Task parameters affecting human physical ability and willingness to lift: An ecological approach

2003 ◽  
Vol 3 (2) ◽  
pp. 109-119
Author(s):  
Waldemar Karwowski ◽  
Krystyna Gielo-Perczak ◽  
David Moxley ◽  
David Rodrick
Keyword(s):  
Material Handling ◽  
Open Space ◽  
Human Perception ◽  
Ecological Approach ◽  
Confined Space ◽  
Physical Ability ◽  
Black Boxes ◽  
Average Maximum ◽  
Task Parameters ◽  
Ability And Willingness

The objective of this study was to analyze human perception of load heaviness in manual material handling tasks under varying task parameters taking into consideration participants' physical ability and willingness to lift loads. These conditions were: 1) box color, 2) instruction set, and 3) space confinement. The effect of each parameter on the maximum acceptable weight that people are willing to lift was investigated. This study showed that the box color significantly affects a participant's perception of weight. The average maximum acceptable weight participants were willing to lift was higher for the black boxes than for the white boxes in both open and constrained spaces. When using the white boxes, the maximum acceptable weight participants were willing to lift was smaller in the confined space than in the open space. This study introduces an ecological approach to manual handling tasks and proposes the paradigm of maximum acceptable weight of load (MAWL) to the maximum loads that people perceive they are able and willing to lift (MLWL).

Examining human perception of weight during loaded standing and walking

2021 ◽  
Vol 65 (1) ◽  
pp. 101-105
Author(s):  
Ken Chen ◽  
Karen B. Chen ◽  
Edward P. Fitts
Keyword(s):  
Material Handling ◽  
Subjective Evaluation ◽  
Weight Perception ◽  
Weight Ratio ◽  
Human Perception ◽  
Logistic Regression Models ◽  
Manual Material Handling ◽  
Weight Level ◽  
Therapeutic Exercises ◽  
Reference Weight

While the psychophysics of weight perception may help assess the effort needed in manual material handling tasks, the perception of weight is subjective and not necessarily accurate. The purpose of this study was to examine weight perception during standing and walking. Participants (n=10) performed a series of weight comparison trials against a reference load while holding loads (standing) or carrying loads (walking). Polynomial logistic regression models were built to examine the effects of walking, box weight ratio, and reference weight level on the probability of detecting a weight difference. The results showed that weight ratio and reference weight level had statistically significant effects on the detection probability while walking did not have a significant effect. Findings from this study can help inform the design of subjective evaluation of job demands involving motion, and it can be further extended to the gradual increase in load of strengthening tasks in therapeutic exercises.

scholarly journals Building Configuration of Low-Cost Apartments in Bandung—Its Contribution to the Microclimate and Outdoor Thermal Comfort

Buildings ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 123 ◽  
Author(s):  
Beta Paramita ◽  
Hiroatsu Fukuda ◽  
Rendy Perdana Khidmat ◽  
Andreas Matzarakis
Keyword(s):  
Thermal Comfort ◽  
Open Space ◽  
Low Cost ◽  
Human Perception ◽  
Ground Cover ◽  
Outdoor Thermal Comfort ◽  
Humid Climate ◽  
Hot Humid Climate ◽  
Radiant Temperature ◽  
Building Form

This paper aims to find the microclimate aspect within the building form and configuration of five low-cost apartments (henceforth rusun) in Bandung, Indonesia. There are parallel, square, and interspersed plots investigated with specific discussion on the microclimate aspects that gain human perception of outdoor thermal comfort. The microclimate prognostic model, i.e., ENVI-met, was used to determine the mean radiant temperature (Tmrt), which was then used to describe the living quality of outdoor thermal comfort, i.e., PET (physiologically equivalent temperature) in a hot-humid climate context. A parallel plot with building orientation toward north-south was found as the most beneficial building form and configuration. Somehow, the parallel plot toward the west-east orientation did not provide similar performance. Nevertheless, the square plot provided uncomfortable perception as there was an absence of building shade within the wide open space and ground cover to absorb the insolation. The interspersed plot can be considered for the building configuration because it generates more wind among other plots. The building form and configuration of rusun with passive design seems to not be able to achieve outdoor thermal comfort. The highest PET value of Model D with the square plot had PET = 41 °C (hot) while the lowest PET in Model A with the parallel plot (N-S) had PET = 34.2 °C (slightly warm).

