scholarly journals APPLICATION RANGE OF TWO-MODE BASED STATIC SEISMIC LOAD FOR SINGLE LAYER RETICULATED SHELLS

2021 ◽  
Vol 86 (790) ◽  
pp. 1644-1654
Author(s):  
Yuji TAKIUCHI ◽  
Shoji NAKAZAWA ◽  
Yuki HIGASHIYAMA ◽  
Shiro KATO
Keyword(s):  
Single Layer ◽  
Seismic Load ◽  
Application Range

Comparison of seismic responses of a reticulated dome under stochastic uniform and spatially correlated and coherent multiple-support excitation for a scenario seismic event

2020 ◽  
Vol 35 (4) ◽  
pp. 113-125
Author(s):  
YG Li ◽  
TJ Liu ◽  
F Fan ◽  
HP Hong
Keyword(s):  
Spatial Correlation ◽  
Seismic Event ◽  
Amplitude Spectrum ◽  
Spatial Coherence ◽  
Single Layer ◽  
Seismic Load ◽  
Seismic Responses ◽  
Spatially Correlated ◽  
Multiple Support ◽  
Support Excitation

Structures with multiple supports can be sensitive to spatial coherence and spatial correlation. Since the historical recordings are insufficient for selecting records that match predefined inter-support distances of a structure, desired seismic magnitude (or intensity) and site to seismic source distance for structural analysis, such records need to be simulated. In this study, we use a procedure that is extended based on the stochastic point-source method to simulate records for scenario events. The application of the simulated records to a single-layer reticulated dome with multiple supports is presented. The application is aimed at investigating the differences between the responses subjected to spatially uniform excitation and to spatially correlated and coherent multiple-support excitation for a scenario seismic event, assessing the relative importance of the spatial coherence and spatial correlation on the responses, and evaluating the effect of the uncertainty in the spatially correlated and coherent records for a scenario event on the statistics of the seismic responses. The analysis results indicate that the spatial correlation of the Fourier amplitude spectrum has a predominant influence on the linear/nonlinear responses, and the consideration of spatially correlated and coherent excitation at multiple supports is very important. The consideration of uniform excitation severely underestimates the seismic load effects as compared to those obtained under spatially correlated and coherent multiple-support excitation.

Vertical and Horizontal Seismic Response Analyses of Long-Span and Single-Layer Spherical Lattice Shell Structure

2014 ◽  
Vol 602-605 ◽  
pp. 602-605
Author(s):  
Jin Sheng He ◽  
She Liang Wang
Keyword(s):  
Vibration Control ◽  
Shell Structure ◽  
Response Spectrum ◽  
Single Layer ◽  
Internal Force ◽  
Seismic Load ◽  
Seismic Responses ◽  
Long Span ◽  
Current Design ◽  
Lattice Shell

The dynamic characteristics of 80 m single-layer spherical lattice shell structure are analyzed to control its vibration under seismic load. Through the response spectrum curve of current design specification, the analyses for the vertical and horizontal seismic responses of the single-layer spherical lattice shell structure are made by CQC, and the displacement response of the nodes and internal force of the rods unit are calculated respectively. The calculation results show that the vertical and horizontal seismic responses of the long-span lattice shell structure are in great difference, and should be performed in vibration control at the same time, which could provide certain references for the seismic design and vibration control of single-layer spherical lattice shell structure.

scholarly journals BUCKLING STRENGTH OF SINGLE LAYER LATTICE DOMES UNDER STATIC SEISMIC LOAD

2014 ◽  
Vol 79 (704) ◽  
pp. 1523-1533 ◽  
Author(s):  
Toshiyuki OGAWA ◽  
Kousuke YAMAOKA ◽  
Ken'ichi MINOWA ◽  
Toru TAKEUCHI
Keyword(s):  
Single Layer ◽  
Seismic Load ◽  
Buckling Strength

Dynamic Stability Analysis of K8 Single-Layer Latticed Shell Structures Suffered from Earthquakes

2011 ◽  
Vol 94-96 ◽  
pp. 52-56
Author(s):  
Wen Feng Du ◽  
Fu Dong Yu ◽  
Zhi Yong Zhou
Keyword(s):  
Stability Analysis ◽  
Dynamic Stability ◽  
Dynamic Instability ◽  
Single Layer ◽  
Dynamic Responses ◽  
Shell Structures ◽  
Seismic Load ◽  
The Finite Element Method ◽  
The Third ◽  
Peak Value

