The determinants of output losses during the Covid-19 pandemic

AbstractTravelers along the Onne-seaport to Eleme-junction road corridor in the hub of the oil and gas industry in Port-Harcourt, Nigeria, have continued to experience very serious traffic congestion travel time delays, culminating into loss of man-hours and declining productivity. This study estimated the economic cost of traffic congestion travel time delay along the corridor, with a view to providing economic justification for developing traffic management policies and road infrastructure, to remedy it. A mixed research approach was adopted in which data was sourced through field survey and from secondary sources. The gross output model was used to estimate the output losses occasioned by productive time losses related to traffic congestion. The study established that the average daily traffic congestion travel time delay along the traffic corridor by travelers in trucks, car, bus and taxi modes are 104.17 minutes, 46.60 minutes, 58.5 minutes and 56.4 minutes respectively. The estimated daily aggregate economic cost of output losses associated with traffic congestion time delay on the corridor is 46049809.8 naira (210923.5USD) for all modes. This justifies any investment in traffic congestion remedial strategies along the route.

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Wind turbine icing characteristics and icing-induced power losses to utility-scale wind turbines

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2111461118 ◽

2021 ◽

Vol 118 (42) ◽

pp. e2111461118

Author(s):

Linyue Gao ◽

Hui Hu

Keyword(s):

Wind Turbines ◽

Power Output ◽

Turbine Blades ◽

Digital Camera ◽

Unmanned Aircraft ◽

Ice Accretion ◽

Power Losses ◽

Field Campaign ◽

Output Losses ◽

Utility Scale

A field campaign was carried out to investigate ice accretion features on large turbine blades (50 m in length) and to assess power output losses of utility-scale wind turbines induced by ice accretion. After a 30-h icing incident, a high-resolution digital camera carried by an unmanned aircraft system was used to capture photographs of iced turbine blades. Based on the obtained pictures of the frozen blades, the ice layer thickness accreted along the blades’ leading edges was determined quantitatively. While ice was found to accumulate over whole blade spans, outboard blades had more ice structures, with ice layers reaching up to 0.3 m thick toward the blade tips. With the turbine operating data provided by the turbines’ supervisory control and data acquisition systems, icing-induced power output losses were investigated systematically. Despite the high wind, frozen turbines were discovered to rotate substantially slower and even shut down from time to time, resulting in up to 80% of icing-induced turbine power losses during the icing event. The research presented here is a comprehensive field campaign to characterize ice accretion features on full-scaled turbine blades and systematically analyze detrimental impacts of ice accumulation on the power generation of utility-scale wind turbines. The research findings are very useful in bridging the gaps between fundamental icing physics research carried out in highly idealized laboratory settings and the realistic icing phenomena observed on utility-scale wind turbines operating in harsh natural icing conditions.

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Performance evaluation of GaN and Si based driver circuits for a SiC MOSFET power switch

International Journal of Power Electronics and Drive Systems (IJPEDS) ◽

10.11591/ijpeds.v12.i3.pp1293-1303 ◽

2021 ◽

Vol 12 (3) ◽

pp. 1293

Author(s):

Martin J. Carra ◽

Hernan Tacc ◽

Jose Lipovetzky

Keyword(s):

Silicon Carbide ◽

Performance Evaluation ◽

Gallium Nitride ◽

Switching Process ◽

Control Power ◽

Power Switch ◽

Power Switches ◽

Gate Driver ◽

Output Losses

<p>Silicon Carbide (SiC), new power switches (PSW) require new driver circuits which can take advantage of their new capabilities. In this paper a novel Gallium Nitride (GaN) based gate driver is proposed as a solution to control SiC power switches. The proposed driver is implemented and is performance compared with its silicon (Si) counterparts on a hard switching environment. A thorough evaluation of the energy involved in the switching process is presented showing that the GaN based circuit exhibits similar output losses but reduces the control power needed to operate at a specified frequency.</p>

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A NOTE ON BANKING AND HOUSING CRISES AND THE STRENGTH OF RECOVERIES

Macroeconomic Dynamics ◽

10.1017/s1365100515000164 ◽

2015 ◽

Vol 20 (7) ◽

pp. 1924-1933 ◽

Cited By ~ 4

Author(s):

Jens Boysen-Hogrefe ◽

Nils Jannsen ◽

Carsten-Patrick Meier

Keyword(s):

Banking Crises ◽

Advanced Economies ◽

Output Losses ◽

Bounce Back

We investigate whether recoveries following normal recessions differ from recoveries following recessions that are associated with either banking crises or housing crises. Using a parametric panel framework that allows for a bounce-back in the level of output during the recovery, we find that normal recessions are followed by strong recoveries in advanced economies. This bounce-back is absent following recessions associated with banking crises and housing crises. Consequently, the permanent output losses of recessions associated with banking crises and housing crises are considerably larger than those of normal recessions.

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Input Specificity and the Propagation of Idiosyncratic Shocks in Production Networks *

The Quarterly Journal of Economics ◽

10.1093/qje/qjw018 ◽

2016 ◽

Vol 131 (3) ◽

pp. 1543-1592 ◽

Cited By ~ 183

Author(s):

Jean-Noël Barrot ◽

Julien Sauvagnat

Keyword(s):

Natural Disasters ◽

Important Determinant ◽

Market Value ◽

Production Networks ◽

Firm Level ◽

Point Estimates ◽

Idiosyncratic Shocks ◽

Output Losses

Abstract This article examines whether firm-level idiosyncratic shocks propagate in production networks. We identify idiosyncratic shocks with the occurrence of natural disasters. We find that affected suppliers impose substantial output losses on their customers, especially when they produce specific inputs. These output losses translate into significant market value losses, and they spill over to other suppliers. Our point estimates are economically large, suggesting that input specificity is an important determinant of the propagation of idiosyncratic shocks in the economy.

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Laser output losses with intra-cavity etalons

Optics & Laser Technology ◽

10.1016/0030-3992(75)90022-5 ◽

1975 ◽

Vol 7 (2) ◽

pp. 63-64

Author(s):

D. Fua ◽

G. Magyar

Keyword(s):

Laser Output ◽

Output Losses

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THE ECONOMIC IMPACT OF SOVEREIGN DEFAULTS IN LATIN AMERICA 1870-2012

Revista de Historia Económica / Journal of Iberian and Latin American Economic History ◽

10.1017/s0212610916000136 ◽

2016 ◽

Vol 35 (1) ◽

pp. 81-104

Author(s):

Tjeerd Menno Boonman

Keyword(s):

Latin American ◽

Sovereign Debt ◽

Gdp Growth ◽

Domestic Economy ◽

Real Gdp ◽

Output Losses ◽

Run Up ◽

Sovereign Defaults ◽

The Impact ◽

Latin American Countries

ABSTRACTThis article analyzes sovereign debt defaults in four Latin American countries—Argentina, Brazil, Chile and Mexico—for the period 1870-2012. The impact of sovereign defaults on real GDP growth is generally short-lived, while the impact in terms of output losses is deep and lasts long. Defaults in the period 1972-2012 show a deep and long-lasting impact compared to defaults in earlier periods. Moreover, the length of the contraction that follows a default is associated with favourable international conditions in the run-up to a default, while the depth of the contraction is associated with an expansive domestic economy in the run-up to a default. The results fit with boom–bust theories and sudden stop models.

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