scholarly journals Cost of Industrial Process Shutdowns due to Voltage Sag and Short Interruption

Energies ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2874
Author(s):  
Édison Massao Motoki ◽  
José Maria de Carvalho Filho ◽  
Paulo Márcio da Silveira ◽  
Natanael Barbosa Pereira ◽  
Paulo Vitor Grillo de Souza

The objective of this work is to propose and apply a methodology to obtain the cost of industrial process shutdowns due to voltage sag and short interruption. A field survey, aided by a specific questionnaire, was carried out in several industries connected to medium voltage networks, in the states of Espírito Santo and São Paulo in Brazil. The results obtained were the costs per event and the costs per demand in a total of 33 companies in 12 different types of activities. It is noteworthy that this survey brings a relevant technical contribution to the electricity sector, helping to fill, even partially, an existing gap in both national and international literature.

Energies ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 3079 ◽  
Author(s):  
Leopoldo Angrisani ◽  
Francesco Bonavolontà ◽  
Annalisa Liccardo ◽  
Rosario Schiano Lo Moriello

In this paper, a logic selectivity system based on Long Range (LoRa) technology for the protection of medium-voltage (MV) networks is proposed. The development of relays that communicate with each other using LoRa allows for the combination of the cost-effectiveness and ease of installation of wireless networks with long-range coverage and reliability. The realized demonstrator to assess the proposed system is also presented in the paper; based on different types of faults and different locations, the times needed for clearing a fault and restoring the network were estimated from repeated experiments. The obtained results confirm that, with an optimized design of transmitted packets and of protocol characteristics, LoRa communication grants fault management that meets the criteria of logic selectivity, with fault isolation occurring within the maximum allowed time.


The article deals with the distribution of agricultural periodicals on the territory of the Russian Em-pire in the early twentieth century. Before that there were practically no publications on the pages of sci-entific magazines. Great emphasis is placed on the analysis of agricultural magazines published before 1917 in the Upper Volga region, namely in Vladimir, Kostroma, Tver and Yaroslavl provinces. Thanks to existed in pre-revolutionary Russian periodicals on agricultural subjects advanced knowledge of agron-omy, agriculture, soil science, horticulture, fruit growing, vegetable growing, winemaking, viticulture, 135 tobacco growing, livestock, poultry, bee-keeping, veterinary medicine, forestry, and hunting, land man-agement, irrigation, horse breeding were promoted. On the basis of statistical data, office documentation and other published sources, the author draws conclusions about the degree of accessibility of agricul-tural periodicals for the population, including the peasantry. Availability of agricultural periodicals largely depended on its price, so the author studied the situation with the cost of the annual subscription fee of these publications. The article investigates the issues of periodicity of agricultural magazines and newspapers, the exact number of such publications, as well as their subject matter. Existence duration of different types of periodicals is analyzed, the main publishers of magazines and newspapers, places of their publication are revealed. A prominent place is given to the publishing activities of agricultural pub-lic organizations and zemstvo self-government bodies. It is concluded that natural process of agricultural knowledge distribution among the population of Russia through publications on the pages of periodicals was disrupted by revolutionary events of 1917.


Author(s):  
Md. Sahidur Rahman ◽  
Md. Omar Faruk ◽  
Sumiya Tanjila ◽  
Nur Mohammad Sabbir ◽  
Najmul Haider ◽  
...  

