenges, especially with respect to meeting uniformity acceptance value (AV) criteria, comprising accuracy (mean) and precision (variance) objectives. The feasibility of meeting AV criteria is examined, based on mathematical models for accuracy and precision. The results indicate that the main difficulty in manufacturing satisfactory drug-layered tablets by spray coating is caused by the practical limitations of achieving the necessary coating precision. Despite this limitation, it is shown that AV criteria can be consistently met by appropriate materials monitoring and control as well as processing equipment setup, operation, and maintenance.


Author(s):  
Hongwen Xia

When identifying the enterprise database data information, the enterprise database operational dimension measurement platform based on the bilinear method will produce ringing or overshoot effect, the database data monitoring effect is poor as well as the accuracy of operation measurement. To solve this problem, this paper proposes a method to build an enterprise level database operation and maintenance measurement platform based on bidirectional coupling algorithm. Build enterprise database operation measurement platform. The enterprise database monitoring platform is connected with the monitoring database by remote database chain. The Oracle database job scheduling method is used to obtain the monitoring index information in the monitored database, and the database memory performance is comprehensively evaluated by MPI (Memory Perform Index). The platform uses semantic capture layer and related analysis layer to distinguish user behavior, analyze user experience satisfaction, and realize the operation measurement of enterprise level database. The experimental results show that the operational measurement platform built by this method has high throughput, low memory occupancy rate, high measurement accuracy and good user experience.


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