scholarly journals Ways to Increase the Efficiency of Thermopressiometry

2021 ◽  
pp. 84-91
Author(s):  
V. Y Ulyanov
Keyword(s):  
Deformation Modulus ◽  
Probe Design ◽  
Frozen Soils ◽  
Engineering Research ◽  
Soil Sediment ◽  
Thawing Depth ◽  
Sediment Deformation ◽  
Improved Design ◽  
First Time ◽  
Conductive System

Purpose. The purpose of the work is to identify the ways to increase the efficiency of engineering research, based on the significant amount of exploration work required in the creation of modern man-made objects, taking into account the shortcomings of existing instruments and equipment used to measure soil stress, and in relation to the need to improve the design of thermopressiometers, which are aimed to facilitate the study of frozen soils. Methodology. The ways to improve the blade thermopressiometer for the study of frozen soils with different aggregates were selected by the comparative-analytical method and the method of analogy. Thawing depth, absolute soil sediment, deformation modulus etc. were determined by thermal-technical calculations. Findings. The application issues of concern of the existing thermopressiometers (limited research of soils of a certain type, complexity and insufficient accuracy of readings) identified can be overcome by the proposed improved design of a blade thermopressiometer for testing frozen sandy-clay soils. It is based on the improved heating circuit, the applicationd of quality materials and changing the form of the blades and body. The device is intented for use on permafrost and natural frozen soils of the world, including Ukraine. Originality. For the first time we offered a model of an advanced thermopressiometer with an improved body shape made of high-quality corrosion-resistant materials, including non-metallic ones. It has the reduced number of blades to one retractable sector blade-stamp (square or round) and one heating blade-stamp. A special probe design with mechanical/hydraulical sensor drive with a thermocouple (or with two fork probes to improve the measurements) was proposed. It was also recommended to introduce an electric conductive system designed for thawed soils, with a rod for measuring the retractable blade-stamp. The possibility of using a thermopressiometer during the study of seasonally frozen soils is established. Practical value. Improving the device model should facilitate its application in engineering and geological research for various types of construction, including transport, hydraulic engineering, which use the methods of deep freezing of weak and unstable soils.

The effects of dehydration and local soil on parasite recovery: A preliminary paleoparasitological evaluation on experimental coprolites

The Holocene ◽  
2021 ◽  
pp. 095968362110499
Author(s):  
Darío Alejandro Ramirez ◽  
Mariana Fabra ◽  
Samanta Xavier ◽  
Alena Mayo Iñiguez
Keyword(s):  
Equal Mass ◽  
Central Argentina ◽  
Soil Sediment ◽  
Local Soil ◽  
Before And After ◽  
Fresh Feces ◽  
Flotation Technique ◽  
First Time ◽  
Taphonomic Processes

Experimental paleoparasitological approaches have been used in order to optimize the methodology previously to the application in archeological samples. In this study we evaluated the action of dehydration and local soil (Central Argentina) on the loss of parasite eggs in experimental coprolites, using two parasitological techniques: spontaneous sedimentation and sucrose-flotation. Experimental coprolites comprised fresh human feces, positive for Hymenolepis nana, Ascaris sp., and Enterobius vermicularis, submitted to controlled artificial dehydration. Experimental coprolites with soil addition were prepared by mixing archeological sediment with equal mass of fresh feces. Helminth eggs were counted and eggs per gram were estimated in each subsample. Statistical analyses were applied to compare subsamples before and after desiccation and with and without addition of soil sediment. The performance of parasitological methods statistically differed, the sucrose flotation technique being the less effective when fresh feces and experimental coprolites were analyzed. Partial deformation of eggs was observed via both techniques only in subsamples containing H. nana eggs. However, this was not seen in Ascaris sp. subsamples, possibly due to eggshell composition. We found that sample desiccation significantly decreased the number of eggs in the experimental coprolites. Mixing archeological sediment with the fecal material also resulted in significantly fewer eggs surviving, independent of desiccation. This shows that climate and soil in which archeological fecal samples are found can strongly influence the survival of parasite eggs from past populations. The small amount of parasite evidence often found in paleoparasitological analyses, including Central Argentina, could be attributed to the action of taphonomic processes rather than to the real absence of infection in these ancient populations. Importantly, the study highlights the role of local soil, confirmed for the first time by empirical data. The research provides valuable insights into the understanding of the paleoparasitological results of the region and of general paleoparasitology.

