913 resultados para Roof top PV


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Banana bunchy top virus (BBTV) was readily transmitted through tissue culture in banana (Mum sp.) cv. Lady finger (AAB) and Cavendish cv. Williams (AAA). Lines derived from infected and healthy field plants had similar in vitro multiplication rates. BBTV infected in vitro cultures displayed symptoms of stunting, leaf curling, chlorotic and green flecks, and poor root growth. Symptoms became milder with time, and were often difficult to discern in older, rapidly multiplying cultures. A triple antibody sandwich ELISA using polyclonal and monoclonal antibodies was very efficient for detecting BBTV in vitro. Symptomless, ELISA-negative plants arose in 10 out of 11 lines derived from BBTV-infected field plants and first appeared after 9 months continuous in vitro culture at a constant 28OC. Meristem tip culture or heat therapy was not used. These plants remained symptomless and ELISA-negative after planting out in the glasshouse (individual plants checked for up to 16 months). The implications of this inconsistent transmission of BBTV for germplasm indexing and exchange are discussed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Throughout the 19th century, the top hat was a mainstay of Victorian life: a man in a topper was well-to-do, respectable, a man of industry. But now the top hat is only a caricature of the upper class privilege it once represented. Its history traces a line through dandies, beavers, silk, and madness...

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This study investigated the cool roof technology effects on annual energy saving of a large one-storey commercial building in Queensland, Australia. A computer model of the case study was developed using commercial software by using the appropriate geometrical and thermal building specifications. Field study data were used to validate the model. The model was then used to extend the investigation to other cities in various Australian climate zones. The results of this research show that significant energy savings can be obtained using cool roof technology, particularly in warm, sunny climates, and the thesis can contribute to provide a guideline for application of cool roof technology to single-storey commercial building throughout Australia.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Two isolates of a novel babuvirus causing "bunchy top" symptoms were characterised, one from abaca (Musa textilis) from the Philippines and one from banana (Musa sp.) from Sarawak (Malaysia). The name abacá bunchy top virus (ABTV) is proposed. Both isolates have a genome of six circular DNA components, each ca. 1.0-1.1 kb, analogous to those of isolates of Banana bunchy top virus (BBTV). However, unlike BBTV, both ABTV isolates lack an internal ORF in DNA-R, and the ORF in DNA-U3 found in some BBTV isolates is also absent. In all phylogenetic analyses of nanovirid isolates, ABTV and BBTV fall in the same clade, but on separate branches. However, ABTV and BBTV isolates shared only 79-81% amino acid sequence identity for the putative coat protein and 54-76% overall nucleotide sequence identity across all components. Stem-loop and major common regions were present in ABTV, but there was less than 60% identity with the major common region of BBTV. ABTV and BBTV were also shown to be serologically distinct, with only two out of ten BBTV-specific monoclonal antibodies reacting with ABTV. The two ABTV isolates may represent distinct strains of the species as they are less closely related to each other than are isolates of the two geographic subgroups (Asian and South Pacific) of BBTV.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Most musicians choose a career in music based on their love of the art and a desire to share it with others. However, being a performing musician is highly demanding. Despite considerable evidence of the great frequency of performance-related problems (e.g. debilitating performance anxiety) among professional musicians or aspiring musicians in the current Western classical music tradition these problems are seldom discussed openly. The existing system offers musicians very little help in learning how to build sustainable performance success into their musical career. This study it is first of its kind in Finland which addresses the issue on larger scale in a systematic way. I devised the HOPE intervention (Holistically-Oriented Top Performance and Well-Being Enhancement), in order to learn how to integrate professional peak performance and a sense of personal well-being into the lives and careers of musicians. Unlike most interventions in previous research, the HOPE intervention is explicitly holistic and aims at enhancing the whole musician, not just alleviating performance anxiety. Earlier research has not in principle focused on musicians´ psychological well-being or on their subjective perceptions. The main purpose of the study is to understand the perceived impacts of the specially devised HOPE intervention on the participants and particularly in four key areas: performing, playing or singing well-being, and overall (performing, playing or singing and well-being combined). Furthermore, it is hoped that a deeper understanding of performers´ development will be gained. The research method is interdisciplinary and mainly qualitative. The primary data consist of a series of linked questionnaires (before and after the intervention) and semi-structured follow-up interviews collected during action research-oriented HOPE intervention courses for music majors in the Sibelius Academy. With the longitudinal group called Hope 1, the core data were collected during a nine month HOPE intervention course and from follow-up interviews conducted six months later in 2003-2004. The core data of Hope 1 (nine participants) are compared with the perceived impacts on fifty-three other participants in the HOPE courses during the period since their inception, 2001-2006. The focus is particularly on participants´ subjective perceptions. Results of the study suggest that the HOPE intervention is beneficial in enhancing overall performance capacity, including music performance, and a personal sense of well-being in a music university setting. The findings indicate that within all key areas significant positive changes take place between the beginning and the end of a HOPE intervention course. The longitudinal data imply that the perceived positive changes are still ongoing six months after the HOPE intervention course is finished. The biggest change takes place within the area of performing and the smallest, in participants´ perception of their playing or singing. The main impacts include reduced feelings of stress and anxiety (an enhanced sense of well-being) as well as increased sense of direction and control in one's life. Since the results of the present research gave no other reason to believe otherwise, it is to be expected that the HOPE intervention and the results of the study can be exploited in other areas of human activity as well, especially where continuous professional top performance is a prerequisite such as in business or sports. Keywords: performance enhancement, professional top performance, subjective well-being, subjective perceptions, holism, coaching, music performance anxiety, studying music, music.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Steel roofs made of thin cold-formed steel roof claddings and battens are widely used in low-rise residential and industrial buildings all around the world. However, they suffer from premature localised pull-through failures in the batten to rafter connections during high wind events. A recent study proposed a suitable design equation for the pull-through failures of thin steel roof battens. However, it was limited to static wind uplift loading. In contrast, most cyclone/storm events produce cyclic wind uplift forces on roofs for a significantly long period, thus causing premature fatigue pull-through failures at lower loads. Therefore, a series of constant amplitude cyclic load tests was conducted on small and full scale roof panels made of a commonly used industrial roof batten to develop their S-N curves. A series of multi-level cyclic tests, including the recently introduced low-high-low (LHL) fatigue loading test, was also undertaken to simulate a design cyclone. Using the S-N curves, the static pull-through design capacity equation was modified to include the effects of fatigue. Applicability of Miner’s rule was evaluated in order to predict the fatigue damage caused by multi-level cyclic tests such as the LHL test, and suitable modifications were made. The combined use of the modified Miner’s law and the S-N curve of roof battens will allow a conservative estimation of the fatigue design capacity of roof battens without conducting the LHL tests simulating a design cyclone. This paper presents the details of this study, and the results.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Large integration of solar Photo Voltaic (PV) in distribution network has resulted in over-voltage problems. Several control techniques are developed to address over-voltage problem using Deterministic Load Flow (DLF). However, intermittent characteristics of PV generation require Probabilistic Load Flow (PLF) to introduce variability in analysis that is ignored in DLF. The traditional PLF techniques are not suitable for distribution systems and suffer from several drawbacks such as computational burden (Monte Carlo, Conventional convolution), sensitive accuracy with the complexity of system (point estimation method), requirement of necessary linearization (multi-linear simulation) and convergence problem (Gram–Charlier expansion, Cornish Fisher expansion). In this research, Latin Hypercube Sampling with Cholesky Decomposition (LHS-CD) is used to quantify the over-voltage issues with and without the voltage control algorithm in the distribution network with active generation. LHS technique is verified with a test network and real system from an Australian distribution network service provider. Accuracy and computational burden of simulated results are also compared with Monte Carlo simulations.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Born July 15, 1914, died August 6, 1978

