Gauge Readings Research Articles

Behaviour of hollow circular section with multiple perforations under compression, flexure and torsion

Abstract Effect of the presence of perforations on thin structure has been extensively investigated for decades. Various perforation parameters were investigated in past studies. However, study on thin cylinder with multiple perforations has not been carried out. In searching for lighter structural members, the concept of perforated hollow section has been inspired by the shape and arrangement of multiple perforations observed in the Cholla skeleton. Effects of multiple perforation parameters on circular hollow section have been the main interest. This paper presents the verification of FEM simulation with test results. A non-perforated circular hollow section (control model) and a circular hollow section penetrated with 12 nos. of circular shape perforations in array arrangement were selected for the verification process. Both test specimen and FEA models were subjected to compression, flexural and torsional loads. For result comparison within the material linear range, FEA models show good agreement with test results for compression and flexural load cases, and for control models under torsional load case. For perforated models under torsional load, FEA results correspond well with the inclined strain gauge readings. FEM analysis method is considered capable to produce reliable result for loading within the material linear range for circular hollow sections with multiple perforations.

Experimental Investigation Dowel Action of Longitudinal Reinforcement of Reinforced Concrete Beams

The technique and results of experimental investigation on test samples of shear force magnitude (dowel action) in longitudinal tensile reinforcement in the zone of transverse bending of reinforced concrete beams after the formation of inclined cracks are presented in the article. The design of test samples, the technique of measurement of deformations at carrying out tests is described. Deformations along the length of reinforcing bar were determined by means of chains of strain gauges pasted on the upper and lower faces of the reinforcing bar. According to the results of the study, the distribution of deformations along the length of reinforcing bars in the zone of transverse bending at different stages of loading is established. The experimental values of bending moments and shear forces in reinforcing bars after the formation of an inclined crack and in the failure stage were determined according to the readings of strain gauges. An analysis of the experimental data is performed and a comparison is made between the experimental values of the dowel action of the longitudinal reinforcement of reinforced concrete beams at the intersection of an inclined crack, depending on the percentage of longitudinal reinforcement of section.

Fiber Optic Sensing for Geomechanical Monitoring: (1)-Distributed Strain Measurements of Two Sandstones under Hydrostatic Confining and Pore Pressure Conditions

In this study distributed optic fiber has been used to measure both the Rayleigh and Brillouin frequency shift of two different sandstone core samples under controlled hydrostatic confining and pore pressure in the laboratory. The Berea sandstone core is relatively homogeneous, whereas the Tako sandstone core is visibly heterogeneous with a coarse-grain and a fine-grain region. Rayleigh frequency has been found to have a superior performance over Brillouin frequency in terms of better consistency (less scattering) in the tests carried out. The strain gauge readings reveal considerable anisotropy in the stiffness of the Berea core between perpendicular (vertical) and parallel to the bedding (hoop) directions. The strains converted from Rayleigh frequency shift measurements agree reasonably well with readings by one of the four hoop strain gauge channels under increasing confining/pore pressure. For the Tako sandstone core, the contrast in the grain-size, and thus rock elastic properties, is clearly reflected in the hoop strain measurement by both strain gauges and distributed optic fiber. The outcomes of the test have demonstrated successfully the use of a single optic fiber for measuring rock strain response at different regions of a heterogeneous core sample along a continuous trajectory.

Reconstructing Flood Inundation Probability by Enhancing Near Real-Time Imagery With Real-Time Gauges and Tweets

Flood inundation probability is critical for situation awareness, flood mitigation, emergency response, and postevent damage assessment. Current flood inundation mapping approaches can be categorized into real-time (RT) and near-RT (NRT) processes based on the timing of data acquisition. However, the intrinsic limitations of each category largely hamper their applications for flood mapping. Taking the 2015 South Carolina flood in downtown Columbia as a case study, this paper proposes a flood inundation reconstruction model by enhancing the NRT normalized difference water index (NDWI) derived from remote sensing imagery with the RT data including stream gauge readings and social media (tweets). Splitting into three modules: water height module, global enhancement module, and local enhancement module, the proposed model first incorporates the gauge readings and the NDWI image to reconstruct a macroscale flood probability layer, which is then locally enhanced using the verified flood-related tweets. The final output of the model matches well with the U.S. Geological Survey inundation map and its surveyed high-water marks. Results suggest that by enhancing NRT imagery with RT data sources, the proposed flood inundation probability reconstruction model renders a more robust, spatially enhanced flood probability index for emergency responders to quickly identify areas in need of urgent attention.