Aiming at the dynamic stability of the K8 single-layer latticed shell structures, it was carried out the dynamic stability analysis based on the finite element method(FEM) in this paper. The dynamic responses of the structure are calculated using the FEM and the B-R rule is applied to determine the dynamic instability critical loads. Results show that the dynamic instability is prone to take place in the K8 single-layer latticed shell structures under the severe seismic load and the dynamic instability critical seismic wave peak value is about 0.7g. The location of instability starts from the intersection between the third circular members and the radial members, then it spreads abroad until the structure collapses.

scholarly journals Design and Evaluation of a Multidirectional Thermal Flow Sensor on Flexible Substrate

2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Dimitris Barmpakos ◽  
Ioannis Th. Famelis ◽  
Anastasios Moschos ◽  
Damianos Marinatos ◽  
Grigoris Kaltsas
Keyword(s):  
Estimation Error ◽  
Flexible Substrate ◽  
Back Propagation ◽  
Single Layer ◽  
Protective Layer ◽  
Flow Sensor ◽  
Training Procedure ◽  
Thermal Flow ◽  
Application Range ◽  
Thermal Flow Sensor

The development and the corresponding evaluation of a multidirectional thermal flow sensor are presented in this work. The sensor was fabricated on a flexible substrate, allowing for new applications, since it provides the possibility of installation in nonplanar surfaces such as pipelines. Furthermore, the sensing elements are not in direct contact with the fluid, which increases the device reliability, extends its application range, and allows the noncontact monitoring of fluids. This was achieved by utilizing the substrate as a protective layer between the sensing elements and the fluid under measurement. The operation principle is based on the determination of the flow-induced temperature profile variations. A dedicated experimental setup was designed and used for the device evaluation. Both flow velocity value and direction were successfully extracted, while the results were consistent with the predicted theoretical values. A single-layer back propagation neural network that correlates the sensors’ readouts to the angle of rotation was implemented, which leads to a mean absolute direction estimation error in the order of 2.7 degrees independent to the training procedure datasets.

Crystalline order to a resolution of 4.7 A in the sheath of Methanospirilium hungatii: A cross-beta structure

1984 ◽  
Vol 42 ◽  
pp. 214-215
Author(s):  
Murray Stewart ◽  
T.J. Beveridge ◽  
D. Sprott
Keyword(s):  
Cell Wall ◽  
Single Layer ◽  
Uranyl Acetate ◽  
Optical Diffraction ◽  
Tube Axis ◽  
Basic Subunit ◽  
Beta Structure ◽  
Diffraction Patterns ◽  
Protein Treatment ◽  
General Appearance

The archaebacterium Methanospirillum hungatii has a sheath as part of its cell wall which is composed mainly of protein. Treatment with dithiothreitol or NaOH released the intact sheaths and electron micrographs of this material negatively stained with uranyl acetate showed flattened hollow tubes, about 0.5 μm diameter and several microns long, in which the patterns from the top and bottom were superimposed. Single layers, derived from broken tubes, were also seen and were more simply analysed. Figure 1 shows the general appearance of a single layer. There was a faint axial periodicity at 28.5 A, which was stronger at irregular multiples of 28.5 A (3 and 4 times were most common), and fine striations were also seen at about 3° to the tube axis. Low angle electron diffraction patterns (not shown) and optical diffraction patterns (Fig. 2) from these layers showed a complex meridian (as a result of the irregular nature of the repeat along the tube axis) which showed a clear maximum at 28.5 A, consistent with the basic subunit spacing.

Differentiation Processes of the Ocellar Retina of the Honeybee (Apis Mellifera L.)

1990 ◽  
Vol 48 (3) ◽  
pp. 430-431
Author(s):  
Maria Anna Pabst
Keyword(s):  
Apis Mellifera ◽  
Distal Part ◽  
Cell Layer ◽  
Single Layer ◽  
Photoreceptor Cells ◽  
Distal Segment ◽  
Compound Eyes ◽  
Thin Sections ◽  
Ultrastructural Studies ◽  
Adult Worker

In addition to the compound eyes, honeybees have three dorsal ocelli on the vertex of the head. Each ocellus has about 800 elongated photoreceptor cells. They are paired and the distal segment of each pair bears densely packed microvilli forming together a platelike fused rhabdom. Beneath a common cuticular lens a single layer of corneagenous cells is present.Ultrastructural studies were made of the retina of praepupae, different pupal stages and adult worker bees by thin sections and freeze-etch preparations. In praepupae the ocellar anlage consists of a conical group of epidermal cells that differentiate to photoreceptor cells, glial cells and corneagenous cells. Some photoreceptor cells are already paired and show disarrayed microvilli with circularly ordered filaments inside. In ocelli of 2-day-old pupae, when a retinogenous and a lentinogenous cell layer can be clearly distinguished, cell membranes of the distal part of two photoreceptor cells begin to interdigitate with each other and so start to form the definitive microvilli. At the beginning the microvilli often occupy the whole width of the developing rhabdom (Fig. 1).

