bluuebunny/crossref_metadata_2025_split huggingface dataset:
North Atlantic Barotropic Vorticity Balances in Numerical Models
Authors: Schoonover Joseph , Dewar William , Wienders Nicolas , Gula Jonathan , McWilliams James C. , Molemaker M. Jeroen , Bates Susan C. , Danabasoglu Gokhan , Yeager Stephen 
Published: November 2015

AbstractNumerical simulations are conducted across model platforms and resolutions with a focus on the North Atlantic. Barotropic vorticity diagnostics confirm that the subtropical gyre is characterized by an inviscid balance primarily between the applied wind stress curl and bottom pressure torque. In an area-integrated budget over the Gulf Stream, the northward return flow is balanced by bottom pressure torque. These integrated budgets are shown to be consistent across model platforms and resolution, suggesting that these balances are robust. Two of the simulations, at 100- and 10-km resolutions, produce a more northerly separating Gulf Stream but obtain the correct integrated vorticity balances. In these simulations, viscous torque is nonnegligible on smaller scales, indicating that the separation is linked to the details of the local dynamics. These results are shown to be consistent with a scale analysis argument that suggests that the biharmonic viscous torque in particular is upsetting the inviscid balance in simulations with a more northerly separation. In addition to providing evidence for locally controlled inviscid separation, these results provide motivation to revisit the formulation of subgrid-scale parameterizations in general circulation models.
Quantitative Measures of Swallowing Deficits in Patients With Parkinson’s Disease
Authors: Ellerston Julia K. , Heller Amanda C. , Houtz Daniel R. , Kendall Katherine A. 
Published: November 2015

Objective: Dysphagia and associated aspiration pneumonia are commonly reported sequelae of Parkinson’s disease (PD). Previous studies of swallowing in patients with PD have described prolonged pharyngeal transit time, delayed onset of pharyngeal transit, cricopharyngeal (CP) achalasia, reduced pharyngeal constriction, and slowed hyolaryngeal elevation. These studies were completed using inconsistent evaluation methodology, reliance on qualitative analysis, and a lack of a large control group, resulting in concerns regarding diagnostic precision. The purpose of this study was to investigate swallowing function in patients with PD using a norm-referenced, quantitative approach. Methods: This retrospective study includes 34 patients with a diagnosis of PD referred to a multidisciplinary voice and swallowing clinic. Modified barium swallow studies were performed using quantitative measures of pharyngeal transit time, hyoid displacement, CP sphincter opening, area of the pharynx at maximal constriction, and timing of laryngeal vestibule closure relative to bolus arrival at the CP sphincter. Results: Reduced pharyngeal constriction was found in 30.4%, and a delay in airway closure relative to arrival of the bolus at the CP sphincter was the most common abnormality, present in 62% of patients. Previously reported findings of prolonged pharyngeal transit, poor hyoid elevation, and CP achalasia were not identified as prominent features.
Attitudes toward Person-Person Communications Media
Authors: Champness Brian G. 
Published: November 2015

Several recent experiments in fields such as bargaining, opinion change, and problem solving have employed the medium of communication as an independent variable. The present study was designed to investigate attitudes toward three media: face-to-face, loudspeaking audio, and closed-circuit television. Thirty-six pairs of managerial civil servants engaged in three 6-min. discussions, one via each medium, in a completely controlled design. After each discussion, subjects completed a 24-scale, semantic differential, media-attitude questionnaire. There were significant effects of the media upon 20 of the 24 scales. The scale scores were factor analyzed using both orthogonal and oblique rotation of five factors. There were significant effects of the media upon scores from three of the factors (Aestheticism, Evaluation, and Privacy). The differences found have implications both for previous explanations of the effects of media on laboratory task performance, and for the real-life use of person-person communications systems.
Field Mach-Zehnder Interferometer for Heat-Transfer Studies
Authors: Brooks R. G. , Probert S. D. , Maxwell J. 
Published: November 2015

The use of interferometry for heat transfer studies enables a complete field of view to be quantitatively examined at one time without disturbing the temperature distribution being measured. The Mach-Zehnder interferometer described has an elliptical field, with a 15cm minor axis and is capable of accommodating test chambers 102cm in length using the full field of view. The sensitivity of the instrument for various air pressures and temperature distributions within the test cell has been evaluated. The use of the instrument for identifying isotherms in the neighbourhood of a heated slab supported on skid bars is described. A Moiré technique which eliminates the effects of imperfections in the interferometer plates has also been used.
An Automatic Optimiser for Air Flow Direction Measurement
Authors: Porter A. M. , Neely P. L. , Bond A. D. 
Published: November 2015

