Vent Blockage Research Articles

Research on the intelligent diagnosis method of the server based on thermal image technology

Balancing the uneven temperature distribution of data centers can reduce cooling energy consumption significantly, as the overheated surface of servers is one of the root causes of the uneven distribution. This paper presents a method for intelligently diagnosing server operating status based on the heat distribution of the server surface. Five types of server operation can be diagnosed: normal status, main fan failure, vice-fan failure, air vent blockage and low-load status. The method involves signal processing and pattern recognition techniques such as thermal image enhancement, region segmentation and image classification. First, thermal images of server outlets in running status are captured as data; second, the images are preprocessed for standardization; third, after homomorphic filtering enhancement, the images are subjected to one-dimensional maximum entropy segmentation to obtain server hotspot images; fourth, morphological features, texture features and statistical features are extracted from hotspot images; finally, the server status is diagnosed by a support vector machine.Experiment results show that the method achieves a diagnosis accuracy of 91.111%. This method can solve the problem of uneven heat distribution in data centers effectively.

English

4 ABSTRACT: Fault diagnosis is an ongoing significant research field due to the constantly increasing need for maintain ability, reliability and safety of industrial plants. The pneumatic actuators are installed in harsh environment: high temperature, pressure, aggressive media and vibration, etc. This influenced the pneumatic actuator predicted life time. The failures in pneumatic actuator cause forces the installation shut down and may also determine the final quality of the product. A fuzzy logic based approach is implemented to detect the external faults such as Actuator vent blockage, Diaphragm leakage and in correct supply pressure. The fuzzy system is able to identify the actuator condition with high accuracy by monitoring five parameters. The parameter selection is based on the committee of DAMADICS (Development and Application of Methods for Actuator Diagnosis in Industrial Control Systems). The Fuzzy Inference Systems were implemented in real time using MATLAB and the results prove that the system can effectively classify all the types of external faults.

Constraints on dacite magma degassing and regime of the June 15, 1991, climactic eruption of Mount Pinatubo (Philippines): New data on melt and crystal inclusions in quartz

To better constrain processes that operated prior to and during the dacite magma eruption of Mount Pinatubo on June 15, 1991, primary inclusions found in quartz phenocrysts of white dacite pumice have been studied by combining micro-analytical techniques with homogenisation experiments. Inclusion morphology and composition before and after homogenisation experiments performed in gas pressure vessels at 760–780 °C and 185–200 MPa distinguish two stages of magma degassing. During the first stage, which occurred prior to eruption, the host quartz trapped a fluid-saturated rhyolitic melt with an average of 78.6±0.7 wt.% SiO 2, 12.4±0.5 wt.% Al 2O 3 and 7±0.3 wt.% H 2O and a water-rich fluid. Microanalyses on the quartz-hosted multiphase and crystal inclusions indicate that the dacite magma crystallised at 750±5 °C, an oxygen fugacity of 1.5–1.7 log f O2 units above the NNO (nickel–nickel oxide) buffer, and a total pressure of 190±50 MPa corresponding to depths from 4 to 7 km. In the second stage, which corresponds to the magma eruption and decompression to 12–23 MPa, volatile exsolution provoked decrepitation of unstable melt inclusions and the loss of initially high H 2O contents from all >80 μm glassy and Hourglass inclusions to 1.7±0.3 wt.% H 2O. The exsolution of ∼5 wt.% H 2O from the dacite magma might have occurred at depths of 300–700 m due to vent blockage caused by the sudden collapse of the conduit walls. These conditions of the climactic eruption in combination with an extreme mass eruption rate reaching 2×10 9 kg s −1 could create oscillations between convecting and collapsing columns, which explains the alternation of pyroclastic-flow deposits with plinian pumice-fall deposits reported in previous studies.

Complex proximal deposition during the Plinian eruptions of 1912 at Novarupta, Alaska

