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151.
Summary The output voltage of a detector circuit containing a gas-filled tube sensitive to ultraviolet radiation can be used to indicate whether a flame is still burning or not. As long as the flame is burning the random nature of the discharges of the tube leads to random fluctuations in the output voltage, which can be considered as a Markov-process with dependent increments. The problem is to select an alarm level for the output voltage with a suitable chosen probability of exceedance while the flame is burning, in order to limit the probability of false alarm. In this article a method is given for determining upper and lower bounds for the distribution function of the output voltage at any moment, answering the question of the alarm level to be chosen. Results are given for a special circuit. 相似文献
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Summary Controlling is intervening in a situation on the basis of measurements. The three elements occurring in this definition may each contain an uncertainty that sets a limit to the control efficiency:
The measurements may be in error owing to both inaccuracies and sluggishness of the measurements. Proper and rapid data-processing is essential therefore.
The interventions may lose part of their effect through over-determinancy or dynamically unfavourable (sluggish) responses. In either case statistical calculations disclose the average control errors that are liable to be made, and also the way in which these can be minimized.
The situation may be unclear, i.e. the static and dynamic process characteristics are insufficiently known. In such cases regression and correlation techniques may aid in finding a solution.
Following a general review, we shall discuss in more detail those aspects that are bound up with the dynamics of the phenomena. Arguments from information theory reveal that the dynamic efficiency of control actions depends on correlation functions of time series (disturbances) and response curves of the systems (processes). The effects of disturbance correlation time, disturbance variance, sampling time, sample treatment, measuring errors, measuring time, rapidity of the intervention, etc., on the efficiency are elucidated by means of some formulae, graphs and examples. 相似文献
The measurements may be in error owing to both inaccuracies and sluggishness of the measurements. Proper and rapid data-processing is essential therefore.
The interventions may lose part of their effect through over-determinancy or dynamically unfavourable (sluggish) responses. In either case statistical calculations disclose the average control errors that are liable to be made, and also the way in which these can be minimized.
The situation may be unclear, i.e. the static and dynamic process characteristics are insufficiently known. In such cases regression and correlation techniques may aid in finding a solution.
Following a general review, we shall discuss in more detail those aspects that are bound up with the dynamics of the phenomena. Arguments from information theory reveal that the dynamic efficiency of control actions depends on correlation functions of time series (disturbances) and response curves of the systems (processes). The effects of disturbance correlation time, disturbance variance, sampling time, sample treatment, measuring errors, measuring time, rapidity of the intervention, etc., on the efficiency are elucidated by means of some formulae, graphs and examples. 相似文献
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156.
CASEY DOUGAL JOSEPH ENGELBERG CHRISTOPHER A. PARSONS EDWARD D. VAN WESEP 《The Journal of Finance》2015,70(3):1039-1080
This paper documents that the path of credit spreads since a firm's last loan influences the level at which it can currently borrow. If spreads have moved in the firm's favor (i.e., declined), it is charged a higher interest rate than is justified by current fundamentals, whereas if spreads have moved to the firm's detriment, it is charged a lower rate. We evaluate several possible explanations for this finding, and conclude that anchoring to past deal terms is most plausible. 相似文献
157.
FRANS W. A. VAN POPPEL HENDRIK P. VAN DALEN EVELIEN WALHOUT 《The Economic history review》2009,62(1):99-127
The emergence of the housewife in the Netherlands over the period 1812–1922 was strongly influenced by the social norm that women should withdraw from the labour market on the eve of marriage. Adherence to this norm is most clearly reflected in the emergence of the housewife among the lower classes, especially at the close of the nineteenth century among wives of farmers. Women in urban municipalities, however, set the norm far earlier and differences across social classes were significantly greater in towns than in rural areas. Paradoxically, the rise of the housewife did not change work pressures for lower‐class women. 相似文献
158.
The paper deals with the concept of identification in inferential statistics. At first a general concept of identification is defined and developed. Thereafter, the general theory is applied to univariate linear regression and simultaneous equation systems. Finally, attention is paid to models with lagged variables and some new related problems are suggested. 相似文献
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