Smart Impact Management Devices: Experimental Validation of Crush Response of Rapidly Expanded Aluminum Honeycomb

Transportation ◽

10.1115/imece2006-13069 ◽

2006 ◽

Author(s):

Alan L. Browne ◽

Nancy L. Johnson ◽

Scott R. Webb

Keyword(s):

Energy Management ◽

Impact Energy ◽

Small Volume ◽

Empty Space ◽

Transportation Industry ◽

Test Program ◽

Passive Devices ◽

Aluminum Honeycomb ◽

Pass Through ◽

The Many

A major limitation of current dedicated impact energy management structures and passive devices used in the transportation industry is that their starting volume is their maximum volume, i.e. they dissipate energy by crushing or stroking from a larger to a smaller volume. Since they occupy their maximum volumes in their uncrushed-as-installed state they occupy space that is then only functional in an impact and is otherwise wasted. This limitation has led to the proposal of a class of "smart" impact energy management devices, based on unexpanded aluminum honeycomb (HOBE), that initially occupy a small volume and based on sensor input are rapidly expanded to a much larger crushable volume (nominally 75 times greater) just prior to or in response to an impact. Energy management devices based on this technology, should this technology successfully pass through the many steps needed to prove its viability, would thus allow empty space to be left adjacent to them for operational clearances, serviceability and repair functions, etc. which spaces would yet be fully utilized, due to the expansion of the device, for impact energy management. This paper documents the second portion of an experimental exploration of the viability of this technology. The specific goal of the here-in documented portion of the test program was the demonstration that the crush response of the rapidly expanded honeycomb is comparable to that of the standard pre-expanded commercial product.

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Thermoplastic Pultrusion: A Review

Polymers ◽

10.3390/polym13020180 ◽

2021 ◽

Vol 13 (2) ◽

pp. 180

Author(s):

Kirill Minchenkov ◽

Alexander Vedernikov ◽

Alexander Safonov ◽

Iskander Akhatov

Keyword(s):

Composite Structures ◽

Raw Materials ◽

Thermoplastic Composites ◽

Future Research ◽

Transportation Industry ◽

Architectural Engineering ◽

Simulation Techniques ◽

New Perspective ◽

The Many ◽

Lower Production

Pultrusion is one of the most efficient methods of producing polymer composite structures with a constant cross-section. Pultruded profiles are widely used in bridge construction, transportation industry, energy sector, and civil and architectural engineering. However, in spite of the many advantages thermoplastic composites have over the thermoset ones, the thermoplastic pultrusion market demonstrates significantly lower production volumes as compared to those of the thermoset one. Examining the thermoplastic pultrusion processes, raw materials, mechanical properties of thermoplastic composites, process simulation techniques, patents, and applications of thermoplastic pultrusion, this overview aims to analyze the existing gap between thermoset and thermoplastic pultrusions in order to promote the development of the latter one. Therefore, observing thermoplastic pultrusion from a new perspective, we intend to identify current shortcomings and issues, and to propose future research and application directions.

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Canadian ports-external challenges and reform

Canadian Journal of Civil Engineering ◽

10.1139/l99-053 ◽

1999 ◽

Vol 26 (6) ◽

pp. 818-826 ◽

Cited By ~ 1

Author(s):

Michael C Ircha ◽

Jeff Wood

Keyword(s):

Transportation Network ◽

Marine Policy ◽

Reform Process ◽

Surface Mode ◽

Transportation Industry ◽

Border Trade ◽

Challenges And Opportunities ◽

International Trading ◽

The Many ◽

Tariff Reductions

The federal ports system in Canada faces considerable challenges and opportunities from the rapidly changing international trading environment in which they operate. Global trade has grown as a result of tariff reductions and removal of non-tariff barriers emanating from successive rounds of GATT trade discussions. Ports in Canada and the U.S. have been pressured to improve productivity to handle increasing amounts of cargo in a timely manner. Trans-border trade continues to grow due to the FTA and subsequent NAFTA. However, most continental trade is transported by surface mode to the detriment of ports and the coastal trade in both countries. Improvements to transport technology and economic deregulation challenge ports due to the growth of an integrated intermodal system serving a continental transportation network. Such integrated intermodalism enables the diversion of containerized cargo through load-centre ports in both countries. The many challenges facing Canadian ports are partly driving the current port reform process. Steps have been taken over the past several years to involve the Canadian transportation industry in the development of a national marine policy. The Canada Marine Act, which recently was given royal assent, shifts major commercial ports towards a more businesslike setting. However, this may not be enough, as ports need to be freed from the strictures of the federal government to operate independently in a continental competitive transportation environment.Key words: ports, international trade, shipping, technology, deregulation, reform.