Efficiency of image correlation photogrammetry technique in measuring strain

ABSTRACT Strain is one of the basic engineering properties by which materials can be defined, the elastic modulus of any material being derived from the stress-strain curve for a specific material. Strain measurements are also used in examining the efficiency of some structural components, such as composite members, for which the strain indicates the slippage level. A common method of measuring strain is by attaching strain gauges at the locations at which it is necessary to capture the strain, but the disadvantage of this method is that it is not efficient for large-scale elements. The image correlation photogrammetry technique eliminates the need to attach strain gauges on large structural members, and high-speed cameras are used to capture the movements of artificial dots on the structures. However, this method becomes inefficient for large-scale members, is that the manufacturer’s specifications for the technique limit the use of random manual dotting, which makes it time-consuming. A new method of dotting is proposed in this study which involves randomly spraying the structural element to create small dots. The proposed method is compared with the strain gauge readings, the results show the efficiency of the proposed method and can be recommended for researchers and engineers.

Assessment of Satellite and Radar Quantitative Precipitation Estimates for Real Time Monitoring of Meteorological Extremes Over the Southeast of the Iberian Peninsula

Quantitative Precipitation Estimates (QPEs) obtained from remote sensing or ground-based radars could complement or even be an alternative to rain gauge readings. However, to be used in operational applications, a validation process has to be carried out, usually by comparing their estimates with those of a rain gauges network. In this paper, the accuracy of three QPEs are evaluated for three extreme precipitation events in the last decade in the southeast of the Iberian Peninsula. The first QPE is PERSIANN-CCS (Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks - Cloud Classification System) , a satellite-based QPE. The second and the third are QPEs from a meteorological radar with Doppler capabilities that works in the C band. Pixel-to-point comparisons are made between the values offered by the QPEs and those obtained by two networks of rain gauges. The results obtained indicate that all the QPEs were well below the rain gauge values in extreme rainfall time slots. There seems to be a weak linear association between the value of the discrepancies and the precipitation value of the QPEs. The main conclusion, assuming the information from the rain gauges as ground truth, is that neither PERSIANN-CCS nor radar, without empirical calibration, are acceptable QPEs for the real-time monitoring of meteorological extremes in the southeast of the Iberian Peninsula.

Experimental investigation of the strength and failure behavior of layered sandstone under uniaxial compression and Brazilian testing

As a typical inherently anisotropic rock, layered sandstones can differ from each other in several aspects, including grain size, type of material, type of cementation, and degree of compaction. An experimental study is essential to obtain and convictive evidence to characterize the mechanical behavior of such rock. In this paper, the mechanical behavior of a layered sandstone from Xuzhou, China, is investigated under uniaxial compression and Brazilian test conditions. The loading tests are conducted on 7 sets of bedding inclinations, which are defined as the angle between the bedding plane and horizontal direction. The uniaxial compression strength (UCS) and elastic modulus values show an undulatory variation when the bedding inclination increases. The overall trend of the UCS and elastic modulus values with bedding inclination is decreasing. The BTS value decreases with respect to the bedding inclination and the overall trend of it is approximating a linear variation. The 3D digital high-speed camera images reveal that the failure and fracture of a specimen are related to the surface deformation. Layered sandstone tested under uniaxial compression does not show a typical failure mode, although shear slip along the bedding plane occurs at high bedding inclinations. Strain gauge readings during the Brazilian tests indicate that the normal stress on the bedding plane transforms from compression to tension as the bedding inclination increases. The stress parallel to the bedding plane in a rock material transforms from tension to compression and agrees well with the fracture patterns; “central fractures” occur at bedding inclinations of 0°–75°, “layer activation” occurs at high bedding inclinations of 75°–90°, and a combination of the two occurs at 75°.

