O presente trabalho pretende contribuir para o conhecimento do sistema construtivo “Log-house” através de uma vasta análise experimental e de análises numéricas. A campanha experimental, realizada previamente, teve por objectivo de estudar o comportamento no plano das paredes em troncos de madeira quando sujeitas a acções monotónicas e cíclicas, de acordo com a EN 12512:2001. Apresenta-se ainda um caso de estudo, relativo a uma moradia produzida e comercializada pela empresa “Rusticasa”, no qual se considera a distribuição das forças sísmicas em função: a) da área de influência de cada parede e, b) da rigidez de cada parede. As análises efectuadas contemplam algumas verificações de resistência, nomeadamente ao nível da ligação à fundação e no cruzamento entre paredes ortogonais, as quais não são verificadas na totalidade pelo que se apresentam algumas sugestões a implementar no sistema construtivo com vista à verificação da segurança.; This paper aims to contribute to the knowledge of the building system "Log-house” through an extensive experimental analysis and numerical analysis. The experimental campaign, performed previously, aimed of studying the in-plane behavior of log walls when subjected to monotonic and cyclic loads...
The present works intends to represent a further step in the knowledge of timber log-houses through an
experimental approach, from which only few information is available. The main part of the experimental work is based
on in-plane static tests conducted on timber log walls with distinct transversal stiffness, two vertical compression levels
and two values of slenderness. Monotonic and cyclic tests were performed according to EN 12512:2001. The formers
were performed to define the elastic slip values and assessment of the failure mechanisms while the lasts allowed
evaluating impairment of strength, to measure the ductility and to quantify the energy dissipation. In a first step
research, an extensive characterization of the timber logs was made. The connection between the first timber log and the
basement was also evaluated.
Dissertação de mestrado (ciclo de estudos integrado em Engenharia Civil); A madeira, enquanto material de construção, já ocupou no passado um lugar de
destaque. Contudo, o aparecimento de outros materiais, como o aço e o betão, levou quase
ao seu abandono total para fins estruturais. Excepção a esta tendência viveu-se nos países
do Norte e Centro da Europa, sendo exemplo o sistema construtivo “Log-house”. Este
sistema construtivo consiste na construção de paredes através da sobreposição de troncos
de secção circular ou rectangular, geralmente possuindo nas faces superior e inferior um
entalhe de forma a aumentar a superfície de contacto e a estabilidade.
As paredes que constituem este sistema construtivo conferem-lhe resistência
estrutural e estabilidade face às acções verticais e horizontais, quer no seu plano, quer no
plano perpendicular. A resistência às acções verticais depende da área de contacto entre os
toros e da resistência à compressão perpendicular às fibras da madeira, enquanto as
acções horizontais perpendiculares ao plano da parede serão suportadas pelas paredes
transversais, dependendo a estabilidade das paredes a acções horizontais no seu plano do
atrito desenvolvido nos entalhes que cada toro possui e da resistência oferecida pelas
Face à falta de conhecimento do comportamento destas construções em caso de
ocorrência de um sismo...
The current paper deals with the analysis of the results yielded by a series of tests performed to evaluate the seismic behaviour of a model log construction. The study was based on an experimental investigation performed to improve the existing knowledge on log houses subject to seismic events. The main part of the experimental work is based on a full scale shaking table test, conducted on a two-storey log house designed by the Portuguese company Rusticasa® in compliance with design rules for timber buildings. The test was performed by the University of Minho within the framework of the SERIES Project ‘Multi-storey timber buildings’ and was coordinated by the University of Trento, at LNEC, Lisbon, Portugal.
The geometry of the specimen, the design of the test, the setup and the instrumentation layout are first presented in this paper. The test procedure was conducted in stages with maximum accelerations (bi-directional) of 0.07g, 0.28g and 0.5g. The experimental results of each test have been analyzed and the resultant values of inter-storey drift, wall slippage and uplift measurements, shear deformations and hold-down forces measured are presented. Most importantly, the dynamic properties (fundamental period and mode shapes) of the system have been determined.
Fonte: Taylor & Francis GroupPublicador: Taylor & Francis Group
Tipo: Conferência ou Objeto de Conferência
Publicado em //2013ENG
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The current work presents a full scale shaking table test conducted on a twostoreyed
timber log house, designed according to the state of the art on timber engineering. The
test was performed within the framework of the SERIES Project “Multi-storey timber buildings”
at LNEC, Lisbon, Portugal. Several tests and studies have been carried out by the University
of Minho to characterize the behavior of the different components (logs, walls, slabs, connections,
etc.) of log houses in the past few years for the European Technical Approval (ETA)
of this construction system. The main results of the shaking table test are presented along with
the preliminary analysis of the overall behavior of the log house. The analysis was carried out
based on the shaking table tests and on a numerical model developed to estimate the main seismic
parameters using the data obtained from the different individual studies on each component
of the construction system performed within the framework of the ETA.