A self-adaptive instrument servomechanism has been devised to enable airflow direction to be automatically determined when using a hot wire anemometer for flow measurements. In the anemometer, used for measuring air velocity and turbulence, a fine wire acts as the sensing element. The wire is maintained at constant temperature by an automatically balancing bridge circuit, the voltage across which is a measure of the rate at which the flow is cooling the wire. When the probe from such an instrument is rotated through 360° in an air stream the voltage/angle characteristic is as shown in Fig. 1; with the wire axis along the flow direction the bridge voltage is a well-defined minimum while a less definite maximum voltage is obtained with the wire normal to the flow. Location of the successive minima or maxima is achieved by a hill-climbing method. The device has been developed for taking measurements in two dimensional flow within the rotors of certain fans where difficulties of access preclude the use of any probe having a large head.
In-Line Control and Optimisation on Solvent Extraction Processes
Authors: Mills A. L. 
Published: November 2015

The performance of a solvent extraction plant both with respect to throughput and product purity can be improved by operating the plant in such a manner as to leave no chemically uncombined solvent in the process. The feedstocks of most solvent extraction plants are of a fairly constant composition for relatively long periods of time, thus optimisation of flowsheets and operating conditions can be carried out off line and simple conventional controllers can be used for plant control.
Safety Assessment—A Method for Determining the Performance of Alarm and Shutdown Systems for Chemical Plants
Authors: Hensley G. 
Published: November 2015

Safeguards, for costly and hazardous chemical plants, are often provided by means of alarm or automatic shutdown systems. The adequacy of this protection—which is a measure of the capability of the newly installed system in shutting down the plant on the occurrence of a hazardous condition, and its effectiveness over the long term (its reliability)—may be judged by an independent safety assessment. Both qualitative and quantitative aspects of safety analysis are involved in an assessment, the quantitative approach being of particular use where there is a need to compare the anticipated reliability of the proposed system with a numerically specified, reliability requirement. Some of the techniques used in the assessment procedure are discussed in the paper and, by way of example, the performance of a typical shutdown system is assessed and its adequacy judged against a hypothetical plant fault condition.
Equipment for Quantitative Assessment of Control System Performance Using Pseudo-Random Binary Signals
Authors: Beck M. S. , Dadachanji F. M. 
Published: November 2015

The reasons for requiring an accurate prediction of control system performance under actual operating conditions are discussed. It is shown that a measure of the integral square error in response to a stationary time series disturbance meets most requirements. The analytical approach to calculating integral square error is described and a specific example is given. Apparatus for generating the disturbance signal and measuring the integral square error is described. It is suitable for use with systems having a dominant time constant between one second and several hours. Experimental results for a pressure control system are compared with the theoretically predicted results. The disturbance generator can also be used for generating pseudo-random binary sequences.
Moisture Measuring Systems Critically Reviewed
Authors: von Tolkacz Martin 
Published: November 2015

Until recently, mainly two methods to determine the moisture content of running fibre webs were recognised and in practical use: the measurement of the conductivity of the web and the measurement of the dielectric constant or dielectric losses. For some time paper makers have been able to choose between these and a third method, the so-called infrared system. This is an attempt to compare the measuring characteristics of these three methods and to consider carefully the costs and the results obtained. Let us list first of all the requirements a continuous moisture meter has to meet on a paper-making machine. In addition, the function of the three types of gauges will be briefly explained.
Transfer Functions from Sampled Impulse Responses
Authors: Zaman M. , Griffin A. W. J. 
Published: November 2015

A mathematical formulation is developed for obtaining the frequency responses from known sampled impulse responses of linear dynamical systems. This is done by assuming a straight line approximation from one sampled point to the next and performing the usual Fourier Transformation for this interval. This is repeated for all sampled points and the results are summed together. In practice sampled impulse responses can be obtained using correlation techniques. The frequency responses as obtained above are then processed by a generalised method, developed by the authors, to determine the transfer functions. The unique feature of this method is that the transfer functions can be obtained from the frequency responses without any idea about the actual order of the system and its poles and zeroes. However, the actual principle employed, that of complex curve fitting, is already a well established technique. Finally, many examples are presented which show the validity of the methods where impulse responses are exact and also corrupted by errors. The treatment is restricted to systems which have a finite dc gain. The numerical calculations are processed on an ICT 1905 computer.
A Review of the Work of J. L. Hodgson on the Measurement of Pulsating Flow
Authors: Zanker K. J. 
Published: November 2015