Sensing urban poverty: From the perspective of human perception-based greenery and open-space landscapes

2020 ◽  
Vol 84 ◽  
pp. 101544
Author(s):  
Yuan Meng ◽  
Hanfa Xing ◽  
Yuan Yuan ◽  
Man Sing Wong ◽  
Kaixuan Fan
Keyword(s):  
Open Space ◽  
Urban Poverty ◽  
Human Perception

scholarly journals Assessment of medium parameters in a closed space for a Hyperloop transport capsule with reference to reducing the energy demand of a transport system

2019 ◽  
Vol 108 ◽  
pp. 01032 ◽  
Author(s):  
Marcin Nowacki ◽  
Damian Olejniczak ◽  
Jarosław Markowski
Keyword(s):  
Transport System ◽  
Energy Demand ◽  
Open Space ◽  
Social Systems ◽  
Rail Transport ◽  
Transport Systems ◽  
Confined Space ◽  
New Concepts ◽  
Specific Analysis ◽  
Numerical Tools

The increasing transport needs of societies are prompting manufacturers and inventors to seek new ways to satisfy them which are closely related to the development of new transport systems and means of transport. The current level of technological and social systems imposes limits on the implementation of new concepts which combine the advantages of existing systems currently functioning as separate entities. Combining the advantages of rail transport with the characteristics of air transport gave rise to the concept of a new transport system called Hyperloop, whose main purpose is to create a transport network combining the advantages of air and rail transport with low operating costs. The project assumes a pipeline structure and a transport capsule that moves inside its channels. To obtain high-velocity capsules, it is assumed that the pressure in the pipeline will be reduced, which will reduce in turn the losses resulting from the resistance of the moving capsule. Most means of transport in current use involve motion in open space. The proposed Hyperloop system involves different problems concerning the movement of the capsule as a means of transport within the confined space of the pipeline. These problems require specific analysis of conditions inside the system which depend on the velocity and shape of the capsule. These issues can be addressed using currently available numerical tools. An attempt to assess the phenomena associated with the flow of the capsule, using an important factor found in the pipeline space, was undertaken in the analyses conducted here. The study involved determination of the force acting on the nose of the capsule, an important component of its resistance to movement. The results and analyses were used to evaluate the differences in energy demand between two compared structures. On the basis of these results, conclusions were drawn regarding the directions for further modifications of the shape of the capsule aimed at reducing the energy demand necessary for its propulsion.

scholarly journals Do urban open spaces provide refugia for frogs in urban environments?

PLoS ONE ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. e0244932
Author(s):  
David Hutto ◽  
Kyle Barrett
Keyword(s):  
South Carolina ◽  
Species Richness ◽  
Open Space ◽  
Buffer Zone ◽  
Impervious Surface ◽  
Habitat Destruction ◽  
Suitable Habitat ◽  
Open Spaces ◽  
Urban Open Space ◽  
Average Maximum

Urbanization is among the largest threats to wildlife populations through factors such as fragmentation, isolation, and habitat destruction. Urban open spaces, such as parks and golf courses, have the potential to provide wildlife with suitable habitat within an urbanized matrix. These refugia may be particularly important for amphibians, which represent one of the most endangered and least vagile vertebrate groups on earth. During the spring and summer of 2018, we conducted surveys to determine the presence of anurans at 51 wetland sites within the Piedmont ecoregion of South Carolina. Nearly one-third of these wetlands were located within urban open spaces, one-third in low development areas, and one-third in highly developed areas. Impervious surface and total road length surrounding the wetlands were measured at two scales, a core habitat scale (300 m) and average maximum migration scale (750 m), and we measured several within-wetland habitat variables. Urban Open Space wetlands had levels of surrounding impervious surface similar to High Urbanization wetlands at the larger scale and were intermediate between Low and High Urbanization wetlands at the smaller scale. The total length of road segments occurring within buffers (at both scales) surrounding our study wetlands was higher for Urban Open Space compared to Low and High Urbanization sites. Among the within-wetland variables measured, Low Urbanization sites had higher canopy cover and were more likely to have a terrestrial buffer zone relative to the other categories. Species richness decreased significantly as total road length increased among all wetlands. Wetland category was not a significant driver explaining species richness, but β-diversity was more variable among Urban Open Space wetlands than either Low or High Urbanization wetlands. Urban Open Space wetlands did not appear to increase suitability for anurans relative to High Urbanization wetlands. Urban Open Space wetlands had higher variability in species composition, which was perhaps attributable to the diversity among sites represented in the Urban Open Space category.

scholarly journals Bats adjust their mouth gape to zoom their biosonar field of view

2015 ◽  
Vol 112 (21) ◽  
pp. 6724-6729 ◽  
Author(s):  
Pavel Kounitsky ◽  
Jens Rydell ◽  
Eran Amichai ◽  
Arjan Boonman ◽  
Ofri Eitan ◽  
...  
Keyword(s):  
Open Space ◽  
Sensory Information ◽  
Field Of View ◽  
Active Sensing ◽  
Confined Space ◽  
Sound Beam ◽  
Freely Behaving ◽  
The One ◽  
Almost All ◽  
Inherent Component

