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991.
This paper presents an optimization procedure which has been developed to select appropriate suspension design parameters for a simple two wheel trailer. A modern approach to the optimization problem has been used applying non-linear programming to the constrained search for the minimum of an objective function. The acceleration response to roadway input of selected points on the load of the trailer has been designated for minimization. This acceleration has an important significance to the trailer design because of its effect on the stable and smooth ride of the trailer. Two computational procedures have been used and the results compared. The first approach involves the linear superposition of responses to a series of discrete sinusoidal inputs while the second applies more contemporary random vibration theory using power spectral density curves to simulate the actual road surfaces. The results of the optimization procedure are then compared with the response characteristics of the original trailer design and demonstrate that a substantial improvement has been made. 相似文献
992.
Branko Deljanin Dusan Simic Alexander Zaitsev John Chapman Inga Dobrinets Annette Widemann Nicholas Del Re Tara Middleton Elena Deljanin Andrea De Stefano 《Diamond and Related Materials》2008,17(7-10):1169-1178
One of the commercial challenges today in the gem industry is to quickly identify the origin of color in pink diamonds — natural, treated and synthetic by use of standard and advanced gemological instruments.An analytical technique that is used by many gem labs involves UV fluorescence. The principle factors in the technique are the excitation wavelengths and the emission spectra. No systematic study of fluorescence of pink natural diamonds, pink treated and pink synthetic diamonds has been undertaken. This study is mainly focused on using fluorescence techniques to characterize pink diamonds and to compile a reference library of emission spectra. Longwave (LW) and shortwave (SW) fluorescence of 365, 254 and 220 nm illumination were used in a custom built microscope with a fluorescence camera to record images and a spectrometer to record spectral data with which to establish a correlation with the cause of color.Other advanced instruments (CL imaging, UV–VIS–NIR, FTIR, PL spectroscopy and electrical conductance) were used to establish additional criteria for distinguishing natural, treated and synthetic pink diamonds and to find a correlation with the “EGL USA CIS (Cross-reference Identification System) fluorescence method”. 相似文献
993.
Alexander S. Lopez Victor C. Quesnel 《Journal of the science of food and agriculture》1976,27(1):85-88
Chromatographic evidence is presented to show that a methyl-S-methionine sulphonium salt is present in fermented and dried cacao. It is extremely labile and readily decomposes to dimethyl sulphide which contributes to chocolate aroma. 相似文献
994.
Colin T. Whittemore Alexander G. Taylor 《Journal of the science of food and agriculture》1976,27(3):239-243
Deoiled herring silage contained an average of 17.6% dry matter (DM) and per 100 g DM: 1.86 MJ GE, 12.1 g N, 5.5 g available lysine and 3.7 g oil. The apparent digestibility coefficients for growing pigs of gross energy (GE) and nitrogen (N) for a diet containing 25% herring silage DM and 75% barley meal DM were 0.83 and 0.91, and the efficiency of retention for digested N was 0.42. The digestible energy (DE) value for the deoiled herring silage was 17.9 MJ DE/kg DM and the digestible nitrogen (DN) value was 119 g DN/kg DM. 相似文献
995.
Alexander J. Macleod Rashida Islam 《Journal of the science of food and agriculture》1976,27(8):721-725
Using previously reported methods of sample preparation an essence of coriander leaf was obtained which proved to contain over 25 components. Most of these have been identified, with aliphatic aldehydes providing nearly 90% of the sample. C12 aldehydes are the most abundant. 相似文献
996.
Alexander J. Macleod Rashida Islam 《Journal of the science of food and agriculture》1976,27(10):909-912
Using previously reported methods of sample preparation an essence of garden cress was obtained which proved to contain only 11 components. Eight have been identified, all glucosinolate degradation products (isothiocyanates and nitriles), and provide over 95% of the sample. Benzyl derivatives, from glucotropaeolin, are the most abundant. No thiocyanates were obtained. 相似文献
997.
Norman A. Matheson Alexander W. Moir 《Journal of the science of food and agriculture》1976,27(10):959-961
A method is described by which the S-methylcysteine sulphoxide content of plant material may be determined approximately in a large number of samples with little labour, apparatus or staff. The presence of SMCO in some plants and its absence in others was confirmed and the method was sufficiently sensitive to reveal varietal differences within a species. 相似文献
998.
Decentralised water supply systems are becoming increasingly affordable and commonplace in Australia and have the potential to alleviate urban water shortages and reduce pollution into natural receiving marine and freshwater streams. Learning processes are necessary to support the efficient implementation of decentralised systems. These processes reveal the complex socio-technical and institutional factors to be considered when developing an enabling environment supporting decentralised water and wastewater servicing solutions. Critical to the technological transition towards established decentralised systems is the ability to create strategic and adaptive capacity to promote learning and dialogue. Learning processes require institutional mechanisms to ensure the lessons are incorporated into the formulation of policy and regulation, through constructive involvement of key government institutions. Engagement of stakeholders is essential to the enabling environment. Collaborative learning environments using systems analysis with communities (social learning) and adaptive management techniques are useful in refining and applying scientists' and managers' knowledge (knowledge management). 相似文献
999.
As the economy becomes global and ICT-reliant, approaches practiced in enterprise software product development and enterprise resource planning (ERP) system implementation must cope with increasingly complex situations induced by contemporary supply chain and regulations. Compliance with regulations in the market is one aspect of the requirements that enterprise software must meet. Recent research of KPMG IT Advisory has confirmed that where little attention is being paid to the value-added tax (VAT) issues during large ERP projects, there is a higher VAT-risk exposure. In a design-oriented approach, we first identify the stakeholders and their interests in the VAT compliance of ERP systems. Enterprise architecture (EA) and model driven engineering in a multi-level perspective serve as the source of solution patterns. The efficient solution of compliance problems builds upon stakeholders utilizing a set of interdependent models and methods that are suitably allocated to the public and proprietary domains. 相似文献
1000.
The exact mechanisms relating exposure to ultraviolet (UV) radiation and elevated risk of skin cancer remain the subject of debate. For example, there is disagreement on whether the main risk factor is duration of the exposure, its intensity, or some combination of both. There is also uncertainty regarding the form of the dose-response curve, with many authors believing only exposures exceeding a given (but unknown) threshold are important. This paper explores methods to estimate such thresholds using hierarchical spatial logistic models based on a sample of a cohort of x-ray technologists for whom self-reports of time spent in the sun and numbers of blistering sunburns in childhood are available. A preliminary goal is to explore the temporal pattern of UV exposure and its gradient. Changes would imply that identical exposure self-reports from different calendar years may correspond to differing cancer risks. 相似文献