Development of Walking Pattern Evaluation System for Hypogravity Simulation

2008 ◽  
pp. 440-445
Author(s):  
R. Leães ◽  
R. Cambraia ◽  
F. Bacim ◽  
G. Dalmarco ◽  
A. Calder ◽  
...  
Keyword(s):  
Evaluation System ◽  
Water Immersion ◽  
Parabolic Flight ◽  
Time Constraints ◽  
Hydrodynamic Drag ◽  
Neutral Buoyancy ◽  
Freedom Of Movement ◽  
Partial Gravity ◽  
The Subject ◽  
Neutrally Buoyant

There are three primary techniques for simulating partial gravity: water immersion (neutral buoyancy), parabolic flight, and body suspension device (BSD) models. Underwater Immersion. During tests, a neutrally buoyant subject is ballasted to simulate the desired partial gravity loading. For example, one-sixth of the subject’s body mass is added in ballast if a lunar simulation is desired. Water immersion offers the subject freedom from time constraints and freedom of movement, but the hydrodynamic drag is disadvantageous for movement studies.

scholarly journals Stable hooks: biomechanics of heteromorph ammonoids with U-shaped body chambers

2020 ◽  
Vol 86 (4) ◽  
pp. 267-279
Author(s):  
David J Peterman ◽  
Ryan Shell ◽  
Charles N Ciampaglio ◽  
Margaret M Yacobucci
Keyword(s):  
Intermediate Stage ◽  
Physical Models ◽  
Mature Stage ◽  
Hydrodynamic Drag ◽  
Centre Of Mass ◽  
Neutral Buoyancy ◽  
Selective Pressures ◽  
Adult Model ◽  
3D Printed ◽  
Neutrally Buoyant

ABSTRACT The biomechanics of uncoiled heteromorph ammonoids with body chambers that terminate in U-shaped hooks (ancylocones) were investigated with virtual and physical models of Audouliceras renauxianum. Virtual models were used to compute the hydrostatic properties of this morphotype. Audouliceras has the capacity for neutral buoyancy and this suggests that other taxa with similar proportions had this ability as well. Hydrostatic stability gradually increases during ontogeny, coincident with the larger degree of uncoiling. The juvenile planispiral stage has a similar stability and apertural orientation to the extant Nautilus. The adult stage, however, undergoes an increase in stability by a factor of over 3, while assuming an upward-facing posture. Counterintuitively, the stage during the formation of the shaft (before the growth of the U-shaped hook) is oriented horizontally. This intermediate stage would have had poor horizontal mobility due to the positioning of the hyponome below the centre of mass. The juvenile planispiral stage and mature stage, however, would have been well suited to horizontal backward movement with minimal rocking. Ancylocones are generally thought of as quasiplanktic vertical migrants. Thus, their relative horizontal swimming ability has been largely disregarded. Experiments on 3D printed, neutrally buoyant physical models reveal that hydrodynamic drag is indeed larger compared to Nautilus. However, Audouliceras could reach similar maximum horizontal velocities depending on the available thrust. Sepia-like thrusts yield velocities similar to equivalently sized Nautilus (c. 15 cm/s), while Nautilus-like thrusts yield velocities not much lower (c. 11 cm/s). Due to the hydrostatic properties of the ancylocone, the adult model undergoes less rocking (±4.5°) during movement than Nautilus (±10°). The minimal hydrodynamic consequences for ancylocones suggest that stability, orientation and directional efficiency are key selective pressures for some heteromorph shells, which may have primarily served as hydrostatic devices.

Heart-Rate Response to Water-Immersion Isolation as a Function of Spatial Orientation

1988 ◽  
Vol 67 (1) ◽  
pp. 163-167
Author(s):  
Donald G. Forgays ◽  
Gary McClure
Keyword(s):  
Heart Rate ◽  
Spatial Orientation ◽  
Water Immersion ◽  
The Body ◽  
Neutral Buoyancy ◽  
Heart Rate Data ◽  
Body Attitude ◽  
Significant Difference ◽  
The Subject ◽  
Response To Water

