Single-chorded Plane Space Trusses

A discussion is presented of the mechanics of the plate-like behaviour of certain space trusses that possess a single layer of chords. The web systems are formed out of the chord plane, and consideration is given to web systems that are placed on one or both sides of the chord plane. It is recognized that a torsional mode of behaviour is utilized for the double-layer web system for carrying transverse load. A combination of flexural and torsional modes is utilized for the single-layer system.

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Characteristics of Oceanic Warm Cloud Layers within Multilevel Cloud Systems Derived by Satellite Measurements

Atmosphere ◽

10.3390/atmos10080465 ◽

2019 ◽

Vol 10 (8) ◽

pp. 465 ◽

Cited By ~ 1

Author(s):

Yuhao Ding ◽

Qi Liu ◽

Ping Lao

Keyword(s):

Double Layer ◽

Lower Layer ◽

Single Layer ◽

Distribution Patterns ◽

Radar Data ◽

Multilayered Structures ◽

Layer System ◽

Cloud Systems ◽

Warm Cloud ◽

Double Layer System

Low-level warm clouds are a major component in multilayered cloud systems and they are generally hidden from the top-down view of satellites with passive measurements. This study conducts an investigation on oceanic warm clouds embedded in multilayered structures by using spaceborne radar data with fine vertical resolution. The occurrences of warm cloud overlapping and the geometric features of several kinds of warm cloud layers are examined. It is found that there are three main types of cloud systems that involve warm cloud layers, including warm single layer clouds, cold-warm double layer clouds, and warm-warm double layer clouds. The two types of double layer clouds account for 23% and in the double layer occurrences warm-warm double layer subsets contribute about 13%. The global distribution patterns of these three types differ from each other. Single-layer warm clouds and the lower warm clouds in the cold-warm double layer system they have nearly identical geometric parameters, while the upper and lower layer warm clouds in the warm-warm double layer system are distinct from the previous two forms of warm cloud layers. In contrast to the independence of the two cloud layers in cold-warm double layer system, the two kinds of warm cloud layers in the warm-warm double layer system may be coupled. The distance between the two layers in the warm-warm double layer system is weakly dependent on cloud thickness. Given the upper and lower cloud layer with moderate thickness of around 1 km, the cloudless gap reaches its maximum when exceeding 600 m. The cloudless gap decreases in thickness as the two cloud layers become even thinner or thicker.

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An Architecture of a Two-Layer Cloud-Based Web System Using a Fuzzy-Neural Request Distribution

Vietnam Journal of Computer Science ◽

10.1142/s2196888820500141 ◽

2020 ◽

Vol 07 (03) ◽

pp. 251-262

Author(s):

Krzysztof Zatwarnicki ◽

Anna Zatwarnicka

Keyword(s):

Information Systems ◽

Double Layer ◽

Human Activity ◽

Cloud Systems ◽

Distribution Strategy ◽

Request Distribution ◽

Fuzzy Neural ◽

The Web ◽

Layer Cloud ◽

Web Systems

Nowadays, a significant part of human activity is supported by information systems, especially Web systems, hosted in the Web clouds. The architectures of Web cloud systems are in most cases complex. In this paper, we try to determine which cloud configuration in double-layer architecture is the best when using the fuzzy-neural intelligent method of request distribution. We present the distribution strategy, a testbed and the results of the conducted experiments. At the end of this paper, we discuss results and present final conclusions.

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Oceanic warm cloud layers within multilevel cloud systems observed by satellite measurements

10.5194/egusphere-egu2020-6311 ◽

2020 ◽

Author(s):

Qi Liu ◽

Yuhao Ding ◽

Ping Lao

Keyword(s):