Active sensing, where sensory acquisition is actively modulated, is an inherent component of almost all sensory systems. Echolocating bats are a prime example of active sensing. They can rapidly adjust many of their biosonar parameters to optimize sensory acquisition. They dynamically adjust pulse design, pulse duration, and pulse rate within dozens of milliseconds according to the sensory information that is required for the task that they are performing. The least studied and least understood degree of freedom in echolocation is emission beamforming—the ability to change the shape of the sonar sound beam in a functional way. Such an ability could have a great impact on the bat’s control over its sensory perception. On the one hand, the bat could direct more energy into a narrow sector to zoom its biosonar field of view, and on the other hand, it could widen the beam to increase the space that it senses. We show that freely behaving bats constantly control their biosonar field of view in natural situations by rapidly adjusting their emitter aperture—the mouth gape. The bats dramatically narrowed the beam when entering a confined space, and they dramatically widened it within dozens of milliseconds when flying toward open space. Hence, mouth-emitting bats dynamically adjust their mouth gape to optimize the area that they sense with their echolocation system.

scholarly journals Fiber Optic Projection-Imaging System for Shape Measurement in Confined Space

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Lujie Chen ◽  
Viswanath Bavigadda ◽  
Theodoros Kofidis ◽  
Robert D. Howe
Keyword(s):  
Open Space ◽  
Fiber Optic ◽  
Flat Surface ◽  
Imaging System ◽  
Phase Measurement ◽  
High Accuracy ◽  
Shape Measurement ◽  
Confined Space ◽  
Closed Space ◽  
Fringe Patterns

A fiber-based projection-imaging system is proposed for shape measurement in confined space. Owing to the flexibility of imaging fibers, the system can be used in special scenarios that are difficult for conventional experimental setups. Three experiments: open space, closed space, and underwater are designed to demonstrate the strength and weakness of the system. It is shown that when proper alignment is possible, relatively high accuracy can be achieved; the error is less than 2% of the overall height of a specimen. In situations where alignment is difficult, significantly increased error is observed. The error is in the form of gross-scale geometrical distortion; for example, flat surface is reconstructed with curvature. In addition, the imaging fibers may introduce fine-scale noise into phase measurement, which has to be suppressed by smoothing filters. Based on results and analysis, it is found that although a fiber-based system has its unique strength, existing calibration and processing methods for fringe patterns have to be modified to overcome its drawbacks so as to accommodate wider applications.

Microbulldozing and Microchiseling

1969 ◽  
Vol 27 ◽  
pp. 134-135
Author(s):  
J.N. Ramsey ◽  
D.P. Cameron ◽  
F.W. Schneider
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Material Handling ◽  
Microprobe Analysis ◽  
Foreign Matter ◽  
Specific Location ◽  
Potential Problems ◽  
Knoop Indenter ◽  
Scanning Electron ◽  
Microhardness Tester

As computer components become smaller the analytical methods used to examine them and the material handling techniques must become more sensitive, and more sophisticated. We have used microbulldozing and microchiseling in conjunction with scanning electron microscopy, replica electron microscopy, and microprobe analysis for studying actual and potential problems with developmental and pilot line devices. Foreign matter, corrosion, etc, in specific locations are mechanically loosened from their substrates and removed by “extraction replication,” and examined in the appropriate instrument. The mechanical loosening is done in a controlled manner by using a microhardness tester—we use the attachment designed for our Reichert metallograph. The working tool is a pyramid shaped diamond (a Knoop indenter) which can be pushed into the specimen with a controlled pressure and in a specific location.

Development of high-performance objective lens polepiece for ultrahigh resolution Analytical Electron Microscope

1993 ◽  
Vol 51 ◽  
pp. 254-255
Author(s):  
K. Fukushima ◽  
T. Kaneyama ◽  
F. Hosokawa ◽  
H. Tsuno ◽  
T. Honda ◽  
...  
Keyword(s):  
Electron Microscope ◽  
High Performance ◽  
Open Space ◽  
Materials Science ◽  
Objective Lens ◽  
Ultrahigh Resolution ◽  
Science Field ◽  
Specimen Holder ◽  
Analytical Electron ◽  
Analytical Electron Microscope

Recently, in the materials science field, the ultrahigh resolution analytical electron microscope (UHRAEM) has become a very important instrument to study extremely fine areas of the specimen. The requirements related to the performance of the UHRAEM are becoming gradually severer. Some basic characteristic features required of an objective lens are as follows, and the practical performance of the UHRAEM should be judged by totally evaluating them.1) Ultrahigh resolution to resolve ultrafine structure by atomic-level observation.2) Nanometer probe analysis to analyse the constituent elements in nm-areas of the specimen.3) Better performance of x-ray detection for EDS analysis, that is, higher take-off angle and larger detection solid angle.4) Higher specimen tilting angle to adjust the specimen orientation.To attain these requirements simultaneously, the objective lens polepiece must have smaller spherical and chromatic aberration coefficients and must keep enough open space around the specimen holder in it.

Black Boxes Added To Labels for Elidel And Protopic

2005 ◽  
Vol 39 (4) ◽  
pp. 1-3
Author(s):  
DEEANNA FRANKLIN
Keyword(s):  
Black Boxes
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