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1.
Recent natural disasters have led crisis management organizations to revise their protocols so as to rely on the contribution of a wider range of actors, including simple citizens as well as expert operators, to support decision making activities. Reliable and timely information sharing among members of distributed teams of disaster responders has become paramount for the success of the overall crisis management process. In this paper we propose a crisis management system based on spreadsheet-mediated collaboration among on-site responders and decision makers. To share data a common spreadsheet artifact has been developed by using a participatory design approach which is accessed through mobile user interfaces. The evaluation results showed that the use of the spreadsheet artifact has resulted in more effective decision making relating to set of earthquake management scenarios in high-risk areas located in Italy.  相似文献   
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In most of the literature it is claimed that the number of phase states in CPM is equal to q if p is even, and 2q if p is odd, where the modulation index h=p/q. It is shown that a simple assumption due to Fornery (1973) leads to a simplified finite-state representation and also that CPM has q phase states.<>  相似文献   
4.
Throughout Europe there is an increasing trend of connecting high penetrations of wind turbines to the transmission networks. This has resulted in transmission system operators revising their grid code documents for the connection of large wind farms. These specifications require large MW capacity wind farms to have the ability to assist in some of the power system control services currently carried out by conventional synchronous generation. These services include voltage and frequency control. It is now recognized that much of this new wind generation plant will use either fixed speed induction generator (FSIG)‐ or doubly fed induction generator (DFIG)‐based wind turbines. The addition of a control loop to synthesize inertia in the DFIG wind turbine using the power electronic control system has been described. The possibility of deloading wind turbines for frequency response using blade pitch angle control is discussed. A pitch control scheme to provide frequency response from FSIG and DFIG wind turbines is also described. A case study of an FSIG wind turbine with frequency response capabilities is investigated. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
5.
The adsorption of carbon monoxide (CO), propane (C3H8) and propene (C3H6) on V2O3(0001) films grown on Au(111) was studied by Temperature Programmed Desorption (TPD) and X-ray Photoelectron Spectroscopy (XPS). The “oxidized” surface (i.e., as prepared exhibiting V=O termination), the “reduced” surface (i.e., V=O groups being removed by electron irradiation), as well as the oxygen pre-covered reduced surface were investigated. Both TPD and XPS indicate that the oxidized surface has little affinity for CO adsorption, while the reduced surface readily binds CO (CO amount approx. 10 times higher). Accordingly, CO can be used to titrate the presence or absence of vanadyl oxygen (via adsorption on the vanadium atoms) but also of defects like surface oxygen vacancies. For propane and propene, desorption of the parent molecules was the major process, i.e., surface reactions were absent under the applied conditions. When oxygen was pre-adsorbed on the reduced surface, the adsorption properties resembled that of the oxidized surface, i.e., the vanadyl groups were (partially) re-established. TPD and XPS provide a handle to differentiate the binding sites on the V2O3 surface. Dedicated to Prof. Konrad Hayek.  相似文献   
6.
The antioxidant activities of coconut oil extracted under hot and cold conditions were compared. The coconut oil extracted under hot conditions (HECO) contained more phenolic substances than the coconut oil extracted under cold conditions (CECO). The antioxidant potential of HECO was higher than that of CECO as demonstrated by DPPH assay, deoxyribose assay and in vivo assay of serum antioxidant capacity. It is the common belief that virgin coconut oil extracted under cold conditions preserves several thermally unstable antioxidants and, as a result, better beneficial qualities can be expected for virgin coconut oil. However, high temperatures used in the hot extraction of coconut oil favour the incorporation of more thermally stable phenolic antioxidants into coconut oil. Therefore, the consumption of HECO may result in the better improvement of antioxidant related health benefits compared with the consumption of CECO.  相似文献   
7.
A conducting polymer [polypyrrole (PPy)]-based amperometric biosensor fabricated on a platinum-coated nanoporous alumina electrode has been described. This fabricating process introduced artificial porosity into the PPy film, and the template pore sizes were carefully chosen to match the size of the glucose oxidase (GOx) molecule. The $hbox{PF}_{6}^{-}$-doped PPy film was synthesized with 0.05 M pyrrole and 0.1 M $hbox{NaPF}_{6}$ at a current density of 0.3 $hbox{mA/cm}^{2}$ for 90 s. Immobilization was done by physically adsorbing 5 $muhbox{L}$ of GOx on the nanoporous PPy film. Glutaraldehyde (0.1 wt.%, 5 $muhbox{L}$) was used for cross-linking. The synthesized films were characterized by using an electrochemical technique and scanning electron microscopy (SEM). Amperometric responses were measured as a function of different concentrations of glucose at 0.4 V. Nanoporous electrodes lead to high enzyme loading, whereas the use of a cross-linking agent increased stability, sensitivity, reproducibility, repeatability, and shelf life.   相似文献   
8.
Field evaluations demonstrate that the addition of the minor pheromone component (3E,8Z)-tetradecadien-1-yl acetate to the major component (3E,8Z,11Z)-tetradecatrien-1-yl acetate does not significantly increase the trap catches of Tuta absoluta males in the field. The triene acetate itself is highly attractive, catching about 869 ± 255 males per trap in three consecutive nights. The addition of two isomers of the minor component (3E,8Z)-tetradecadien-1-yl acetate, (3E,11Z)-tetradecadienyl-yl acetate and (8Z,11Z)-tetradecadien-1-yl acetate, to the major component (3E,8Z,11Z)-tetradecatrien-1-yl acetate also did not significantly alter the number of the males caught in the traps.  相似文献   
9.
Protein C-terminal hydrazides are useful for bioconjugation and construction of proteins from multiple fragments through native chemical ligation. To generate C-terminal hydrazides in proteins, an efficient intein-based preparation method has been developed by using thiols and hydrazine to accelerate the formation of the transient thioester intermediate and subsequent hydrazinolysis. This approach not only increases the yield, but also improves biocompatibility. The scope of the method has been expanded by employing Pyrococcus horikoshii RadA split intein, which can accommodate a broad range of extein residues before the site of cleavage. The use of split RadA minimizes premature intein N cleavage in vivo and offers control over the initiation of the intein N cleavage reaction. It is expected that this versatile preparation method will expand the utilization of protein C-terminal hydrazides in protein preparation and modification.  相似文献   
10.
Ponerine ants are known to contain mixtures of pyrazines in their mandibular glands. We analyzed the mandibular gland contents of four ponerine species (Odontomachus chelifer, O. erythrocephalus, O. ruginodis, and O. bauri) by gas chromatography coupled with mass spectrometry, and found that each species contains specific mixtures of trisubstituted alkylpyrazines among other volatiles. Attempts to identify alkylpyrazines solely by mass spectral interpretation is unrealistic because spectra of positional isomers are indistinguishable. To avoid misidentifications, we synthesized a large number of reference compounds and compared their mass spectral and gas chromatographic properties with those present in the Odontomachus species under investigation. Most of the compounds identified were 2-alkyl-3,5-dimethylpyrazines. Interestingly, when the third substituent was an isopentyl group, the two methyl groups were found to be located at the 2 and 5 ring positions. Using our data, we recognized several misidentifications in previous publications.  相似文献   
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