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1.
In this paper the structural system reliability method is applied to a built SWATH ship. Firstly, a typical transverse frame in the SWATH is idealized by a one-dimensional model through a series of finite element analyses. The safety margins are automatically generated by computer and the interaction of bending moment and axial force, including buckling effect, is taken into account. The significant failure modes of the structure are identified by an extended β-unzipping method, and the system reliability index is then evaluated by Ditlevsen's bounds. It is found that the most critical section is in the haunch area, and all the critical sections included in the significant failure paths are in the haunch area. 相似文献
2.
Review 总被引:1,自引:0,他引:1
Jacquelin Burgess Peter Faulkner Peter Quartermaine Brian D. Giles Paul Rodaway Tom Turner 《Landscape Research》1991,16(1):30-48
Richard Mabey, Home Country London: Century 1990 £14.95
A Tour of the Lakes in Cumberland. John Ruskin's Diary for 1830. James S. Dearden, (Ed.), with an Introduction by Van Akin Burd. Scolar Press, Aldershot, 1990.
The Landscape Vision of Paul Nash, Roger Cardinal. Reaktion Books, London, 1989. £9,95 paperback ISBN 0948462 02 7
M G R Cannell & M D Hooper, The Greenhouse Effect and Terrestrial Ecosystems of the UK London, HMSO, 1990. 56pp. £4.95
Amenity In Action, The Civic Trust Handbook of Community Initiatives compiled & edited by Deirdre Genet, Societies Development Officer, The Civic Trust (1989), (supported by the Shell Better Britain Campaign)
Sue Minter The Greatest Glass House: The rainforests recreated HMSO, 1990. £25.00 相似文献
A Tour of the Lakes in Cumberland. John Ruskin's Diary for 1830. James S. Dearden, (Ed.), with an Introduction by Van Akin Burd. Scolar Press, Aldershot, 1990.
The Landscape Vision of Paul Nash, Roger Cardinal. Reaktion Books, London, 1989. £9,95 paperback ISBN 0948462 02 7
M G R Cannell & M D Hooper, The Greenhouse Effect and Terrestrial Ecosystems of the UK London, HMSO, 1990. 56pp. £4.95
Amenity In Action, The Civic Trust Handbook of Community Initiatives compiled & edited by Deirdre Genet, Societies Development Officer, The Civic Trust (1989), (supported by the Shell Better Britain Campaign)
Sue Minter The Greatest Glass House: The rainforests recreated HMSO, 1990. £25.00 相似文献
3.
In laboratory experiments, we investigated two task/ambient conditioning systems with air supplied from desk-mounted air outlets to efficiently ventilate the breathing zone of heated manikins seated at desks. In most experiments, the task conditioning systems provided outside air while a conventional ventilation system provided additional space cooling but no outside air. Air change effectiveness (i.e., exhaust air age divided by age of air at the manikin's face) was measured with a tracer gas step-up procedure. Other tracer gases simulated the release of pollutants from nearby occupants and from the floor covering, and the associated pollutant removal efficiencies (i.e., exhaust air concentrations divided by concentrations at manikin's face) were calculated. High values of air change effectiveness (approximately 1.3 to 1.9) and high values of pollutant removal efficiency (approximately 1.2 to 1.6) were measured when these task conditioning systems supplied 100% outdoor air at a flow rate of 7 to 9 L s-1 per occupant. Air change effectiveness was reasonably well correlated with the pollutant removal efficiency. Overall, the experimental data suggest that these task/ambient conditioning systems can be used to improve ventilation and air quality or to save energy while maintaining a typical level of IAQ at the breathing zone. 相似文献
4.
Nader Tehrani Dan Gallagher Katie Faulkner Tim Wong Craig Chapple John Houser Ellee Lee Kevin Lee Parke MacDowell Ryan Murphy Jonathan Palazzolo Caitlin Scott Joana Rafael Rawan Alsane 《世界建筑导报》2018,(2)
正几个世纪以来,不同的地理环境一直都采用这类封闭的庭院形式——每一次都根据当地气候、风俗习惯和建筑实践进行改造。作为一种在建筑物内捕捉户外景观的手段,庭院由建筑内部结构决定。流畅的庭院不但提供内外部隐私保护,而且也不断地向外延伸,积极融入周边景观。该住宅遵守严格的分区指导方针,同时通过在屋顶上扩建自然植物区系与景观融合。坐落在橄榄树林、松树和葡萄园内,该住宅充分利用坡地,从而获得可持续的拓展和种植 相似文献
5.
The objective of the present study was to characterize the performance of a federal reference method (FRM) PM10 size-selective inlet using analysis methods designed to minimize uncertainty in measured sampling efficiencies for large particles such as those most often emitted from agricultural operations. The performance of an FRM PM10 inlet was characterized in a wind tunnel at a wind speed of 8 km/h. Data were also collected for 20 and 25 μm particles at wind speeds of 2 and 24 km/h. Results of the present sampler evaluation compared well with those of previous studies for a similar inlet near the cutpoint, and the sampler passed the criteria required for certification as a FRM sampler when tested at 8 km/h. Sampling effectiveness values for particles with nominal diameters of 20 and 25 μm exceeded 3% for 8 and 24 km/h wind speeds in the present study and were statistically higher than both the “ideal” PM10 sampler (as defined in 40 CFR 53) and the ISO (1995) standard definition of thoracic particles (p < 0.05) for 25 μm particles leading to the potential for significant sampling bias relative to the “ideal” PM10 sampler when measuring large aerosols.
