Analysis of cool roof coatings for residential demand side management in tropical Australia

Cool roof coatings have a beneficial impact on reducing the heat load of a range of building types, resulting in reduced cooling energy loads. This study seeks to understand the extent to which cool roof coatings could be used as a residential demand side management (DSM) strategy for retrofitting existing housing in a constrained network area in tropical Australia where peak electrical demand is heavily influenced by residential cooling loads. In particular this study seeks to determine whether simulation software used for building regulation purposes can provide networks with the ‘impact certainty’ required by their DSM principles. The building simulation method is supported by a field experiment. Both numerical and experimental data confirm reductions in total consumption (kWh) and energy demand (kW). The nature of the regulated simulation software, combined with the diverse nature of residential buildings and their patterns of occupancy, however, mean that simulated results cannot be extrapolated to quantify benefits to a broader distribution network. The study suggests that building data gained from regulatory simulations could be a useful guide for potential impacts of widespread application of cool roof coatings in this region. The practical realization of these positive impacts, however, would require changes to the current business model for the evaluation of DSM strategies. The study provides seven key recommendations that encourage distribution networks to think beyond their infrastructure boundaries, recognising that the broader energy system also includes buildings, appliances and people.

Parameter estimation of a two-horizon soil profile by combining crop canopy and surface soil moisture observations using GLUE

Estimation of soil parameters by inverse modeling using observations on either surface soil moisture or crop variables has been successfully attempted in many studies, but difficulties to estimate root zone properties arise when heterogeneous layered soils are considered. The objective of this study was to explore the potential of combining observations on surface soil moisture and crop variables - leaf area index (LAI) and above-ground biomass for estimating soil parameters (water holding capacity and soil depth) in a two-layered soil system using inversion of the crop model STICS. This was performed using GLUE method on a synthetic data set on varying soil types and on a data set from a field experiment carried out in two maize plots in South India. The main results were (i) combination of surface soil moisture and above-ground biomass provided consistently good estimates with small uncertainity of soil properties for the two soil layers, for a wide range of soil paramater values, both in the synthetic and the field experiment, (ii) above-ground biomass was found to give relatively better estimates and lower uncertainty than LAI when combined with surface soil moisture, especially for estimation of soil depth, (iii) surface soil moisture data, either alone or combined with crop variables, provided a very good estimate of the water holding capacity of the upper soil layer with very small uncertainty whereas using the surface soil moisture alone gave very poor estimates of the soil properties of the deeper layer, and (iv) using crop variables alone (else above-ground biomass or LAI) provided reasonable estimates of the deeper layer properties depending on the soil type but provided poor estimates of the first layer properties. The robustness of combining observations of the surface soil moisture and the above-ground biomass for estimating two layer soil properties, which was demonstrated using both synthetic and field experiments in this study, needs now to be tested for a broader range of climatic conditions and crop types, to assess its potential for spatial applications. (C) 2012 Elsevier B.V. All rights reserved.

On the strategic equivalence of multiple-choice test scoring rules

A disadvantage of multiple-choice tests is that students have incentives to guess. To discourage guessing, it is common to use scoring rules that either penalize wrong answers or reward omissions. These scoring rules are considered equivalent in psychometrics, although experimental evidence has not always been consistent with this claim. We model students' decisions and show, first, that equivalence holds only under risk neutrality and, second, that the two rules can be modified so that they become equivalent even under risk aversion. This paper presents the results of a field experiment in which we analyze the decisions of subjects taking multiple-choice exams. The evidence suggests that differences between scoring rules are due to risk aversion as theory predicts. We also find that the number of omitted items depends on the scoring rule, knowledge, gender and other covariates.

Grazing by manatees excludes both new and established wild celery transplants: Implications for restoration in Kings Bay, FL, USA

We conducted a field experiment between August 2001 and February 2002 in Kings Bay, FL, USA, designed to determine whether the amount of time allowed for wild celery (Vallisneria americana Michx) transplants to establish altered the effect of herbivorous manatees (Trichechus manatus L.)on their survival.

