共查询到20条相似文献,搜索用时 31 毫秒
1.
Oscar Burgara-Montero José María Ponce-Ortega Medardo Serna-González Mahmoud M. El-Halwagi 《Clean Technologies and Environmental Policy》2012,14(5):925-942
This paper presents a methodology for the optimal synthesis of distributed treatment systems of effluents discharged into a main river to meet water discharge quality constraints. The methodology is based on a new superstructure that is formulated and solved as a multi-objective mixed-integer nonlinear programming model. A material flow analysis technique is used to track the pollutants through the watershed considering the combined effects of the inputs, outputs (i.e., agricultural, residential, industrial, and so on) and the chemical transformations. A disjunctive programming model is implemented for selecting the optimal location of the distributed treatment system. Prior to the optimization and based on the pollutants considered, a discretization approach is implemented to determine from simulation the removal efficiency and the unit cost of given configurations and operating conditions of the selected treatment units. Therefore, the optimization process determines the removal efficiency used to treat the effluents and the flow rate treated. Simultaneous minimization of the total annual cost of the distributed treatment system and the contaminant concentration of the discharge to the catchment of the watershed are considered as two objective functions. Three case studies (one in Mexico and two in Egypt) have been selected to illustrate the methodology. Results show that significant savings can be obtained when the distributed treatment system is implemented. Finally, the proposed methodology can be used for supporting governmental decisions (i.e., it provides the investment required for a specific water quality). 相似文献
2.
This article presents a new methodology to model the time and space evolution of a contaminant in a system of aquifers when certain components of the model, such as the geohydrologic information, the boundary conditions, the magnitude and variability of the sources or physical parameters are uncertain and defined in stochastic terms. The method is based on applications of modern mathematics to the solution of the resulting stochastic transport equations. This procedure exhibits considerable advantages over the existing stochastic modelling techniques. In particular, the semigroup solutions are not restricted to small variances in the stochastic elements (perturbation techniques), unsteady dynamic conditions are specifically considered, time and space randomness may be considered in the sources, the boundary conditions or the parameters, and the methodology reflects a well-posed functional-analytic theory. Several basic example problems are presented in order to illustrate the application of the methodology to the modelling of complex spatially and temporally distributed sources of interest in engineering hydrology today. Further potential applications of the method are very promising. 相似文献
3.
This three part series of papers addresses operational techniques for applying mass integration principles to design in industry
with special focus on water conservation and wastewater reduction. Part 1 covers design techniques for any number of wastewater
streams containing a single contaminant. The technique comprises a two stage graphical approach. In the first stage, the water
pinch diagram is used to identify key design targets (such as the minimum freshwater requirement of the studied system, the
amount of achievable water recycling and reuse and the water quality concentration bottleneck) for the industrial process
of interest. Key practical insights provided by the water pinch diagram are discussed. In the second stage, source–sink mapping
diagrams are used to identify the water recycling and reuse network, and any alternative networks, that achieve the identified
targets. A case study is included to illustrate the proposed methodology.
Electronic Publication 相似文献
4.
New car models are now by law equipped with on-board diagnostic (OBD) systems aimed at monitoring the state of health of strategic components that ensure low levels of polluting exhaust emissions. During development phases, for each new car model, the OBD system must be finely calibrated. This article presents a robust calibration methodology taking into account sources of variability mainly due to production process, operating, and environmental conditions. The methodology enables us to evaluate the false alarm and failure to detect risks intrinsically related to the adopted calibration. An application concerning an upstream oxygen sensor monitored by the OBD is presented. 相似文献
5.
The Design of the Variable Sampling Interval Generalized Likelihood Ratio Chart for Monitoring the Process Mean
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Yiming Peng Liaosa Xu Marion R. Reynolds Jr. 《Quality and Reliability Engineering International》2015,31(2):291-296
This paper considers the problem of monitoring a normally distributed process variable in which some sustained shift in the mean may occur. A generalized likelihood ratio (GLR) control chart with a variable sampling interval (VSI) scheme is proposed to quickly detect a wide range of such shifts. The performance of the VSI GLR chart is evaluated, and the results show that using the VSI feature can greatly reduce the expected detection time. Design methodology for the VSI GLR chart is provided so that practitioners can easily use this chart in applications. An illustrative example is given to explain how to apply the VSI GLR chart. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
6.
This paper describes the methodology and application of a genetic algorithm scheme tailor-made to EPANET, for optimizing the operation of a water distribution system under unsteady water quality conditions. The water distribution system consists of sources of different qualities, treatment facilities, tanks, pipes, control valves, and pumping stations. The objective is to minimize the total cost of pumping and treating the water for a selected operational time horizon, while delivering the consumers the required quantities at acceptable qualities and pressures. The decision variables for each of the time steps that encompass the total operational time horizon include: the scheduling of the pumping units, settings of the control valves, and treatment removal ratios at the treatment facilities. The constraints are: head and concentrations at the consumer nodes, maximum removal ratios at the treatment facilities, maximum allowable amounts of water withdrawals at the sources, and returning at the end of the operational time horizon to a prescribed total volume in the tanks. The model is explored through two example applications. 相似文献
7.
