scholarly journals Methodology for assessing the power of the primary source of the system of autonomous electrical supply with account of the predicted load graphics

2019 ◽  
Vol 64 (2) ◽  
pp. 205-214
Author(s):  
D. V. Karkotski ◽  
A. N. Malashin ◽  
S. A. Chumakov ◽  
Y. G. Koval
Keyword(s):  
Supply Voltage ◽  
Electric Energy ◽  
Operation Time ◽  
Primary Source ◽  
Electrical Energy ◽  
Quality Parameters ◽  
Limited Information ◽  
Autonomous Operation ◽  
Current Consumption ◽  
The Impact

When developing new or upgrading existing energy-intensive mobile objects (MO), the main way to ensure the quality parameters of the supply voltage is no worse than in the state grid, overestimation of the primary source (PS) power is 1.5–2 times relative to the maximum power of all electrical energy consumers (EEC) software.The consequence of the existing approach to determine the power of PS are: overestimation of the mass and dimensions of the autonomous power supply system (APSS) by 30–70 %, which significantly reduces speed characteristics, cross-country performance and battery autonomy of MO, as well as worsen the economics of the APSS; the workload of the PS APSS is not more than 35–55 % of the nominal capacity, which leads to a reduction in their service lives.Thus, it is impossible to take into account the peculiarities of the actual current consumption of individual EEC and the impact of their joint operation on specific PS APSS, which leads to additional financial costs and an increase in development time, as well as to the risk of failure during the testing of both the APSS and the equipment connected to it.The proposed approach for estimating the PS power of electric energy in APSS MO allows determining the full power of the EEC in terms of limited information about the EEC taking into account the nature of the load graph, as well as the magnitude and form of current consumption. As a result of analytical calculations according to the above methodology, the PS power can be reduced by 13–45 %, depending on the nature of the load, while maintaining the quality indicators of the supply voltage within acceptable limits.The considered methods for determining the power of the PS APSS will make it possible to determine the limitations for solving the problem of structural-parametric synthesis of the APSS and the algorithm for determining the power of the PS when developing a new or upgrading the existing APSS MO. This will reduce the weight and size parameters of the APSS, thereby increasing the speed characteristics, maneuverability and software permeability of MO, as well as the autonomous operation time and efficiency of the APSS operation.

The utility of biochar for increasing the fertility of new agricultural lands converted from boreal forests

2021 ◽  
Author(s):  
Joinal Abedin ◽  
Adrian Unc
Keyword(s):  
Boreal Forests ◽  
Agricultural Soils ◽  
Nutrient Retention ◽  
Quality Parameters ◽  
Limited Information ◽  
Agricultural Lands ◽  
Retention Capacity ◽  
Beneficial Effects ◽  
Diminishing Returns ◽  
The Impact

The agricultural soils of the Happy Valley-Goose Bay (HV-GB) region of Newfoundland and Labrador, Canada are Podzols that are converted from boreal forest and have limited productivity due to their sandy texture, acidity, low soil organic matter (SOM), CEC, and water and nutrient retention capacity. While numerous studies advocate biochar for mitigating soil quality problems and enhancing agronomic productivity, there is limited information on managing biochar for boosting productivity of Podzols under newly converted agricultural lands. A 5-year experiment evaluated the impact of eight biochar rates (0 to 80 Mg C ha-1) on soil properties including SOM, CEC, and availability of plant nutrients and metals in agricultural soils of HV-GB. Both immediate and long term impacts were thus assessed. Biochar generally improved soil fertility indicators. While the largest rates (40 and 80 Mg C ha-1) led to the greatest changes, significant changes were also found with rates as low as 10 Mg C ha-1. Increasing biochar rates had diminishing returns for soil’s quality parameters. The impact of biochar decreased with time after application, but the largest rate led to longer lasting effects. Although biochar was incorporated in topsoil, its effects were also measurable in the subsoil, albeit with a temporal delay, usually of one year. Thus, given the diminishing returns of increasing biochar rates, and that beneficial effects diminish over years, it is advisable that biochar be added in smaller amounts immediately after conversion, as little as 10 Mg C ha-1, with regular supplementation as needed.

scholarly journals The Effect of High-Fat Diet-Induced Obesity on the Expression of Nutrient Chemosensors in the Mouse Stomach and the Gastric Ghrelin Cell