The present study investigates the effect of spatial orientation of the body on heart rate during conditions of water-immersion sensory isolation. Two groups of three men and three women each were exposed to one of two isolation conditions. In one condition the subject was suspended in a buoyant but vertical attitude; in a second condition the subject was suspended in a buoyant but horizontal attitude. Heart-rate data were obtained continuously during each session. There was no significant difference in mean heart rate between the two conditions. The data were interpreted as providing support for the position that studies comparing recumbent subjects in air isolation with underwater subjects in a vertical suspension attitude are valid, at least for some measures, and are not an artifact of spatial bodily orientation. The possible importance of neutral buoyancy in accounting for the nonsignificant effect of body attitude on heart rate is discussed.

scholarly journals Strategi Evaluasi Program Praktikum Fisika Dasar

2018 ◽  
Vol 9 (1) ◽  
pp. 12
Author(s):  
Erwin Erwin ◽  
I Permana ◽  
Muhammad Syaipul Hayat
Keyword(s):  
Evaluation System ◽  
Information Support ◽  
Practical Implementation ◽  
Accurate Data ◽  
Input Process ◽  
Scientific Methods ◽  
Evaluation Approach ◽  
The Subject ◽  
The Right

Lab work is one of the ways taken not only to clarify the subject that have been taught but also to coached students to apply scientific methods in solving problems. In order to ensure the quality of practical implementation requires accurate data-based information support, a gradual evaluation system is needed to help make the right decisions in every action throughout the program. The evaluation approach used is the CIPP (context, input, process, and product). Data collection is through interviews, questionnaires and direct observation, The data collected at each stage of the evaluation were analyzed qualitatively with the descriptions

On the use of ammonium for buoyancy in squids

1979 ◽  
Vol 59 (2) ◽  
pp. 259-276 ◽  
Author(s):  
M. R. Clarke ◽  
E. J. Denton ◽  
J. B. Gilpin-Brown
Keyword(s):  
Developmental Stage ◽  
Sea Water ◽  
The Body ◽  
The Other ◽  
Neutral Buoyancy ◽  
Rich Solution ◽  
Almost All ◽  
Neutrally Buoyant

Squids (teuthoids) fall into two distinct groups according to their density in sea water. Squids of one group are considerably denser than sea water and must swim to stop sinking; squids in the other group are nearly neutrally buoyant. Analyses show that in almost all the neutrally buoyant squids large amounts of ammonium are present. This ammonium is not uniformly distributed throughout the body but is mostly confined to special tissues where its concentration can approach half molar. The locations of such tissues differ according to the species and developmental stage of the squid. It is clear that the ammonium-rich solution are almost isosmotic with sea water but of lower density and they are present in sufficient volume to provide the main buoyancy mechanism of these squids. A variety of evidence is given which suggests that squids in no less than 12 of the 26 families achieve near-neutral buoyancy in this way and that 14 families contain squids appreciably denser than sea water [at least one family contains both types of squid]. Some of the ammonium-rich squids are extremely abundant in the oceans.

Human Factors Review of Space Habitat Feature Requirements

2017 ◽  
Vol 61 (1) ◽  
pp. 62-62
Author(s):  
James Flores ◽  
Farzan Sasangohar
Keyword(s):  
Parabolic Flight ◽  
Vertical Displacement ◽  
Human Motion ◽  
The Moon ◽  
Friction Forces ◽  
Transition Speed ◽  
Human Scale ◽  
Partial Gravity ◽  
Ceiling Height ◽  
Reaction Forces

