scholarly journals Two explanations for the compliant running paradox: reduced work of bouncing viscera and increased stability in uneven terrain

2010 ◽  
Vol 6 (3) ◽  
pp. 418-421 ◽  
Author(s):  
Monica A. Daley ◽  
James R. Usherwood
Keyword(s):  
Fall Risk ◽  
Injury Risk ◽  
The Other ◽  
Apparent Paradox ◽  
Animal Locomotion ◽  
Trade Off ◽  
Uneven Terrain ◽  
Risk Optimization ◽  
Two Factors ◽  
Theoretical Predictions

Economy is a central principle for understanding animal locomotion. Yet, compared with theoretical predictions concerning economy, animals run with compliant legs that are energetically costly. Here, we address this apparent paradox, highlighting two factors that predict benefits for compliant gaits: (i) minimizing cost of work associated with bouncing viscera; and (ii) leg control for robust stability in uneven terrain. We show that consideration of the effects of bouncing viscera predicts an energetic optimum for relatively compliant legs. To compare stability in uneven terrain, we introduce the normalized maximum drop (NMD), a measure based on simple kinematics, which predicts that compliant legs allow negotiation of relatively larger terrain perturbations without failure. Our model also suggests an inherent trade-off in control of leg retraction velocity ( ω ) for stability: low ω allows higher NMD, reducing fall risk, whereas high ω minimizes peak forces with terrain drops, reducing injury risk. Optimization for one of these factors explicitly limits the other; however, compliant legs relax this trade-off, allowing greater stability by both measures. Our models suggest compromises in leg control for economy and stability that might explain why animals run with compliant legs.

scholarly journals Anthropomorphic Prosthetic Hand with Combination of Light Weight and Diversiform Motions

2019 ◽  
Vol 9 (20) ◽  
pp. 4203 ◽  
Author(s):  
Xiaobei Jing ◽  
Xu Yong ◽  
Yinlai Jiang ◽  
Guanglin Li ◽  
Hiroshi Yokoi
Keyword(s):  
Lightweight Design ◽  
The Other ◽  
Prosthetic Hand ◽  
Light Weight ◽  
Trade Off ◽  
Multiple Functions ◽  
Prosthetic Hands ◽  
Two Factors ◽  
Motion Performance ◽  
Limited Motion

Most prosthetic hands adopt an under-actuated mechanism to achieve dexterous motion performance with a lightweight and anthropomorphic design. Many have been verified in laboratories, and some have already been commercialized. However, a trade-off exists between the dexterity and the light weight of such prosthetic hands. In general, current commercially available prosthetic hands usually consider one aspect at the expense of the other, such as obtaining diversiform hand motions but an increased weight, or achieving lightweight design but with limited motion functions. This study attempts to attain a balance between the two factors, by realizing diversiform hand motions while reducing the weight as far as possible. An anthropomorphic prosthetic hand is proposed with only three servomotors embedded in a human-sized palm, with multiple functions, such as a stable/adaptive grasp and passive hyperextension. The proposed hand can achieve 13 grasp types with over 80% of the grasp motions under the Cutkosky taxonomy, while it weighs only 132.5 g, at less than 36% of the prosthesis weight limitation based on the study of Kay et al.

Factor Structure of the Hellenic WISC-III for Children with Learning Disabilities

2018 ◽  
Vol 9 (03) ◽  
pp. 20445-20451
Author(s):  
Adam A ◽  
Kiosseoglou G ◽  
Abatzoglou G ◽  
Papaligoura Z.
Keyword(s):  
Learning Disabilities ◽  
Factor Structure ◽  
Factor Model ◽  
The Other ◽  
Clinical Value ◽  
Reasoning Abilities ◽  
Picture Arrangement ◽  
Factorial Model ◽  
Verbal Subtest ◽  
Two Factors

The present research aims to examine the factor structure of the Hellenic WISC-III in a sample of 50 children with learning disabilities. The results show the existence of a factorial model with two factors, one aggregating the Comprehension verbal subtest with four performance subtests and the other the Picture Arrangement performance subtest with four verbal subtests. This two-factor model includes loadings in two factors that relate to the sequencing abilities and the verbal reasoning abilities of children. These findings assert the clinical value of the intelligence evaluation in these children.

scholarly journals Black Hole Algorithm for Sustainable Design of Counterfort Retaining Walls

2020 ◽  
Vol 12 (7) ◽  
pp. 2767 ◽  
Author(s):  
Víctor Yepes ◽  
José V. Martí ◽  
José García
Keyword(s):  
Black Hole ◽  
Sustainable Design ◽  
Retaining Walls ◽  
The Other ◽  
Trade Off ◽  
Construction Company ◽  
Geometric Variables ◽  
The Stability ◽  
The Cost ◽  
Black Hole Algorithm