Influence of Dilute Acetic Acid Treatments on Survival of Monoecious Hydrilla Tubers in the Oregon House Canal, California

Hydrilla (Hydrilla verticillata (L.f.)Royle), a serious aquatic weed, reproduces through formation of underground tubers. To date, attacking this life-cycle stage has been problematic. The purpose of this study was to measure the impact of exposure to dilute acetic acid on monoecious hydrilla tubers under field conditions. In this field experiment, treatments were acetic acid concentration (0, 2.5, or 5%) and sediment condition (perforated or not perforated). Each of 60, 1x1 m plots (in the Oregon House Canal) were randomly assigned to one treatment. Two weeks after treatment, we collected three samples from each plot. One was washed over 2 mm wire mesh screens to separate tubers from sediment. Relative electrolyte leakage was measured for one tuber from each plot. Five additional tubers from each plot were placed in a growth chamber and sprouting monitored for four weeks. A second sample from each plot was placed in a plastic tub and placed in an outdoor tank, filled with water. These samples were monitored for tuber sprouting. Relative electrolyte leakage increased significantly for tubers exposed to 2.5% or 5% acetic acid. Effects on tubers in perforated sediment were reduced. Exposure to acetic acid inhibited tuber sprouting by 80 to 100%, in both chamber and outdoor tests. These results confirm findings from earlier laboratory/greenhouse experiments, and suggest that this approach may be useful in the management of hydrilla tuber banks in habitats where the water level can be lowered to expose the sediments.

Razões, sentimentos e projetos profissionais: experiência dos vestibulandosas (Vitória, ES, 2009 - 2010)

Dar nitidez aos sentimentos e razões que emergem das experiências dos vestibulandos de Vitória-ES, entre 2009-2010, e que os movem em direção a seus projetos profissionais é objetivo deste trabalho. A noção de projeto aqui utilizada (VELHO, 1999) afasta-se da clássica compreensão liberal do ser humano, autônomo, livre e único, responsável por seus sucessos e fracassos, subjacente a estudos sobre escolha profissional. A ideia proposta é que campo de experiências dos sujeitos marca seus projetos profissionais, mas que suas condutas deliberadas, não necessariamente racionais, expõem certas expectativas de vida, quaisquer que sejam as posições sociais desses sujeitos. Para o exame dessas expectativas, esses sujeitos foram vistos em suas relações sociais - nas interseções de classes, gênero, de cor da pele, de gerações, etc. Reconheceu-se, ainda, que razões e sentimentos (WILLIAMS, 1969), também forjam projetos profissionais de sujeitos sob diversas condições sociais e apesar delas. Por considerar que esses projetos portam manifestações humanas, nem sempre perceptíveis e tantas vezes encobertas, a metáfora do rizoma (DELEUZE; GUATTARI, 2004), foi de utilidade metodológica. Alguns indícios (GINZBURG, 2007), sugeriram caminhos de pesquisa e alguns dos significados aos sujeitos para que esses projetos pudessem ser detectados. A perspectiva da longa duração histórica e dos tempos múltiplos presidiu o exame de trajetórias selecionadas de um conjunto de sujeitos pesquisados entre os anos 2009-2010, o que favoreceu a percepção de continuidades históricas, mas também a ocorrência de mudanças de certas tendências sociais. Dois cursos de pré-vestibular, um público e um privado, em Vitória, ES, nessa conjuntura, mostraram um pouco da pluralidade de expectativas de diferentes jovens - pobres, de classes média e alta, homens e mulheres, brancos, negros e pardos, mais novos e mais velhos em relação ao ensino superior presente em seus projetos profissionais. Razões e sentimentos que os movem e que se movem, nem sempre examinados em estudos sobre a matéria, foram expostos. Contribuições de Elias (1990), de R. Williams (1969), de Bourdieu (2003, 2009), de E. P. Thompson (2002), de Löwy (1990), entre outros, apoiaram evidências de que as relações indivíduo e sociedade, sempre plurais e complexas, expressam apenas partes de seus sentidos civilizadores. Para reduzir incertezas, recorreu-se a dados macrossociais e microssociais (REVEL, 1998). Entrevistas com tais jovens e coordenadores de seus cursos, observações advindas de dinâmica de grupo e, também, exame de publicações oficiais, de periódicos de divulgação de matéria sobre vestibular, entre 2009-2010, situaram um trato de escalas analíticas de difícil exercício. Para além das relações de classes, gênero, cor da pele, geração etc., pode-se concluir que esses sujeitos, por razões e sentimentos variados, com seus projetos profissionais, tanto se deslocam de suas posições sociais de origem como as mantêm, mas todos, em suas novas experiências e de diferentes modos, também se preparam para atuar sobre os sentidos civilizadores de seu tempo.

