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21.
One of the challenges facing professionals in the environmental arena today is the collection and assessment of large amounts of environmental analytical data. The assessment of the quality of that data is essential as multi-million dollar decisions for environmental site cleanups and/or long term monitoring efforts are made based on the analytical results. Also critical to environmental programs is the sharing and access of data across multiple data users. The ability to share data allows for better use of the limited resources available to clean up and monitor contaminated environmental sites. Standardization of electronic deliverables allows for collection of data from multiple data collectors into a single database for use by numerous data users and stakeholders on a project. This paper discusses the benefits of using a standard EDD deliverable format and use of environmental data assessment software tools to do project planning and data assessment throughout the duration of the environmental project. 相似文献
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In enterprises decisions whether to undertake investments into IT projects or not have to be made regularly. Regarding the fact that two out of three IT projects fail or do not reach their expected value the need for an integrated valuation which addresses returns and connected risks is evident. The impact of development aspects (e.g. the process model used) and project size on the risk-return position of IT projects is demonstrated and it is shown how this can be taken into account when valuing, optimizing and selecting IT investments. 相似文献
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Wehrmann F. Harizi C. Herrmann H. Rust U. Sohler W. Westenhofer S. 《IEEE journal of selected topics in quantum electronics》1996,2(2):263-269
Fully packaged, polarization independent, integrated acoustooptic 2×2 switches have been developed which can be also used as add/drop multiplexers. The devices have been fabricated in X-cut Y-propagating LiNbO3 and can be operated at wavelengths around 1550 nm. They consist of passive polarization splitters and acoustooptic TE-TM converters with weighted coupling. A filter bandwidth of 2.0 nm and a tuning range of 130 nm have been obtained. The fiber-to-fiber insertion loss is <4.6 dB and a residual polarization dependence of 1.3 dB for bar-state and 0.1 dB for cross-state routing has been achieved 相似文献
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M Wehrmann A Greschniok S Offenhaeuser B Bueltmann 《Canadian Metallurgical Quarterly》1994,2(5):237-240
Today, local therapy is an established alternative to radical resection for the treatment of rectal tumours. Selection of the operative technique requires an exact perioperative estimation of risks, with both clinical and histopathological examination. Of crucial importance in making a decision to perform a local resection is exact and meticulous histopathological preparation of the tissue. The most important criterion is the estimation of risk of lymph node metastases. This risk is assessed on the basis of the depth of invasion of the tumour, the histological grade of differentiation and the presence or absence of invasion of lymphatic vessels. 相似文献