Use of Remote Sensing Technologies for Building Damage Assessment after the 2003 Bam, Iran, Earthquake—Preface to Remote Sensing Papers

2005 ◽  
Vol 21 (1_suppl) ◽  
pp. 207-212 ◽  
Author(s):  
Ronald T. Eguchi ◽  
Babak Mansouri
Keyword(s):  
Remote Sensing ◽  
Earthquake Engineering ◽  
Damage Assessment ◽  
Building Damage ◽  
Remotely Sensed Data ◽  
Engineering Research ◽  
Earthquake Loss ◽  
Earthquake Damage Detection ◽  
Response Decisions ◽  
First Time

This preface introduces a series of papers that describe the use of remote sensing technologies in quantifying the extent of building damage after the 2003 Bam, Iran, earthquake. These papers represent a significant milestone in post-earthquake loss estimation. For the first time, independent evaluations of regional damage are documented, which will ultimately allow an assessment of the efficacy of these technologies as tools for post-earthquake damage detection and quantification. Not only were different sensors used, but radically different approaches were implemented in quantifying damage. The conclusions and recommendations of the different papers are generally consistent and strongly suggest that regional damage assessment using remotely sensed data is highly feasible. The papers, however, acknowledge that more research is needed before these technologies can be used to make critical emergency response decisions. Finally, the role of the Earthquake Engineering Research Institute through its Learning From Earthquakes Program is acknowledged, largely for helping to promote the use of remote sensing technologies in earthquake studies and for recognizing the value of collaboration through its newly formed Subcommittee on Remote Sensing.

Autonomous performance maximization of research-based hybrid unmanned aerial vehicle

2020 ◽  
Vol 92 (4) ◽  
pp. 645-651
Author(s):  
Sezer Çoban
Keyword(s):  
Unmanned Aerial Vehicle ◽  
Performance Optimization ◽  
Flight Trajectory ◽  
Content Type ◽  
Lateral Dynamics ◽  
Aerial Vehicle ◽  
Improved Design ◽  
Autopilot Systems ◽  
First Time ◽  
Practical Implications

Purpose This paper aims to investigate the autonomous performance optimization of a research-based hybrid unmanned aerial vehicle (i.e. HUAV) manufactured at Iskenderun Technical University. Design/methodology/approach To maximize the autonomous performance of this HUAV, longitudinal and lateral dynamics were initially obtained. Then, the optimum magnitudes of the autopilot system parameters were estimated by considering the vehicle’s dynamic model and autopilot parameters. Findings After determining the optimum values of the longitudinal and lateral autopilots, an improved design for the autonomously controlled (AC) HUAV was achieved in terms of real-time flight. Practical implications Simultaneous improvement of the longitudinal and lateral can be used for better HUAV operations. Originality/value In this paper, the autopilot systems (i.e. longitudinal and lateral) of an HUAV are for the first time simultaneously designed in the literature. This helps the simultaneous improvement of the longitudinal and lateral flight trajectory tracking performances.

IMPROVED DESIGN OF A HEAD OF A TOTAL HIP REPLACEMENT

2020 ◽  
Vol 4 (1) ◽  
pp. 139-143
Author(s):  
V.I. PAKHALIUK ◽  
A.M. POLIAKOV
Keyword(s):  
Titanium Alloy ◽  
Total Hip Replacement ◽  
Hip Replacement ◽  
Low Cost ◽  
Friction Couple ◽  
Element Analysis ◽  
Total Hip ◽  
Improved Design ◽  
First Time ◽  
Soldered Joint

For the first time, the design of a modular ceramic head of a total hip replacement (THR) has been developed, which has the properties of a metal in join with the stem neck and the properties of a ceramic on the bearing surface of a friction couple. This is achieved by creating a low-cost, low-toxic, strong connection of alumina or zirconium ceramics and a titanium alloy to obtain a soldered joint that is efficient in human synovial fluid. With the help of finite element analysis, a qualitative and quantitative assessment of the strength and rigidity of the proposed head design has been made. Also shown is an image of a finished soldered head made of alumina ceramic with a sleeve made of titanium alloy VT1-0.

scholarly journals CONE PENETRATION TESTING AND SAMPLING OF FROZEN SOILS

Gruntovedenie ◽  
2021 ◽  
Vol 1 (16) ◽  
pp. 53-64
Author(s):  
Daniil Lagosha ◽  
◽  
Nikolay Volkov ◽  
Ivan Sokolov
Keyword(s):  
Statistical Data ◽  
Silty Clay ◽  
Test Results ◽  
Cone Penetration ◽  
Frozen Soils ◽  
Penetration Testing ◽  
Cone Penetration Testing ◽  
Permafrost Soils ◽  
First Time

The article provides the analysis of the results of the permafrost soils field and laboratory tests. The undisturbed permafrost samples were collected using cone penetration testing (CPT) equipment and MOSTAP sampler. The sampling technology using CPT equipment was applied on permafrost soils for the first time. The full scope of tests for physical properties were carried out on the collected samples. Based on the test results, several engineering-geological elements (EGE) were identified and confirmed, one of which is composed of frozen silty clay. The results of statistical data processing were compared. The data on the coefficient of variation of the values of the ultimate long-term resistivity of soils against cone penetration (characteristic of long-term strength) for the frozen EGE are presented.