A Citizen Science Initiative to Understand Community Response to the Kaikōura Earthquake and Tsunami Warning in Petone and Eastbourne, Wellington, Aotearoa/New Zealand

Research Article| May 01, 2018 A Citizen Science Initiative to Understand Community Response to the Kaikōura Earthquake and Tsunami Warning in Petone and Eastbourne, Wellington, Aotearoa/New Zealand Denise Blake; Denise Blake aJoint Centre for Disaster Research, Massey University, P.O. Box 756, Wellington 6140, Aotearoa/New Zealand, d.blake@massey.ac.nz Search for other works by this author on: GSW Google Scholar David Johnston; David Johnston aJoint Centre for Disaster Research, Massey University, P.O. Box 756, Wellington 6140, Aotearoa/New Zealand, d.blake@massey.ac.nz Search for other works by this author on: GSW Google Scholar Graham Leonard; Graham Leonard bJoint Centre for Disaster Research, GNS Science, P.O. Box 30 368, Lower Hutt 5010, Aotearoa/New Zealand Search for other works by this author on: GSW Google Scholar Lisa McLaren; Lisa McLaren aJoint Centre for Disaster Research, Massey University, P.O. Box 756, Wellington 6140, Aotearoa/New Zealand, d.blake@massey.ac.nz Search for other works by this author on: GSW Google Scholar Julia Becker Julia Becker bJoint Centre for Disaster Research, GNS Science, P.O. Box 30 368, Lower Hutt 5010, Aotearoa/New Zealand Search for other works by this author on: GSW Google Scholar Author and Article Information Denise Blake aJoint Centre for Disaster Research, Massey University, P.O. Box 756, Wellington 6140, Aotearoa/New Zealand, d.blake@massey.ac.nz David Johnston aJoint Centre for Disaster Research, Massey University, P.O. Box 756, Wellington 6140, Aotearoa/New Zealand, d.blake@massey.ac.nz Graham Leonard bJoint Centre for Disaster Research, GNS Science, P.O. Box 30 368, Lower Hutt 5010, Aotearoa/New Zealand Lisa McLaren aJoint Centre for Disaster Research, Massey University, P.O. Box 756, Wellington 6140, Aotearoa/New Zealand, d.blake@massey.ac.nz Julia Becker bJoint Centre for Disaster Research, GNS Science, P.O. Box 30 368, Lower Hutt 5010, Aotearoa/New Zealand Publisher: Seismological Society of America First Online: 01 May 2018 Online Issn: 1943-3573 Print Issn: 0037-1106 © Seismological Society of America Bulletin of the Seismological Society of America (2018) 108 (3B): 1807–1817. https://doi.org/10.1785/0120170292 Article history First Online: 01 May 2018 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Denise Blake, David Johnston, Graham Leonard, Lisa McLaren, Julia Becker; A Citizen Science Initiative to Understand Community Response to the Kaikōura Earthquake and Tsunami Warning in Petone and Eastbourne, Wellington, Aotearoa/New Zealand. Bulletin of the Seismological Society of America 2018;; 108 (3B): 1807–1817. doi: https://doi.org/10.1785/0120170292 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyBulletin of the Seismological Society of America Search Advanced Search Abstract On the 14 November 2016, an M 7.8 earthquake occurred in the northeast of the South Island of Aotearoa/New Zealand, causing damage to homes and disrupting critical infrastructure. The earthquake produced a local‐source tsunami that impacted the east coast of the South and North Islands, with the first wave (of a few centimeters height) arriving in the Wellington region within 30 min. The largest waves in Wellington arrived between 1 and 5 hrs after the initial wave and were ∼60 cm in height. Initially, an official “no tsunami threat” message was issued based on scientific interpretation directly following the earthquakes. Scientific advice from Aotearoa/New Zealand (supported by overseas) suggested there was not a tsunami threat. Approximately 1 hr later, this was revised to an official warning stating, “Tsunami threat to Aotearoa/New Zealand” based on updated scientific advice (primarily tide gauge readings), and many communities needed to evacuate, including Petone and Eastbourne in the Hutt Valley, Wellington region, Aotearoa/New Zealand. Approximately three and a half weeks after the earthquake, a survey was undertaken with Petone and Eastbourne residents using a citizen science approach to understand tsunami response and evacuation behaviors. A total of 409 surveys were collected, with 245 respondents from Petone and 164 from Eastbourne. Results established the majority of total respondents evacuated (69%), but only 33% evacuated within the 10‐min natural warning evacuation threshold recommended for local‐source tsunamis. This was despite most respondents saying that the earthquake felt longer than 1 min (64%) and was strong to severe (70%). Only 11% evacuated because of the earthquake. Most (64%) respondents used vehicles to evacuate, causing prohibitive traffic congestion during the evacuation. The results emphasize the need to engage communities to enhance capacity to respond appropriately to both natural and agency‐generated tsunami warnings to ensure community safety and wellbeing in tsunami events. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