Nutrients ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2493
Author(s):  
Maria Nunez-Salces ◽  
Hui Li ◽  
Stewart Christie ◽  
Amanda J. Page
Keyword(s):  
High Fat Diet ◽  
Primary Source ◽  
Nutrient Sensing ◽  
Mrna Levels ◽  
Limited Information ◽  
High Fat ◽  
Diet Induced Obesity ◽  
Standard Laboratory Diet ◽  
Ghrelin Secretion ◽  
The Impact

The stomach is the primary source of the orexigenic and adiposity-promoting hormone, ghrelin. There is emerging evidence on the nutrient-mediated modulation of gastric ghrelin secretion. However, limited information is available on gastric nutrient-sensing mechanisms in high-fat diet (HFD)-induced obesity. This study investigated the impact of HFD-induced obesity on the expression of nutrient chemosensors in mouse stomach, particularly ghrelin cells. Male C57BL/6 mice were fed either a standard laboratory diet (SLD) or HFD for 12 weeks. The expression of ghrelin, enzymes involved in ghrelin production (PC1/3, GOAT) and nutrient chemosensors (CD36, FFAR2&4, GPR93, CaSR, mGluR4 and T1R3) was determined by quantitative RT-PCR in the mouse corpus and antrum. Immunohistochemistry assessed the protein expression of CaSR and ghrelin in the corpus and antrum. Antral mRNA levels of CaSR and PC1/3 were increased in HFD compared to SLD mice, while mRNA levels of all other nutrient chemosensors examined remained unchanged. CaSR immunolabelling was observed in the gastric antrum only. Nearly 80% of antral ghrelin cells expressed CaSR, with a similar cell density and co-expression in SLD and HFD mice. In conclusion, HFD-induced obesity increased CaSR mRNA expression in mouse antrum. However, the high antral co-expression of CaSR and ghrelin was unaltered in HFD compared to SLD mice.

Political-economic, social and environmental aspects of sugar cane biomass use for the electrical energy generation

2020 ◽  
Vol 13 (3) ◽  
pp. 77
Author(s):  
A. Areias
Keyword(s):  
Rural Communities ◽  
Environmental Impacts ◽  
Fossil Fuels ◽  
Nutrient Recycling ◽  
Electric Energy ◽  
Electrical Energy ◽  
Reduction Of Co2 ◽  
Agricultural Areas ◽  
Political Economic ◽  
The Impact

Energy produced through biomass, when produced in an efficient and sustainable way, generates a series of environmental, economic and social benefits when compared to the use of fossil fuels. Benefits such as better land management, job creation, efficient use of agricultural areas, provision of modern energy vectors to rural communities, reduction of CO2 emissions, waste control and nutrient recycling can be highlighted. This paper discusses the contributions of energy co-generation, from biomass, to the supplementation of electric energy, reduction of environmental impacts and generation of employment. The aim was to understand the impact of public policies to increase the efficiency of the sugar-energy sector and if there was an increase in employment and manpower in the field, as well as reduction of environmental impacts by reducing the consumption of other less renewable sources of energy within the State from São Paulo. In order to carry out this study, it was necessary to analyze the social, economic and agronomic indicators and the energy plans that aim at the development of the sector, such as the National Energy Plan and the Paulista Energy Plan.

scholarly journals Long-Term Performance Analysis Using TRNSYS Software of Hybrid Systems with PV-T

Energies ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6921
Author(s):  
Sebastian Pater
Keyword(s):  
Energy Production ◽  
Electric Energy ◽  
Electrical Energy ◽  
Climatic Conditions ◽  
One Year ◽  
Systems Simulation ◽  
Long Term Performance ◽  
Term Performance ◽  
The Impact

A hybrid photovoltaic-thermal collector (PV-T) with the capability to produce thermal energy and electrical energy simultaneously has attracted the attention of researchers, especially in terms of improving PV-T performance. This study analyses the work of four model installations with PV-T and other devices built in the transient systems simulation program. The novelty of this article lies in a long-term approach to the operation of PV-T panels under selected climatic conditions. Influence of the installation’s configuration on the obtained temperatures of solar cells, and, in consequence, on electric power generated by PV-T and the amount of heat produced during one year in a selected location is presented. Among others, the impact of the temperature coefficient of photovoltaic cells for long-term PV-T operation was analyzed in the paper. The results showed that the type of cell used may decrease the yearly electric energy production from PV-T even by 7%. On the other hand, intensification of the process of heat reception from PV-T using a heat pump increased this production by 6% in relation to the base model. The obtained research results indicate possible methods for improving the effectiveness of PV-T operation in a long-term aspect.

