Factors influencing generation times of spruce beetles in Alaska

1985 ◽  
Vol 15 (2) ◽  
pp. 438-443 ◽  
Author(s):  
Richard A. Werner ◽  
Edward H. Holsten
Keyword(s):  
Solar Radiation ◽  
Developmental Rate ◽  
Life Cycles ◽  
Direct Solar Radiation ◽  
Threshold Temperature ◽  
The South ◽  
The North ◽  
Generation Times ◽  
Standing Trees ◽  
One Year

Direct solar radiation to the bark surface of white spruce, Piceaglauca (Moench) Voss, is the primary environmental factor influencing the developmental rate of spruce beetles, Dendroctonusrufipennis (Kirby), in Alaska. A phloem threshold temperature of 16.5 °C is required to initiate the development of 1 year life cycle beetles. Tree location within a stand and stand aspect in relation to direct solar radiation determine which trees or areas of the tree support beetles with 1- and 2-year life cycles. Two-year cycles normally developed on the north and west sides of standing trees and the north and bottom sides of felled trees, which were characterized by an average phloem temperature of 10.6 °C. One-year cycles normally developed on the south sides of standing trees and the south and top sides of felled trees, which were characterized by an average phloem temperature of 16.5 °C.

scholarly journals A Study on Multi-Objective Parametric Design Tool for Surround-Type Movable Shading Device

2019 ◽  
Vol 11 (24) ◽  
pp. 7096
Author(s):  
Ho-Jeong Kim ◽  
Chang-Seok Yang ◽  
Hyeun Jun Moon
Keyword(s):  
Solar Radiation ◽  
Parametric Design ◽  
Design Tool ◽  
Direct Solar Radiation ◽  
The South ◽  
Winter Solstice ◽  
Performance Simulation ◽  
Multi Objective ◽  
The One ◽  
Shading Device

This study presents a multi-objective parametric design tool for four-axis surround-type movable shading device using solar position tracking in Seoul, South Korea. In order to explore large numbers of possible forms of shades, generic algorithms are utilized with real-time simulation of the performative criteria such as solar radiation, daylight glare probability (DGP), and solar shielding rate on window surface. This study outlines a workflow using a multi-objective engine called Octopus that runs within Grasshopper 3D, a parametric design tool, in addition to environmental performance simulation plug-in Ladybug. The workflow utilizes a performance-based design tool, which allows the designer to explore, sort, and filter solutions, and visually compare alternative solutions in terms of energy saving and indoor daylight quality in order to determine the optimal form of shade changing its shape every one hour. The result of deriving and analyzing the optimal shade shape through the genetic algorithm proposed in this study is as follows: On the one hand, on the summer solstice, shade shapes with shielding areas of almost 100% should be derived to achieve the most effective reduction of the direct solar radiation. The proposed movable shading device reduced direct solar radiation by 52.40% and 57.20% in the south- and east-facing windows, respectively. On the other hand, in winter when solar heat gain is important, the absence of sunshade is optimal in terms of heating load. However, in order to improve the indoor light environment, it is confirmed that it is possible to derive a certain shape of sunshade according to the sun’s trajectory. On the winter solstice, the problem of glare arises from 10:00 to 15:00 in the south and 10:00 in the east. Therefore, the proposed four-axis movable shading device can be configured to have a minimum protrusion length satisfying DGP less than 0.35 in winter.

Ocean Cruising: A Sailing Subculture

1992 ◽  
Vol 40 (2) ◽  
pp. 319-343 ◽  
Author(s):  
Jim Macbeth
Keyword(s):  
New Zealand ◽  
North Atlantic ◽  
South Pacific ◽  
The South ◽  
Fringing Reef ◽  
The North ◽  
Hurricane Season ◽  
The North Atlantic ◽  
One Year

Just after dawn, an English couple in their 30's haul up their anchor and motor across the stillness of Suva harbour. The hurricane season is approaching and they are embarking on the 2–3 week trip to Bay of Islands New Zealand for the southern summer. Three months earlier, as their yacht lay aground on the fringing reef of uninhabited Suvarov atoll, they wondered if they'd ever reach New Zealand. But, with the help of other cruisers and lucky tides their steel 36 footer was clear and safe in under 24 hours. What was to be a one year trip around the north Atlantic was now happily way off course in the South Pacific and likely to remain so for some time. That is just a glimpse of one small aspect of ocean cruising, the subculture of interest here. However, throughout the paper the ethnography of cruising is developed further. A model is proposed to show how individuals come to share the subculture ideology and then to participate in the lifestyle. Subsequently, 1 will place ocean cruising in the context of subculture theory by expanding the ethnography and relating cruising to other subcultures.

