Effect of thermal diffusivity of insulating materials on room free-float temperature with façade external insulation

External insulation of building façade is widely used to reduce heating energy demand in buildings. Usually, its design concerns only thermal transmittance, while transient thermal behaviour is commonly addressed only as dumping factor or time lag of outdoor heat wave. During summer, in many mild climates, outdoor daily mean temperature is close to comfort temperature. Yet, even though mean heat transfer through building envelope is null, heating during daytime may lead to positive cooling loads or discomfort temperatures in non-conditioned rooms. In residential buildings internal loads are usually very low, so the most relevant loads are heat transfer though outer facades. Moreover, where there is no cooling, wall dumping factor is not meaningful to evaluate the thermal performance of wall insulation, as it is referred to constant indoor temperature. In this framework, a model of a room with a single outer wall has been developed to study the effect of insulating material on free-float temperature. Transient heat transfer through the envelope as well as through inner walls is considered to model indoor air temperature. Different localities in Italy and commonly used insulating materials are considered

Rain event properties at the source of the Blue Nile River

In the present study, spatial and temporal patterns of rain event properties are analysed. These event properties are rain event depth, event duration, mean event rain rate, peak rain rate and the time span between two consecutive rain events which is referred to as inter-event time (IET). In addition, we assessed how rain event properties change when the period over which rainfall data is aggregated changes from 1 to 6 min and when the minimum inter-event time (MIT) changes from 30 min to 8 h. Rainfall data is obtained from a field campaign in two wet seasons of June–August (JJA) of 2007 and 2008 in Gilgel Abbay watershed that is situated at the source basin of the Upper Blue Nile River in Ethiopia. The rainfall data was automatically recorded at eight stations. The results revealed that rain event depth is more related to peak rain rate than to event duration. At the start and towards the end of the wet season, the rain events have larger depth with longer duration and longer IET than those in mid-season. Event rain rate and IET are strongly related to terrain elevation. Sekela which is on a mountain area has the shortest IET while Bahir Dar which is at the south shore of Lake Tana has the longest IET. The period over which rainfall data is aggregated significantly affected the values of rain event properties that are estimated using relatively small value (30 min) of MIT but its effect diminished when the MIT is increased to 8 h. It is shown that increasing the value of MIT has the largest effect on rain event properties of mountain stations that are characterised by high rainfall intermittency

Ecological bases for an I.P.M. programme for the cotton boll weevil (Anthonomus grandis Boh.) in São Paulo State, Brazil.

Since the boll weevil, Anthooomus granQis Boh., was detected io cotton üelds in São Paulo state, Brazil, in 1983, maoy ecological aspects have been studied aimiog the establishment of some Integrated Pest Maoegement (I.P.M.) strategies for its contraI. Also, many ecoloçical and behavioural differences were detected in comparison to omer conon agroecosystems, principally in the U.S.A. This situation allowed to recommend ao I.P.M programme based 00 vegetable traps, crop weekly mooitoriog, destructioo of cotton píant stalks as soon as conon was harvested and utiJization of aggregating pheromone and seletive chemicaJ insecticides

Aspectos biológicos e de comportamento dos principais parasitos de Anthonomus grandis Boh. (Coleoptera: Curculionidae), em Campinas-SP.

Aspectos da biologia e do comportamento de quatro espécies de himenópteros ectoparasitos de Anthonomus grandis Boh., o bicudo do algodoeiro, ocorrendo na região de Campinas, SP, foram estudados em condições de laboratório. Bracon oulgaris Ashmead (Hymenoptera, Braconidae) revelou grande adaptabilidade às condições artificiais de criação. As fêmeas deste braconídeo ovipõem em média, 2,08 ovo&,hospedeiro; o período de incubação dos ovos variou de 24 a 36 horas; as larvas passaram por quatro estádios, completando seu desenvolvimento em 4,0 dias, tempo igualmente observado para o estágio pupal. A longevidade de adultos acasalados foiem média, 41,11 dias para fêmeas e 31,72 para machos. Durante a entressafra, na ausência de A. grandis, larvas de último estádio de Plodia interpunctella (Hueb.) (Lepidoptera, Pyralidae) foram usadas como hospedeiro alternativo, revelando-se adequadas. Informações de outras três espécies de parasitos, Bracon sp., Catoloccus grandis (Burks) (Hymenoptera, Pteromalidae) e Eupelmus cushmani (Hymenoptera, Eupelmidae) também são apresentadas

Effect of three larval diets on the development of the armyworm, Spodoptera latifascia Walker, 1856 (Noctuidae, Lepidoptera)

Some biological effects of feeding larvae of the armyworm Spodoptera latifascia with leaves of three plant species (cotton, soybean and lettuce) have been studied. Some indicative measurements were utilized to determine the host suitability of these three plant species. Cotton leaves (Gossypium hirsutum) were found to be better than soybean (Glycine max) for the development and growth of this insect. Lettuce leaves (Lactuca sativa) were incapable of sustaining this insect. Moreover, the stress of the latter diet was associated with a latent microbial disease, a mixed infection caused by Vairimorpha sp. and a nuclear polyhedrosis virus (NPV). Cotton leaves can be recommended as a suitable diet for mass rearing of this insect species. Due to recent outbreks of S. latifascia observed in the States of São Paulo, Santa Catarina and Paraná and because of the frequent applications of wide spectrum chemical insecticides, it can be expected that this insect will soon become one of the important pests threatening cotton and other economic plantations in Brazil.17718

Tamanho mínimo de amostra de plantas e frutos do algodoeiro para monitoramento das populações de Anthonomus grandis Boh. (Coleoptera: Curculionidae).

Dois modelos estatísticos foram desenvolvidos visando determinar o tamanho mínimo de amostra para monitoramento de populações do bicudo do algodoeiro, Anthonomus grandis Boh. (Coleoptera: Curculionidae). A amostra consistiu no número mínimo de plantas e/ou frutos do algodoeiro avaliados para se detectar as densidades populacionais do inseto próximas ao limiar econômico, considerando-se ainda a área da cultura a ser monitorada

Chaos and Noise in a Truncated Toda Potential

Results are reported from a numerical investigation of orbits in a truncated Toda potential which is perturbed by weak friction and noise. Two significant conclusions are shown to emerge: (1) Despite other nontrivial behaviour, configuration, velocity, and energy space moments associated with these perturbations exhibit a simple scaling in the amplitude of the friction and noise. (2) Even very weak friction and noise can induce an extrinsic diffusion through cantori on a time scale much shorter than that associated with intrinsic diffusion in the unperturbed system.Comment: 10 pages uuencoded PostScript (figures included), (A trivial mathematical error leading to an erroneous conclusion is corrected