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Impact Performance of Magnetorheological Fluids

Aerospace ◽

10.1115/imece2004-60542 ◽

2004 ◽

Cited By ~ 2

Author(s):

Alan L. Browne ◽

Joseph D. McCleary ◽

Chandra S. Namuduri ◽

Scott R. Webb

Keyword(s):

Magnetic Field ◽

Energy Management ◽

Impact Energy ◽

Applied Magnetic Field ◽

Shock Absorber ◽

Fundamental Property ◽

Free Flight ◽

Impact Performance ◽

Key Issues ◽

Vehicular Crashes

As part of an emerging effort in what is now termed the area of mechamatronics [1], an effort was begun to assess the suitability of MR (magnetorheological) material based devices for impact energy management applications. A fundamental property of MR materials is that their yield stress alters almost instantaneously (and proportionally) to changes in the strength of an applied magnetic field. Based on this property, MR based devices, if found suitable, would be desirable for impact energy management applications because of attendant response tailorability. However, it was identified that prior to adopting MR based devices for impact energy management applications several key issues needed to be addressed. The present study focused on one of the most significant of these, the verification of the tunability of the response of such devices at stroking velocities representative of vehicular crashes. Impact tests using a free-flight drop tower facility were conducted on an MR based energy absorber (shock absorber) for a range of impact velocities and magnetic field strengths. Results demonstrated that over the range of impact velocities tested — 1.0 to 10 m/s — the stroking force/energy absorption exhibited by the device remained dependent on and thus could be modified by changes in the strength of the applied magnetic field.

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Luteinizing hormone-releasing factor: Partial purification

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1965.208.6.1286 ◽

1965 ◽

Vol 208 (6) ◽

pp. 1286-1290 ◽

Cited By ~ 4

Author(s):

M. B. Nikitovitch-Winer ◽

A. H. Pribble ◽

A. D. Winer

Keyword(s):

Luteinizing Hormone ◽

Small Volume ◽

Ammonium Acetate ◽

Solvent System ◽

The Other ◽

Partial Purification ◽

Heat Stable ◽

Small Polypeptide ◽

Pass Through ◽

Acidic Peptides

A method has been devised for the partial purification of luteinizing hormone-releasing factor (LHRF) from extracts of ovine median-eminence tissue. Acid extracts are boiled for 20 min, dialyzed against water for 12 hr, and the dialysate lyophilized. The lyophilized residue is dissolved in a small volume of 5 x 10–3 m ammonium acetate, pH 4.6, and chromatographed on carboxymethylcellulose with an ammonium acetate gradient to 1.0 m, pH 4.6. Several acidic peptides pass through the column rapidly; a peptide with LHRF activity appears in the effluent at about 0.4 m ammonium acetate. The ability of various fractions to induce ovulation on intrapituitary infusion into "atropine-pentobarbital-blocked" proestrous rats was used as the biological test for the release of LH. It was found that, following the infusion of the LHRF-containing fraction, 42 of 54 animals ovulated, while no ovulation was observed in 64 animals treated with any of the other fractions. The LHRF material is probably a small polypeptide which is dialyzable, heat stable, has little absorbancy at either 260 or 280 mµ, and does not give a positive reaction with ninhydrin after paper chromatography in the solvent system used. Evidence is presented that the partially purified LHRF is devoid of LH contamination.

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Dynamic Fracture Analysis of Aluminum Honeycomb Sandwich Panel

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.306-308.67 ◽

2006 ◽

Vol 306-308 ◽

pp. 67-72 ◽

Cited By ~ 1

Author(s):

Byung Il Kim ◽

Byeong Wook Noh ◽

Young Woo Choi ◽

Sung In Bae ◽

Jung I. Song

Keyword(s):

