A Method of Comparing the Performances of Commercial Aircraft

1934 ◽  
Vol 38 (282) ◽  
pp. 477-480 ◽  
Author(s):  
M. Langley

Major Green in his paper has given prominence to a subject which is now becoming of wide interest and great commercial importance. A method of assessing the economic value of speed is very desirable and Major Green has attempted to do this by means of an index figure.I would like to put forward a method which, whilst it does not provide a datum or index figure, offers a ready method of comparing two or more machines, taking into account those features of the aircraft which are of economic importance. It must be accepted that the geographical and political features of different routes, time-tables, and other such extra-to-aircraft items could be included in any method of comparison without the use of an empiric formula, the relative importance of whose terms would be largely a matter of opinion. Further, this method is based not on subsidy earning but profit earning capacity.

Author(s):  
Celal Taşdoğan ◽  
Bilgen Taşdoğan

Turkey has realized high growth rates during the period of 2002-2011, except in 2008 and 2009 years. It is thought that the rapidly growing in the country may cause a lot of environmental damage, especially air pollution problems. In other words, the productive sectors have produced two outputs which are economic value added and air pollutants. This study used input output matrixes are to find out the strategically important sectors as it is known key sectors and weak sectors caused the environmental effects in the country. For this purpose, it has been tried to investigate air pollutant quantities which caused by the production process of the sectors in the period of 2002-2011 and performed the input-output tables for Turkey constructed in the World Input Output Database (WIOD) Project. These input-output tables include the emission satellite accounts, which are CO2 emissions and other air pollutants, respectively N2O, CH4, N2O, NOx, SOx, CO, NMVOC and NH3, disaggregated for the 34 sectors. It is expected that the outcomes of the study may contribute to sustainable growth debates and environmental policy implementations in Turkey.


1995 ◽  
Vol 19 ◽  
pp. 9-12
Author(s):  
O. Meland

AbstractThe objective of any well designed progeny test programme is to identify those individuals that have inherited the favourable genes from his parents. Bulls that enter a progeny test programme have been highly selected on a set of selection criteria. The criteria vary among organizations based upon their breeding philosophy and their prediction of the future economic value of various traits. The accuracy of choosing among this highly selected group is quite low. Increasing the accuracy of selection before progeny testing is the greatest potential application of genetic marker technology. Markers associated with traits of importance can greatly enhance traditional selection methods by increasing the prospect of an individual having the desired characteristics. Genetic marker-assisted selection can greatly increase the actual genetic merit of traits of economic importance


Challenges ◽  
2020 ◽  
Vol 11 (2) ◽  
pp. 32
Author(s):  
Sarath M. Vega Gutierrez ◽  
Javier F. Illescas Guevara ◽  
Claudia C. Andersen ◽  
Jose Koechlin von Stein ◽  
Seri C. Robinson

Most of the research related to Peruvian Amazon fungi is focused on edible mushrooms and pathogens. Other important fungi, such as the spalting type (decay fungi that pigment wood internally), are not broadly studied, as most of them do not produce fruiting bodies and can be difficult to locate. Spalting fungi, however, are of broad economic importance due to their ability to produce pigments that enhance wood aesthetics, resulting in an increased economic value. In order to begin understanding the diversity of spalting fungi within certain regions of the Amazon, a sampling of downed trees and branches (through the opening of the xylem to identify potential pigmenting and zone line producing fungi) was done in the district of Las Piedras, Madre de Dios, Peru. Fungi suspected of causing internal pigment and zone lines were collected, cultured, isolated, and sequenced. The species found belonged to the orders Helotiales, Xylariales, Hypocreales, Russulales, Polyporales, Botryosphaeriales and two specimens of the class Leotiomycetes. The fungi collected produced pigments or zone lines in wild conditions and all of them were capable of wood decomposition. Interestingly, these are the same orders and genera as North American spalting fungi, which may indicate a correlation within species that pigment wood. The results obtained start a specific database of spalted fungi in the Amazon and, with it, help support an effort to increase the forest value of ecosystems primarily used for a few high-valued tree species.


1955 ◽  
Vol 87 (9) ◽  
pp. 400-406 ◽  
Author(s):  
D. G. Harcourt ◽  
R. H. Backs ◽  
L. M. Cass

Cabbage and related crops are attacked every year throughout Ontario by caterpillars of three species, namely, the imported cabbageworm, Pieris rapae (L.), the diamondback moth, Plutella maculipennis (Curt.), and the cabbage looper, Trichoplusia ni (Hbn.). The imported cabbageworm is generally regarded as the most abundant of the three species and is reported as doing damage of considerable economic importance each year. The cabbage looper does not occur in large numbers until late in the season, but in most years it is believed to be second only in importance to the imported cabbageworm. The diamondback moth is generally considered to be much less important than the other two species (Caesar, 19i8). As previously reported (Matthewman et al., 1952), these beliefs were not borne our by observations of field populations at Ottawa in 1950. Whereas populations of the cabbage looper were strikingly low, those of the diamondback moth were much higher than the literature indicated. This paper is a summary of four seasons' experiments, 1951-1954, undertaken to assess the abundance and relative importance of the three species in eastern Ontario.