scholarly journals Pregnancy and Lactation Alter Vitamin A Metabolism and Kinetics in Rats under Vitamin A-Adequate Dietary Conditions

Nutrients ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 2853
Author(s):  
Yaqi Li ◽  
Ayasa Tajima ◽  
Floyd Mattie ◽  
Michael Green ◽  
A. Catharine Ross
Keyword(s):  
Vitamin A ◽  
Primary Source ◽  
Compartmental Analysis ◽  
Female Rats ◽  
Whole Body ◽  
Physiological Status ◽  
Female Rat ◽  
Limited Information ◽  
Pregnancy And Lactation ◽  
The Impact

Background: Vitamin A (VA) plays critical roles in prenatal and postnatal development; however, limited information is available regarding maternal VA metabolism during pregnancy and lactation. Objectives: We investigated the impact of pregnancy and lactation on VA metabolism and kinetics in rats, hypothesizing that changes in physiological status would naturally perturb whole-body VA kinetics. Methods: Eight-week old female rats (n = 10) fed an AIN-93G diet received an oral tracer dose of 3H-labeled retinol to initiate the kinetic study. On d 21 after dosing, six female rats were mated. Serial blood samples were collected from each female rat at selected times after dose administration until d 14 of lactation. Model-based compartmental analysis was applied to the plasma tracer data to develop VA kinetic models. Results: Our compartmental model revealed that pregnancy resulted in a gradual increase in hepatic VA mobilization, presumably to support different stages of fetal development. Additionally, the model indicates that during lactation, VA derived from dietary intake was the primary source of VA delivered to the mammary gland for milk VA secretion. Conclusion: During pregnancy and lactation in rats with an adequate VA intake and previous VA storage, the internal redistribution of VA and increased uptake from diet supported the maintenance of VA homeostasis.

scholarly journals LCA/LCC Model for Evaluation of Pump Units in Water Distribution Systems

Symmetry ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1181
Author(s):  
Mitar Jocanovic ◽  
Boris Agarski ◽  
Velibor Karanovic ◽  
Marko Orosnjak ◽  
Milana Ilic Micunovic ◽  
...  
Keyword(s):  
Life Cycle ◽  
Energy Consumption ◽  
Distribution Systems ◽  
Water Distribution ◽  
Water Distribution Systems ◽  
Ghg Emissions ◽  
Electric Energy ◽  
Electrical Energy ◽  
Pump Unit ◽  
The Impact

In this multidisciplinary research, an LCA/LCC model is developed for assessing the costs, energy consumption, and greenhouse gas (GHG) emissions during the pump unit lifecycles in drinking water distribution systems (WDS). The presented methodology includes the pump, motor, and variable frequency drive monitoring as a system (pump unit), through their life-cycle stages: the manufacturing stage, the exploitation stage, and the disposal stage at the end of their life-cycle. The developed model also analyses other processes such as the maintenance, testing, and reconstruction of the pump unit. Demonstration of the presented methodology was performed using the pump unit of an operating WDS system in different scenarios, in order to illustrate the proper application of this model. The obtained results show that the application of pump units is justified in terms of energy consumption. The results also show that 93%–94% of the consumed energy and the LCC costs are related to the pump operating costs, while the rest are related to auxiliary operations. The findings show that various countries can have considerably different prices of electrical energy and different GHG emissions that depend on the source of electric energy. The implemented model incorporates some of the symmetries that are commonly found in the mathematical models of water distribution systems. Finally, the results of pump unit exploitation within the WDS have been used to show the impact of such plants on different levels of energy consumption, GHG emissions, and LCC production.

scholarly journals STUDI PEMISAHAN BEBAN PENYULANG BARU SKTM GIS PANTAI INDAH KAPUK

2018 ◽  
Vol 9 (1) ◽  
pp. 16-25
Author(s):  
Redaksi Tim Jurnal
Keyword(s):  
Power Supply ◽  
Supply Voltage ◽  
Electric Energy ◽  
Electrical Energy ◽  
Power Supply Voltage ◽  
Xlpe Cable ◽  
Electric Power Supply ◽  
Energy Needs ◽  
Voltage Quality