A Validation of Observed Meteotsunami in the West Coast of Sri Lanka with European Centre of Medium Range Weather Forecasts (ECMWF) Modelled Data

Metetsunamis are local regional events originating from perturbation of water levels by the impulse of particularly pressure drop in a disturbed atmospheric weather system and amplified to a destructive Tsunami wave with the combined effect of resonance. For the preliminary investigation a Meteotsunami event was analysed for one minute’s frequency data collected in situ sea level measuring station established in Colombo, Sri Lanka under the authority of National Aquatic Resources Research and Development Agency (NARA) with the supervision of Intergovernmental Oceanographic Commission (IOC). The contribution of disturbed weather system was analysed using wind speed (ms-1), atmospheric pressure (hPa) 10 min frequent reading from the Meteorological Department of Sri Lanka and weather station established under the bilateral project of University of Notre dame and NARA. The observed Meteotsunami event was validated using gridded modelled data (12.5 km resolution) obtained from the European Centre of Medium Range Weather Forecasts (ECMWF) and analysed using 6 hourly frequent atmospheric pressure (hPa) data, U and V at wind data at 10 m height and significant wave height. For the identification of Meteotsunami events, observed tide gauge readings were analysed in few different steps. The tidal constituents were quantified using harmonic analysis to obtained astronomical effect removed sea level variation and filtered to isolate Meteotsunami events using math lab software.According to the in situ observation data the atmospheric pressure gradient was recorded as 1008-1001 milibar hours while the modelled value dropped from 1009 to 1002 milibar hours. The observed wind speed was increased from 14.21 to 31.90 mph within 4 hours of time period and ECMWF wind speed increased from 11.02 to 19.94 mph with positive deviation. The observed wave height of Metiotsunami event was >0.3 m while model derived wave height was 0.6 m during the low tide period of the day. According to the threshold criterion suggested by Monserrat for classifying Meteotsunami, resulted wave amplitude of observation data exceeded 4 x σ, where σ is standard deviation of astronomical effect removed residual sea level time series. Further studies are required for the investigation of propagation mechanism with amplifying through the bays with the resonance effects. Further high frequency data are insufficient for the investigation of correlation with synoptic scale meteorological event.The ECMWF model is highly recommended for the prediction of disturbed atmospheric system and related ocean based extreme event forecast for prevention of ocean, atmospheric hazards and mitigation of vulnerability with the effect of global change giving real value of lives in the earth. Keywords: Sea level, Meteotsunami, Tsunami, Atmospheric, Resonance

12.04: Experimental and numerical investigation on the Q690 high strength steel slender columns of welded H‐sections under compression

ABSTRACTThis paper presents the experimental and numerical findings on Q690‐QT high strength steel welded H‐sections. A total of seven slender columns under axial compression were successfully carried out. Four sections of different sectional dimensions were involved. Before testing, the initial out‐of‐straightness of all the specimens were measured. All the tests were conducted in a 1,000 tons universal servo‐controlled testing machine. During the test, displacement transducers were used to record lateral deflections at the mid‐height section and axial deformations at the top ends of all the specimens. Strain gauges were mounted onto the outer surface of the flanges at three sections of each specimen. The strain gauge readings were used to calculate the loading eccentricities at both ends of the columns. All the columns were failed by overall buckling about the minor axes of their cross‐sections and neither weld nor material fracture was found. Separate specimens were fabricated for the measurement of residual stresses of all the sections. The numerical simulation on these tests are also reported. The numerical models were based on the measured geometrical dimensions and material properties of all the specimens. The measured out‐of‐straightness, loading eccentricities, and residual stress patterns were also introduced in the models. These numerical models were proved able to simulate the behaviour for all the test specimen except one, in which the end rotational restraints were significant. Both the test result and the numerical result with normalized initial out‐of‐straightness were compared with the current design codes. It is preliminarily proposed that column buckling curve a in the current design codes may be appropriate for the design of Q690 high strength steel welded H‐sections. And this proposal is need to be confirmed by complementary parametric study in the future.