Sending humans to other planets requires an understanding of the effects of the partial gravity on human motion before attempting to design or build buildings or plan mission tasks. Architecture is the most basic example of human-centered design as everything in a building is to “human” scale. While some modern studies (e.g., Capps, et. al, 1989) reference a study which looked at the humans and forces for the Moon landing (Hewes et. al, 1966), this study was never correlated with the actual lunar data and has many erroneous assumptions. Previous work in Biomechanics was reviewed and the elements of physics required to analyze human motion in partial gravity was analyzed and several basic questions were generated. Included in these studies are NASA studies which look at parabolic flight and apparatus to simulate the effects of partial gravity (NASA/TM-2010-216139, 2010). The key part of physics that drives the changes in human motion is the fact that the momentum of a human or object in motion remains the same while gravity reduces the normal forces on the feet which in turn cause a reduction in the friction reaction forces available for maneuvering or stopping. The study investigates design of several building features for space architecture. These include: Ceiling Height, Door Size, Railing Height, Stairs, Ladders, and Ramps. The first of these the ceiling height relates to the question of does a person “bounce” when they walk in partial gravity. Typical ceilings on Earth range from 2.44 m (8 feet) to 3.05 m (10 feet) Studies of walk to run transition speed for partial gravity were reviewed and they measured the vertical displacement of the hip. This measurement varied by less than 1 cm and correlated to a minimal head height change. Door sizes and railing heights related to the height of 99th percentile humans projected to the year of launch to Mars or the Moon and also included spinal growth caused by 0 g transit. These projections do lead to a taller door opening (25 cm) and raised railing (14.3 cm) as compared to earth. Stairs and ladders both ended up being related to joint angles and human preferences such that they remain the same as on Earth. Chair heights which also relate to counter heights were looked at by reviewing studies of the sit-to-stand motion and comparing the foot and buttocks reaction forces to the friction forces available on Mars and the Moon verses Earth standard. This leads to a recommendation to use Pub height chairs and counters. Flooring and ramps required scaling and also calculating equivalency values to make comparisons. It was determined that the required friction when scaled to Mars would be possible with fairly standard flooring materials. The Lunar case however, would require a combination of high friction flooring and training for nominal movement. To analyze ramps independent calculations were used for friction requirements and then correlated to a study of emergency personnel pushing a trolley with a patient up or down a ramp. Both these methods correlated to an extremely shallow 2.86 degrees (slope 1 in 20) ramp being possible on Mars and ramps not being usable on the Moon. Based on these factors it is recommended that many of features follow standards used on earth and that only the required changes be made such that the habitation resemble Earth structures as much as possible. In addition, Astronaut training should incorporate these factors into their procedures.

In situ acoustic estimates of the swimbladder volume of Atlantic herring (Clupea harengus)

2004 ◽  
Vol 61 (3) ◽  
pp. 323-337 ◽  
Author(s):  
Redwood W. Nero ◽  
Charles H. Thompson ◽  
J. Michael Jech
Keyword(s):  
Gulf Of Maine ◽  
Clupea Harengus ◽  
Sea Surface ◽  
Atlantic Herring ◽  
Acoustic Measurements ◽  
Neutral Buoyancy ◽  
Fish Weight ◽  
Neutrally Buoyant ◽  
Boyle’S Law

Abstract Acoustic measurements at 1.5–5 kHz on fish in the Gulf of Maine showed a swimbladder-resonance peak near 2.5 kHz at 160–190-m depth. Midwater trawls confirmed that the fish were likely to be Atlantic herring (Clupea harengus) of 19–29 cm length. Calculation using a model of swimbladder resonance gives swimbladder volumes of 1.2% of fish weight at 160–190 m. Extrapolation of this volume of gas using Boyle's Law suggests that at the sea surface, these herring would need to inflate their swimbladders by up to five to six times the volume required for neutral buoyancy. If these fish were to maintain this volume of gas with surface “gulping”, they would need to submerge from the sea surface with a 30% excess buoyancy. In general, swimbladders of the Clupeidae may have greater volumes of gas than if the fish were neutrally buoyant at the sea surface and the interpretation of HF-echosounder surveys may be additionally complex when the volume of gas and swimbladder volume are difficult to predict. Mechanisms of how herring obtain additional swimbladder gas are discussed.

scholarly journals Clinical Usefulness of Self-Rated Olfactory Performance—A Data Science-Based Assessment of 6000 Patients

2019 ◽  
Vol 44 (6) ◽  
pp. 357-364 ◽  
Author(s):  
Jörn Lötsch ◽  
Thomas Hummel
Keyword(s):  
Clinical Practice ◽  
Test Performance ◽  
Data Science ◽  
False Negative ◽  
Time Constraints ◽  
Accurate Information ◽  
Olfactory Testing ◽  
Identification Test ◽  
The Subject ◽  
University Department