Double Layer ◽

Radiative Forcing ◽

Lower Layer ◽

Numerical Models ◽

Three Dimensional ◽

Single Layer ◽

Layer System ◽

Cloud Systems ◽

Warm Cloud ◽

Double Layer System

<p>Low-level warm clouds are a major component in multilayered cloud systems and are generally hidden from the top-down view of satellites with passive measurements. By using spaceborne radar data with fine vertical resolution, this study conducts an investigation on oceanic warm clouds embedded in multilayered structures. The occurrences of warm cloud overlapping and the geometric features of several kinds of warm cloud layers are examined. It is found that there are three main types of cloud systems that involve warm cloud layers, including warm single layer clouds, cold-warm double layer clouds and warm-warm double layer clouds. The two types of double layer clouds account for 23% and in the double layer occurrences warm-warm double layer subsets contribute about 13%. The global distribution patterns of these three types differ from each other. Single-layer warm clouds and the lower warm clouds in the cold-warm double layer system have nearly identical geometric parameters, while the upper and lower layer warm clouds in the warm-warm double layer system are distinct from the previous two forms of warm cloud layers. In contrast to the independence of the two cloud layers in cold-warm double layer system, the two kinds of warm cloud layers in the warm-warm double layer system may be coupled. The distance between the two layers in the warm-warm double layer system is weakly dependent on cloud thickness. Given the upper and lower cloud layer with moderate thickness around 1 km, the cloudless gap reaches its maximum exceeding 600 m. As the two cloud layers become even thinner or thicker, the cloudless gap decreases in thickness. It is believed that such knowledge on cloud overlapping is critical for fully understanding the distribution of warm clouds in three-dimensional space. The results derived in this study could help validating cloud results of numerical models, which are indeed three-dimensional in nature. They could also be used to improve the estimation of cloud radiative forcing, since it is affected by cloud occurrences and especially their vertical structures. It should be pointed out that solid explanations for the above cloud features cannot be presented by only using these satellite data themselves.&#160;</p>

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Evaluating the Usability of Emergency Fund Target Web System among Young Adults

Journal of Computing Research and Innovation ◽

10.24191/jcrinn.v2i4.60 ◽

2018 ◽

Vol 2 (4) ◽

pp. 28-32

Author(s):

Izzatie Zakaria ◽

Nor Azzyati Hashim

Keyword(s):

Young Adults ◽

Financial Management ◽

Job Loss ◽

Usability Testing ◽

Ease Of Use ◽

Web System ◽

Emergency Fund ◽

The Web ◽

Web Systems

Young adults need to know the importance of having a good financial management to prevent the engagement in extensive debt. One of the ways is by having saving for emergency fund. Emergency fund is vital as it can be used during any unwanted events such as job loss, health emergency and other unexpected expenses. Most existing web systems for personal financial management are more towards budgeting and tracking e xpenditures. Thus, to encourage people especially young adults to build emergency fund, a web system called Emergency Fund Target (EFT) was developed. This paper investigates the ease - of - use and benefits of EFT web system among young adults. Evaluation for this web system using usability testing involved 15 young adults who already being employed. From the findings, it is discovered that EFT system is easy to use and enables users to learn about emergency fund in order to use the system to keep track their saving for emergency fund. For the future works o f EFT, the web system will enhance to advice users who has completed the emergency fund saving on moving into investment for short, medium and long term financial goals.

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Dynamic Countermeasure Fabrics for Post-Spaceflight Orthostatic Intolerance

Aerospace Medicine and Human Performance ◽

10.3357/amhp.5560.2020 ◽

2020 ◽

Vol 91 (6) ◽

pp. 525-531 ◽

Cited By ~ 1

Author(s):

Rachael M. Granberry ◽

Kevin P. Eschen ◽

Amy J. Ross ◽

Julianna M. Abel ◽

Bradley T. Holschuh

Keyword(s):

