Analysis of the conductivity property of live working shielding clothing

2017 ◽  
Vol 48 (3) ◽  
pp. 643-659 ◽  
Author(s):  
Ying Su ◽  
Xiuchen Wang ◽  
Yaping Li ◽  
Zhen Pan ◽  
Zhe Liu
Keyword(s):  
Electromagnetic Waves ◽  
Structural Complexity ◽  
Measuring Point ◽  
Conductivity Property ◽  
Structure Line ◽  
Design Production ◽  
Point To Point ◽  
Representative Points ◽  
The Relationship ◽  
Resistance Value

Live working shielding clothing must be worn when working under the high-pressure environment. High voltage and electromagnetic waves are shielded by conducting principle, so as to reduce the harm to human body. At present, the relationship between the point to point resistance and the structure of clothing is not clear in the production and research of shielding clothing, its design, production, and test lack of theoretical guidance. In this paper, the electrical conductivity of the clothing is studied by measuring the point to point resistance of shielding clothing. The suitable method of measuring point to point resistance is designed, and test platform is build by U610E's digital multimeter and homemade special electrode and other equipment. The representative points are selected from the main latitude lines of clothing and the parts of contacting electrified equipment when wearing clothes, then measure the resistance value between different points. Through the analysis of the experimental results it can be found that, on the basis of good connection, the farther the distance between two points, the smaller the resistance value and the better the connectivity; the resistance value of the points that frequently contact with electrified equipment is significantly smaller than others; about the same distance of two points, if there is structure line in the middle, the resistance value is large; the structural complexity is proportional to the resistance value. It is concluded that the point to point resistance of shielding garment is related to the parts of contacting with electrified equipment during operation, the complexity of structure, and other relevant factors. In the design and production, we should focus on reducing the resistance value between the most distal of clothing, the parts of contacting electrification equipment and limbs, in order to increase its connectivity; the structural design of clothing should be simplified.

Profile Imaging of Silicon Surface Reconstructions

1985 ◽  
Vol 43 ◽  
pp. 262-263
Author(s):  
O.L. Krivanek ◽  
G.J. Wood
Keyword(s):  
Electron Microscopy ◽  
Surface Structure ◽  
Structure Determination ◽  
Silicon Surface ◽  
Good Resolution ◽  
Surface Reconstructions ◽  
Bulk Structure ◽  
Point To Point ◽  
The Relationship

Electron microscopy at 0.2nm point-to-point resolution, 10-10 torr specimei region vacuum and facilities for in-situ specimen cleaning presents intere; ing possibilities for surface structure determination. Three methods for examining the surfaces are available: reflection (REM), transmission (TEM) and profile imaging. Profile imaging is particularly useful because it giv good resolution perpendicular as well as parallel to the surface, and can therefore be used to determine the relationship between the surface and the bulk structure.

Structural Aspects of Phonological Development

1988 ◽  
Vol 19 (1) ◽  
pp. 5-16 ◽  
Author(s):  
Karen E. Pollock ◽  
Richard G. Schwartz
Keyword(s):  
Clinical Management ◽  
Structural Complexity ◽  
Strong Preference ◽  
Phonological Development ◽  
Structural Position ◽  
Phonological Disorders ◽  
Syllabic Structure ◽  
The Relationship ◽  
Structural Aspects ◽  
Target Words

The relationship between syllabic structure and segmental development was examined longitudinally in a child with a severe phonological disorder. Six speech samples were collected over a 4-year period (3:5 to 7:3). Analyses revealed gradual increases in the complexity and diversity of the syllable structures produced, and positional preferences for sounds within these forms. With a strong preference for [d] and [n] at the beginning of syllables, other consonants appeared first at the end of syllables. Implications for clinical management of phonological disorders include the need to consider both structural position and structural complexity in assessing segmental skills and in choosing target words for intervention.