Abstract Background Studying the characteristics of Aedes mosquito habitats is essential to control the mosquito population. The objective of this study was to identify the breeding sites of Aedes larvae and their distribution in Chattogram, Bangladesh. We conducted an entomological survey in 12 different sub-districts (Thana) under Chattogram City, during the late monsoon (August to November) 2019. The presence of different wet containers along with their characteristics and immature mosquitoes was recorded in field survey data form. Larvae and/or pupae were collected and brought to the laboratory for identification. Results Different indices like house index, container index, and the Breteau index were estimated. The multiple logistic regression analysis was applied to identify habitats that were more likely to be positive for Aedes larvae/pupae. A total of 704 wet containers of 37 different types from 216 properties were examined, where 52 (7.39%) were positive for Aedes larvae or pupae. Tire, plastic buckets, plastic drums, and coconut shells were the most prevalent container types. The plastic group possessed the highest container productivity (50%) whereas the vehicle and machinery group was found as most efficient (1.83) in terms of immature Aedes production. Among the total positive properties, 8% were infested with Aedes aegypti, 2% with Aedes albopictus, and 1% contained both species Ae. aegypti and A. albopictus. The overall house index was 17.35%, the container index was 7%, and the Breteau index was 24.49. Containers in multistoried houses had significantly lower positivity compared to independent houses. Binary logistic regression represented that containers having shade were 6.7 times more likely to be positive than the containers without shade (p< 0.01). Conclusions These findings might assist the authorities to identify the properties, containers, and geographical areas with different degrees of risk for mosquito control interventions to prevent dengue and other Aedes-borne disease transmissions.


Sensors ◽  
2021 ◽  
Vol 21 (16) ◽  
pp. 5300
Author(s):  
Antonia Nisioti ◽  
George Loukas ◽  
Stefan Rass ◽  
Emmanouil Panaousis

The use of anti-forensic techniques is a very common practice that stealthy adversaries may deploy to minimise their traces and make the investigation of an incident harder by evading detection and attribution. In this paper, we study the interaction between a cyber forensic Investigator and a strategic Attacker using a game-theoretic framework. This is based on a Bayesian game of incomplete information played on a multi-host cyber forensics investigation graph of actions traversed by both players. The edges of the graph represent players’ actions across different hosts in a network. In alignment with the concept of Bayesian games, we define two Attacker types to represent their ability of deploying anti-forensic techniques to conceal their activities. In this way, our model allows the Investigator to identify the optimal investigating policy taking into consideration the cost and impact of the available actions, while coping with the uncertainty of the Attacker’s type and strategic decisions. To evaluate our model, we construct a realistic case study based on threat reports and data extracted from the MITRE ATT&CK STIX repository, Common Vulnerability Scoring System (CVSS), and interviews with cyber-security practitioners. We use the case study to compare the performance of the proposed method against two other investigative methods and three different types of Attackers.


Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2146
Author(s):  
Karunesh Kant ◽  
Karthik Nithyanandam ◽  
Ranga Pitchumani

This paper analyzes a novel, cost-effective planar waveguide solar concentrator design that is inspired by cellular hexagonal structures in nature with the benefits of facile installation and low operation and maintenance cost. A coupled thermal and optical analysis of solar irradiation through an ideal hexagonal waveguide concentrator integrated with a linear receiver is presented, along with a cost analysis methodology, to establish the upper limit of performance. The techno-economic model, coupled with numerical optimization, is used to determine designs that maximized power density and minimized the cost of heat in the temperature range of 100–250 °C, which constitutes more than half of the industrial process heat demand. Depending on the incident solar irradiation and the application temperature, the cost of heat for the optimal design configuration ranged between 0.1–0.27 $/W and 0.075–0.18 $/W for waveguide made of ZK7 glass and polycarbonate, respectively. A techno-economic analysis showed the potential of the technology to achieve cost as low as 80 $/m2 and 61 $/m2 for waveguide made of ZK7 glass and polycarbonate material, respectively, which is less than half the cost of state-of-the-art parabolic trough concentrators. Overall, the hexagonal waveguide solar concentrator technology shows immense potential for decarbonizing the industrial process heat and thermal desalination sectors.