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Database schemes can be viewed as hypergraphs with individual relation schemes corresponding to the edges of a hypergraph. Under this setting, a new class of "acyclic" database schemes was recently introduced and was shown to have a claim to a number of desirable properties. However, unlike the case of ordinary undirected graphs, there are several unequivalent notions of acyclicity of hypergraphs. Of special interest among these are agr-, beta-, and gamma-, degrees of acyclicity, each characterizing an equivalence class of desirable properties for database schemes, represented as hypergraphs. In this paper, two complementary approaches to designing beta-acyclic database schemes have been presented. For the first part, a new notion called "independent cycle" is introduced. Based on this, a criterion for beta-acyclicity is developed and is shown equivalent to the existing definitions of beta-acyclicity. From this and the concept of the dual of a hypergraph, an efficient algorithm for testing beta-acyclicity is developed. As for the second part, a procedure is evolved for top-down generation of beta-acyclic schemes and its correctness is established. Finally, extensions and applications of ideas are described.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Including Hilde Caro, Lotte Lipschitz and Ellen Milch

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Photovoltaic (PV) panels and electric domestic water heater with storage (DWH) are widely used in households in many countries. However, DWH should be explored as an energy storage mechanism before batteries when households have excess PV energy. Through a residential case study in Queensland, Australia, this paper presents a new optimized design and control solution to reduce water heating costs by utilizing existing DWH energy storage capacity and increasing PV self-consumption for water heating. The solution is produced by evaluating the case study energy profile and numerically maximizing the use of PV for DWH. A conditional probability matrix for different solar insolation and hot water usage days is developed to test the solution. Compared to other tariffs, this solution shows cost reduction from 20.8% to 63.3% This new solution could encourage solar households move to a more economical and carbon neutral water heating method.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We show simultaneous p- and n-type carrier injection in a bilayer graphene channel by varying the longitudinal bias across the channel and the top-gate voltage. The top gate is applied electrochemically using solid polymer electrolyte and the gate capacitance is measured to be 1.5 microF cm(-2), a value about 125 times higher than the conventional SiO(2) back-gate capacitance. Unlike the single-layer graphene, the drain-source current does not saturate on varying the drain-source bias voltage. The energy gap opened between the valence and conduction bands using top- and back-gate geometry is estimated.