Respiratory mechanics in mechanically ventilated patients with respiratory failure

1985 ◽  
Vol 58 (6) ◽  
pp. 1849-1858 ◽  
Author(s):  
A. Rossi ◽  
S. B. Gottfried ◽  
B. D. Higgs ◽  
L. Zocchi ◽  
A. Grassino ◽  
...  
Keyword(s):  
Time Constant ◽  
Inflation Rate ◽  
Respiratory Mechanics ◽  
Mechanically Ventilated ◽  
Mechanically Ventilated Patients ◽  
Airway Occlusion ◽  
The Relationship ◽  
Resistance Value ◽  
Ventilated Patients

In 11 mechanically ventilated patients, respiratory mechanics were measured 1) during constant flow inflation and 2) following end-inflation airway occlusion, as proposed in model analysis (J. Appl. Physiol. 58: 1840–1848, 1985. During the latter part of inflation, the relationship between driving pressure and lung volume change was linear, allowing determination of static respiratory elastance (Ers) and resistance (RT). The latter represents in each patient the maximum resistance value that can obtain with the prevailing time constant inhomogeneity. Following occlusion, Ers and RT were also obtained along with RT (min) which represents a minimum, i.e., resistance value that would obtain in the absence of time constant inhomogeneity. A discrepancy between inflation and occlusion Ers and RT was found only in the three patients without positive end-expiratory pressure, and could be attributed to recruitment of lung units during inflation. In all instances Ers and RT were higher than normal. RT(min) was lower in all patients than the corresponding values of RT, indicating that resistance was frequency dependent due to time constant inequalities. Changes in inflation rate did not affect Ers, while RT increased with increasing flow.

scholarly journals Understanding the Relationship Between Crown Shape and Size and Structural Complexity of Individual Trees

2020 ◽  
Author(s):  
Ninni Saarinen ◽  
Kim Calders ◽  
Ville Kankare ◽  
Tuomas Yrttimaa ◽  
Samuli Junttila ◽  
...  
Keyword(s):  
Structural Complexity ◽  
Crown Shape ◽  
Individual Trees ◽  
The Relationship ◽  
Shape And Size

scholarly journals Critical Review of Methods to Estimate PM2.5 Concentrations within Specified Research Region

2018 ◽  
Vol 7 (9) ◽  
pp. 368 ◽  
Author(s):  
Guangyuan Zhang ◽  
Xiaoping Rui ◽  
Yonglei Fan
Keyword(s):  
Particulate Matter ◽  
Critical Review ◽  
Research Interest ◽  
Traditional Methods ◽  
Academic Interest ◽  
Filter Membrane ◽  
Representative Points ◽  
The Relationship

Obtaining PM2.5 data for the entirety of a research region underlies the study of the relationship between PM2.5 and human spatiotemporal activity. A professional sampler with a filter membrane is used to measure accurate values of PM2.5 at single points in space. However, there are numerous PM2.5 sampling and monitoring facilities that rely on data from only representative points, and which cannot measure the data for the whole region of research interest. This provides the motivation for researching the methods of estimation of particulate matter in areas having fewer monitors at a special scale, an approach now attracting considerable academic interest. The aim of this study is to (1) reclassify and particularize the most frequently used approaches for estimating the PM2.5 concentrations covering an entire research region; (2) list improvements to and integrations of traditional methods and their applications; and (3) compare existing approaches to PM2.5 estimation on the basis of accuracy and applicability.

Variability in rainfall information derived from collocated microwave links

2021 ◽  
Author(s):  
Anna Špačková ◽  
Vojtěch Bareš ◽  
Martin Fencl
Keyword(s):  
Electromagnetic Waves ◽  
Rainfall Intensity ◽  
Weather Condition ◽  
Estimation Accuracy ◽  
Response Patterns ◽  
Spatial Coverage ◽  
Telecommunications Network ◽  
Path Lengths ◽  
Point To Point ◽  
The Individual