The French Army and Malian independence (1956–1961)

2013 ◽  
pp. 75-89 ◽  
Author(s):  
Vincent Joly
Keyword(s):  
Political Elite ◽  
Algerian War ◽  
The South ◽  
French Army ◽  
The North ◽  
French Military ◽  
Nuclear Tests ◽  
The Government ◽  
One Year ◽  
Independent Country

In Mali, as analyzed by Vincent Joly, military continuities led in 1961 to a real crisis. In January 1961 Modibo Keïta, the President of the independent country, enforced the evacuation of the remaining French troops. The worries of the Malian government had been intensified by French activities during the Algerian War and by French nuclear tests in the south of the Sahara. Under the pretext of Malian anger over French behaviour during the split of the Federation of Mali one year earlier, the government in Bamako – defender of increasingly ‘radical’ positions – gladly used this occasion to get rid of structures that effectively constituted a counterweight in the country. The new Malian political elite were particularly distrustful of the presence of the French military forces because French officials maintained close relations to army veterans and to the nomadic populations in the north of the country. Joly interprets the process leading to the 1961 crisis as characteristic of the complex decolonization processes, in which the French army had its own clients and networks in the now-independent countries.

Euphausiid life cycles and distribution around South Georgia

1990 ◽  
Vol 2 (1) ◽  
pp. 43-52 ◽  
Author(s):  
Peter Ward ◽  
Angus Atkinson ◽  
Julie M. Peck ◽  
Andrew G. Wood
Keyword(s):  
Life Cycle ◽  
Life Histories ◽  
Life Cycles ◽  
Seasonal Migration ◽  
Frequency Data ◽  
Oceanic Water ◽  
Limited Evidence ◽  
South Georgia ◽  
The North ◽  
One Year

Euphausiid life histories and distribution in the vicinity of South Georgia were studied from a series of samples taken in April 1980, November–December 1981, and July–August 1983. Size frequency data indicated a two-year life cycle for Euphausia frigida and the possibility of a three-year cycle for E. triacantha. The genus Thysanoessa was represented by a mixture of T. macrura and the dominant T. vicina. A one-year life cycle is proposed for the latter but that of the former is unknown. Spawning in E. frigida and to a lesser extent Thysanoessa spp. commenced as early as July and euphausiid calyptopes were a feature of the plankton for much of the year. E. superba eggs were found in low abundance over the shelf to the north of the island, but no hatched larvae were found. Behaviour patterns such as diurnal and seasonal migration partially confounded attempts to relate euphausiid distribution to environmental features. However calyptopes of most species, were generally more abundant in oceanic water deeper than 500 m and there was limited evidence that in August, E. frigida had commenced spawning in the colder part of the survey area.

DIVERSITY OF CRYPTOGAMIC PLANTS AND FUNGI IN “EVOLUTION CANYON”, NAHAL OREN, MOUNT CARMEL NATURAL PRESERVE, ISRAEL

1995 ◽  
Vol 43 (4) ◽  
pp. 367-383 ◽  
Author(s):  
S.P. Wasser ◽  
E. Nevo ◽  
O.N. Vinogradova ◽  
I.L. Navrotskaya ◽  
I.A. Ellanskaya ◽  
...  
Keyword(s):  
Solar Radiation ◽  
Research Program ◽  
The South ◽  
Valley Bottom ◽  
Lichenicolous Fungi ◽  
The North ◽  
Evolution Canyon ◽  
Infraspecific Taxa

The diversity of cryptogamic plants and fungi has been studied, in the context of a research program of biodiversity across phylogeny, at the “Evolution Canyon” microsite. Lower Nahal Oren, Mount Carmel Natural Preserve, Israel. The opposite slopes of Evolution Canyon display dramatic biotic contrasts due to higher (up to 300%) solar radiation on the south-facing slope (S-slope) which is warmer, drier, and climatically more fluctuating than the north-facing slope (N-slope). Diversity of cryptogamic plants and fungi (198 species and intraspecific taxa) at Evolution Canyon is considerable. The list includes 46 taxa of Cyanophyta, 10 of Chlorophyta, 3 of Euglenophyta, 1 of Bacillariophyta, 29 of lichens, 2 of lichenicolous fungi, 59 of soil micromycetes, 39 of Agaricales s.l., and 9 of mosses. Fifty species and infraspecific taxa are new for the biota of Israel, among them 22 taxa of algae, 9 of micromycetes, 8 of Agaricales s.l., 9 of lichens, and 2 of lichenicolous fungi. Some of them are new for the biota of Asia. While fungi (especially Agaricales s.l.) and mosses primarily range on the more wet and humid “temperate European” N-facing slope, or in the valley bottom (mosses), algae, primarily due to the number of cyanobacteria, predominate on the warm and dry “tropical African” S-facing slope.