Cataloguing tsunami events in the UK

Abstract Tsunami catalogues provide important datasets in assessing the risk from infrequent but potentially high-impact events. Although the UK is located away from subduction zones (the most common origin of tsunamis), tsunamis have struck its shores, most notably those triggered by the prehistoric Storegga submarine landslide and the 1755 Lisbon earthquake. Since the major events of 2004 (Indian Ocean) and 2011 (Japan) tsunamis are in the public psyche, even if the risks to UK coasts are not. Due to this heightened awareness, many reported events are claimed to be tsunamis and the potential for tsunamis is increasingly included in risk planning; understanding the true frequency of tsunamis is therefore important. Within the UK, the evidence for tsunamis includes tide gauge readings, reported visual observations and interpretation of sedimentological features. Catalogues need to consider whether the event is a true tsunami in order to avoid a plethora of claims that confound risk assessments; for example, recent well-documented events generated by weather systems (meteotsunamis) provide a possible explanation for some historical events. A detailed examination of the impact of tsunamis upon the UK coast is provided, including examples of events triggered by the three primary causes of tsunamis: seismicity, submarine landslides and coastal landslides.

Buckling of axially compressed CFRP cylinders with and without additional lateral load: Experimental and numerical investigation

Thin-walled structures are widely used in aerospace, offshore, civil, marine and other engineering industries. Buckling of such thin-walled imperfection sensitive structures is a very important phenomenon to be considered during their design phase. Existing design guidelines, being the most known the NASA SP-8007 for cylinders dated from the late 1960's are currently used in the aerospace industry and employ conservative lower-bound knock-down factors. These empirically based lower-bound methods do not include important mechanical properties of laminated composite materials, such as the stacking sequence. New design approaches that allow taking full advantage of composite materials are therefore required.This study deals with buckling experiments of axially compressed, unstiffened carbon fiber–reinforced polymer (CFRP) cylinders with and without an additional lateral load. Two geometrically identical cylinders with the same layup were designed, manufactured and tested. Before testing, the thickness of the cylinders was measured with ultrasonic inspection and the geometry was measured utilizing a 3D scanning system based on photogrammetry. During testing, a digital image correlation system was employed to monitor deformations, strain gage readings and load-shortening data was taken. Modelling of shape mid-surface and thickness imperfections as well as fiber volume fraction correction are included into the Finite Element Analysis (FEA) of the test structures, and the experimental results are compared against FEA results.

Haben Otto Neugebauer und William Feller die Niljahre richtig gemittelt?

Summary Neugebauer critized Meyer’s hypothesis that the 365-day calendar resulted from observation of the heliacal risings of Sothis, maintaining that astronomical observation should have resulted in a year of 365.25 days. Instead, Neugebauer traced the 365-day calendar back to a Nile year based on computational equalization of varying successive intervals between minimum or maximum gauge readings. He did not propose the anachronistic calculation of the arithmetic average but alluded instead to a procedure using stroke marks allegedly resulting in years of 365 full days, while neglecting the quarter-day. Neugebauer and his collaborator Feller overlooked the fact that four successive years of 365.25 days equal 1461 full days and that the sums of numerous successive intervals between the same gauge values fractionize into multiples of Nile years of 365 and 366 full days. Thus, a revised analysis of long-term Nile year statistics produces the same results as a short-term observation of the heliacal risings of Sirius.

AN OVERVIEW OF DROUGHT ANALYSIS: ASSESSING DROUGHT SEVERITY BASED ON FLUCTUATION IN RAINFALL TREND BY STANDARD PRECIPITATION INDEX FOR SHIVAMOGGA DISTRICT

The Standard precipitation index expresses the actual rainfall as a standardized departure with respect to rainfall probability distribution function and hence the index has gained importance in recent years as a potential job indicator permitting comparison across space and time. The computation of SPI requires long term data on precipitation.
 Droughts are hydro metrological events affecting vast regions and causing significant structural and non-structural damages. Drought predictions may prevent these type of adverse consequences to a significant extant.
 This work regarding the drought analysis by assessing the drought severity based on fluctuation in rainfall trend by standard precipitation index for Shivamogga district by 30years rainfall data from rain gauge reading of different station in different Taluk of Shivamogga district.