The optimization of the cost and CO 2 emissions in earth-retaining walls is of relevance, since these structures are often used in civil engineering. The optimization of costs is essential for the competitiveness of the construction company, and the optimization of emissions is relevant in the environmental impact of construction. To address the optimization, black hole metaheuristics were used, along with a discretization mechanism based on min–max normalization. The stability of the algorithm was evaluated with respect to the solutions obtained; the steel and concrete values obtained in both optimizations were analyzed. Additionally, the geometric variables of the structure were compared. Finally, the results obtained were compared with another algorithm that solved the problem. The results show that there is a trade-off between the use of steel and concrete. The solutions that minimize CO 2 emissions prefer the use of concrete instead of those that optimize the cost. On the other hand, when comparing the geometric variables, it is seen that most remain similar in both optimizations except for the distance between buttresses. When comparing with another algorithm, the results show a good performance in optimization using the black hole algorithm.

scholarly journals Two Factors in Face Recognition: Whether You Know the Person’s Face and Whether You Share the Person’s Race

Perception ◽  
2021 ◽  
pp. 030100662110140
Author(s):  
Xingchen Zhou ◽  
A. M. Burton ◽  
Rob Jenkins
Keyword(s):  
Face Recognition ◽  
Factorial Design ◽  
Performance Measures ◽  
Recognition Accuracy ◽  
The Other ◽  
Familiarity Effect ◽  
Race Effect ◽  
Two Factors ◽  
Unfamiliar Face

One of the best-known phenomena in face recognition is the other-race effect, the observation that own-race faces are better remembered than other-race faces. However, previous studies have not put the magnitude of other-race effect in the context of other influences on face recognition. Here, we compared the effects of (a) a race manipulation (own-race/other-race face) and (b) a familiarity manipulation (familiar/unfamiliar face) in a 2 × 2 factorial design. We found that the familiarity effect was several times larger than the race effect in all performance measures. However, participants expected race to have a larger effect on others than it actually did. Face recognition accuracy depends much more on whether you know the person’s face than whether you share the same race.

scholarly journals Measuring the contribution of specialist vocabulary knowledge to academic achievement: disentangling effects of multiple types of word knowledge

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Ahmed Masrai ◽  
James Milton ◽  
Dina Abdel Salam El-Dakhs ◽  
Heba Elmenshawy
Keyword(s):  
Academic Achievement ◽  
Academic Success ◽  
Success Factors ◽  
Vocabulary Knowledge ◽  
The Other ◽  
Word Knowledge ◽  
Academic Vocabulary ◽  
Vocabulary Size ◽  
Two Factors ◽  
The Impact

AbstractThis study investigates the idea that knowledge of specialist subject vocabulary can make a significant and measurable impact on academic performance, separate from and additional to the impact of general and academic vocabulary knowledge. It tests the suggestion of Hyland and Tse (TESOL Quarterly, 41:235–253, 2007) that specialist vocabulary should be given more attention in teaching. Three types of vocabulary knowledge, general, academic and a specialist business vocabulary factors, are tested against GPA and a business module scores among students of business at a college in Egypt. The results show that while general vocabulary size has the greatest explanation of variance in the academic success factors, the other two factors - academic and a specialist business vocabulary - make separate and additional further contributions. The contribution to the explanation of variance made by specialist vocabulary knowledge is double that of academic vocabulary knowledge.

scholarly journals Determination of the Height of Hard X-Ray Sources in the Solar Atmosphere by Measurement of Photospheric Albedo Photons

1975 ◽  
Vol 68 ◽  
pp. 239-241
Author(s):  
John C. Brown ◽  
H. F. Van Beek
Keyword(s):  
Solar Atmosphere ◽  
The Other ◽  
X Ray ◽  
Theoretical Predictions ◽  
Source Models ◽  
The One

SummaryThe importance and difficulties of determining the height of hard X-ray sources in the solar atmosphere, in order to distinguish source models, have been discussed by Brown and McClymont (1974) and also in this Symposium (Brown, 1975; Datlowe, 1975). Theoretical predictions of this height, h, range between and 105 km above the photosphere for different models (Brown and McClymont, 1974; McClymont and Brown, 1974). Equally diverse values have been inferred from observations of synchronous chromospheric EUV bursts (Kane and Donnelly, 1971) on the one hand and from apparently behind-the-limb events (e.g. Datlowe, 1975) on the other.

Rolling and Recrystallization Textures in High Purity Al Cold Rolled to Very High Rolling Reductions

2005 ◽  
Vol 495-497 ◽  
pp. 603-608 ◽  
Author(s):  
Atsushi Todayama ◽  
Hirosuke Inagaki
Keyword(s):  
Cold Rolling ◽  
High Purity ◽  
Work Hardening ◽  
Dynamic Recovery ◽  
The Other ◽  
Rolling Reduction ◽  
Theoretical Investigations ◽  
Theoretical Predictions ◽  
Cold Rolled ◽  
Very High