Effects of commercial fishing on local abundance of Pacific cod (Gadus macrocephalus) in the Bering Sea

Groundfish fisheries in the southeast Bering Sea in Alaska have been constrained in recent years by management measures to protect the endangered Steller sea lion (Eumetopias jubatus). There is concern that the present commercial harvest may produce a localized depletion of groundfish that would affect the foraging success of Steller sea lions or other predators. A three-year field experiment was conducted to determine whether an intensive trawl fishery in the southeast Bering Sea created a localized depletion in the abundance of Pacific cod (Gadus macrocephalus). This experiment produced strongly negative results; no difference was found in the rate of seasonal change in Pacific cod abundance between stations within a regulatory no-trawl zone and stations in an immediately adjacent trawled area. Corollary studies showed that Pacific cod in the study area were highly mobile and indicated that the geographic scale of Pacific cod movement was larger than the spatial scale used as the basis for current no-trawl zones. The idea of localized depletion is strongly dependent on assumed spatial and temporal scales and contains an implicit assumption that there is a closed local population. The scale of movement of target organisms is critical in determining regional effects of fishery removals.

El alga invasora Undaria pinnatifida (Harvey) Suringar en la Ría Deseado (Patagonia austral, Argentina): ciclo del esporofito y factores ambientales determinantes de su distribución

Undaria pinnatifida was registered in Ría Deseado (47º45´S, 65º55´W _ southern Patagonia) by the first time in spring 2005, colonizing the intertidal and shallow subtidal. A seasonal survey in 2006 showed that U. pinnatifida was established in a sheltered zone inside the estuary, along a coastal fringe of 8 km between Punta Cascajo and Cañadón del Puerto. This continuous distribution was only interrupted in the mouth of canyons that flow into Ría Deseado, where the bottom is conformed by mud and sand. The sporophytes were mainly found colonizing the rocky bottom in the lower intertidal, bordering the Macrocystis pyrifera population. The highest density and biomass of sporophytes (12.13 ind. m-2; 254.60 g m-2) were registered during spring, when the population was mainly conformed by individuals of medium sizes. The lowest density and biomass (0.33 ind. m-2; 5.69 g m-2) were registered in autumn. Juvenile sporophytes recruited throughout the year, but presented the highest percentage in the population during autumn and winter. First mature sporophytes appeared in spring and attained their maximum size in summer. After this, the sprophytes decayed and disappeared. Environmental factors such as rocky bottoms availability and water transparency may be the main factors determining the sporophytes distribution in Ría Deseado. The field experiment point out that M. pyrifera population is an important factor controlling the dispersion of U. pinnatifida towards the subtidal. SPANISH: Undaria pinnatifida fue registrada en la Ría Deseado (47º45´ S, 65º55´ W _ Patagonia austral) durante la primavera de 2005, colonizando el intermareal y submareal somero. Los relevamientos estacionales realizados durante el 2006, revelaron que U. pinnatifida se encontró establecida en una zona protegida en el interior de la ría, ocupando una franja costera de aproximadamente 8 km de largo entre Punta Cascajo y el Cañadón del Puerto. Esta distribución casi continua sólo presentó algunas interrupciones en la boca de los cañadones que desembocan en la ría, donde el fondo predominante es de tipo areno-fangoso. Los esporofitos de U. pinnatifida ocuparon preferentemente el fondo rocoso del intermareal inferior, limitando con la población de Macrocystis pyrifera. La densidad y biomasa más altas de esporofitos (12,13 ind. m-2; 254,60 g m-2) fueron registradas en primavera, cuando la población se encontró compuesta principalmente por individuos de tallas intermedias. La densidad y biomasa más bajas (0,33 ind. m-2; 5,69 g m-2) fueron registradas durante el otoño. Los esporofitos juveniles se reclutaron a lo largo de todo el año, pero alcanzaron su mayor proporción en la población durante el otoño y el invierno. Los esporofitos reproductivamente maduros aparecieron durante la primavera y alcanzaron su talla máxima durante el verano, luego del cual comenzaron a deteriorarse y a desaparecer. Factores como la disponibilidad de fondos rocosos y la transparencia de las aguas podrían actuar como los principales factores determinantes de su distribución en la ría. El experimento de campo realizado revela que los bosques de M. pyrifera actúan también como un importante factor de control, limitando la dispersión de U. pinnatifida hacia el submareal.

