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991.
This paper proposes a new extended Process to Product Modeling (xPPM) method for integrated and seamless information delivery manual (IDM) and model view definition (MVD) development. Current IDM development typically uses Business Process Modeling Notation (BPMN) to represent a process map (PM). Exchange requirements (ERs) and functional parts (FPs) specify the information required when information is exchanged between different activities. A set of information requirements, specifically defined as a subset of Industry Foundation Classes (IFC), is called an MVD. Currently however, PMs, ERs, FPs, and MVDs are developed as separate documents through independent development steps. Moreover, even though ERs and FPs are designed to be reused, tracking and reusing the ERs and FPs developed by others is practically impossible. The xPPM method is proposed to provide a tight connection between PMs, ERs, FPs, and MVDs and to improve the reusability of predefined ERs and FPs. The theoretical framework is based on the approach of the Georgia Tech Process to Product Modeling (GTPPM) to suit the IDM development process. An xPPM tool is developed, and the validity of xPPM is analyzed through the reproduction of existing IDMs and MVDs. The benefits and limitations of xPPM and lessons from the applicability tests are discussed.  相似文献   
992.
Nonaka’s model of knowledge creation can provide guidance for designing learning environments and activities. However, Bereiter is critical of the model because it does not address whether understanding is deepened in the process of socialization, externalization, combination and internalization. To address this issue of understanding, this paper proposed a framework that synthesizes the basic phases of problem-based learning with Nonaka’s model. This paper reports on a study investigating if a course designed based on this authentic framework can help to stimulate knowledge creation based on deepening understanding. Several types of data were collected in this design-based research, namely: reflections by the participants and instructor; group discussions; student-created artifacts; and documents, records and artifacts that reflect the overall design of the course. The findings suggest that the participants demonstrated advancing understanding amidst knowledge creating conditions and processes consistent with Nonaka’s model. Other key implications are also discussed.  相似文献   
993.
The fluorescence in situ hybridization (FISH) technique has been commonly employed to detect the chromosomal abnormalities. However, applications of this technique are limited due to its lengthy process and labor-intensive sample preparation. In this study, a novel integrated microfluidic chip capable of performing the entire FISH protocol automatically was reported. This novel technique can achieve several advantages, including reduce the consumption of bio-samples and reagents, automation and rapid analysis compared to the conventional method. In this study, several functional microfluidic devices were integrated on a single chip to perform automatic FISH on the microfluidic platform. Experimental data demonstrated that the developed microfluidic system successfully provided superior performance for probing the chromosomal abnormality of cells. Furthermore, the novel microfluidic system performed the entire process automatically within 3 h, where the conventional method required 10 h to perform the entire protocol manually. This data indicated superior performance of the novel method. Our findings conclude that the novel integrated FISH protocol is more convenient to perform large quantities of samples, which can be used in clinical trials.  相似文献   
994.
An in-line mixer pH system is proposed to identify the titration curve before changes in the input stream affect the main pH neutralization reactor. It is operated under integral control and shows oscillatory responses for a wide range of controller integral gain. The bifurcation diagram for the change of the controller integral gain is very similar to that of the quadratic map which is often used in illustrating the chaos phenomena of nonlinear processes. Various bifurcation diagrams are obtained as operating conditions of the in-line mixer system such as the set point of pH and components of the input stream change. The integral control keeps oscillations be around the set point, providing plentiful information about the pH process. The oscillations can be used to identify the titration curve of the input acid stream. Simulation and experimental results show that the chaotic operations of a small in-line mixer can be positively used for the identification of the titration curve.  相似文献   
995.
During the last half century, significant efforts have been made to explore the underlying mechanisms of visual selective attention using a variety of approaches—psychology, neuroscience, and computational models. Among them, the computational approach emerged on the stage with the development of computer science and computer vision focusing researchers interests in this area. However, computer scientists often face the difficulty of how to construct a computational model of selective attention working on their own purpose. Here, we critically review studies of selective attention from a multidisciplinary perspective to take lessons from psychological and biological studies of attention. We consider how constraints from those studies can be imposed on computational models of selective attention.  相似文献   
996.
Optimisation modelling of integrated production–distribution (P–D) plans has raised significant interest among both researchers and practitioners over the past two decades. This paper provides the readers with a comprehensive review and critique on the current P–D planning and optimisation literature. We classify the published P–D planning models into seven categories based on their degree of complexity and hence capability in addressing real-life scenarios. Summary tables highlight the main characteristics of the selected models at each category. Next, the paper reclassifies and evaluates the proposed models based on the solution techniques used. Lastly, the unaddressed areas in the current literature are highlighted, important managerial implications are proposed and directions for future research in the area are suggested.  相似文献   
997.
This paper proposes the most feasible solution to overcome the failure of the 2nd harmonic filter in the static VAR compensator (SVC) which operates with the DC electric arc furnace (EAF) at Gwangyang Steel Mill in Korea. In order to investigate the causes of this failure, various measurements were carried out on the DC EAF and the main transformer at the PCC (point of common connection). It was concluded that the two causes for the failure are; the inrush current in the main transformer, and the parallel resonance between the system impedance and the harmonic filter. Three solutions to suppress the transformer inrush current and another three solutions to avoid the parallel resonance are suggested. The feasibility of these solutions was verified through the computer simulation with PSCAD/EMTDC. The most feasible solution to avoid further failures of the 2nd harmonic filter was selected, based on the estimated result for the six optional solutions in the point of performance and cost.  相似文献   
998.
Lead zirconate titanate [PZT(60/40)] films were deposited by RF-magnetron sputtering using single oxide targets with various levels of excess PbO. The excess PbO in the film played an important role in the pyrochlore-to-perovskite transformation, nucleation and growth processes, orientation control, and crack formation. When 5% or 20% excess PbO was added to the target, pyrochlore phases were created and the films were severely cracked. However, the films had a perovskite structure without any pyrochlore phases when 10% or 15% excess PbO was added to the targets. More interestingly, the crystallographic orientation was strongly dependant on the excess PbO content. A film with a (111) preferred orientation was produced when 10% excess PbO was added to the target. On the other hand, a film with a (100) preferred orientation was deposited by the target with 15% excess PbO. The dielectric, ferroelectric and piezoelectric properties of these films with different orientations and microstructures were examined and correlated with the film structure.  相似文献   
999.
This paper describes a research approach based on the Actor-Network Theory (ANT) to interpret and understand the Korea’s strategy for the development of the ubiquitous city (u-city). Analyzing empirical materials from u-city development, this study traces and unpacks the interaction occurring around the u-city innovation and also identifies patterns of innovation, concentrating on negotiation and translation implementation. The findings imply that Korean approach has marginalized key issues relating to the development potential inherent in the combination of knowledge and technology and thus conflicts with broader development suggestions of participative design. Korean case reveals the essential role of participatory design in u-city development. U-city as a public utility should draw users’ perspectives, its design should be heavily grounded in users’ needs, and its design decisions should be based on a community consensus.  相似文献   
1000.
M-ary phase-silence-shift-keying (PSSK), one of power-efficient modulation schemes, has enhanced symbol error rate (SER) performance by 6 dB compared with that of the conventional phase-shift-keying (PSK). Phase tracking problem of the PSSK with phase-locked-loop (PLL) is discussed in this paper. Capacity of the PSSK for the additive white Gaussian noise (AWGN) channel and Rayleigh fading channel is analyzed. Capacity loss of the PSSK due to the PLL is small, which tells us that the PSSK demodulator can be practically implemented.  相似文献   
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