scholarly journals Measurement Of The Dynamics Of The Sheave Block Of Shipyard Crane With 1000 T Lifting Capacity For Verification Of The Laboratory Stand

2021 ◽  
Vol 93 (7s) ◽  
pp. 96-109
Author(s):  
Piotr Szymak ◽  
◽  
Paweł Piskur ◽  
Jacek Goszczyński ◽  
Tomislav Batur ◽  
...  

The paper includes partial results of the development project entitled “The first Polish gantry crane with high lifting capacity for the shipbuilding industry adapted to work in difficult wind conditions – development and demonstration” (no POIR.01.02.00-00-0017/18). Due to the requirements of working in challenging wind conditions, the crane will be equipped with the sheave block with a hook operating automatically. To resolve this problem, mathematical and then physical models of the innovative crane are required. Therefore, to obtain reliable models, the measurement of the dynamics of the sheave block of crane with high lifting capacity was carried out. At the beginning of the paper, the conditions and used measurement stand are included. Then, the time and frequency analysis of the received measurement results are described. Moreover, the determination of the crane parameters is also presented. The analysis results will be used in further research to tune both the simulation and the physical models of the crane with an automatic hook, which are being developed.

2015 ◽  
Vol 97 (1) ◽  
pp. 71-79 ◽  
Author(s):  
Daria Filipiak ◽  
Waldemar Kamiński

AbstractElectronic tacheometers are currently the standard instruments used in geodetic work, including also geodetic engineering measurements. The main advantage connected with this equipment is among others high accuracy of the measurement and thus high accuracy of the final determinations represented for example by the points’ coordinates. One of many applications of the tacheometers is the measurement of crane rail axes. This measurement is based on polar method and it allows to get the spatial coordinates of points in 3D local system. The standard technology of measurement of crane rail axes and development of its calculations’ results is well-known and widely presented in the subject literature. At the same time new methods of observations results evaluation are developing.Some new proposals for the development of measurement results were already presented in (Kamiński, 2013).This paper is a generalisation of the paper quoted above. The authors developed the concept which was presented there by a proposal for determining rectification corrections for semi gantry crane rail axes. To carried out the task, the parametric method with conditions on parameters was used. Moreover the practical tests on simulated measurement results were conducted. The results obtained from alignment confirmed the theoretical assumptions.Despite the fact that analyses were carried out only on the simulated data, it is already possible to say that presented method for determination of rectification corrections for crane rail axes can be used for development of the observations from real measurement.


Author(s):  
Ingrid Kästel ◽  
Giles de Quincey ◽  
Jörg Neugebauer ◽  
Robert Sader ◽  
Peter Gehrke

Abstract Background There is disagreement about the optimal torque for tightening smartpegs for resonance frequency analysis (RFA). Subjective finger pressure during hand tightening could affect the reliability of the resulting values. The aim of the current study was therefore to assess whether or not the insertion torque of a smartpeg magnetic device influences the implant stability quotient (ISQ) value during RFA. Methods Thirty self-tapping screw implants (XiVE S, Dentsply Sirona Implants, Bensheim, Germany) with a diameter of 3.8 mm and a length of 11 mm were inserted in three cow ribs with a bone quality of D1. The RFA value of each implant was measured (Ostell, FA W&H Dentalwerk, Bürmoos, Austria) in two orthogonal directions (mesial and buccal) after tightening the corresponding smartpeg type 45 with a mechanically defined value of 5 Ncm (Meg Torq device, Megagen, Daegu, South Korea) (test). Additionally, 4 different examiners measured the RFA after hand tightening the smartpegs, and the results were compared (control). Insertion torque values were determined by measuring the unscrew torque of hand seated smartpegs (Tohnichi Manufacturing Co. Ltd, Tokyo, Japan). Results The ISQ values varied from 2 to 11 Ncm by hand tightening and from 2 to 6 Ncm by machine tightening. The comparison of hand and machine tightening of smartpegs displayed only minor differences in the mean ISQ values with low standard deviations (mesial 79.76 ± 2,11, buccal 77.98 ± 2,) and no statistical difference (mesial p = 0,343 and buccal p = 0,890). Conclusions Manual tightening of smartpeg transducers allows for an objective and reliable determination of ISQ values during RFA.


Universe ◽  
2021 ◽  
Vol 7 (7) ◽  
pp. 222
Author(s):  
Maxim Khlopov

A.D. Sakharov’s legacy in now standard model of the Universe is not reduced to baryosynthesis but extends to the foundation of cosmoparticle physics, which studies the fundamental relationship of cosmology and particle physics. Development of cosmoparticle physics involves cross-disciplinary physical, astrophysical and cosmological studies of physics Beyond the Standard model (BSM) of elementary particles. To probe physical models for inflation, baryosynthesis and dark matter cosmoparticle physics pays special attention to model dependent messengers of the corresponding models, making their tests possible. Positive evidence for such exotic phenomena as nuclear interacting dark atoms, primordial black holes or antimatter globular cluster in our galaxy would provide the selection of viable BSM models determination of their parameters.