An in-house reverse transcription (RT)-competitive PCR (RT-cPCR) for the quantitation of human immunodeficiency virus type 1 (HIV-1) RNA in plasma samples was developed and validated. The procedure involves (i) extraction of RNA with spin columns, (ii) ready-to-use bead-mediated RT, (iii) competitive PCR in a microtiter plate, (iv) agarose gel electrophoresis of the reaction products, and (v) densitometric analysis of the digitized image of the gel. Quadruplicate tests and dilution studies showed that the sensitivity and intertest coefficient of variability of the RT-cPCR are comparable to those of the reference AMPLICOR HIV-1 MONITOR test. The results obtained by the two assays with a panel of 45 clinical samples were in good agreement (mean difference, 0.36 ± 0.25 log units). Analysis of 1,982 clinical samples by the in-house RT-cPCR yielded the typical range of plasma HIV-1 RNA levels with the expected inverse correlation between CD4 counts and HIV-1 RNA titers. In addition, testing of plasma from 36 subjects at weeks 0 and 4 with respect to the time of initiation of protease inhibitor therapy detected a significant decrease in HIV-1 viremia. The mean reduction in the HIV-1 RNA level was 0.914 log unit for those receiving saquinavir (P = 0.0210)...
OBJECTIVE: To determine whether use of a log book improved the experiences of preregistration house officers. DESIGN: Confidential questionnaire and interview survey of preregistration house officers carried out as part of University of London inspection process. MEASURES: Preregistration house officers were asked to rate educational and pastoral elements of their posts and about the use made of previously distributed log books. SUBJECTS AND SETTING: Preregistration house officers in North Thames. RESULTS: The incumbents of 535 of 560 (95%) preregistration house officer posts in the region were surveyed between June 1994 and July 1995, 490 by questionnaire and interview, 45 by questionnaire alone. House officers who had discussed the log book with their consultant expressed more satisfaction with their induction, consultant supervision and feedback, and formal and informal education and were more likely to recommend their job to a friend. CONCLUSION: Preregistration house officers who had discussed the log book with their consultant expressed more satisfaction with the educational elements of their jobs. The structured discussion with their consultant about the job and their performance seemed to make the difference.
Restrictions on the use of polybrominated diphenyl ethers (PBDEs) have resulted in the increased use of alternate flame retardant chemicals to meet flammability standards. However, it has been difficult to determine which chemical formulations are currently being used in high volumes to meet flammability standards since the use of flame retardant formulations in consumer products is not transparent (i.e. not provided to customers). To investigate chemicals being used as replacements for PentaBDE in polyurethane foam, we analyzed foam samples from 26 different pieces of furniture purchased in the United States primarily between 2003 and 2009 using gas chromatography mass spectrometry. Samples included foam from couches, chairs, mattress pads, pillows, and, in one case, foam from a sound proofing system of a laboratory grade dust sieve. Fifteen of the foam samples contained the flame retardant tris(1,3-dichloro-2-propyl) phosphate (TDCPP; 1–5% by weight), four samples contained tris(1-chloro-2-propyl) phosphate (TCPP; 0.5 –2.2 % by weight), one sample contained brominated chemicals found in a new flame retardant mixture called Firemaster 550 (4.2% by weight), and one foam sample collected from a futon likely purchased prior to 2004 contained PentaBDE (0.5% by weight). Due to the high frequency of detection of the chlorinated phosphate compounds in furniture foam...
The majority of particles that adhere to hands are <63 μm in diameter yet risk assessments for soil remediation are typically based on soil samples sieved to <250 μm. The objective of our study was to determine if there is a significant difference in metal concentration by particle size in both house dust and soil. We obtained indoor dust and yard soil samples from 10 houses in Tucson, Arizona. All samples were sieved to <63 μm and 63 to <150 μm and analyzed for 30 elements via ICP-MS following nitric acid digestion. We conducted t-tests of the log-transformed data to assess for significant differences that were adjusted with a Bonferroni correction to account for multiple comparisons. In house dust significant differences in concentration were observed for Be, Al, and Mo between particles sizes, with a higher concentration observed in the smaller particles size. Significant differences were also determined for Mg, Ca, Cr, Co, Cu, Ge, Zr, Ag, Ba, and Pb concentration in yard soil samples, with the higher concentration observed in the smaller particles size for each element. The results of this exploratory study indicate that current risk assessment practices for soil remediation may under estimate non-dietary ingestion exposure. This is of particular concern for young children who are more vulnerable to this exposure route due to their high hand mouthing frequencies. Additional studies with a greater number of samples and wider geographic distribution with different climates and soil types should be completed to determine the most relevant sampling practices for risk assessment.