Characterization of a monolayer graphitic structure

1994 ◽  
Vol 52 ◽  
pp. 760-761
Author(s):  
X. Lin ◽  
X. K. Wang ◽  
V. P. Dravid ◽  
J. B. Ketterson ◽  
R. P. H. Chang
Keyword(s):  
Three Dimensional ◽  
Single Layer ◽  
Synthesis Process ◽  
Graphitic Structure ◽  
Positive Gaussian Curvature ◽  
Graphitic Sheet ◽  
Structural And Electronic Properties ◽  
New Material ◽  
Hexagonal Network

For small curvatures of a graphitic sheet, carbon atoms can maintain their preferred sp2 bonding while allowing the sheet to have various three-dimensional geometries, which may have exotic structural and electronic properties. In addition the fivefold rings will lead to a positive Gaussian curvature in the hexagonal network, and the sevenfold rings cause a negative one. By combining these sevenfold and fivefold rings with sixfold rings, it is possible to construct complicated carbon sp2 networks. Because it is much easier to introduce pentagons and heptagons into the single-layer hexagonal network than into the multilayer network, the complicated morphologies would be more common in the single-layer graphite structures. In this contribution, we report the observation and characterization of a new material of monolayer graphitic structure by electron diffraction, HREM, EELS.The synthesis process used in this study is reported early. We utilized a composite anode of graphite and copper for arc evaporation in helium.

The Continuous Single-Layer Anastomosis in the Gastrointestinal Tract

Swiss Surgery ◽  
2003 ◽  
Vol 9 (3) ◽  
pp. 114-120 ◽  
Author(s):  
Steinke ◽  
Leippold ◽  
Schweizer
Keyword(s):  
Gastrointestinal Tract ◽  
Single Layer

Über die Frage der besten oder "richtigen" Technik bei gastrointestinalen Anastomosen wird seit je diskutiert. Die Ansprüche an eine gute Anastomosentechnik sind: Gute Durchblutung, Wasserdichtigkeit, Spannungsfreiheit, Sicherheit, leichte Durchführbarkeit, wenig Unruhe und Verschmutzung im Operationsgebiet und geringe Kosten. Die Operationstechnik der extramukösen, fortlaufenden Anastomosentechnik im Gastrointestinaltrakt wird in Wort und Bild erläutert. Anhand einer Pilotstudie, einer randomisierten Vergleichsstudie, einer Schweizer Multizenterstudie und schliesslich einer 5-jährigen Qualitätskontrollstudie wird gezeigt, dass diese "Schweizer"-Technik allen Anforderungen zur Durchführung einer "idealen" Anastomose gerecht wird und an fast allen intestinalen Lokalisationen verwendet werden kann.

Technical textiles for protection against Arc-flash fire: Savesplash®

2020 ◽  
pp. 67-78
Author(s):  
Nandan Kumar ◽  
Sainath Shrikant Pawaskar
Keyword(s):  
Attenuation Factor ◽  
Threshold Energy ◽  
Single Layer ◽  
Weather Conditions ◽  
Electric Arc ◽  
Risk Category ◽  
Technical Textiles ◽  
Flash Fire ◽  
Level 3 ◽  
Arc Flash

Flash fire caused by electric arc is different than that caused by flammable liquids/fumes or combustible dusts. A suitable protective clothing for protection against electric arc-flash must be designed as per Indian weather conditions. Currently available garments are manufactured using two or three layers of woven/nonwoven combinations to achieve higher Hazard Risk Category (HRC) rating (level 3 and above). However, they are heavy and not comfortable to the end users. Savesplash® is a single layer inherent flame-retardant knitted fabric. Its arc rating was determined using ASTM standards. It achieved arc thermal performance value (ATPV) of 41 cal/cm2, breakopen threshold energy (E_BT) of 42 cal/cm2 and heat attenuation factor (HAF) of 94% when tested as per ASTM F1959/F1959M-14 which translated into an arc rating of 41 cal/cm2. This is equivalent to HRC level 4 ratings as per National Fire Protection Association’s NFPA 70E standard (USA). Further, cut and sewn gloves (HM-100) developed using Savesplash® fabric reinforced with leather on palm area achieved ATPV of 63 cal/cm2 and HAF of 94.5% when tested as per ASTM F2675/F2675M-13.

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