With increasing energy needs of electricity for industry and new customers in the crowded settlements, especially along the coastal areas of Beautiful Kapok, readiness and availability of resources to increase the burden of customers need efforts and appropriate measures. One of the most easy and safe to transmit electrical energy is by Splitting the load. The aim in this study is to determine the way and site selection as well as calculate the imposition of new penyulang. The distribution of electric energy from the parent booths toward the consumers can do with the distribution of direct or indirect distribution. Via Penyulang 20 kV distribution with the selected cable channels-free cable is a requirement of the disorder, in an effort to increase the quality of the distribution. In the system of electric power supply, voltage general conditions let it send penyulang allowed (5%-10%) according to the standard PLN. While according to ANSI standard C84, paragraph 1 is (4% and-10%) under normal conditions. The current that flows through the penyulang must not exceed the limit of the ability distribution against the denseness of the load. So that the required voltage quality is better. As for who should be taken into account in determining the location of the new building of the penyulang is based on the Division of the burden, then choose the type of cable that well that is kind of XLPE cable 240 mm2 aluminum as a necessary investment.

scholarly journals Influence of supply voltage and frequency variations on the electrical equipment and power consumption in LV and MV distribution networks

Energetika ◽  
2020 ◽  
Vol 65 (4) ◽  
Author(s):  
Illia Diahovchenko ◽  
Nataliia Sushchenko ◽  
Anton Shulumei ◽  
Oleksandr Strokin
Keyword(s):  
Power Systems ◽  
Low Voltage ◽  
Supply Voltage ◽  
Electric Energy ◽  
Stochastic Theory ◽  
Electrical Equipment ◽  
Distribution Networks ◽  
Quality Parameters ◽  
Electric Energy Consumption ◽  
Frequency Variations

This paper is focused on the analysis of supply voltage and frequency quality in low voltage and medium voltage distribution power systems. The influence of supply voltage and frequency variations, within the limits defined in the valid standards, on the power network’s parameters has been evaluated using the stochastic theory and the statistical analysis methods. The circuit of RLC-load was considered for numerical evaluation. The probability distribution of supply voltage and frequency was defined and the suggestions on optimum voltage and frequency quality parameters regarding electric energy consumption, power losses and electrical equipment lifespan were given.

The Doctor Faustus Dossier

2018 ◽  
Author(s):  
Adrian Daub
Keyword(s):  
Twentieth Century ◽  
Los Angeles ◽  
Primary Source ◽  
Music And Literature ◽  
Twentieth Century Music ◽  
Private And Public ◽  
Doctor Faustus ◽  
Public Lives ◽  
Nazi Era ◽  
The Impact

Arnold Schoenberg and Thomas Mann, two towering figures of twentieth-century music and literature, both found refuge in the German-exile community in Los Angeles during the Nazi era. This complete edition of their correspondence provides a glimpse inside their private and public lives and culminates in the famous dispute over Mann's novel Doctor Faustus. In the thick of the controversy was Theodor Adorno, then a budding philosopher, whose contribution to the Faustus affair would make him an enemy of both families. Gathered here for the first time in English, the letters are complemented by diary entries, related articles, and other primary source materials, as well as an introduction that contextualizes the impact that these two great artists had on twentieth-century thought and culture.

Toxic Political Leadership and the Problems of Professionals in Free State Municipalities

2019 ◽  
Vol 48 (1) ◽  
Author(s):  
David Matheakuena Mohale
Keyword(s):  
Good Governance ◽  
Political Leadership ◽  
Primary Source ◽  
Free State ◽  
Audit Report ◽  
Theoretical Understanding ◽  
Number Of Factors ◽  
Auditor General ◽  
Appointed Officials ◽  
The Impact

The 2016–17 Audit Report by the Auditor General points to the deterioration in audit results of South African municipalities. This deterioration confirms the perennial dysfunctionality of municipalities, at least from the governance perspective. Corporate governance is a function of leadership. Municipal councils are, therefore, responsible for the overall performance of municipalities they lead. Sound regulatory framework, good plans, clear strategies, policies, and systems are inadequate if not supported by highly gifted and ethical leadership. The Auditor General’s Audit Report suggests that local government struggles the most in the area of ethics. The Principal-Agent Theory argues that appointed officials are more likely to subvert the interests of an organisation. However, this article argues that the primary source of problems in municipalities is a combination of ineptitude and unethical political leadership taking root. This conclusion is based on the empirical comparative cases of eight municipalities in the Free State Province.  The conduct of councillors makes it difficult to attract and retain professionals in municipalities, resulting in notable deficiencies in the delivery of services. Essentially, councillors are the root cause for governance failure in municipalities arising from a number of factors. Findings in this study contribute towards the understanding of the impact of leadership in the failure of municipalities to meet good governance and developmental objectives. Further, they deepen the theoretical understanding of the political-administrative interface.

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