The optimal conditions for mycelial growth of Phellinus linteus ATCC 26710 were determined to be a log length of 20 cm, temperature of 30℃ and pH of 6.0. Mycelial growth was excellent on the mushroom complete medium, and was optimal when sucrose, mannose and glucose were supplied as carbon sources. Potassium nitrate and sodium nitrate as nitrogen sources supported good mycelial growth. To evaluate P. linteus mycelial colonization on logs, sterilized short log inoculation, drilling inoculation and log-end sandwich inoculation techniques were used. Only sterilized short log inoculation produced good mycelial colonization. Initial mycelial growth and full mycelial colonization were best on 20 cm logs having 42% moisture content. The initial mycelial growth of P. linteus was accelerated over 12 hr of sterilization. Basidiocarp formation was optimal using a burying method of logs after 5~6 months, and fruiting body formation was superior in cultivation house conditions of 31~35℃ and in excess of 96% relative humidity.
(Biographical) Martha House Allen (1827-1900) and her husband Charles J. Allen (1822-1887) were from Baring St., Philadelphia.; Originally derived from archival-level ALEPH record 028140097 ( OCLC: 49280356 ); (Funding) Funded by the National Historical Publications and Records Commission (NHPRC) as part of the Pioneer Days in Florida Project
(Biographical) Martha House Allen (1827-1900) and her husband Charles J. Allen (1822-1887) were from Baring St., Philadelphia.; Originally derived from archival-level ALEPH record 028140097 ( OCLC: 49280356 ); (Funding) Funded by the National Historical Publications and Records Commission (NHPRC) as part of the Pioneer Days in Florida Project; Metadata, abstract, transcription, and scanning by Caitlin Logroño.
Battlefield House was originally the home of Mary Gage, a widow who arrived in Canada with 2 children after her husband was killed in action in the American Revolution in 1777. The original house was a log cabin which was replaced by a storey and a half frame house.
Col. Nelson was the next owner of the house, and in the middle of the 19th century he raised the roof to make it a 2 storey house and added a large west wing. Successive owners: the Glover, Williams and Fisher families made a few changes to the house. The last owner was D.A. Fletcher who tore down the newer, western half of the building in 1895.
In 1899, Mrs. John Calder, a granddaughter of James Gage formed the Women’s Wentworth Historical Society and raised enough money to buy the Gage Farmhouse and the land around it on which the Battle of Stoney Creek was fought. In 1910 this group purchased another 13 acres of the original Crown Grant and made 17 ½ acres of parkland open to the public. The women of the Society renovated and furnished the house. They maintained the building for 63 years. It was due to them that a monument was erected above the house by the Dominion Government. The monument was unveiled on the 100th anniversary of the Battle, June 6, 1913.
The house was turned over by the Historical Society to The Niagara Parks Commission on January 19th...
We introduce the study of the ant colony house-hunting problem from a
distributed computing perspective. When an ant colony's nest becomes unsuitable
due to size constraints or damage, the colony must relocate to a new nest. The
task of identifying and evaluating the quality of potential new nests is
distributed among all ants. The ants must additionally reach consensus on a
final nest choice and the full colony must be transported to this single new
nest. Our goal is to use tools and techniques from distributed computing theory
in order to gain insight into the house-hunting process.
We develop a formal model for the house-hunting problem inspired by the
behavior of the Temnothorax genus of ants. We then show a \Omega(log n) lower
bound on the time for all n ants to agree on one of k candidate nests. We also
present two algorithms that solve the house-hunting problem in our model. The
first algorithm solves the problem in optimal O(log n) time but exhibits some
features not characteristic of natural ant behavior. The second algorithm runs
in O(k log n) time and uses an extremely simple and natural rule for each ant
to decide on the new nest.; Comment: To appear in PODC 2015
Accumulating evidence is suggesting that exposure to some environmental contaminants may alter adipogenesis, resulting in accumulation of adipocytes, and often significant weight gain. Thus these types of contaminants are often referred to as obesogens. Many of these contaminants act via the activation (i.e. agonism) of the peroxisome proliferator activated receptor γ (PPARγ) nuclear receptor. To date, very few chemicals have been identified as possible PPAR ligands. In the thesis, our goal was to determine the PPARγ ligand binding potency and activation of several groups of major semi-volatile organic compounds (SVOCs) that are ubiquitously detected in indoor environments, including flame retardants such as polybrominated diphenyl ethers (PBDEs) and Firemaster 550 (FM550), and other SVOCs such as phthalates, organotins, halogenated phenols and bisphenols. Additional attention was also given to the potential activity of the major metabolites of several of these compounds. Since the primary sink for many of these SVOCs is dust, and dust ingestion has been confirmed as an important pathway for SVOCs accumulation in humans, the potential PPAR binding and activation in extracts from environmentally relevant dust samples was also investigated.
Previous studies have also shown that SVOCs sorbed to organic matrices (e.g....
Between September 1998 and June 1999, CHAD students and staff documented
eight properties located throughout the state, including a kitchen/slave quarter, a
nineteenth century urban commercial block, several farm dwellings, a Methodist church,
and a log stable. Sites were documented in all three counties in Delaware, in both urban
and rural settings.
Constructed ca. 1855, the Joseph Crawford House is an unusual survivor as a log dwelling that retains a high degree of its architectural integrity. The Period I section is entirely intact and features a hall-chamber plan with the interior walls completely exposed on both the first and second floors.