Evaluation of external anchor tags for estimation of growth and survival in tilapia (Oreochromis shiranus chilwae Trewavas)

The effects of tagging with Roy FD-68B T-bar anchor tags on estimates of growth in Tilapia (Oreochromis shiranus chilwae) were investigated in a pond and in a field experiment. In the pond experiment, mean length increments of tagged and marked fish were compared. In the field experiment growth of tagged and "untouched" individual wild fish were compared by measuring scale circuli spacing (Circ.), which is correlated to instantaneous growth rate. Length increments of tagged and untagged/marked fish were not significantly different in either experiment. In the pond experiment, the total mortality rate in the small tagged fish was significantly higher than in the marked fish. The recoveries of tagged fish in the pond experiment increased with fish size. Recoveries exceeded 80% at lengths over 13 cm TL. The ratios of tagged to marked recoveries were 1.02 and 0.74 for large and small fish respectively. The study shows that tagging of Tilapia with Roy anchor tags does not in general alter the growth rates of the fish.

Influence of dew on biomass and photosystem II activity of cyanobacterial crusts in the Hopq Desert, northwest China

Dew is an important water source for desert organisms in semiarid and arid regions. Both field and laboratory experiments were conducted to investigate the possible roles of dew in growth of biomass and photosynthetic activity within cyanobacterial crust. The cyanobacteria, Microcoleus vaginatus Gom. and Scytonema javanicum (Kutz.) Born et Flah., were begun with stock cultures and sequential mass cultivations, and then the field experiment was performed by inoculating the inocula onto shifting sand for forming cyanobacterial crust during late summer and autumn of 2007 in Hopq Desert, northwest China. Measurements of dew amount and Chlorophyll a content were carried out in order to evaluate the changes in crust biomass following dew. Also, we determined the activity of photosystem II(PSII) within the crust in the laboratory by simulating the desiccation/rehydration process due to dew. Results showed that the average daily dew amount as measured by the cloth-plate method (CPM) was 0.154 mm during fifty-three days and that the crust biomass fluctuated from initial inoculation of 4.3 mu g Chlorophyll a cm(-2) sand to 5.8-7.3 mu g Chlorophyll a cm(-2) crust when dew acted as the sole water source, and reached a peak value of approximately 8.2 mu g Chlorophyll a cm(-2) crust owing to rainfalls. It indicated that there was a highly significant correlation between dew amounts and crust moistures (r = 0.897 or r = 0.882, all P < 0.0001), but not a significant correlation between dew and the biomass (r = 0.246 or r = 0.257, all P > 0.05), and thus concluded that dew might only play a relatively limited role in regulating the crust biomass. Correspondingly, we found that rains significantly facilitated biomass increase of the cyanobacterial crust. Results from the simulative experiment upon rehydration showed that approximately 80% of PSII activity could be achieved within about 50 min after rehydration in the dark and at 5 degrees C, and only about 20% of the activity was light-temperature dependent. This might mean that dew was crucial for cyanobacterial crust to rapidly activate photosynthetic activity during desiccation and rehydration despite low temperatures and weak light before dawn. It also showed in this study that the cyanobacterial crusts could receive and retain more dew than sand, which depended on microclimatic characteristics and soil properties of the crusts. It may be necessary for us to fully understanding the influence of dew on regulating the growth and activity of cyanobacterial crust, and to soundly evaluate the crust's potential application in fighting desertification because of the available water due to dew. (C) 2009 Published by Elsevier Ltd.

Manipulation of host density affects infestation of a peritrich ciliate (Epistylis lacustris) on a calanoid copepod (Leptodiaptomus minutus) in Crystal Lake, Wisconsin, USA

Specimens of the calanoid copepod, Leptodiaptomus minutus, collected in June 1994 in oligotrophic: north temperate Crystal Lake, were infested with the stalked ciliate Epistylis lacustris. E. lacustris was highly specific to L. minutus and no other coexisting zooplankters were infested. Excluding nauplii, nearly 70% of copepods carried 1-20 ciliates, although the maximum load was as high as 250 ciliates. A lower percentage of nauplii were infested by the ciliate; those that were infested had a lower ciliate load than other copepod stages. Infestation by ciliates had no significant influence on the average egg number of female copepods. In a field experiment, higher copepod densities in enclosures resulted in a significantly higher infestation rate, but the ciliate load per individual copepod did not differ significantly among treatments.