Oryx ◽  
2013 ◽  
Vol 47 (3) ◽  
pp. 381-388 ◽  
Author(s):  
Andrés M. Cisneros-Montemayor ◽  
Michele Barnes-Mauthe ◽  
Dalal Al-Abdulrazzak ◽  
Estrella Navarro-Holm ◽  
U. Rashid Sumaila

AbstractAmid declining shark populations because of overfishing, a burgeoning shark watching industry, already well established in some locations, generates benefits from shark protection. We compile reported economic benefits at shark watching locations and use a meta-analytical approach to estimate benefits at sites without available data. Results suggest that, globally, c. 590,000 shark watchers expend > USD 314 million per year, directly supporting 10,000 jobs. By comparison, the landed value of global shark fisheries is currently c. USD 630 million and has been in decline for most of the past decade. Based on current observed trends, numbers of shark watchers could more than double within the next 20 years, generating > USD 780 million in tourist expenditures around the world. This supports optimistic projections at new sites, including those in an increasing number of shark sanctuaries established primarily for shark conservation and enacted in recognition of the ecological and economic importance of living sharks.


2015 ◽  
Vol 12 (1) ◽  
pp. 25-29
Author(s):  
Michal Beniak ◽  
Michal Žabka

Abstract Many ecosystem services do not pass through markets. Therefore, the benefits which ecosystems provide to society are largely unrecorded. Fast-growing woody crops represent a quite new and still insufficiently explored ecosystem of agricultural land which has a potential to provide several utility functions. It may contribute to satisfaction of human needs and may enhance regional health. The goal of this paper was to detect the socio-economic importance of associated spontaneous vegetation in plantations of the energy crops (hybrids of the genera Salix) and to compare it with the socio-economic importance of adjacent permanently cultivated agricultural field. There was examined the therapeutic, melliferous, feed, allergenic and toxic potential of undergrowth for each experimental plot inside the SRC plantations. The research was carried out on the agricultural land formerly used for growing cereals and root crops – the research base Kolíňany. Our results showed that energy plantation understoreys can be assumed to be the better option for contribution to the total socio-economic value of a region than agricultural fields.


2021 ◽  
Vol 3 (2) ◽  
Author(s):  
Tanuja N. Bankar ◽  
Mudasir A. Dar ◽  
Radhakrishna S. Pandit

Pigments play an essential role in imparting colors to the various organs of invertebrates particularly, insects. Genetic evolution and adaptive pigmentation of invertebrates have been studied which depicted that insect colors respond to the climatic changes. The physical, chemical and structural properties of insect pigments are being studied by researchers for years to elucidate their evolutionary aspects of physiology, metabolism, and economic importance for human welfare. Color development in insects varies within the species of different genera. In this state-of-the-art literature review, we discuss the variety of pigments other than visual ones found in different species of insects. The review also highlights the potential benefits or functions of pigments to insects.


Polar Record ◽  
2012 ◽  
Vol 49 (4) ◽  
pp. 381-391 ◽  
Author(s):  
Bjorn L. Basberg ◽  
Robert K. Headland

ABSTRACTSealing was the first exploitative industry in the Antarctic region. Throughout the 19th century it was characterised by large fluctuations in catches and shifts in hunting grounds as seals were almost exterminated in several locations. This paper reviews the historical literature on this industry. In particular it reviews sources and data that relate to its economic importance. So far, no one has succeeded in indicating the aggregate economic value of the industry. The main aim, therefore, is to investigate new data, especially on market prices that will enable a more accurate assessment of the significance of the industry.


1974 ◽  
Vol 19 (1) ◽  
pp. 93-105 ◽  
Author(s):  
T. H. Jackson ◽  
Y. A. Mansour

SUMMARYNinety-six lamb carcasses drawn from six batches of lambs commercially consigned to an abattoir were analysed for characteristics which may affect their economic value. From each batch carcasses were selected in equal numbers into two classes of ‘good’ or ‘poor’ conformation according to traditional standards. Carcasses selected for ‘good’ conformation were heavier (P<0·05) and fatter (P<0·05), slightly shorter in carcass length and hind leg length (P<0·05), greater in circumference (P<0·001) and width (P<0·001) of the hind leg, slightly greater in muscle weight (P<0·05) but no greater in bone weight than those of poor conformation. The yield of prime retail joints was similar in the two conformation classes but the ‘good’ conformation class had a higher proportion of loin and rib joints and lower proportion of hind leg joint (P < 0·01) although these differences were not considered to be of commercial importance. There was a lower proportion of the carcass fatty tissue in the hind leg joint of the ‘good’ conformation class (P < 0·05). Muscle-to-bone ratio and area of ‘eye muscle’ (M. longissimus thoracis) appeared to be little affected by selecting for conformation differences. Depth of fleshing as indicated by the weight of muscle in the hind leg per 10 cm length, was 40 g (6%) heavier in the carcasses of the ‘good’ conformation class. This contrasted with the much greater differences, between batches, of 290 g (40 to 50%). Between batches there were significant differences for all the measures taken except the yield of preferred retail cuts. In the main the batch differences were greater and commercially more important than the conformation class differences.


Author(s):  
Natalia Munteanu

The economic value of leaf-rolling weevils of Moldova Republic and their distribution on groups of wreckers of kidneys, leaves and generative organs are given. Only 8 % among the revealed beetles’ species actually harm to plants, other species do not cause special harm, being potential wreckers or indifferent. Dans le travail on donne l’importance économique des scarabées Rhynchitidae et Attelabidae (Coleoptera) et leur distribution selon les groupes des saboteurs des bourgeons, feuille et organismes génératifs. En réalité seulement 8 % parmi les espèces révélés Rhynchites et Attelabides causent des préjudices aux plantes, les autres espèces ne causent pas un dommage spécial, en étant les saboteurs potentiels ou indifférent.


Sign in / Sign up

Export Citation Format

Share Document