The cold temperate zone in Chilean seas

1960 ◽  
Vol 152 (949) ◽  
pp. 631-633 ◽  
Keyword(s):  
Temperate Zone ◽  
Tierra Del Fuego ◽  
The South ◽  
Chilean Coast ◽  
The North ◽  
One Year ◽  
Warm Temperate ◽  
Present Meeting

The results of the Lund University Chile Expedition in 1948-49 throw some light upon the delimitation and ecology of the cold temperate areas in the Chilean seas, and therefore it seems justified to present a very brief summary to the present meeting. The expedition was organized by Professor Hans Brattström and myself and worked in Chile for almost one year from September 1948 to August 1949. We mainly concentrated upon marine work and collected samples in various localities along the whole Chilean coast from Arica to Tierra del Fuego. Our main base, however, was in Puerto Montt in about 41½° S and most of our work was carried out in the waters around the Island of Chiloé, between Puerto Montt in the north and the Chonos Islands in the south, i. e. just in the area where the border between the northern warm temperate and the southern cold temperate or antiboreal zoogeographical regions is supposed to lie. The working-up of our collections is still far from complete. The published records now comprise about 2000 pages, another 300 to 400 are in print and many reports are in preparation.

scholarly journals Education in Colonial Sudan, 1900–1957

2017 ◽  
Author(s):  
Iris Seri-Hersch
Keyword(s):  
Private Schools ◽  
The South ◽  
Government School ◽  
The North ◽  
Government Education ◽  
School Network ◽  
Arabic And English ◽  
One Year ◽  
Colonial Government ◽  
Arabic Speaking

In the first half of the 20th century, Sudan, which included the territories of present-day Sudan and South Sudan, was ruled by a dual colonial government known as the Anglo-Egyptian Condominium (1899–1956). Britain was the senior partner in this administration, Egypt being itself politically and militarily subordinated to Britain between 1882 and 1956. During most of the colonial period, Sudan was ruled as two Sudans, as the British sought to separate the predominantly Islamic and Arabic-speaking North from the multireligious and multilingual South. Educational policy was no exception to this: until 1947, the British developed a government school system in the North while leaving educational matters in the hands of Christian missionaries in the South. In the North, the numerically dominant government school network coexisted with Egyptian schools, missionary schools, community schools, and Sudanese private schools. In the South, schools were established by the Anglican Church Missionary Society, the Roman Catholic Verona Fathers, and the American Presbyterian Mission. Whereas Arabic and English were the mediums of instruction in Northern schools, the linguistic situation was more complicated in the South, where local vernaculars, English and Romanized Arabic were used in missionary schools. The last colonial decade (1947–1957) witnessed a triple process of educational expansion, unification, and nationalization. Mounting Anglo-Egyptian rivalries over the control of Sudan and the polarization of Sudanese nationalists into “pro-British” independentists and “pro-Egyptian” unionists led the British authorities in Khartoum to boost government education while giving up the policy of separate rule between North and South. In practice, educational unification of the two Sudanese regions meant the alignment of Southern curricula on Northern programs and the introduction of Arabic into Southern schools, first as a subject matter, then as a medium of instruction. Missionary and other private schools were nationalized one year after Sudan gained independence from Britain and Egypt (1956).

Long-term Cyclic Variations of Prominences, Green and Red Coronae over Solar Cycles

2000 ◽  
Vol 179 ◽  
pp. 201-204
Author(s):  
Vojtech Rušin ◽  
Milan Minarovjech ◽  
Milan Rybanský
Keyword(s):  
Emission Lines ◽  
High Latitudes ◽  
Green Line ◽  
Solar Cycles ◽  
The South ◽  
Coronal Emission ◽  
Local Maxima ◽  
The North ◽  
Cyclic Variations

AbstractLong-term cyclic variations in the distribution of prominences and intensities of green (530.3 nm) and red (637.4 nm) coronal emission lines over solar cycles 18–23 are presented. Polar prominence branches will reach the poles at different epochs in cycle 23: the north branch at the beginning in 2002 and the south branch a year later (2003), respectively. The local maxima of intensities in the green line show both poleward- and equatorward-migrating branches. The poleward branches will reach the poles around cycle maxima like prominences, while the equatorward branches show a duration of 18 years and will end in cycle minima (2007). The red corona shows mostly equatorward branches. The possibility that these branches begin to develop at high latitudes in the preceding cycles cannot be excluded.

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