<p>In the field of hydrology, there is a significant demand for high spatial-temporal resolution of rainfall information that can be met by commercial microwave links (CMLs). CMLs are commonly used as a backhaul of telecommunications network with favourable spatial coverage especially in urbanized areas. CMLs are point-to-point radio connections operating at frequencies where attenuation of electromagnetic waves can be related to the rainfall intensity.</p><p>The ability of CMLs to assess rainfall intensity is determined by hardware parameters and path lengths of CMLs. The CML operates at various frequencies with horizontal or vertical polarization, moreover, link paths have lengths ranging from hundreds of meters up to kilometres. The characteristics of the rainfall needs to be reflected as they have impact on the errors (de Vos et al., 2019). Even collocated CMLs can detect considerably dissimilar rainfall information. To increase effectivity of rainfall information retrieval it is crucial to understand uncertainties arising from diversity of CML characteristics.</p><p>This study evaluates collocated CMLs that are assumed to be affected by the same weather condition. Having identical CML characteristics (as well as the propagations of the signals), it is expected to observe the same response patterns in the attenuated signals. Any disagreement could be caused by random error, sensitivity to the rainfall intensities, and/or hardware reaction to the condition (e.g. sensitivity of the antenna radome to the rainfall splash). Therefore, the role of arrangement of the direction of rainfall field advection and position of the collocated link paths is considered. The magnitude of disagreement between different groups of collocated links could be specified based on their characteristics. Oppositely, for collocated links under the same conditions but with different characteristics, the attributes of the individual CMLs are suspected for the disagreement.</p><p> </p><p>References</p><p>de Vos, L. W., Overeem, A., Leijnse, H., and Uijlenhoet, R. (2019). Rainfall Estimation Accuracy of a Nationwide Instantaneously Sampling Commercial Microwave Link Network: Error Dependency on Known Characteristics. Journal of Atmospheric and Oceanic Technology 36, 7, 1267-1283. https://doi.org/10.1175/JTECH-D-18-0197.1</p><p> </p><p>This study was supported by the project SpraiLINK 20-14151J of the Czech Science Foundation.</p>

Thermodynamics of stressed systems

2005 ◽  
Author(s):  
Boris S. Bokstein ◽  
Mikhail I. Mendelev ◽  
David J. Srolovitz
Keyword(s):  
Mechanical Properties ◽  
Thermodynamic Functions ◽  
School Child ◽  
Displacement Vector ◽  
Mechanical Deformation ◽  
Material Point ◽  
General Description ◽  
The Difference ◽  
Point To Point ◽  
The Relationship

As every school child knows, the difference between a solid and a liquid is that a liquid takes the shape of the container in which it is placed while the shape of a solid is independent of the shape of the container (providing the container is big enough). In other words, we must apply a force in order to change the shape of a solid. However, the thermodynamic functions described heretofore have no terms that depend on shape. In this chapter, we extend the thermodynamics discussed above to include such effects and therefore make it applicable to solids. However, since this is a thermodynamics, rather than a mechanics text, we focus more on the relationship between stress and thermodynamics rather than on a general description of the mechanical properties of solids. We start out discussion of mechanical deformation by describing the change of shape of a solid. We define the displacement vector at any point in the solid u(x, y, z) as the change in location of the material point (x, y, z) upon deformation: that is, ux(x, y, z) = x' - x, where the prime indicates the coordinates of the material that was at the unprimed position prior to the deformation. In linear elasticity, we explicitly assume that the displacement vector varies slowly from point to point within the solid where i and j denote the directions along the three axes, x, y, and z. Consider the small parallel-piped section of a solid with perpendicular edges shown in Fig. 7.1. We label the first corner as O, located at position (xO, yO, zO) and subsequent corners as A, B, . . . located at positions (xA, yA, zA), (xB, yB, zB), . . . The edge lengths are Δx, Δy, and Δz such that, for example, xA = xO + Δx. As a result of the deformation, the material originally at point O is displaced to point O' with coordinates (x'O, y'O, z'O).