2014 ◽  
Vol 45 (2) ◽  
pp. 64 ◽  
Author(s):  
Chiara Cevoli ◽  
Angelo Fabbri ◽  
Simone Virginio Marai ◽  
Enrico Ferrari ◽  
Adriano Guarnieri

Thermal conductivity of a food material is an essential physical property in mathematical modelling and computer simulation of thermal processing. Effective thermal conductivity of non-homogeneous materials, such as food matrices, can be determined experimentally or mathematically. The aim of the following research was to compare the thermal conductivity of short pastry biscuits, at different baking stages (60-160 min), measured by a line heat source thermal conductivity probe and estimated through the use of thermo-physical models. The measures were carried out on whole biscuits and on powdered biscuits compressed into cylindrical cases. Thermal conductivity of the compacted material, at different baking times (and, consequently at different moisture content), was then used to feed parallel, series, Krischer and Maxwell-Eucken models. The results showed that the application of the hot wire method for the determination of thermal conductivity is not fully feasible if applied directly to whole materials due to mechanical changes applied to the structure and the high presence of fats. The method works best if applied to the biscuit component phases separately. The best model is the Krischer one for its adaptability. In this case the value of biscuit thermal conductivity, for high baking time, varies from 0.15 to 0.19 Wm<sup>–1</sup> K<sup>–1</sup>, while the minimum, for low baking time, varies from 0.11 to 0.12 Wm<sup>–1</sup> K<sup>–1</sup>. These values are close to that reported in literature for similar products.


1992 ◽  
Vol 92 (3) ◽  
pp. 1564-1568 ◽  
Author(s):  
Hiroyuki Hachiya ◽  
Shigeo Ohtsuki ◽  
Motonao Tanaka ◽  
Floyd Dunn

2017 ◽  
Author(s):  
Angel J. Gomez-Pelaez ◽  
Ramon Ramos ◽  
Emilio Cuevas ◽  
Vanessa Gomez-Trueba ◽  
Enrique Reyes

Abstract. At the end of 2015, a CO2/CH4/CO Cavity Ring-Down Spectrometer (CRDS) was installed at the Izaña Global Atmosphere Watch station (Tenerife, Spain) to improve the Izaña Greenhouse gases GAW measurement programme, and to guarantee the renewal of the instrumentation and the long-term maintenance of this programme. We present the results of the CRDS acceptance tests, the processing of raw data applied through novel numerical codes, and the response functions used. Also, the calibration results, the implemented water vapour correction, the target gas injection statistics, the ambient measurements performed from December 2015 to July 2017, and their comparison with other continuous in situ measurements are described. The agreement with other in situ continuous measurements is good most of the time for CO2 and CH4, but for CO is just outside the GAW 2-ppb objective. It seems the disagreement is not produced by significant drifts in the CRDS CO WMO tertiary standards. The main novelties are: 1) determination of a slight CO2 correction that takes into account changes in the inlet pressure/flow rate; 2) detailed justification of the use of virtual tanks to monitor the response function changes in time; 3) drift rate determination for the pressure and temperature sensors located inside the CRDS cavity; 4) novelties in the determination of the H2O correction for CO; and 5) determination and discussion of the origin of the CRDS-flow inlet pressure and H2O dependences.


2021 ◽  
pp. 187-190
Author(s):  
D.А. Hakimov ◽  
I.V. Zhuk ◽  
M.K. Kievets

Experimental studies have been carried out to determine the sensitivity of a mobile scintillation gamma-spectrometer to radon-222 in mineral water samples for the selected measurement geometry and the minimum measurable activity of radon-222 in such samples. The measurement results of radon content in mineral water samples obtained using such gamma-spectrometer are presented too.


2013 ◽  
Vol 6 (1) ◽  
Author(s):  
Thierry Laliberté ◽  
Clément Gosselin

The concept of polyhedra with articulated faces is investigated in this paper. Polyhedra with articulated faces can be described as polyhedral frameworks, whose faces are constrained to remain planar. A mechanical arrangement based on a single type of component is proposed for the construction of the polyhedra. Then, the determination of their infinitesimal and full-cycle mobility is addressed. In some cases, they are rigid structures while in others they are articulated mechanisms. Finally, examples are given, using simulation and physical models, and several new families of articulated polyhedra are synthesized.


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