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131.
We examined the relationships between the success of ERP system adoption, extent of business process improvement (BPI), and organizational performance and investigated the associations between the outcomes of these initiatives and such organizational factors as strategic intent, senior management support, and the status of the IT function within a company. A correlation analysis of 96 firms was made to test our hypothesis that the strategic intent to use ERP was closely related to the success of BPI, ERP, and organizational performance. The results also demonstrated that CEO-IT distance may have little direct bearing on the outcomes of ERP and BPI initiatives. A closer CEO-IT reporting relationship, however, was found to be associated with higher levels of senior management support for both types of enterprise projects. This empirical evidence reinforced the long-held assumption that organization-level benefits, BPI, and ERP success were closely related; and that these relationships were subject to the influence of the organizational variables.  相似文献   
132.
在IP网络中,虚拟机跨子网迁移后其网络地址发生了变化,将面临IP移动性问题。主要研究如何在未来网络体系结构—XIA(expressive internet architecture)中解决这一问题。利用XIA中标识与地址分离、基于DAG(directed acyclic graphs)的灵活路由等特性,提出了基于集合点代理的虚拟机在线迁移方法,并进行了具体实现和实验验证。结果表明,所提出的方法可满足虚拟机迁移后与通信对端网络连接的快速恢复,并具备控制平面简单和数据平面高效的优点。  相似文献   
133.
This paper proposes camera and media stream management techniques at the middleware level for implementing a U-City (ubiquitous city). The study focuses on overcoming the difficulties associated with developing middleware capable of processing and streaming multimedia data from a large number of cameras by expanding the traditional media processing technology. The content of the study can be classified into two main categories: One is a camera array management technique that involves the middleware-level framework and protocol for managing the camera array. The other is the media stream management technique for effective delivery management and processing of the multimedia streams from the camera array.
Chuck YooEmail:
  相似文献   
134.
Surfaces of commercial sheet molded composite (SMC) materials have been characterized by X-ray photoelectron spectroscopy (XPS) before and after various surface treatments. Surface treatments included cleaning with methylene chloride, abrasion using methylene chloride and a Scotch Brite ® abrasive pad, and application of an isocyanate primer. The pretreated SMC materials were bonded using a polyurethane adhesive. Bonded coupons were tested under a variety of conditions using the lap shear technique. Lap shear test results for specimens bonded following the abrasion and primer pretreatment indicated a favorable fracture force and mode of failure. Surface analysis studies were used to characterize the pretreated and failed surfaces.  相似文献   
135.
The potential capability of improving overall elastic modulus of nanotube-reinforced composites is a fundamental concern in nanotechnology applications. Based on geometric analysis and micromechanics estimation, this study reports that the ratio of surface-to-surface distance of adjacent carbon nanotubes (CNTs) to the CNT diameter plays a key role in improving the overall elastic modulus of the CNT-reinforced composites when the tubes are perfectly aligned, completely separated from other tubes, and ideally bonded with the composite matrix. With the decrease of this ratio, that is, decrease of the surface-to-surface distance of adjacent CNTs and/or increase CNT diameter, the improvement capability increases. However, theoretical and experimental results show that an increase of the CNT diameters degrades the elastic moduli of CNTs. This paper discusses the criterion of choosing CNTs with larger diameter and addresses the factors influencing the surface-to-surface distance of adjacent CNTs.  相似文献   
136.
使用仪表放大器电路时最常遇到的应用问题之一是缺乏为仪表放大器的输入偏置电流提供一个DC返回路径。这种问题常常发生于仪表放大器的输入是电容耦合时。输入偏置电流迅速地对  相似文献   
137.
Resin transfer molding (RTM) is considered one of the most promising composite fabrication techniques because of its relatively low equipment and tooling costs, short cycle times, and excellent design flexibility. Yet several technical issues impede wider application for this process. One of those issues is the measurement and characterization of fiber preform permeability, which plays a key role in process design and control. In this study, an automatic permeability measurement apparatus with automatic data acquisition and processing capabilities has been developed to improve measurement accuracy and reliability. Four major factors and their effects on permeability for a knitted and a woven fabric performs are investigated. Design of experiments, ANOVA analysis, and distribution characterization techniques are used to analyze the permeability‐influencing factors and statistical properties of fiber preform permeability. It is found that the fiber preform permeability values vary significantly for different mold shapes and fiber handling conditions. It is also revealed that permeability values for both fabrics follow normal distributions, even though their means and variances are different. These results can be used to better understand the behavior of the RTM process and to improve process design and control.  相似文献   
138.
With growing interest in oleaginous yeast as producers of future fuels and bulk chemicals, a robust, high‐throughput method for estimating lipid production is required. Although the lipophilic dye Nile red is frequently used to assay large samples of yeast and microalgae, inconsistent stain permeability between species and strains limits its effectiveness for some microorganisms. In this study, the oleaginous yeast Metschnikowia pulcherrima is used to develop a fluorescence‐free, cell‐size‐based image analysis method for estimating lipid production, which is then compared with an optimized Nile red method across several experimental scenarios. Cell size analysis (CSA) outperforms Nile red in all scenarios, correlating well with lipid extraction data when screening multiple strains, screening a subset of strains grown in different conditions, and tracking the lipid accumulation of a culture over time. Stain permeability is shown to vary significantly among the strains trialled, with lipid droplet size and cell wall thickness having a deleterious effect in the permeability of high‐lipid‐accumulating cells. CSA can also allow culture population dynamics to be monitored, providing key process information of cell size distribution in response to changing media compositions. Practical Applications: Nile red is currently the go‐to method for high‐ throughput lipid screening; however, staining inconsistencies in some organisms caused by varying cell morphology makes it challenging to optimize a robust protocol. Although fluorescence‐free methods exist (Raman spectroscopy, Fourier‐transform infrared spectroscopy, GCMS), the need for extensive sample preparation and specialist equipment restricts their widespread adoption. The CSA method presented here offers an accurate, robust, and cheap alternative for the study of microorganisms where fluorescence‐based avenues are not feasible. Furthermore, the population dynamics collected during CSA can easily be applied to bioreactor style processing, where tracking size distributions can provide real time information of culture status. This additional information is valuable even if fluorescence screening is a possibility.  相似文献   
139.
140.
Seed legumes have played a major role as a crop worldwide, being cultivated on about 12% to 15% of Earth's arable land; nevertheless, their use is limited by, among other things, the presence of several antinutritional factors (ANFs ‐ naturally occurring metabolites that the plant produces to protect itself from pest attacks.) Trypsin inhibitors (TIs) are one of the most relevant ANFs because they reduce digestion and absorption of dietary proteins. Several methods have been developed in order to inactivate TIs, and of these, thermal treatments are the most commonly used. They cause loss of nutrients, affect functional properties, and require high amounts of energy. Given the above, new processes have emerged to improve the nutritional quality of legumes while trying to solve the problems caused by the use of thermal treatments. This review examines and discusses the methods developed by researchers to inactivate TI present in legumes and their effects over nutritional and functional properties.  相似文献   
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