A Study on Temperature Properties of Different Types of Fixed Resistor

2017 ◽  
Vol 866 ◽  
pp. 392-397
Author(s):  
Nattapong Phanthuna ◽  
Chaiwat Jassadajin
Keyword(s):  
Low Power ◽  
Temperature Coefficient ◽  
Temperature Variation ◽  
Carbon Film ◽  
Experimental Result ◽  
Experimental Setup ◽  
Different Types ◽  
Wound Type ◽  
The Relationship ◽  
Resistance Value

This paper studies the relationship between the value of temperature variation and the resistance value of each type of general resistors as well as also determines the temperature coefficient value of each resistor type. All obtained results will be compared to build a guideline for selecting the resistor to apply in any applications accurately and properly. Each type of 1 k-ohm resistor that has different power is used to study its properties and is controlled its temperature variation to be in range of 20 to 30 degree Celsius. An experimental setup to control the temperature variation of the resistors in this paper is that the resistors are put into an oil bath controlled its temperature after that measuring the changed resistance value of the resistors following oil temperature in the bath. The experimental result demonstrates that the temperature variation affects to change the resistance value of Carbon Film type the most but affects to change the resistance value of Wire Wound type with low power the least.

scholarly journals The Relationship Between Gas and Cirrus Dust Filaments at the Edge of the Expanding Shell in Eridanus

1990 ◽  
Vol 139 ◽  
pp. 235-236
Author(s):  
G. L. Verschuur ◽  
F. Verter ◽  
L. J. Rickard ◽  
D. T. Leisawitz
Keyword(s):  
High Resolution ◽  
Surface Brightness ◽  
Neutral Hydrogen ◽  
Scale Structure ◽  
Small Scale ◽  
Molecular Gas ◽  
Small Scale Structure ◽  
Point To Point ◽  
The Relationship ◽  
Co Observations

At the boundary of a large expanding shell in Eridanus around l = 187°, b = −50° the morphology observed in the HI emission is well mimicked by the 100 μm surface brightness but with associated structures offset by as much as 0.°5. A point-to-point comparison between I100μm and NHI in filaments of neutral hydrogen and dust (IR cirrus) produces only a weak dependence. However, when I100μm at a cirrus dust peak is compared with NHI at the associated H i peak, a relationship closer to that reported by other workers is found. Preliminary CO observations have set low limits on the molecular gas in these filaments. Since the H i and dust in our region are associated with a large expanding shell (or superbubble), shocks may be responsible for separation of gas and dust. The existence of small-scale structure in both the HI and IR is noted. We conclude that attempts to correlate HI and IR must invoke high-resolution area surveys.

Cutting resistance of flexible armour using multiple layers of triaxial kevlar fabric

2020 ◽  
pp. 152808372096827
Author(s):  
Magdi El Messiry ◽  
Shaimaa Youssef El-Tarfawy
Keyword(s):  
Cutting Force ◽  
Areal Density ◽  
Resistance Force ◽  
Knitted Fabric ◽  
Cutting Resistance ◽  
First Case ◽  
Weft Knitted Fabric ◽  
Cut Resistance ◽  
The Relationship ◽  
Resistance Value

The textiles capable of cutting resistance found applications in the industrial and military areas to construct flexible lightweight soft body armors. In the present work, a theoretical model to understand the mechanism of fabric cut resistance in a different direction for weft-knitted, triaxial, and multiple layers structures. An experimental study of cutting resistance force was done on weft-knitted fabric with Kevlar 29 triaxial fabrics in multiple layers structure to support derived mathematical model for the effect of multiple layers structure on their cutting force. The study examines specific cut resistance of the structure from four layers of Kevlar triaxial fabrics covered with knitted fabric on both sides. The angle of cutting force varied from 0°, 60°, and 90° with respect to the yarn inclination. Results show that the cutting force of the multilayer structure is linearly proportional to the number of Kevlar triaxial fabrics layers. The specific cut resistance value of the structure from four layers of Kevlar triaxial fabrics, covered with knitted fabric on both sides, reached 544, 435, and 326 (N/g/cm2) for cutting directions: angled 60°, vertical, and horizontal, respectively. In this work, the comparison between the triaxial fabric of high areal density and multiple layers of triaxial fabric with resultant same areal density indicates that a better specific cutting force was achieved in the first case. Furthermore, it investigated the relationship between triaxial surface density, the direction of cutting, and the number of triaxial fabric layers and discussed the optimum specific properties of the different structures.

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