在研究、分析和总结分布式计算机技术与系统实现的基础上,以苏-27战斗机火控雷达天线部件性能测控系统研制过程为例,详细论述了分布式计算机测控系统的实现模式,介绍了一种先进合理的非标测控设备设计解决方案和快捷、低成本的系统实用集成方案。 相似文献
8.
Error performance of distributed space-time codes used for mobile broadcasting systems consisting of multiple base stations is analysed. The base stations are assumed to operate in a simulcast mode, that is they simultaneously transmit the same message using the same carrier frequency. Mobile users within the intersection of the coverage areas, thus, enjoy a small probability of shadowing and a high probability of at least one line-of-sight (LOS) link. In effect, the base stations establish a virtual multiple-antenna system. The use of a distributed space-time code offers an additional spatial diversity gain. Considering a single user with a fixed (random) position, the impact of shadowing and LOS components on the error performance of the system is analysed and compared with a conventional multiple-antenna system with co-located transmit antennas. Specifically, the analysis shows that already a single LOS link significantly improves the overall system performance. In the case of shadowing, huge diversity gains are obtained in the distributed system. In a system with co-located transmitters, however, the performance improvements compared with a single-antenna system are rather small, when shadowing is taken into account. Altogether, it can be concluded that systems with distributed transmitters are typically superior to conventional multiple-antenna systems (due to macroscopic diversity), and that distributed space-time codes are superior to conventional simulcasting (due to microscopic diversity) 相似文献
9.
In the last decade, an area of increasing estuarine research in the New York/New Jersey Harbor has been the identification of toxic contaminant sources, mapping of contaminant levels in water and sediments, and assessment of contaminant accumulation in biota. The accumulation of anthropogenic contamination in the harbor's sediments has occurred for centuries, primarily from land-based municipal and industrial sources. Contaminants from land-based sources introduced into surface waters rapidly become scavenged by suspended particles that then tend to settle to the bottom, primarily in deep areas, such as berths and navigation channels. Several million cubic meters of sediments must be dredged annually to clear navigation channels. In the past, the dredged material was disposed in a designated ocean site. However, in1992, new testing procedures were implemented, and much of the harbor's dredged material was determined to be unsuitable for ocean placement. It is ironic that these restrictions came at a time when the quality of harbor sediments is improving, largely because of pollution controls implemented as a result of the Clean Water Act and other environmental measures put in place by government and industry. For example, the harbor-wide concentration of mercury has decreased to 0.7-0.8ppm, a level that is approaching the pre-industrial background level. Nevertheless, in certain areas of the harbor, there remain sufficiently high concentrations of contaminants to merit concern and to create serious problems for sponsors of dredging projects. Development of a basin-wide sediment management strategy is necessary to guide port decision-makers in their efforts to clean-up contaminant sources, to dredge regional waterways, and to ameliorate the contaminated sediment disposal problem. The backbone of this strategy is the integration of the data from an ongoing field monitoring and modeling program with a parallel investigation of watershed and airshed sources and sinks using industrial ecology methodology. 相似文献
10.
《IEEE transactions on instrumentation and measurement》2008,57(10):2136-2145
11.
R. Besold R. Baran A. Hofmann P. Holleczek R. Mueller 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1986,250(3):534-538
This paper describes an automatic fault monitoring system using a microcomputer. The hardware is based on the Z80 processor and the software on the programming language PEARL. The microcomputer system is able to detect faults in the equipment during data acquisition and provides useful information for the subsequent data evaluation. The results of two applications are discussed. 相似文献
12.
Nicolas Lefaudeux Xavier LevecqGuillaume Dovillaire Jérome BallestaEmeric Lavergne Paul SauvageotLionnel Escolano 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,653(1):164-167
Adaptive optics is now a standard feature for the current ultra high intensity lasers facilities. Aberration induced by both the optical components and the thermal effects in the amplification stages can be corrected with an adaptive optics system to reach both maximum peak energy and fluence. In this article, we present the development of a new technology of deformable mirror. These mirrors are designed taking into account the needs and specificities of ultra intense laser applications. They provide exceptional stability, optical quality and innovative features like scalability and maintenance of the reflective surface. 相似文献
13.