Copyright 2014 American Association for Aerosol Research 相似文献
6.
7.
Jingjing Liu Yimin Zhou Grahame E. Faulkner Dominic C. O'Brien Steve Collins 《International Journal of Circuit Theory and Applications》2015,43(7):840-853
The ability to create and direct beams of light means that optical communications potentially offer a large power advantage over RF communications for sensor networks. This paper presents an optically powered receiver front end for wireless optical communications. A complete optical receiver front end including a photodetector, clock and Manchester data recovery circuits has been fabricated using the UMC 180 nm CMOS process. A novel modulation scheme is described that has been devised so that this front end can recover the clock and Manchester data from an optical beam. Experimental results show that the total current consumption of the optical receiver front end is as low as 18.8 nA for a 0.5 V supply when a 1 kbps Manchester data and 8 kHz clock signal are successfully recovered. This means that photodiodes on the same substrate as the front end circuits extract enough power from the communications beam to allow the front end to work at distances of up to 10 m from the transmitter. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
8.
9.
Peter N. Ciesielski Christopher J. Faulkner Matthew T. Irwin Justin M. Gregory Norman H. Tolk David E. Cliffel G. Kane Jennings 《Advanced functional materials》2010,20(23):4048-4054
The long‐term success of photosynthetic organisms has resulted in their global superabundance, which is sustained by their widespread, continual mass‐production of the integral proteins that photocatalyze the chemical processes of natural photosynthesis. Here, a fast, general method to assemble multilayer films composed of one such photocatalytic protein complex, Photosystem I (PSI), onto a variety of substrates is reported. The resulting films, akin to the stacked thylakoid structures of leaves, consist of a protein matrix that is permeable to electrochemical mediators and contain a high concentration of photoelectrochemically active redox centers. These multilayer assemblies vastly outperform previously reported monolayer films of PSI in terms of photocurrent production when incorporated into an electrochemical system, and it is shown that these photocatalytic properties increase with the film thickness. These results demonstrate how the assembly of micron‐thick coatings of PSI on non‐biological substrates yields a biohybrid ensemble that manifests the photocatalytic activity of the film’s individual protein constituents, and represent significant progress toward affordable, biologically‐inspired renewable energy conversion platforms. 相似文献
10.
LM Bavisotto NH Patel SJ Althaus DM Coldwell HV Nghiem T Thompson B Storer CR Thomas 《Canadian Metallurgical Quarterly》1999,5(1):95-109
We assessed a regimen of alternating regional and systemic therapy in patients with gastrointestinal malignancies with liver-dominant metastases for feasibility, toxicity, response rate, response duration, patterns of progression, and progression-free and overall survival. Regional therapy comprised selective hepatic transcatheter arterial chemoembolization (TACE) using a suspension of cisplatin and particulate polyvinyl alcohol. This procedure was delivered between cycles of protracted continuous infusion 5-fluorouracil (PCI-5FU) as systemic chemotherapy. Patient eligibility criteria included: (a) having histologically documented adenocarcinoma arising from a gastrointestinal primary site with unresectable liver metastases bidimensionally measurable on computerized tomography scan; (b) age greater than 18 years; and (c) performance status 0-2 (Zubrod). PCI-5FU (250 mg/m2/day) was administered i.v. for 28 days, followed by the first TACE (TACE 1) delivered to the hepatic artery supplying the lobe with the greatest tumor burden. Restaging was performed before TACE 2 and TACE 3, which followed at monthly intervals. PCI-5FU for 21 days was sandwiched between each of the TACE treatments. After the final TACE, maintenance PCI-5FU was given for 28 days of each 35-day cycle until toxicity or progression. Between December 23, 1991, and January 19, 1995, 32 patients were registered in this trial, of whom 27 were eligible; 20 completed one or more treatment cycles and were evaluable for radiographic response. Patients with colorectal liver metastases predominated (74%). Twelve (44%) of 27 patients had failed one or more prior treatment regimens. There were no treatment-related deaths, and hematological and hepatic toxicities were generally manageable and reversible. Two patients, however, developed hepatic abscesses requiring drainage, and one patient developed an infarcted gallbladder, which necessitated cholecystectomy. There were no patients with complete responses; there were 8 (40%) with partial responses, 4 (20%) with minor responses, 2 (10%) with stable disease, and 6 (30%) who progressed on the treatment. The median duration of response for partial responders was 4.2 months (127 days; range, 56-245 days). The median reduction in carcinoembryonic antigen for responders was 87.5%. Two patients underwent subsequent resection of residual metastases; one of them is still alive at 58.4 months follow-up. The predominant site of disease progression was the liver; 25% of the patients progressed in extrahepatic sites. The median overall survival for the whole group is 14.3 months (95% confidence interval, 7.2-16.2). Actuarial overall survival for the whole group at 1 year and 2 years is 57 and 19%, respectively. Alternating systemic PCI-5FU and regional TACE (cisplatin/polyvinyl alcohol) is an active and feasible regimen with manageable toxicities in patients with metastatic gastrointestinal malignancies with liver-dominant disease and merits further investigation. The complications seen were in line with those reported at other specialized centers. 相似文献