Both the published and unpublished work of Hodgson on the measurement of pulsating flow rates by means of pressure differential devices is dealt with. Such situations are governed by the Hodgson number H0 = (CF/q) (L/p). The derivations, significance and practical application of the Hodgson number are discussed. Also considered briefly are other types of flow meters developed by Hodgson that were less affected by pulsating flows.
Radioisotope Techniques for Measurement and Control of Industrial Pollution
Authors: Cameron J. F. 
Published: November 2015

Radioisotope techniques used for measurement and control of industrial pollution include radioisotope instruments and tracers, activation analysis, and radiation treatment of waste water and processing of chemicals. Radioisotope instruments monitor and control potential sources of pollution such as sulphur in hydrocarbons or ash in coal and papers, measure the concentration of pollutants in air and water, and assist in the control of sewage treatment plants. Activation analysis provides a sensitive, specific and versatile method for elemental analyses of pollutants in air, water, plants and animals, while radioisotope tracer techniques permit the study of the movement of liquid effluents and atmospheric pollutants, and trace the origins of oil spillages. Radiation treatment of waste water is feasible but uneconomic at present, and radiation processing can produce chemicals useful in combating pollution.
Pseudo-Random Pressure Pulses Used to Determine the Shape of Reflected Waves from an Opening
Authors: Reed E. W. , Ali M. A. , Gill K. F. 
Published: November 2015

This work forms part of a study into reflection behaviour within a duct directed towards the understanding of the problems associated with metering pulsating gas flows. A novel application of correlation analysis is used to predict the shape of the reflected wave from an opening of finite thickness. The incident wave is in the form of a pseudo-random binary sequence pressure pulse sequence which enables incident and reflected waves to be distinguished one from the other. It is shown that for waves of small amplitude, reflections do not occur in like shape to that of the incident wave. These shapes are influenced by both the amplitude of the incident wave and the geometry of the opening. It is believed that this technique makes an original contribution to the study of reflection behaviour and the use of correlation analysis.
Control Valve Movement Limitations — An Essay in Practical Control Engineering
Authors: Martin E. N. 
Published: November 2015

All control systems are subject to constraints on both the magnitude of the corrections and the rate at which they can be applied to a process, and violation of these constraints, in response to severe disturbances, then leads to a deterioration in control performance just when it is most unwelcome. An attempt is therefore made to explain these effects in simple terms, and it is shown that a change in controller configuration could provide a complete solution. Because this cannot be generally applied, however, the use of a design criterion taking account of the rate constraint, and of high speed valve actuators as a means of economising in capital cost, are discussed with examples.
Computer Aided Dynamical System Analysis and Control for Undergraduate Courses
Authors: McCorkell C. , Wilson N. 
Published: November 2015

Dynamical system analysis is included in undergraduate courses in the Northern Ireland Polytechnic, as part of a presentation of general engineering methodology and more particularly, accompanied by synthesis techniques, in control options at final year honours level. Such is the extent of the computational requirement, necessary for a non-trivial treatment, that steps have been taken to introduce computer usage where possible. Included is information on the initial stage of a project undertaken to provide for the computational needs of undergraduates involved in dynamical problems in the laboratory.
Reliability of Large Systems
Authors: Hunns D. M. 
Published: November 2015

Modern plants and processes can involve the accumulation of unnatural concentrations of hostile substances in high energy situations. The safe storage of the ingredients and products of these processes, the controlled disposal of waste and the successful harnessing of the reaction energies are all problems which tax our technological resources. There is now sufficient evidence from recent years to demonstrate the potential of fault situations to cause vast economic losses in terms of plant damage and loss of production, to cause loss of life and injury to numbers of operators and in some cases to cause the effects of the catastrophe to extend far beyond the bounds of the factory fence. The need to objectively measure and regulate reliability has now long since been clear and has stimulated the growth of a formalised methodology of reliability assessment which finds expression in quantitative terms. This quantitative component of assessment offers an analogue scale of performance estimation. By this means alternative design strategies can be decisively compared and the reliability spectrum of the component-sections (at any chosen hierarchical level) of a system can be derived. Also the reliability performance of a system may be assessed with respect to some quoted target criterion. Such a target criterion may be derived in reference to plant economics, plant safety or both. Thus a definitive means of gauging the adequacy of the reliability of systems is provided which is increasingly of value as the scales of our technological activities grow. The ability to regulate the reliability of plant to satisfy explicitly derived performance requirements clearly places a valuable and reassuring tool in the hands of the designer. Not only does the tool enable the correct level of reliability to be designed into a system (which is itself cost effective) but also provides a sufficient break-down of performance constituents to enable the most cost effective means of achieving this level to be found.
A Silt-Salinity-Depth Profiling Instrument
Authors: Shepherd I. E. 
Published: November 2015

