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941.
A Program for Outliers Elimination in Multidimensional Space (POEMS), which allows the user to eliminate outliers from training spaces as a prior step to any statistical study, is presented. Even though the program can be applied to any scientific field, the characteristics of POEMS makes it particularly suitable for 'series design' on Quantitative Structure-Activity Relationships studies.  相似文献   
942.
The authors discuss the Macintosh Programmer's Workshop (MPW), a Macintosh development environment that includes a comprehensive set of programming tools and handles several languages. It also combines the graphical interface common to all Macintosh applications, a command language similar to the Unix shell languages, and Smalltalk's immediate execution of commands in any window. They focus on the program-development environment rather than on the tools in that environment. They give the history of MPW, and describe its design goals. The bulk of the article is a discussion of MPW's design  相似文献   
943.
Recombinant cytochrome b5 was extracted into the reversed micelle phase of an anionic surfactant (AOT) in octane and back-extracted to a final aqueous phase. The extraction of the protein was controlled by an electrostatic mechanism, since it was dependent on the global charge of the protein. This was directly demonstrated by experiments with native and mutant cytochromes obtained by site directed mutagenesis. The back-extraction of cytochrome b5 to a fresh aqueous phase was decreased by factors that reduced the size of the water pool of the organic phase, such as high salt concentrations (1–2 mol dm?3 NaCl) and low temperatures (4°C), probably because of an increase in a favourable interaction of this protein with the surfactant at closer distances.  相似文献   
944.
This paper describes a stack for the Apple Macintosh Hypercard environment that facilitates the calculation of a set of thermodynamically-corrected pH buffers. Presented in the familiar Macintosh mouse-based environment, the program allows comprehensive buffer design and gives the user full control of buffer species, temperature, ionic strength, pH and choice of counter-ion to maintain the ionic strength at a fixed value. Addition of new buffers to the stack is straightforward and the recipes that are generated, including the weights of the various components, can be displayed on the screen or saved to a disk file for subsequent printing.  相似文献   
945.
Function plotting using conic splines   总被引:1,自引:0,他引:1  
  相似文献   
946.
Optical frequency-shift-keying (FSK) signals are obtained from directly modulated distributed feedback (DFB) semiconductor lasers. Experimental studies of the direct frequency modulation (FM) characteristics of the DFB lasers show a nonuniform FM response due to the competing effects of thermal modulation of the laser active region and carrier density modulation. Equalization of the signal current to the laser is employed to produce a flat FM response from 30 kHz to 1 GHz. Optical FSK transmission and heterodyne detection experiments at 560-Mbit/s and 1-Gbit/s are conducted at a wavelength of 1497 nm. Receiver sensitivities of -39 dBm at 560 Mbit/s and -37 dBm at 1 Gbit/s are obtained. Transmission through 100 km of single-mode fiber at 1 Gbit/s is achieved with no degradation in receiver sensitivity.  相似文献   
947.
A model concept for prediction of sulfide buildup in sewer networks is presented. The model concept is an extension to--and a further development of--the WATS model (Wastewater Aerobic-anaerobic Transformations in Sewers), which has been developed by Hvitved-Jacobsen and co-workers at Aalborg University. In addition to the sulfur cycle, the WATS model simulates changes in dissolved oxygen and carbon fractions of different biodegradability. The sulfur cycle was introduced via six processes: 1. sulfide production taking place in the biofilm covering the permanently wetted sewer walls; 2. biological sulfide oxidation in the permanently wetted biofilm; 3. chemical and biological sulfide oxidation in the water phase; 4. sulfide precipitation with metals present in the wastewater; 5. emission of hydrogen sulfide to the sewer atmosphere and 6. adsorption and oxidation of hydrogen sulfide on the moist sewer walls where concrete corrosion may take place.  相似文献   
948.
This paper describes the ePerSpace research project which aims to significantly increase user acceptance of networked audiovisual systems and applications at home and virtually anywhere by enabling innovative interoperable value-added personalised networked services and applications. Moreover, it aims to develop an open architecture and a framework that will significantly increase the speed of developing novel value-added personalised services by reusing well-defined system components with open APIs. The structure of the paper follows the methodology of the project. It starts with a vision of future personalised services from the users’ perspective by developing five scenarios. These scenarios are then used to extract the requirements of the personalisation framework which is then described in terms of its personalisation, service management, digital home environment management and content adaptation capabilities.  相似文献   
949.
950.
Post-treatment of an UASB reactor effluent, fed with domestic sewage, was conducted using two-stage flotation and UV disinfection. Results were compared to those obtained in a parallel stabilisation pond. The first flotation stage employed 5 - 7.5 mg L(-1) cationic flocculant to separate off more than 99% of the suspended solids. Then, phosphate ions were completely recovered using carrier flotation with 5-25 mg L(-1) of Fe (FeCl3) at pH 6.3-7.0. This staged flotation led to high recoveries of water and allowed us to separate organic matter and phosphate bearing sludge. The water still contained about 1 x 10(2) NMP/100 mL total coliforms, which were removed using UV radiation to below detection levels. Final water turbidity was < 1.0 NTU, COD < 20 mg L(-1) O2 and 71 mNm(-1), the liquid/air interfacial tension. This flotation-UV flowsheet was found to be more efficient than the treatment in the stabilisation pond and appears to have some potential for water reuse. Results were discussed in terms of the biological, chemical and physicochemical mechanisms involved.  相似文献   
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