Erratum

Structural ConcreteVolume 18, Issue 2 p. 376-376 ERRATUMFree Access Erratum This article corrects the following: Structural performance of corner joints subjected to a closing moment using mechanical anchorages: an experimental study Francesco Marchetto, Alejandro Pérez Caldentey, Hugo Corres Peiretti, Volume 17Issue 6Structural Concrete pages: 987-1002 First Published online: January 3, 2017 First published: 16 February 2017 https://doi.org/10.1002/suco.201700130AboutSectionsPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat This paper1 was originally published with an incorrect caption for Fig. 19. The caption should read as follows: Fig. 19. Gauge readings: 25-TH-16 This has now been corrected in the online version of the article. REFERENCE 1 Marchetto F, Pérez Caldentey A, Corres Peiretti H. Structural performance of corner joints subjected to a closing moment using mechanical anchorages: an experi mental study. Struct Concr. 2016; 17: 987- 1002. doi:10.1002/suco.201500222. Volume18, Issue2April 2017Pages 376-376 ReferencesRelatedInformation

Delivering occupational therapy hand assessment and treatment sessions via telehealth

Introduction Telehealth offers a solution to assist delivery of occupational therapy (OT) services for hand therapy in rural and remote locations. However, there is currently no evidence to validate this service model. The aim of this study was to examine the validity of clinical decisions made during hand therapy sessions conducted via telehealth compared to a traditional clinical model (TCM) assessment, and explore patient and clinician satisfaction. Methods Eighteen patients referred for hand therapy to a rural/remote hospital-based outpatient service were assessed simultaneously via telehealth and a TCM assessment. An allied health assistant supported data collection at the patient end. Hand function was assessed using a range of objective measures, subjective scales and patient reported information. Minimal level of percent exact agreement (PEA) between the telehealth OT (T-OT) and the TCM-OT was set at ≥80%. Results Level of agreement for all objective measures (dynamometer and pinch gauge reading, goniometer flexion and extension, circumference in millimetres) ranged between 82% and 100% PEA. High agreement (>80% PEA) was also obtained for judgements of scar and general limb function, exercise compliance, pain severity and sensitivity location, activities of daily living and global ratings of change (GROC) scores. There was 100% PEA for overall recommendations. Minimal technical issues were experienced. Patient and clinician satisfaction was high. Discussion Clinical decisions made via telehealth were comparable to the TCM and consumers were satisfied with telehealth as a service option. Telehealth offers the potential to improve access to hand therapy services for rural and remote patients.

Slaugytojų žinios apie tracheostomos vamzdelio manžetės priežiūrą prieš ir po mokymo

Tracheostomos vamzdelio manžetės priežiūra yra susijusi su didele rizika paciento sveikatai, todėl svarbu, kad slaugytojai turėtų mokslo įrodymais pagrįstų žinių apie manžetės priežiūrą. Jeigu slaugytojai turės pakankamai žinių ir gerus praktinius įgūdžius kokybiškai atlikti šią procedūrą, tai iki minimumo sumažins galimų nepageidaujamų įvykių dažnumą, užtikrins paciento saugumą. Darbo tikslas išanalizuoti slaugytojų žinias apie tracheostomos vamzdelio manžetės priežiūrą prieš ir po mokymo. Tyrimas vyko 2013 m. Kauno miesto ligoninių skyriuose, į kuriuos tracheostomuoti pacientai dažniausiai patenka iš Intensyviosios terapijos skyrių. Dalyvauti tyrime buvo pakviesti visi 111 tuose skyriuose dirbančių slaugytojų. Tyrimas buvo vykdomas etapais: 1) slaugytojų anketinė apklausa prieš mokymus; 2) slaugytojų mokymai; 3) slaugytojų apklausa po mokymų. Apklausoje prieš mokymus dalyvavo 93 slaugytojai, po mokymo – 81. Tyrimo duomenims rinkti buvo naudojama autorių sukurta Slaugytojų žinių nustatymo anketa. Rezultatai. Dauguma apklaustų slaugytojų teigė, jog manžetės slėgio specialiu manometru nematuoja (prieš mok. - 95,2 proc., po mok. - 98,3 proc.). Prieš ir po mokymų beveik pusė slaugytojų teigė, kad niekada nepripučia oro į tracheostomos vamzdelio manžetę (prieš mok. - 47,6 proc., po mok. - 45,8 proc.). Po mokymo statistiškai reikšmingai daugiau slaugytojų (44,4 proc.) nurodė, kad orą iš tracheostomos vamzdelio manžetės išleidžia kas tris – keturias val., o prieš mokymą taip darantys nurodė tik 20,1 proc. respondentų (χ²=12,162; lls=1; p=0,007). Prieš mokymą 60,9 proc. tiriamųjų nurodė, kad visai neišleidžia oro iš tracheostomos vamzdelio manžetės, o po mokymo taip teigė 40,3 proc. slaugytojų (χ²=12,162; lls=1; p=0,007). Po mokymo 50,6 proc. slaugytojų nurodė, kad manžetės slėgis turi būti mažesnis nei 20 cmH2O, nors prieš mokymą tokį slėgį nurodė 3,6 proc. respondentų (χ²=59,048; lls=3; p<0,001). Po mokymo 21,0 proc. tiriamųjų manė, kad nesvarbu, koks slėgis tracheostomos vamzdelyje, svarbu kad būtų daug išpūsta, o prieš mokymą taip teigė 65,5 proc. apklausoje dalyvavusių slaugytojų (χ²=59,048; lls=3; p<0,001). Didžioji dalis (79,6 proc.) slaugytojų, kurie išsimokslinimą įgijo medicinos mokykloje, po mokymo teigė, kad prieš išleidžiant orą iš tracheostomos vamzdelio manžetės išsiurbia sekretą iš burnos ir nosiaryklės, nors prieš mokymą taip teigė darantys 51,7 proc. respondentų (χ²=9,007; lls=1; p=0,003). Išvados. Po mokymo reikšmingai didesnė dalis slaugytojų teisingai nurodė, kad orą iš tracheostomos vamzdelio manžetės išleidžia kas tris – keturias val.; o manžetės slėgis turi būti ne mažesnis nei 20 cmH2O. Reikšmingai didesnė dalis slaugytojų, kurie išsimokslinimą įgijo medicinos mokykloje, po mokymo teigė, kad prieš išleidžiant orą iš tracheostomos vamzdelio manžetės išsiurbia sekretą iš burnos ir nosiaryklės. Prieš ir po mokymų dauguma apklaustųjų teigė, jog manžetės slėgio specialiu manometru nematuoja, o oro į vamzdelio manžetę pagal manometro rodiklius pripučia tik nedidelė dalis slaugytojų.