Abstract In clinical practice, with its time constraints, a frequent conclusion is that asking about the ability to smell may suffice to detect olfactory problems. To address this question systematically, 6049 subjects were asked about how well they can perceive odors, with 5 possible responses. Participants presented at a University Department of Otorhinolaryngology, where olfactory testing was part of the routine investigation performed in patients receiving surgery at the clinic (for various reasons). According to an odor identification test, 1227 subjects had functional anosmia and 3113 were labeled with normosmia. Measures of laboratory test performance were used to assess the success of self-estimates to capture the olfactory diagnosis. Ratings of the olfactory function as absent or impaired provided the diagnosis of anosmia at a balanced accuracy of 79%, whereas ratings of good or excellent indicated normosmia at a balanced accuracy of 64.6%. The number of incorrect judgments of anosmia increased with age, whereas false negative self-estimates of normosmia became rarer with increasing age. The subject’s sex was irrelevant in this context. Thus, when asking the question “How well can you smell odors?” and querying standardized responses, fairly accurate information can be obtained about whether or not the subject can smell. However, this has to be completed with the almost 30% (355 subjects) of anosmic patients who judged their ability to smell as at least “average.” Thus, olfactory testing using reliable and validated tests appears indispensable.

scholarly journals Possible consequences of the COVID-19 pandemic on the mental health of employees in travel agencies in Serbia

2020 ◽  
pp. 63-74
Author(s):  
Jelisaveta Vučković ◽  
Vesna Tsitsivas
Keyword(s):  
Mental Health ◽  
Prospective Studies ◽  
Tourism Industry ◽  
World Health ◽  
Freedom Of Movement ◽  
Business Operations ◽  
Travel Agencies ◽  
The World ◽  
The Subject ◽  
Health Organization

On March 11, 2020, the World Health Organization declared COVID-19 virus pandemic, which is still ongoing, and it is uncertain when it will end. Essentially, it is an epidemiological problem which has turned into economic, sociological, socio-political and psychological one. Based on the information available so far, it can be concluded that the tourism industry (and within it, especially the business operations of travel agencies and tour operators), both in the world and in Serbia, is one of the most affected, due to the pandemic. Freedom of movement is restricted and people's safety is endangered, which are the key preconditions for tourism mobility. The subject of analysis in this paper is an attempt to look at the psychological aspect of the COVID-19 virus pandemic, with special emphasis on its possible consequences on the mental health of the employees in travel agencies in Serbia. Meny experts think that it will undoubtedly adversely affect people's mental health, and prospective studies on this topic will follow in the future.

scholarly journals Akurasi dan Akuntabilitas Penilaian Kinerja Guru Pendidikan Agama Islam

ULUMUNA ◽  
2017 ◽  
Vol 18 (1) ◽  
pp. 221-242
Author(s):  
Lubna Lubna
Keyword(s):  
Religious Education ◽  
Evaluation System ◽  
Teacher Performance ◽  
Professional Skills ◽  
Assessment And Evaluation ◽  
Regular Control ◽  
Professional Teacher ◽  
The Subject ◽  
Evaluation And Assessment

There are a great number of teachers of Islamic religious education who hold a professional diploma and yet have not realized the tasks of competent professional teacher. The four indicators of competent and professional teacher, as these are elaborated in Statutes and Regulations, have not been integrated in teacher performance. This problem must be resolved. It requires a system that can control the implementation of the principles of professional teacher while at the same time does not ruin teacher’s profession and capability. This article offers professional-based assessment and evaluation of teacher performance as a medium for a regular control. This system will be able to measure teacher performance referring to their skills and to avoid deviation in the evaluation between what is taught and the subject being taught concerning teachers’ professional skills. With this professional-based evaluation system, the processes of evaluation and assessment become objective, accurate and accountable.

scholarly journals Students' Beliefs on Portfolio Assessment

2013 ◽  
pp. 225
Author(s):  
Andrés Canga Alonso
Keyword(s):  
Higher Education ◽  
Evaluation System ◽  
Portfolio Assessment ◽  
Assessment Tools ◽  
Learning Tools ◽  
English Studies ◽  
Spanish Translation ◽  
Final Exam ◽  
Active Involvement ◽  
The Subject

The development of the European Space for Higher Education (ESHE) not only encourages students’ active involvement in their learning process, but also promotes formative assessment. Therefore, the aim of this research is to analyse students´ beliefs on portfolio assessment in the subject Spanish-English/English-Spanish Translation of the degree in English Studies at a university in Spain. A questionnaire was administered at the end of the semester to check learners’ views on the implementation of an evaluation system based on portfolios. The results indicate that most of the students involved in the study recognise that using portfolios as assessment tools foster their learning since these learning tools favour reflection on one’s own learning as well as revision for the final exam. Contrariwise, learners think that portfolio assembling is time consuming and implies hard work. However, they also feel it is rewarding since they get a better grade at the end of the semester.

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