scholarly journals IMPROVED DESIGN TECHNIQUE FOR CONDUCTING PARTS OF ELECTROMAGNETIC CONTACTORS

2021 ◽  
pp. 73-82
Author(s):  
Ivan P. Ivanov ◽  
Dmitriy V. Samuilov ◽  
Gennadiy P. Svintsov ◽  
Alexey A. Fedimirov ◽  
Evgeniy V. Shpakov
Keyword(s):  
Temperature Distribution ◽  
Heating Temperature ◽  
Infinite Length ◽  
Design Technique ◽  
Distribution Constant ◽  
Improved Design ◽  
Almost All ◽  
Improved Technique ◽  
First Time

The existing design techniques for the conductive parts of the main circuit of electromagnetic contactors are based on two assumptions: the infinite length of the conductor and the absence of its heating, which is determined by the contact resistance. This can lead to significant errors in the design of conductors of finite length, primarily in the design of conductive parts with contact bridges, which contain almost all modern electromagnetic contactors. For a more efficient determination of the geometric parameters of the conductive parts, it is proposed to use an improved technique without the above assumptions. The technique uses a model of a contact formed by overlapping the ends of two rectangular conductors and containing a contact piece as a design one. A key feature of the technique is the use in the calculations of the temperature distribution constant along the length of the conductor, introduced for the first time, which determines the nature of the change in its heating temperature. The main stages of calculation and an example of determining the geometric dimensions of the conductive parts by this method for ABB contactors for different rated currents are given.

scholarly journals Measurement of the polarisation in the auroral N2+ 427.8 nm band

2019 ◽  
Vol 9 ◽  
pp. A26 ◽  
Author(s):  
Mathieu Barthelemy ◽  
Hervé Lamy ◽  
Anne Vialatte ◽  
Magnar Gullikstad Johnsen ◽  
Gaël Cessateur ◽  
...  
Keyword(s):  
Emission Lines ◽  
Data Set ◽  
Auroral Emission ◽  
Integration Period ◽  
Data Analysis Procedure ◽  
Improved Design ◽  
Blue Line ◽  
The Individual ◽  
First Time ◽  
Linear Polarisation

In this paper, we provide for the first time polarisation measurements of the N+2 band at 427.8 nm performed with Premier Cru, a dedicated spectropolarimeter to investigate the polarisation of auroral emission lines between 400 and 700 nm. Details about the instrument, the observing conditions and the data analysis procedure are provided. Results obtained during three nights in March 2017 in Skibotn, Norway, indicate that the auroral blue line is polarised with a degree of linear polarisation of a few %. Due to weak Signal-to-Noise Ratios (SNR), these measurements still need to be taken with caution since none of the individual data set has a detection with a 3σ confidence level. However, results integrated over the entire observing period each night do show a 3σ detection but due to the long integration period, the origin of this polarisation cannot be linked to a specific type of aurora (diffuse vs structured arc) or specific ionospheric or geomagnetic conditions. These observations need to be confirmed with an improved design to increase the SNR and decrease the exposure time. When available, these improved measurements of the blue line polarisation will be important to better understand the physics of auroral processes at altitudes below 100 km where the N2+ emission occurs and possibly for space weather applications if the polarisation varies with ionospheric/geomagnetic conditions.

Annulate lamellae in the Sertoli cells of guinea pig testis after unilateral torsion of the spermatic cord

1984 ◽  
Vol 42 ◽  
pp. 196-197
Author(s):  
J. Chakraborty ◽  
A. P. Sinha Hikim ◽  
J. S. Jhunjhunwala
Keyword(s):  
Sertoli Cells ◽  
Guinea Pigs ◽  
Spermatic Cord ◽  
Present Report ◽  
Cell Types ◽  
Annulate Lamellae ◽  
Spermatogenic Cells ◽  
Electron Microscopic ◽  
Structural Details ◽  
First Time

Although the presence of annulate lamellae was noted in many cell types, including the rat spermatogenic cells, this structure was never reported in the Sertoli cells of any rodent species. The present report is based on a part of our project on the effect of torsion of the spermatic cord to the contralateral testis. This paper describes for the first time, the fine structural details of the annulate lamellae in the Sertoli cells of damaged testis from guinea pigs.One side of the spermatic cord of each of six Hartly strain adult guinea pigs was surgically twisted (540°) under pentobarbital anesthesia (1). Four months after induction of torsion, animals were sacrificed, testes were excised and processed for the light and electron microscopic investigations. In the damaged testis, the majority of seminiferous tubule contained a layer of Sertoli cells with occasional spermatogonia (Fig. 1). Nuclei of these Sertoli cells were highly pleomorphic and contained small chromatinic clumps adjacent to the inner aspect of the nuclear envelope (Fig. 2).

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