Proposal to Raise the Student Activity Fee 1978

This document is a proposal to raise the student activity fee. The report makes five arguments for raising the fee: 1) Increase in number of student groups to fund, 2) Decrease in the student enrollment, 3) Inflation, 4) Increase in programming, and 5) Increase in scholarship amount. Additionally, the proposal includes the Campus Council Approved Budget for the 1977-1978 fiscal year.https://openworks.wooster.edu/campuscouncil/1055/thumbnail.jp

MODEL-BASED FAULT DETECTION AND DIAGNOSIS FOR ELECTROMAGNETIC VALVE DRIVES

ABSTRACT This paper describes the model-based fault detection and diagnosis for electromagnetic actuators. Due to hysteresis behavior, the model of Jiles and Atherton is INTRODUCTION Electromagnetic actuators increasingly replace the traditional, purely mechanically, pneumatically, or hydraulically driven actuators. In the area of electro-hydraulic servo axes, directly driven proportional valves replace in many applications the two-stage valves with the traditional nozzle-flapper construction controlled by torque-motors. Wear and tear due to abrasion, erosion, and excessive temperature can severely degrade the operating time. Furthermore, the ongoing integration of electromagnetic actuators in mechatronic systems, puts even more emphasis on the need to detect and diagnose faults autonomously. Signalbased methods such as limit checking or trend checking, which so far have mostly been applied in industry, do not allow the detection of tiny, incipient faults. Typically, the fault becomes large without being detected and therefore, the plant must immediately be shut down when the fault is detected by classical methods. Using modern, process-model based methods, it is however possible to detect and diagnose faults in a much earlier stage and thus prevent the shutdown of the plant by means of fault-management methods, such as reconfiguration of the control, switching-over from a defect to an intact component. The paper will present the design of such a model-based fault detection and diagnosis system for electromagnetic drives

Active fault tolerant control of an electro-hydraulic servo axis with a duplex-valve-system

In this paper fault detection, fault diagnosis and active fault tolerant control of an electro-hydraulic servo-axis with a duplex-valve-system are described. The fault detection is based on parity equations. The semi-physical models allow the detection of even small faults in the hydraulic system. The fault diagnosis used on the testbed is based on fuzzy-logic. In order to tolerate a failed hydraulic proportional valve, a duplex-valve-system built up with standard direct-driven proportional valves is applied. The fault management module allows the supervision of the hydraulic servo axis and decides on reconfiguration and fault accomodation of the control-loop. The Internal Model Control (IMC)-tracking control structure used for reconfiguration allows bumpless transfer between controllers. Experimental results show the industrial applicability of the approach

Fault-tolerant control of an electro-hydraulic servo axes with a duplex-valve-system

This paper presents fault detection, fault diagnosis, the fault-tolerant control of an electro-hydraulic servo axes with a duplex-valve-system. The fault detection is based on parity equations and is load independent. The semi-physical models allow the detection of even small faults in the hydraulic system. The fault diagnosis used at the testbed is based on fuzzy-logic. In order to tolerate a faulty hydraulic proportional valve, a duplex-valve-system built up with standard proportional valves is applied. The fault management module allows the supervision of the hydraulic servo axes and decides on the reconfiguration of the control-loop. An Internal Model Control (IMC)-tracking control structure for bumpless transfer between controllers is presented. Experimental results show the industrial applicability of the approach

Revisited Upper Reference Limits for Highly Sensitive Cardiac Troponin T in Relation to Age, Sex, and Renal Function

(1) Background: Highly sensitive cardiac troponin T (hs-cTnT) plays an essential role in the diagnosis of myocardial injury. The upper reference limit of the respective assay is generally applied, irrespective of age, renal function, or sex. We aimed to identify age-adjusted and sex-adjusted upper reference limits in relation to renal function in a large population-based cohort without cardiac diseases. (2) Methods: We included 5428 subjects of the population-based LIFE-Adult cohort, free of diagnosed cardiac diseases. Sex-adjusted and age-adjusted 99th percentiles for hs-cTnT in subjects with preserved renal function were obtained. (3) Results: The hs-cTnT values were higher in men of all age groups. In both sexes, an increasing age positively correlated with higher hs-cTnT values. Hs-cTnT weakly correlated with serum creatinine. The three-dimensional analysis of age, creatinine, and hs-cTnT showed no relevant additional effect of creatinine on hs-cTnT. In men aged above 60 and women above 70, the calculated 99th percentiles clearly exceeded the commonly applied thresholds. (4) Conclusion: Age and sex have a major impact on the serum concentration of hs-cTnT, while renal function does not. We propose to consider age-adjusted and sex-adjusted reference values

Fault diagnosis for uncertain networked systems

Fault diagnosis has been at the forefront of technological developments for several decades. Recent advances in many engineering fields have led to the networked interconnection of various systems. The increased complexity of modern systems leads to a larger number of sources of uncertainty which must be taken into consideration and addressed properly in the design of monitoring and fault diagnosis architectures. This chapter reviews a model-based distributed fault diagnosis approach for uncertain nonlinear large-scale networked systems to specifically address: (a) the presence of measurement noise by devising a filtering scheme for dampening the effect of noise; (b) the modeling of uncertainty by developing an adaptive learning scheme; (c) the uncertainty issues emerging when considering networked systems such as the presence of delays and packet dropouts in the communication networks. The proposed architecture considers in an integrated way the various components of complex distributed systems such as the physical environment, the sensor level, the fault diagnosers, and the communication networks. Finally, some actions taken after the detection of a fault, such as the identification of the fault location and its magnitude or the learning of the fault function, are illustrated