Proximal (<3 km) deposits from episodes II and III of the 60-h-long Novarupta 1912 eruption exhibit a very complex stratigraphy, the result of at least four transport regimes and diverse depositional mechanisms. They contrast with the relatively simple stratigraphy (and inferred emplacement mechanisms) for the previously documented, better known, medial–distal fall deposits and the Valley of Ten Thousand Smokes ignimbrite. The proximal products include alternations and mixtures of both locally and regionally dispersed fall ejecta, and numerous thin complex deposits of pyroclastic density currents (PDCs) with no regional analogs. The locally dispersed component of the fall deposits forms sector-confined wedges of material whose thicknesses halve radially from and concentrically about the vent over distances of 100–300 m (cf. several kilometers for the medial–distal fall deposits). This locally dispersed fall material (and many of the associated PDC deposits) is rich in andesitic and banded pumices and richer in shallow-derived wall-rock lithics in comparison with the coeval medial fall units of almost entirely dacitic composition. There are no marked contrasts in grain size in the near-vent deposits, however, between locally and widely dispersed beds, and all samples of the proximal fall deposits plot as a simple continuation of grain size trends for medial–distal samples. Associated PDC deposits form a spectrum of facies from fines-poor, avalanched beds through thin-bedded, landscape-mantling beds to channelized lobes of pumice-block-rich ignimbrite. The origins of the Novarupta near-vent deposits are considered within a spectrum of four transport regimes: (1) sustained buoyant plume, (2) fountaining with co-current flow, (3) fountaining with counter-current flow, and (4) direct lateral ejection. The Novarupta deposits suggest a model where buoyant, stable, regime-1 plumes characterized most of episodes II and III, but were accompanied by transient and variable partitioning of clasts into the other three regimes. Only one short period of vent blockage and cessation of the Plinian plume occurred, separating episodes II and III, which was followed by a single PDC interpreted as an overpressured "blast" involving direct lateral ejection. In contrast, regimes 2 and 3 were reflected by spasmodic sedimentation from the margins of the jet and perhaps lower plume, which were being strongly affected by short-lived instabilities. These instabilities in turn are inferred to be associated with heterogeneities in the mixture of gas and pyroclasts emerging from the vent. Of the parameters that control explosive eruptive behavior, only such sudden and asymmetrical changes in the particle concentration could operate on time scales sufficiently short to explain the rapid changes in the proximal 1912 products.

Diagnosis of process valve actuator faults using a multilayer neural network

This paper investigates the ability of a multilayer neural network to diagnose actuator faults in a Fisher-Rosemount 667 process control valve. A software package that comes with the valve is used to obtain experimental figures of merit related to the position response of the valve given a step command. The particular values of the dead time, peak time, percent overshoot, steady state error, 63% and 86% rise times, and gain are shown to depend on the severity of three commonly occurring faults: incorrect supply pressure, actuator vent blockage, and diaphragm leakage. The relationships between these parameters form fault signatures for each operating condition that are subsequently learned by a multilayer feedforward neural network. The results show that the trained network has the capability to detect and identify various magnitudes of the faults of interest. In addition, it is observed that the network has the ability to estimate fault levels not seen by the network during training. The approach presented in this paper allows the existing instrumentation to be utilised without modification. Thus, the proposed methodology is practical to implement.

Neural network classifiers applied to condition monitoring of a pneumatic process valve actuator

As modern process plants become more complex, the ability to detect and identify the faulty operation of pneumatic control valves is becoming increasingly important. In this work, a neural network pattern classifier is employed to carry out fault diagnosis and identification upon the actuator of a Fisher–Rosemount 667 industrial process valve. The network is trained with experimental data obtained directly from a software package that comes with the valve. This has eliminated the need for additional instrumentation of the valve. Using this software, tests are carried out to obtain experimental parameters associated with the valve performance for incorrect supply pressure, diaphragm leakage, and vent blockage faults. Specifically, the valve signature and dynamic error band tests are used to directly obtain lower and upper bench sets, minimum, maximum, and average dynamic errors, as well as the dynamic linearity. Additionally, valve deadband and hysteresis are measured graphically from the available valve signature plots for each faulty condition. The relationships between these parameters, for each fault, form signatures that are subsequently learned by a multilayer feedforward network trained by error back-propagation. The test results show that the resulting network has the ability to detect and identify various magnitudes of each fault. It is also observed that a smaller network with a shorter training time results when the valve deadband and hysteresis are included in the training data. Thus, the extra effort required to extract these parameters from the valve signature plots is justified.

A complex Quaternary ignimbrite-forming phonolitic eruption: the Poris Member of the Diego Hernández Formation (Tenerife, Canary Islands)

The Poris Member (0.28 Ma) of the Diego Hernández Formation (Tenerife, Canary Islands) is a widespread succession of plinian fall, surge and non-welded ignimbrite deposits. It was erupted from the northeastern sector of the multicyclic Las Cañadas Caldera, the summit caldera complex of the Las Cañadas Edifice. We present new stratigraphic data which allow the evolution of the eruption to be divided into six main stages: (1) an initial surge-producing phreatomagmatic phase. (2) Generation of a buoyant plinian column culminating in vent-wall collapse and temporary vent blockage. (3) A resumption of phreatomagmatic activity, producing accretionary lapilli-bearing ash surges and a phreatomagmatic ignimbrite. (4) Sustained column collapse, resulting in the progressive aggradation of a complex, compositionally layered ignimbrite sequence. (5) A late plinian phase marked by sharp chemical zonation. (6) Final vent destruction and the generation of multiple surges and pyroclastic flows. Volume calculations indicate a total erupted volume in the order of 13–14 km 3 (3–4 km 3 dense rock equivalent), which together with facies and lithic analysis implies that a small-scale caldera collapse occurred, contributing to the incremental enlargement of the Las Cañadas Caldera. The geochemistry and mingling inter-relationships of four magmatic endmembers, ranging from alkaline mafic to evolved phonolitic liquids, indicate that two magma chambers fed stages 4 and 5 of the eruption sequence. The eruption was triggered when mafic magma intruded the two-chamber system.