On the basis of Taylor-Bishop-Hill’s theory, many previous theoretical investigations have predicted that, at high rolling reductions, most of orientations should rotate along theβfiber from {110}<112> to {123}<634> and finally into the {112}<111> stable end orientations. Although some exceptions exist, experimental observations have shown, on the other hand, that the maximum on the β fiber is located still at about {123}<634> even after 97 % cold rolling. In the present paper, high purity Al containing 50 ppm Cu was cold rolled up to 99.4 % reduction in thickness and examined whether {112}<111> stable end orientation could be achieved experimentally. It was found that, with increasing rolling reduction above 98 %, {110}<112> decreased, while orientations in the range between {123}<634> and {112}<111> increased, suggesting that crystal rotation along the βfiber from {110}<112> toward {123}<634> and {112}<111> in fact took place. At higher rolling reductions, however, further rotation of this peak toward {112}<111> was extremely sluggish, and even at the highest rolling reduction, it could not arrive at {112}<111>. Such discrepancies between theoretical predictions and experimental observations should be ascribed to the development of dislocation substructures, which were formed by concurrent work hardening and dynamic recovery. Since such development of dislocation substructures are not taken into account in Taylor-Bishop-Hill’s theory, it seems that they can not correctly predict the development of rolling textures at very high rolling reductions, i. e. stable end orientations. On annealing specimens rolled above 98 % reduction in thickness, cube textures were very weak, suggesting that cube bands were almost completely rotated into other orientations during cold rolling. {325}<496>, which lay at an intermediate position between {123}<634> and {112}<111> along theβfiber, developed strongly in the recrystallization textures.

Hypertriglyceridemia: Apheretic Treatment

2005 ◽  
Vol 28 (10) ◽  
pp. 1018-1024 ◽  
Author(s):  
G. Giannini ◽  
M. Valbonesi ◽  
F. Morelli ◽  
P. Carlier ◽  
M.C. De Luigi ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Acute Pancreatitis ◽  
Bone Marrow Transplantation ◽  
High Risk ◽  
Cyclosporin A ◽  
Marrow Transplantation ◽  
Removal Rate ◽  
The Other ◽  
Two Factors ◽  
High Triglyceride

Patients with extremely high triglyceride levels and associated lipemia are at high risk for acute pancreatitis. Two factors can increase triglyceride-rich lipoproteins; one is overproduction and other is a defect in clearance. Either mechanism can cause hypertriglyceridemia and both may exist simultaneously. Causes can be either primary or secondary. Plasmapheresis is efficacious for severe hypertryceridemia in patients who have not responded to previous therapies. We have treated 15 cases of hypertrygliceridemia complicating the course of patients receiving Cyclosporin A after bone marrow transplantation. Five patients were treated with plasmapheresis, the other ten with cascade filtration. The removal rate for triglycerides was 58.0% for patients treated by cascade filtration and 63.5% for patients treated by plasmapheresis. The removal rates for triglycerides were low possibly as a consequence of early saturation of the filter.

The Semantic Differential as an Index of Traffic Sign Perception and Comprehension

1977 ◽  
Vol 19 (2) ◽  
pp. 183-189 ◽  
Author(s):  
Robert E. Dewar ◽  
Jerry G. Ells
Keyword(s):  
Semantic Differential ◽  
The Other ◽  
Traffic Sign ◽  
Two Factors ◽  
Valid Instrument ◽  
Paper And Pencil ◽  
Verbal Messages ◽  
Highly Correlated

There is a need to develop and validate simple, inexpensive techniques for the evaluation of traffic sign messages. This paper examines the semantic differential (a paper-and-pencil test which measures psychological meaning) as a potential instrument for such evaluation. Two experiments are described, one relating semantic differential scores to comprehension and the other relating this index to glance legibility. The data indicate that semantic differential scores on all four factors (evaluative, activity, potency, and understandability) were highly correlated with comprehension of symbolic messages. These scores were unrelated to glance legibility of verbal messages, but two factors (evaluative and understandability) did correlate with glance legibility of symbolic messages. It was concluded that the semantic differential is a valid instrument for evaluating comprehension of symbolic sign messages and that it has advantages over other techniques.

Identifying opportunities for value chain development in the Kenyan coffee sector

2018 ◽  
Vol 47 (2) ◽  
pp. 150-159 ◽  
Author(s):  
Emerta Aragie
Keyword(s):  
Value Chain ◽  
Export Performance ◽  
Export Subsidy ◽  
The Other ◽  
Cash Crop ◽  
Trade Off ◽  
Cash Crops ◽  
Standard Value ◽  
Coffee Sector ◽  
Productivity Gains

By developing a model that describes the Kenyan coffee value chain, this study evaluates opportunities emanating from four scenarios representing productivity gains in the various value chain stages of the coffee sector and additional three scenarios reflecting shifts in market situations. Results show that productivity-enhancing policies have stronger effects on coffee output and export performance if they target the milling stage of the value chain. Export subsidy and favourable external marketing conditions also have stronger effects, distributed comparably across the various value chain stages. We, however, found that these gains in the coffee sector come at the expense of other cash crops such as cotton, tea, sugar and tobacco. The approach followed in this study is relevant as this trade-off between coffee and the other cash crop sectors may not be visibly shown using standard value chain approaches.

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