In this paper, a distributed digital measurement architecture for industrial applications is proposed. The architecture is arranged on three hierarchical communication levels: the fieldbus, the intranet, and the Internet. Particular attention has been paid to the lower level, the field level, implemented using a low-priced smart front-end. It is based on the H8/3048F Hitachi microcontroller and embodies a fieldbus interface (I/F). The same board can be linked to a VXIbus controller by means of a suitable register-based interface. The proposed network can embody a number of analog signal conditioning circuits, processor, and communication capabilities, to meet the industrial needs. We propose two applications of this distributed measurement architecture: the monitoring of power quality in an electrical distribution network and the management of a water distribution system. Experimental results showing the system performance are also included in the paper. 相似文献
14.
Posture and gesture analysis, together with the monitoring of body kinematics, is a field of increasing interest in bioengineering and several connected disciplines. In this paper, some typical features of distributed sensing systems are described, as well as a methodology to read signals from such systems. Theory, simulation, results, and some specific applications are shown. Strain gauges have been used as sensors and have been deposited directly onto textile fibers, demonstrating one way to realize a wearable sensor system. 相似文献
15.
One of three complementary models for optimal operation of multi-quality water supply systems is presented. The other two models are the subject of companion papers. The model, which is known as the Q-C (flow-quality) model, includes mass continuity of water and constituents. However, the hydraulic constraints do not appear explicitly. To prevent infeasibilities or unreasonable hydraulic conditions arising from the lack of hydraulic constraints, limits and a cost are associated with the flow in each pipe. The constraints in the model include dilution conditions which depend on flow direction. These dilution conditions are introduced into the model by an exponential function, resulting in a smooth continuous nonlinear programming problem, which is transformed into an equivalent problem and solved by a modified projected gradient method. The method is insensitive to scaling of variables, and the computational complexity depends only slightly on the number of water quality parameters. The method is demonstrated by application to two examples: the solution for a small network is presented in detail, and main results are shown for a larger one. The results of these two applications indicate the method's applicability to real networks. 相似文献
16.
Flexible glass is a relatively new kind of substrate with a unique combination of properties that are, in different aspects, ideal for numerous applications. The material has aroused significant interest and has prompted activities in R&D communities dedicated to topics such as flexible electronics, flexible OLED and flexible PV. As a result, device demonstrators of considerable maturity have been created, some of which were even manufactured using a roll‐to‐roll (R2R) process. So far, these activities have not resulted in marketable final products that are produced in an industrial context. The key prerequisite for a widespread industrial adoption of R2R processing of flexible glass substrates is the availability of suitable and proven manufacturing equipment. The tools need to be able to handle and process this delicate material, taking into account its mechanical properties, which differ significantly from the typical flexible substrates such as paper, polymer film, or metal foil. This article discusses specific equipment aspects that need to be considered in the R2R handling of flexible glass, both in general and by taking the example of a roll‐to‐roll lab coating system. This tool has been designed specifically for handling flexible glass and will be available to the interested community from October 2016. Furthermore, it is shown how different processes such as R2R sputtering, evaporation, and flash lamp annealing can be used for potential flexible glass applications in flexible electronics, architecture, and energy conversion devices. Beyond that, related layer stacks deposited by vacuum coating will be discussed. 相似文献
17.
《IEEE transactions on instrumentation and measurement》2009,58(9):3086-3093
18.
Giovanni Celano Philippe Castagliola 《Quality and Reliability Engineering International》2020,36(4):1313-1332
We investigate the challenges to be faced by quality practitioners to implement a control chart for individuals aimed at monitoring the stability of maximum/minimum realizations of profile quality features. We consider the situation where only a limited amount of inspections can be scheduled, which is typical of the most recent manufacturing applications for the production of small lots of customized products or processes characterized by frequent changeovers. A quantitative study on simulated profiles described by functional data modelled as random Gaussian fields is provided. Finally, we discuss how the proposed control chart can be implemented in a canning process. 相似文献
19.
Hossein Hazrati‐Marangaloo Rassoul Noorossana 《Quality and Reliability Engineering International》2019,35(6):1753-1765
Dynamic networks require effective methods of monitoring and surveillance in order to respond promptly to unusual disturbances. In many applications, it is of interest to identify anomalous behavior within a dynamic interacting system. Such anomalous interactions are reflected by structural changes in the network representation of the system. In this paper, a dynamic random graph model is proposed that takes into account the past activities of the individuals in the social network and also represents temporal dependency of the network. The model parameters are appearance and disappearance probabilities of an edge which are estimated using a maximum likelihood approach. A generalization of a single path‐dependent likelihood ratio test is employed to detect changes in the parameters of the proposed model. Through monitoring the estimated parameters, one can effectively detect structural changes in a temporal‐dependent network. The proposed model is employed to describe the behavior of a real network, and its parameters are monitored via dependent likelihood ratio test and multivariate exponentially weighted moving average control chart. Results indicate that the proposed dynamic random graph model is a reliable mean to modeling and detecting changes in temporally dependent networks. 相似文献