Stratigraphy, structure, and volcanic evolution of the Pico Teide–Pico Viejo formation, Tenerife, Canary Islands

The structure and volcanic stratigraphy of the Pico Teide–Pico Viejo (PT–PV) formation, deriving from the basanite–phonolite stratovolcanoes PT and PV, and numerous flank vent systems, are documented in detail based on new field and photogeologic mapping, geomorphologic analysis, borehole data, and petrological and geochemical findings. Results provide insight into the structure and evolution of the PT–PV magma system, and the long-term, cyclic evolution of Tenerife's post-shield volcanic complex. The PT–PV formation comprises products of central volcanism, mainly emplaced into the Las Cañadas caldera (LCC), and contemporaneous products from adjacent rifts. PT–PV central volcanic products become more differentiated up-section with felsic lavas dominating the recent output of the system. This is attributed to the evolution of a shallow magma reservoir beneath PT that was emplaced early in the PT–PV cycle on the intra-caldera segment of Tenerife's post-shield rift system. The rift axis has been the focus of PT–PV intrusive and eruptive activity, and has controlled the location of the stratocones. The current geometry of the rifts reflects a major structural reorganisation defining the start of the PT–PV cycle at ∼0.18Ma, namely the truncation of the north side of the LCC/LCE by the giant Icod landslide. The internal stratigraphy of the PT–PV formation suggests that PT developed early, with PV developing as a satellite vent. Activity has since alternated between PT and PV due to episodes of vent blockage or chamber sealing. These processes have allowed significant volumes of phonolitic magmas to develop and accumulate within the PT chamber, which have vented through radial dike systems during tumescence episodes and from the rift system, which has permitted lateral magma transport. The PT–PV magma system is a potentially hazardous source of future, felsic eruptive activity on Tenerife.

Mouth Insertion Depths in Canadian Smokers

Abstract There is the potential for smokers of ventilated cigarettes to block the ventilation holes either accidentally or deliberately thereby altering the smoke deliveries from those obtained by standardized machine smoking. One way in which the holes can be blocked is by inserting the cigarette into the mouth so that the holes are partially or completely blocked by the lips of the smoker. We have assessed to what extent this occurs amongst Canadian smokers by measuring the saliva patterns on 2756 cigarette butts collected in Montreal, Toronto and Vancouver. The butts were a cross-section of brands smoked in Canada. Saliva stains were visualized by treating the tipping paper with ninhydrin solution. The insertion depth was assumed to be the maximum extent of the saliva stain from the mouth end of the tipping. The brand of each cigarette butt was identified where possible as well as whether the filter was ventilated and if so, the distance of the vent holes from the mouth end. The butt lengths were also determined. Of the 2756 butts collected, 2232 had lip imprint patterns that could be visualized with ninhydrin solution. 56.2 % of the butts with measurable insertion depths, and which could be identified by brand, were ventilated. There was no significant difference between the average insertion depths for ventilated and non-ventilated brands (10.6 AA± 3.6 and 11.0 AA± 3.6 mm respectively). It was estimated that for the ventilated brands between 3.7-10.3 % of the butts could have had the vents blocked completely for at least one puff, 13.8-20.4 % of the butts had vents that could have been partially blocked and 75.9 % of the butts showed no sign of any vent blockage during smoking.

FACTORS AFFECTING RYE (SECALE CEREALE L.) UTILIZATION IN GROWING CHICKS. I. THE INFLUENCE OF RYE LEVEL, ERGOT AND PENICILLIN SUPPLEMENTATION

Five experiments were conducted to evaluate the influence of rye level, ergot and penicillin on the utilization of rye by growing chicks. The effects of the following factors and/or treatments, respectively, were studied: increasing levels of rye replacing wheat in the diets for starting and finishing broiler chicks; ergot, pelleting and penicillin supplementation of rye diets; the cleaning of the beaks or vents of rye-fed chicks; and increasing levels of penicillin in rye diets containing different levels and types of protein supplements for Leghorn chicks. The results indicate that a diet containing 15% rye depressed the appetite and growth of young broiler chicks. Levels of rye higher than 15% in the diet depressed not only growth but also the efficiency of feed utilization in all chicks. The level of ergot in excess of three times that present in the uncleaned rye diet (0.11%) had no influence on chick performance. Wet excreta were produced by rye-fed but not by wheat-fed chicks. There was no relationship, however, between chick performance, and excreta "wetness," beak impaction and vent blockage. An improvement in chick performance was elicited by pelleting or penicillin supplementation of rye diets; the magnitude of the chick response to the latter treatment appeared to be influenced by the type and level of the dietary protein supplement. A dose-response study demonstrated that the maximum effective response to penicillin supplementation occurred when a rye–meat meal diet contained penicillin at or in excess of 160 mg/kg of diet; the corresponding maximum improvements in weight gain and the efficiency of feed utilization were 46 and 18%, respectively.