Double Layer ◽

High Performance ◽

Orthostatic Intolerance ◽

Dynamic Compression ◽

Single Layer ◽

Design Parameters ◽

Layer System ◽

Compression Garments ◽

Air Supply ◽

Low Profile

INTRODUCTION: Aerospace orthostatic intolerance garments (OIG) have historically been pneumatic (e.g., NASA’s antigravity suit), an approach that inhibits mobility and requires connection to an air supply. Elastic compression garments, an alternative technology, are difficult to don/doff and cannot be worn in a noncompressive state, resulting in discomfort and usability challenges. This research evaluates a novel technology—contractile shape memory alloy (SMA) knitted actuators—that can enable low-profile, dynamic compression for an aerospace OIG.METHODS: To characterize the functional capabilities of SMA knitted actuators, displacement control testing was conducted on 10 actuator samples with a range of geometric design parameters. Inactive (FI) and actuated forces (FA) were observed by repeatedly thermally cycling each sample at 0%, 15%, 30%, and 45% structural strain. Compression capabilities were approximated using medical compression hosiery standards and anthropometric data from a representative aerospace population (ANSUR 2012).RESULTS: Dynamic compression predictions reached 52 mmHg (single layer fabric) and 105 mmHg (double layer fabric) at the ankle. Low, inactive pressures (p < 20 mmHg) demonstrate that compression is controllable and can be dynamically increased upon actuation up to 33 mmHg in a single layer system and up to 67 mmHg in a double layer system.DISCUSSION: The results highlight the potential of SMA knitted actuators to enable low-profile, dynamic compression garments that can reach medically therapeutic pressures on an aerospace population to counteract OI symptoms. In addition to astronautic applications, this technology demonstrates widespread terrestrial medical and high-performance aircraft applicability.Granberry RM, Eschen KP, Ross AJ, Abel JM, Holschuh BT. Dynamic countermeasure fabrics for post-spaceflight orthostatic intolerance. Aerosp Med Hum Perform. 2020; 91(6):525–531.

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Discrete element method to model cracking for two layer systems

TAPPI Journal ◽

10.32964/tj18.2.101 ◽

2019 ◽

Vol 18 (2) ◽

pp. 101-108

Author(s):

Daniel Varney ◽

Douglas Bousfield

Keyword(s):

Discrete Element Method ◽

Flexural Modulus ◽

Single Layer ◽

Discrete Element ◽

Flexural Stress ◽

Layer System ◽

Three Point Bending ◽

Moving Force ◽

Coating Layers ◽

Element Method

Cracking at the fold is a serious issue for many grades of coated paper and coated board. Some recent work has suggested methods to minimize this problem by using two or more coating layers of different properties. A discrete element method (DEM) has been used to model deformation events for single layer coating systems such as in-plain and out-of-plain tension, three-point bending, and a novel moving force picking simulation, but nothing has been reported related to multiple coating layers. In this paper, a DEM model has been expanded to predict the three-point bending response of a two-layer system. The main factors evaluated include the use of different binder systems in each layer and the ratio of the bottom and top layer weights. As in the past, the properties of the binder and the binder concentration are input parameters. The model can predict crack formation that is a function of these two sets of factors. In addition, the model can predict the flexural modulus, the maximum flexural stress, and the strain-at-failure. The predictions are qualitatively compared with experimental results reported in the literature.

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Cracking at the fold in double layer coated paper: the influence of latex and starch composition

TAPPI Journal ◽

10.32964/tj18.2.93 ◽

2019 ◽

Vol 18 (2) ◽

pp. 93-99

Author(s):

SEYYED MOHAMMAD HASHEMI NAJAFI ◽

DOUGLAS BOUSFIELD, ◽

MEHDI TAJVIDI

Keyword(s):

Mechanical Properties ◽

Double Layer ◽

Starch Content ◽

Single Layer ◽

Double Layers ◽

Coated Paper ◽

Coated Papers ◽

Coating Layers ◽

Scanned Images ◽

Packaging Paper

Cracking at the fold of publication and packaging paper grades is a serious problem that can lead to rejection of product. Recent work has revealed some basic mechanisms and the influence of various parameters on the extent of crack area, but no studies are reported using coating layers with known mechanical properties, especially for double-coated systems. In this study, coating layers with different and known mechanical properties were used to characterize crack formation during folding. The coating formulations were applied on two different basis weight papers, and the coated papers were folded. The binder systems in these formulations were different combinations of a styrene-butadiene latex and mixtures of latex and starch for two different pigment volume concentrations (PVC). Both types of papers were coated with single and double layers. The folded area was scanned with a high-resolution scanner while the samples were kept at their folded angle. The scanned images were analyzed within a constant area. The crack areas were reported for different types of papers, binder system and PVC values. As PVC, starch content, and paper basis weight increased, the crack area increased. Double layer coated papers with high PVC and high starch content at the top layer had more cracks in comparison with a single layer coated paper, but when the PVC of the top layer was low, cracking area decreased. No measurable cracking was observed when the top layer was formulated with a 100% latex layer.

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