Ground target detection, classification and sensor fusion in distributed fiber seismic sensor network - art. no. 683015

This paper describes the ground target detection, classification and sensor fusion problems in distributed fiber seismic sensor network. Compared with conventional piezoelectric seismic sensor used in UGS, fiber optic sensor has advantages of high sensitivity and resistance to electromagnetic disturbance. We have developed a fiber seismic sensor network for target detection and classification. However, ground target recognition based on seismic sensor is a very challenging problem because of the non-stationary characteristic of seismic signal and complicated real life application environment. To solve these difficulties, we study robust feature extraction and classification algorithms adapted to fiber sensor network. An united multi-feature (UMF) method is used. An adaptive threshold detection algorithm is proposed to minimize the false alarm rate. Three kinds of targets comprise personnel, wheeled vehicle and tracked vehicle are concerned in the system. The classification simulation result shows that the SVM classifier outperforms the GMM and BPNN. The sensor fusion method based on D-S evidence theory is discussed to fully utilize information of fiber sensor array and improve overall performance of the system. A field experiment is organized to test the performance of fiber sensor network and gather real signal of targets for classification testing.

Surface plasmon waves generated by nanogrooves through spectral interference

A pure surface plasmon polariton (SPP) model predicted that the SPP excitation in a slit-groove structure at metallodielectric interfaces exhibits an intricate dependence on the groove width P. Lalanne et al. [Phys. Rev. Lett. 95, 263902 (2005); Nat. Phys. 2, 551 (2006)]. In this paper, we present a simple far-field experiment to test and validate this interesting theoretical prediction. The measurement results clearly demonstrate the predicted functional dependence of the SPP coupling efficiency on groove width, in good agreement with the SPP picture.

施肥措施对黄土旱塬区小麦产量和土壤有机碳积累的影响

利用中国科学院长武农田生态试验站的长期田间试验(1984年2~007年),研究了小麦产量,耕层有机碳变化,评价了土壤管理和气候因素对土壤有机碳(Soil organic C,SOC)变化的影响。研究涉及6个处理:休闲地(F);不施肥(CK);有机肥(M);氮肥(N);氮、磷肥(NP)和氮、磷、有机肥(NPM)处理。结果表明,施肥可以显著提高作物产量和SOC积累,CK、M、N、NP、NPM处理平均产量依次为1.5、2.6、2.0、3.3、4.0 t/hm2,2007年F、CK、M、N、NP、NPM处理0—20 cm土层SOC积累量依次为-1.09、0.76、8.59、1.02、3.42和9.5 t/hm2。作物产量与SOC含量呈显著的正相关关系(r=0.80),有机碳输入量与SOC含量相关性更好(r=0.97),外源有机碳的输入也是提高SOC的重要措施。施肥措施对作物固碳和SOC影响存在显著(P<0.05)差异。土壤固碳速率(Y)与SOC输入量(X)符合线性方程Y=0.231X-0.0813(r=0.98)。施肥可以提高黄土高原半干旱地区土壤生产力和SOC的积累,且无机肥和有机肥配施效果最佳。

田间含碎石土壤水分入渗及再分布试验研究

为探明碎石存在于田间土壤中如何改变土壤水分运移通道、影响土壤水分运动,揭示田间含碎石土壤水分运动的复杂过程,采用便携式针头降雨器在铜川崾岘梁修建的临时小区进行模拟降雨实验,测定含碎石浅层土体的入渗和水分再分布过程,采用土壤水分运动通量法计算浅层土体不同深度各截面面积的水量在雨后不同时间段的变化,分析含碎石土壤再分布特征及碎石含量对浅层土体入渗和水分再分布的影响。结果表明:碎石有利于田间浅层土壤入渗和蓄存;室内较田间测定的含碎石土壤入渗率小一个数量级以上;降雨后较短时段,碎石含量相对高的林地小区的浅层土体水分在降雨停止后呈增加趋势,表现了蓄水过程,碎石含量较低的撂荒地则表现了释水过程;降雨后较长时段,多数小区浅层土体(0-30 cm)水量变化呈现了"排水-存储交换-排水"过程,少数小区仅呈现了"排水"过程;雨后16 h左右的土体各截面面积的水量与碎石含量呈现了以直线y=0.4873为轴对称的递增和递减的指数为1/2的幂函数关系,说明碎石对黄土区典型土石区土体水分运动具有促进和阻滞双面影响。本文的研究结果可为含碎石土壤的水分利用及水分循环提供参考。