This article presents the opportunities and challenges for improving resilience in an oil distribution plant. The plant is situated in the southernmost state of Brazil, and it distributes fuel products by truck and tr...
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This article presents the opportunities and challenges for improving resilience in an oil distribution plant. The plant is situated in the southernmost state of Brazil, and it distributes fuel products by truck and train. Based on observations and interviews with the people who handle the transfer and distribution process, this paper provides an analysis of how the system is resilient in some ways and brittle in other ways. The research focused on understanding how the system adapts to variations and disrupting events relative to expected conditions. The areas of brittleness are pointers to possible accident scenarios. The resilience analysis identified opportunities to improve how the system adapts to situations that challenge plans and procedures
Research and discussion into more efficient utilization of frequency spectrum has led to a paradigm shift in future allocation and utilization of spectral resources in the frequency band of licensed (primary) systems....
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Research and discussion into more efficient utilization of frequency spectrum has led to a paradigm shift in future allocation and utilization of spectral resources in the frequency band of licensed (primary) systems. Secondary usage of licensed spectrum is being considered as a viable solution to the problem of inefficient usage of spectral resources. In this paper, we model and analyze the performance of the secondary system in dynamic spectrum access by secondary users employing an overlay approach of sharing spectral resources with a primary system. Our model assumes the operation of primary system is completely unaffected by the introduction of a secondary system, i.e., primary users have priority in transmission over secondary users. Each primary user is randomly assigned an available frequency slot for transmission by the primary system controller. Secondary users are required to sense across the same spectrum to identify any unoccupied frequency slots for transmission. During its transmission, if it detects a primary user accessing the same frequency slot, the connection will be forced to drop. Using a three-dimension Markov chain model, this paper presents an analytical approach to study the secondary system performance under a given primary traffic. Two important parameters that are indicative of the grade-of-service (GoS) of the secondary system, namely, secondary call blocking probability and secondary call dropping probability are computed using the model presented. The analysis provides an insightful study about how the secondary system capacity is determined by its GoS requirement. We use the same analytical approach to show that when the secondary call dropping probability is the cause of low capacity, by suitably reserving a number of frequency slots for primary users' access, the secondary system capacity can be improved significantly
We present the use of the polysaccharide chitosan for immobilizing biomolecules on microfabricated device surfaces. The main advantages of chitosan are its abundance of primary amine groups and its ability to be elect...
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ISBN:
(纸本)1424402778
We present the use of the polysaccharide chitosan for immobilizing biomolecules on microfabricated device surfaces. The main advantages of chitosan are its abundance of primary amine groups and its ability to be electrodeposited. Biomolecules are easily attached to chitosan 's amines by standard glutaraldehyde chemistry. The electrodeposition of chitosan allows accurate spatial and temporal control of biomolecule placement. We have demonstrated this biofunctionalization method for two different bioMEMS devices: a biophotonic sensor and a micromechanical biosensor. We have successfully assembled probe DNA on each of them and detected hybridization with target DNA as a demonstration of sensor operation. Here, we briefly present the fabrication procedure and testing results for both of these bioMEMS sensing devices
The authors created a Web-based integrated education support system that unified the data in the administrative system and the education system in a university. The purpose of the system was to make the administrative...
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In the coastal catchments of Shandong Province the water scarcity is aggravated due to saltwater intrusion, reducing the usability of water resources available. Such a situation calls for sustainable integrated water ...
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In the coastal catchments of Shandong Province the water scarcity is aggravated due to saltwater intrusion, reducing the usability of water resources available. Such a situation calls for sustainable integrated water resources management (IWRM). The idea for the objectives and implementation of the IWRM are explained in this paper. The general objective of the planned project disscussed in the present study is to bring together German traditional expertise in water resources management and newer developments in the context of the European Water Framework Directive; the research efforts aim to relieve the desperate water scarcity situation in the costal area of Shandong Province.
We have utilized ZnCl 2 -dimethylsulfone (DMSO 2 ) as the electrolyte with added CoCl 2 and GdCl 3 for electrodepositing a magnetic film. Moreover, the controlled potential method was utilized for film deposition. T...
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We have utilized ZnCl 2 -dimethylsulfone (DMSO 2 ) as the electrolyte with added CoCl 2 and GdCl 3 for electrodepositing a magnetic film. Moreover, the controlled potential method was utilized for film deposition. The voltammogram revealed that the reduction of Co-Zn-Gd film can be achieved by applying a potential in the range from -0.1 to -0.5 volts. From the results of AGM analyses, a high squareness value (Mr/Ms = 0.923) of the Co-Zn-Gd film at -0.3 volt was observed. In previous research, perpendicular magnetic materials have been applied to magnetic optic (MO) media, magnetic recording heads, and perpendicular magnetic tunneling junction (pMTJ). However, preparation of magnetic materials is normally carried out in high vacuum systems. Since electrodeposition methods for preparation of magnetic films have several advantages, such as simple equipment, ease of operation and relatively large area, the use of electrodeposition has great potential for preparing films.
The multi-stage, multi-machine capacitated lot-sizing problem (MSMMCLSP) consists of scheduling the production of one product in a multi-machine production system with a multi-stage structure. This study first propose...
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The multi-stage, multi-machine capacitated lot-sizing problem (MSMMCLSP) consists of scheduling the production of one product in a multi-machine production system with a multi-stage structure. This study first proposes an improved heuristic for the MSMMCLSP under deterministic demand over a finite planning horizon. Eliminating overloads by shifting the end item (e.g., all components) backward to a past period or forward to a future period, it uses Wagner-Whitin/lot-for-lot rescheduling to ensure schedule feasibility and uses an improving procedure to improve the scheduling of components in lower stages of production. Preliminary examination, however, revealed that this does not always optimize production schedules as well as the heuristic of Franca et al.[l] does. We therefore developed an integrated heuristic that guarantees a better solution for general MSMMCLSP by combining the heuristic of Franca et al. and the improved heuristic. We also evaluate the effectiveness of the proposed heuristics by using a simulation test with various planning parameters.
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