Energies ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2885
Author(s):  
Daniel Losada ◽  
Ameena Al-Sumaiti ◽  
Sergio Rivera

This article presents the development, simulation and validation of the uncertainty cost functions for a commercial building with climate-dependent controllable loads, located in Florida, USA. For its development, statistical data on the energy consumption of the building in 2016 were used, along with the deployment of kernel density estimator to characterize its probabilistic behavior. For validation of the uncertainty cost functions, the Monte-Carlo simulation method was used to make comparisons between the analytical results and the results obtained by the method. The cost functions found differential errors of less than 1%, compared to the Monte-Carlo simulation method. With this, there is an analytical approach to the uncertainty costs of the building that can be used in the development of optimal energy dispatches, as well as a complementary method for the probabilistic characterization of the stochastic behavior of agents in the electricity sector.


2021 ◽  
Vol 13 (7) ◽  
pp. 3850
Author(s):  
Ting Liu ◽  
Gabriel Lodewijks

This paper proposed a scheme design for Sydney’s frontport check-in system, which completes check-in and baggage drop-off at Sydney’s Circular Quay, and transports the baggage to Sydney Kingsford Smith Airport by waterway, and provided a strengths, weaknesses, opportunities and threats (SWOT) analysis of Sydney’s frontport check-in system. Using the process method of quality management, the frontport check-in process was divided into three sub-processes: baggage consignment, baggage packing and transportation, and airport baggage handling. The eight key elements of each sub-process such as input, output, resources, and methods, etc. were discussed, the key factors influencing the cost of baggage transportation were analyzed, and the cost control measures such as adopting economic speed, reducing fuel consumption of the main engine, improving the ship loading rate, and raising loading and unloading efficiency were proposed. At the same time, two different types of baggage transportation ships and other parameters that affect the cost such as the number of berths, ships, lifting machineries, and the yard area were analyzed and calculated through calculation cases. This scheme is a beneficial addition to the existing in-town check-in system.


2016 ◽  
Vol 15 (1) ◽  
pp. 27
Author(s):  
I Wayan Agus Teja Baskara ◽  
I G Dyana Arjana ◽  
I W Rinas

Ground wire is one of the lighning protection instrument used in medium voltage distribution network with the intention to reduce interference due to lightning strikes. On the feeder Serangan the ground wire put 4 – 5 wicket. To know effective gap of ground wire is put on the feeder Serangan then used effectiveness ground wire parameters and total of disorder by lightning strikes directly or indirectly. From the analysis is obtained the effective gap on scenario 4 by 3 – 4 wicket. Choosing scenario 4 is as effective gap because seen by economic aspect, as longest gap point put of ground wire then the cost needed to use material and the installation of ground wire will be cheaper.  DOI: 10.24843/MITE.1501.05


Author(s):  
Fidelia Johny ◽  
Noorasmah Saupi ◽  
Shiamala Devi Ramaiya

Pepper (Piper nigrum L.) is one of the most important cash crops in Sarawak. The productivity of pepper is consistently low due to the low yield of berry production. One of the major problems of pepper production is inconsistent flowering time. This is due to the morphology and inheritance of functional male, female and hermaphrodite (bisexual) flower in P. nigrum which affect the productivity of pepper. For the exploitation of pepper for its maximum production, the detailed of flower development and flower composition are important factors to be considered. A field survey was conducted to determine the status of farming practices and problems encountered by the farmers. The study was also done to determine the composition of flower which influenced the consistency of berry production in P. nigrum in Sarawak. Surveys were conducted at 18 pepper farms in Sarawak to determine the composition of flowers in different types of Sarawak pepper varieties which are Kuching, Semenggok Aman and Semenggok Emas. Nine spikes were harvested in each pepper vine. Three pepper vines were selected randomly for each variety. The spikes were then observed under 3D Keyence microscope to determine the number of flowers of each type of flower. The survey on the farming practices were also conducted. The composition of flower was found to be varied between varieties. ‘Kuching’ variety had less hermaphrodite flower when compared to ‘Semenggok Aman’ and ‘Semenggok Emas’ varieties. In addition, a proportion of 29% farmers had encountered root rot disease problem in their farm, while 21% stated that unsynchronisation of berries production in each harvesting time as a major problem.


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