The planning of new port facilities in muddy estuaries often calls for the acquisition of velocity, salinity and suspended solids data throughout the length of the estuary at several stages of the tidal cycle. The tidal regime in most estuaries causes periodic scour, transport in suspension, and deposition of fine grained sediments. Interaction of the tidal and fluvial flows may generate a pattern of saline stratification and longitudinal density currents which are important in determining the zones of maximum siltation in the navigation channel. Each estuary has a unique tidal current-salinity-sediment transport regime. It is a major exercise to organise the simultaneous measurement of these variables from a series of stationary barges or boats, especially if the salinity and sediment transport patterns depend on the occurrence of particular combinations of tides and fluvial flows. Because the measurement of salinity and suspended solids by conventional sampling techniques is a slow process, a profiling instrument has been developed at the Hydraulics Research Station, which permits measurements to be made rapidly from a high speed launch at several sites during substantially identical tidal states. This paper describes the design of the transducers used for salinity and suspended solids measurements, and how they have been incorporated into a simple low cost system for rapid indications of the results.
Hygrometry
Authors: Riemer W. , Röss R. 
Published: November 2015

To meet the many different requirements of gas humidity and water vapour measurement, a wide variety of measurement techniques has been developed. The criteria for deciding which technique to use are the range of concentration, the accuracy of measurement required, the sensitivity, and the pressure or even the corrosiveness of the gas sample. For measuring traces of moisture, sensors are used in which the admittance of an arrangement of electrodes changes with the partial pressure of the water vapour. Another method measures desorption due to Joule heat after absorption of the water by phosphorus pentoxide. Devices for measuring high humidities are equipped with capacitive, temperature-controlled sensing elements which measure the dew point. For special application, units have been developed which make use of the dielectric absorption of microwaves by the water. For hygrometrical problems requiring a high degree of accuracy, good discrimination and continuous measurement, a method is discussed below which uses the absorption of IR radiation by molecules in gaseous phase: Non-Dispersive Infra-Red Analysis.
Measurement and Control Problems of a Multinational Pharmaceutical Manufacturer
Authors: Smith Ray 
Published: November 2015

Although making specific reference to pharmaceutical production the problems and principles described apply to a wide variety of industries, and may therefore be of general interest. In the spirit of technology transfer the paper is deliberately written in ‘mid-Atlantic’ English. The author is a specialist engineer within the Project Unit of a major UK-based pharmaceutical company, which operates a broadly decentralised management structure. The views expressed are his own and do not necessarily represent those of the company.
The Durham MEng Degree Course — An Innovation in Postgraduate Education
Authors: Holgate M J 
Published: November 2015

MEng Courses — A clarification for readers of the following article: The Engineering Council defines MEng Degree courses in its Sartor document as follows: ‘It is Council policy that degree courses in engineering accredited in relation to stage 1 of the Chartered Engineer Section of the register should be designated as Bachelor of Engineering (BEng) or if appropriately extended as Master of Engineering (MEng). The Council disapproves of and will strongly discourage, the use of these titles for other courses.’ The Engineering Council further defines MEng as ‘an extended course’ and recommends that selection to an ‘extended’ degree course should include assessment during the first two years of an accredited ‘enhanced’ degree course and performance at an interview. The Durham MEng Course (as well as some other similar courses at various Universities) is a very good course but is essentially a one year postgraduate Course and therefore runs counter in concept to the stated policy of the Engineering Council. This explanation is given to avoid any confusion which may be engendered in the mind of the reader.
The Application of On-Line Expert Systems to Supervisory Process Control
Authors: Foster Howard M , Meadowcroft Simon R 
Published: November 2015

The use of computers in the process industry is set to increase. However, the implementation of conventional computer technology is not adequate for executing the complex supervisory tasks. This paper speculates upon the use of on-line expert systems which have been developed for working in non-linear, non-algorithmic problem domains. Expert systems for supervisory control are explored, and the potential benefits for optimisation and improved accuracy of control are outlined. The complexity and multi-tasking nature of real-time supervisory control points to an expert system structure which is distributed. A modular expert system design is proposed and the potential benefits for the approach are evaluated.
The Single European Act — 1992: Implications for Measurement and Control
Authors: Cornish Derek 
Published: November 2015

The 31 December 1992 completion of the internal market as envisaged in the Single European Act will have far-reaching consequences for all Europe, as member-states, companies, employers, employees and as individuals. Not all the consequences can be foreseen, but progress is being achieved at an ever faster pace. The estimated economic gains of £140 billion or more and the creation of millions of new jobs are powerful incentives! What will be the impact on instrumentation, measurement and control? This introductory article by the President is the first of a series to be published in Measurement and Control, each being written from a different viewpoint. They will address the issues involved and seek to highlight the evolving situations.