Impact Energy ◽

Sandwich Panel ◽

Bending Test ◽

Face Sheet ◽

Impact Behavior ◽

Lower Face ◽

Short Edge ◽

Edge Direction ◽

Aluminum Honeycomb ◽

The Impact

Impact behaviors of Aluminum Honeycombs Sandwich Panel (AHSP) by drop weight test were investigated in this study. Two types of specimens with l/2" and l/4" cell size were tested by two impactors with the weight of 5.25kgf and 11.9kgf respectively. Transient, contact and elastic-plastic analyses were performed by finite element method. Impact behavior of AHSP about impact sites appeared nearly the same in low impact energy, but it was different in high impact energy. Face was the strongest about impact and short-edge was the weakest. The damaged area of AHSP was enlarged with the increase of impactor weight that is corresponding to impact energy. After 3-point bending test, fracture modes of AHSP were analyzed with AE counts, lower face sheet was fractured in the long-edge direction first, and then separation between face sheet and core happened. In the short-edge direction after core wrinkled, lower face sheet was torn, impact behavior by FE analysis were increased localized damage in high velocity because the faster velocity of the impact was, the smaller the stress of core was. Consequently, impactor weight had an effect on widely damaged area, while the impact velocity gave rise to localized damaged area.

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Vases, Caskets, and Decorative Lamps of the Leningrad Factory of Porcelain in 1956–1966: Context, Attribution, Interpretation

Izvestia of the Ural federal university Series 2 Humanities and Arts ◽

10.15826/izv2.2021.23.4.067 ◽

2021 ◽

Vol 23 (4) ◽

pp. 60-78

Author(s):

Olga S. Sapanzha ◽

Keyword(s):

Empty Space ◽

Living Environment ◽

Vast Number ◽

Second Stage ◽

Modern Style ◽

Post War ◽

The 1960S ◽

War Production ◽

The Many ◽

Two Stages

This paper focuses on two stages in the development of post-war production interior porcelain. The first stage is the completion of the development in the decorative and industrial arts of the grand style. The second stage is the development of modern style, which is reflected in the works of mass porcelain. The research refers to the Leningrad Factory of Porcelain and the production of the enterprise from 1956–1966. The products of the plant have not been studied sufficiently so far. However, the factory was one of the many Soviet porcelain enterprises that was involved in the creation of a new living environment. Two stages in the development of industrial art related to the organisation of the residential interior were reflected in the company’s products, i.e. works of small porcelain plastics, utilitarian porcelain, i.e. vases, boxes, bottles, night lamps, etc. The first stage is filled with works of small plastic arts (second half of the 1950s). The second stage is associated with the interior, in which porcelain goods played the role of accents in the interior, emphasising empty space (first half of the 1960s). The author of the article carries out analysis of caskets and vials of the enterprise (40 Years of October caskets, casket with a lion, Matryoshka casket, Summer Garden, a series of bottles and caskets), vases and pots (Lines planters, decorative vases, damask, and stacks), lamps (Chinese Pagoda night light, Golden Cockerel night light). Based on the interpretation of the value of the enterprise in the formation of the interior, the value of products in the processes of transition from the grand style to the modern style, a conclusion is drawn about the importance of the plant in the formation of the living environment. The massive nature of the works of the plant influenced the fact that the current stylistic trends were available to a vast number of Soviet citizens, who perceived new aesthetic norms.

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Boundaries in Spatial Cognition: Looking like a Boundary is More Important than Being a Boundary

10.1101/391037 ◽

2018 ◽

Author(s):

James Negen ◽

Angela Sandri ◽

Sang Ah Lee ◽

Marko Nardini

Keyword(s):

Empty Space ◽

Visual Features ◽

Spatial Coding ◽

Large Piece ◽

Two Factors ◽

Spatial Layouts ◽

Pass Through ◽

Visual Properties ◽

Target Locations ◽

3D Surfaces

ABSTRACTLarge walls and other typical boundaries strongly influence neural activity related to navigation and the representations of spatial layouts. They are also major aids to reliable navigation behavior in young children and non-human animals. Is this because they are physical boundaries (barriers to movement), or because they present certain visual features, such as visually extended 3D surfaces? Here, these two factors were dissociated by using immersive virtual reality and real boundaries. Eighty adults recalled target locations in one of four environments: plywood, where a virtual wall coincided with a large piece of real plywood; pass through, where the virtual wall coincided with empty space and participants could pass through it; pass over, where the virtual wall was projected downward to be visible underneath a transparent floor; and cones, where the walls were replaced with traffic cones. One condition had features that were boundaries and looked like boundaries (plywood); two had features that were not boundaries but looked like boundaries (pass over/through); and one had features that were not boundaries and did not look like boundaries (cones). The precision and bias of responses changed only as a function of looking like a boundary. This suggests that variations in spatial coding are more closely linked to the visual properties of environmental layouts than to whether they contain physical boundaries (barriers to movement).

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