Developed Monitoring Method Research Articles

Design of Early Warning Monitoring Systems for Source Waters

Surface water systems may be vulnerable to sudden changes in source water quality as a result of accidental, intentional, or natural contamination from a variety of sources, including spills and storms. Utilities must respond quickly to these events in order to determine appropriate changes in treatment strategy and protect consumers from potentially harmful contaminants. Early warning monitoring systems can facilitate rapid response by using detection, event characterization, and communication to gather the information necessary to make sound decisions. This article discusses the characteristics, components, and design of early warning systems as well as existing and developing monitoring methods and still‐needed research. Case studies provide snapshots of advanced early warning monitoring systems from around the world, in particular Europe and Asia. With a few notable exceptions, US experience with advanced early warning monitoring systems is limited, and most water supplies have little or no early warning system in place. When a contamination event occurs, time is of the essence to protect supplies and safeguard consumer health. Early warning monitoring not only cuts response time but also provides a cost‐effective mechanism for reducing risks, boosting public confidence in the water utility, and promoting good practice and careful reporting on the part of dischargers. Using the information and framework provided here, utilities can begin developing their own early warning monitoring systems, thus ensuring that when water quality is endangered, they won't be caught flatfooted.

On-line monitoring the incore power distribution by using excore ion-chambers

For most of nowaday pressurized water reactors (PWR), excore ion-chambers (EIC) are the sole real-time sensors responding to the incore power distribution (IPD). Conventionally, it is supposed that the EIC could not carry out information of the IPD in radial direction. As a result, there is an excess conservatism when they are being used for the core monitoring so far, and some flexibilities of the reactor operation are sacrificed. Though progresses have been made, there are still some inevitable obstacles about newly developed monitoring methods: mounting and maintaining a large amount of fixed incore detectors are costly; and the IPD calculated by on-line simulators is not the “measured” one. Fortunately variations in the IPD must be driven by reasonable physical causes, and the corresponding variations in the readings of the EIC are notable enough to be identified. So with a specific referenced IPD measured from periodical flux mappings, it is possible to on-line monitor such variations by using the EIC. Aimed at this, a harmonics grouping method and an algorithm of higher order perturbation variables are developed, and an influence equation for control rods is also proposed. Then a precise restriction equation describing the reasonable variations in the IPD is deduced for example of the Heating Reactor. Combined with a proper-configured EIC, a systematic “excore-to-incore” method is realized finally.

Pheromones control oriental fruit moth and peach twig borer in cling peaches

Slow-release pheromone technology can successfully control oriental fruit moth and peach twig borer while eliminating in-season insecticide sprays in cling peaches. In conjunction with a demonstration program, we compared mating disruption for these two pests with standard grower pest-control methods in the Sacramento and San Joaquin valleys, and monitored for pest damage, yield and grower costs. While the mating-disruption program was effective in controlling the targeted pests, costs were higher and growers preferred a partial disruption program that included some supplemental late-season insecticide sprays. Subsequently, we developed monitoring methods to determine the need for supplemental sprays. This partial matingdisruption program still costs about $60 more per acre than a standard spray program. Predicting efficacy and determining the need for supplement sprays is also more difficult with the partial program than with the pheromone-based control program.

Monitoring of flexible production systems using high-level Petri net specifications

The degree of reliability in the operation of flexible production systems depends not only on the operation of the individual components, but also on the structure and evolution of the embedded supervisory control system. Monitoring of operations and of the behaviour of the components and of the system as a whole is an essential function of such a supervisory control system. This paper focuses on the development and implementation of feature- and model-based monitoring methods using high-level Petri net specifications of flexible production systems and of the embedded discrete-event controllers. The combination of machine–human interface concepts with the developed monitoring methods leads to a user-friendly representation of monitoring information. An application at industrial level is shown by means of a case study, i.e., a sample flexible assembly cell, situated at the Institute for Manufacturing Automation and Production Systems, Germany.

SCOLIOSIS SURGERY: APPROPRIATE MONITORING

Correction of scoliosis is largely an elective cosmetic procedure in the young population, who account for the largest portion of the surgical population. Associated with the correction, however, is a very real possibility of major neurological injury, including paralysis. Although the incidence of spinal cord injury was estimated as 0.5% in 1979, 75 newer instrumentation methods have markedly increased the risk. More recent reviews have reported markedly higher figures (e.g., 17% neurologic complications with 4% paralysis 29,40,84 ). The risks are highest for patients with kyphosis, congenital scoliosis, preexisting neurological impairment, and patients in traction preoperatively. As such, there has been a major impetus to develop monitoring methods that could warn the surgeon of impending spinal damage so that the procedure could be altered to improve outcome. Electrophysiologic techniques have been developed to meet this need, and scoliosis surgery serves as an excellent model to evaluate the application of these techniques. This article reviews these techniques and the results of their application to scoliosis surgery.