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21.
Enterprise resource planning (ERP) systems enable firms to attain information technology integration. Such integration results in a uniform information system across the entire organization, thus augmenting performance. in this article, the issues and performance of Oracle ERP are discussed based on perspicacious exploratory analyses conducted in two manufacturing firms located in Ohio and Wisconsin. the factors of influence to implement Oracle ERP systems, various issues involved in the process of implementation, and performance of the systems are discussed in detail. the triangulation technique was used to make sure that the qualitative and quantitative findings were congruent. the results of the quantitative analysis and details of the constructs and items identified to measure the constructs are explained elsewhere by the first author. Oracle ERP systems enabled these firms to perform better by simplifying and streamlining their information retrieval and dissemination processes. Oracle's Web-based network computing architecture (NCA) offers many advantages, such as higher scalability and better coordination with suppliers and customers. These case studies provided a foundation for future research to build theoretical models.  相似文献   
22.
Rietveld analysis of powder neutron diffraction pattern recorded on Sr-based 1201-phase superconductor (T c =53 K), (Hg0.7Cr0.3)Sr2CuO4+δ shows that the oxygen atoms at O(3) site are disordered atx=y=0.3712. This fourfold split site has a total combined occupancy of ~80% and is the only occupied site in the (Hg, Cr)O plane.  相似文献   
23.
Rana P  Mohan N  Rajagopal C 《Water research》2004,38(12):2811-2820
A study has been carried out to determine the feasibility of electrochemical removal of chromium ions from industrial wastewater using carbon aerogel electrodes. In this work the effect of key variables including pH (2-7), concentration 2-8 (mg/l), and charge 0.3-1.3 (A h) was determined. The metal ion removal was significantly increased at reduced pH and high charge conditions. The metal concentration in the wastewater can be reduced by 98.5% under high charge (0.8A h) and acidic conditions (pH 2). The effect of the independent parameters--pH, effluent concentration and charge on the percentage removal was depicted by a quadratic equation obtained using Box-Behnken model. The regression analysis gave a R2 value of 0.9469 shows a close fit between the experimental results and the model predictions. The model was further used to optimise the parameters to maximise the percentage Cr-removal to more than 98%.  相似文献   
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Mussel control in cooling water systems is generally achieved by means of chlorination. Chlorine is applied continuously or intermittently, depending on cost and discharge criteria. In this paper, we examined whether mussels will be able to survive intermittent chlorination because of their ability to close their valves during periods of chlorination. Experiments were carried out using three common species of mussels: a freshwater mussel, Dreissena polymorpha, a brackish water mussel, Mytilopsis leucophaeata and a marine mussel, Mytilus edulis. The mussels were subjected to continuous or intermittent (4 h chlorination followed by 4 h no chlorination) chlorination at concentrations varying from 1 to 3 mg l(-1) and their responses (lethal and sublethal) were compared to those of control mussels. In addition, shell valve activity of mussels was monitored using a Mussel-monitor. Data clearly indicate that mussels shut their valves as soon as chlorine is detected in the environment and open only after chlorine dosing is stopped. However, under continuous chlorination mussels are constrained to keep the shell valves shut continuously. The mussels subjected to continuous chlorination at 1 mg l(-1) showed 100% mortality after 588 h (D. polymorpha), 966 h (Mytilus edulis) and 1104 h (Mytilopsis leucophaeata), while those subjected to intermittent chlorination at 1 mg l(-1) showed very little or no mortality during the same periods. Filtration rate, foot activity index and shell valve movement of D. polymorpha, Mytilopsis leucophaeata and Mytilus edulis decreased more than 90% at 1 mg l(-1) chlorine residual when compared to control. However, mussels subjected to intermittent chlorination showed a similar reduction (about 90%) in filtration rate, foot activity index and shell valve movement during chlorination and 3% during breaks in chlorination. The data indicate that intermittent chlorination between 1 and 3 mg l(-1) applied at 4 h on and 4 h off cycle is unlikely to control biofouling if mussels are the dominant fouling organisms.  相似文献   
26.
The laboratory and field test data on the response of piles under the combined action of vertical and lateral loads is rather limited. The current practice for design of piles is to consider the vertical and lateral loads independent of each other. This paper presents some results from three-dimensional finite-element analyses that show the significant influence of vertical loads on a pile’s lateral response. The analyses were performed in both homogeneous clayey soils and homogeneous sandy soils. The results have shown that the influence of vertical loads on the lateral response of piles is to significantly increase the capacity in sandy soils and marginally decrease the capacity in clayey soils. In general, it was found that the effect of vertical loads in sandy soils is significant even for long piles, which are as long as 30 times the pile width, while in the case of clayey soils, the effect is not significant for piles beyond a length of 15 times the width of the pile. The design bending moments in the laterally loaded piles were also found to be dependent on the level of vertical load on the piles.  相似文献   
27.
There are a number of situations where the deformed configuration of a body is known and it is necessary to determine the reference state. Previous methods developed to calculate the reference state involve the formulation of the finite elasticity equations in terms of the deformed configuration. This paper demonstrates that the undeformed reference state can be accurately determined from a deformed configuration and the associated loading conditions, by using conventional finite elasticity balance equations together with a solution procedure that treats the reference configuration as the unknowns. The mathematical theory behind the solution method is described, validated with an analytical solution, and verified using experimental studies on gel phantoms. The practical utility of this method is then demonstrated in the field of breast biomechanics. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
28.
We report synthesis, characterization and ion transport in polyether-based ionic melt electrolytes consisting of Li salts of low-basicity anions covalently attached to polyether oligomers. Purity of the materials was investigated by HPLC analysis and electrospray ionization mass spectrometry. The highest ionic conductivity of 7.1 × 10−6 S/cm at 30 °C was obtained for the sample consisting of a lithium salt of an arylfluorosulfonimide anion attached to a polyether oligomer with an ethyleneoxide (EO) to lithium ratio of 12. The conductivity order of various ionic melts having different polyether chain lengths suggests that at higher EO:Li ratios the conductivity of the electrolytes at room temperature is determined in part by the amount of crystallization of the polyether portion of the ionic melt.  相似文献   
29.
We show that models for the nonlinear viscoelastic response of solids generated on the basis of a correspondence principle developed by Schapery(1984) do not satisfy the balance of angular momentum for large deformations. This principle, which is valid if the displacement gradients are sufficiently small, has been used in several papers to develop models to describe the fracture of viscoelastic solids, and these studies need to be reexamined in the light of this note.  相似文献   
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