Thickness measuring of electroconductive pipe walls using the dual-frequency eddy-current method

The paper describes a dual-frequency method for reducing the impact of changes in the gap size between the eddy-current transducer and the pipe, as well as the pipe electrical conductivity on the eddy-current thickness gauge readings. A block-diagram of the dual-frequency eddy-current thickness gauge is proposed for light-alloy drill pipes. The amplitude and signal phase dependencies on the wall thickness in the range from 6 to 17 mm and the gap in the range from 0 to 13.5 mm were studied, the results are presented. The digital signal processing algorithms based on the piecewise-linear approximation of low-frequency and high-frequency signal phase dependencies on the wall thickness are proposed. It is shown that the proposed correction algorithms can reduce the error caused by variations of electrical conductivity and the gap between the transducer and the pipe.

Comparative Analysis of the Effect of Thermal Cycling on Fatigue Behavior of Low and Medium Carbon Steel

This paper presents the technique with which Low frequency thermal cycling tests were carried out on two carbon steel. The steels used are low and medium carbon steel, the compositional analysis was done to ascertain the percentage of carbon the as-received materials contain, and the micrograph of the samples was done using acuscope photomicrograph with a magnification of X400. The heating of the samples was done in a carbon muffle furnace and the test was done at predetermined ranges of thermal cycling temperatures. The specimen were machined to a precise gage length and diameter and the test was performed with the use of Avery Dennison (Avery model 7305) which has a curve with which the relationship between the dial gage reading and the imposed torque was established. The results obtained from the machine were the readings for maximum bending moment and cycles to failure, which were converted to get the applied bending stress. On the final analysis medium carbon steel prove to be a suitable material for design of machine that could undergo thermal cycling in service condition beyond 230°C.

Forces between permanent magnets: experiments and model

This work describes a very simple, low-cost experimental setup designed for measuring the force between permanent magnets. The experiment consists of placing one of the magnets on a balance, attaching the other magnet to a vertical height gauge, aligning carefully both magnets and measuring the load on the balance as a function of the gauge reading. A theoretical model is proposed to compute the force, assuming uniform magnetisation and based on laws and techniques accessible to undergraduate students. A comparison between the model and the experimental results is made, and good agreement is found at all distances investigated. In particular, it is also found that the force behaves as r−4 at large distances, as expected.