Visual enhancements in pick-and-place tasks: Human operators controlling a simulated cylindrical manipulator

A teleoperation simulator was constructed with vector display system, joysticks, and a simulated cylindrical manipulator, in order to quantitatively evaluate various display conditions. The first of two experiments conducted investigated the effects of perspective parameter variations on human operators' pick-and-place performance, using a monoscopic perspective display. The second experiment involved visual enhancements of the monoscopic perspective display, by adding a grid and reference lines, by comparison with visual enhancements of a stereoscopic display; results indicate that stereoscopy generally permits superior pick-and-place performance, but that monoscopy nevertheless allows equivalent performance when defined with appropriate perspective parameter values and adequate visual enhancements

Telerobotics: A simulation facility for university research

An experimental telerobotics (TR) simulation suitable for studying human operator (H.O.) performance is described. Simple manipulator pick-and-place and tracking tasks allowed quantitative comparison of a number of calligraphic display viewing conditions. A number of control modes could be compared in this TR simulation, including displacement, rate and acceleratory control using position and force joysticks. A homeomorphic controller turned out to be no better than joysticks; the adaptive properties of the H.O. can apparently permit quite good control over a variety of controller configurations and control modes. Training by optimal control example seemed helpful in preliminary experiments. An introduced communication delay was found to produce decrease in performance. In considerable part, this difficulty could be compensated for by preview control information. That neurological control of normal human movement contains a data period of 0.2 second may relate to this robustness of H.O. control to delay. The Ames-Berkeley enhanced perspective display was utilized in conjunction with an experimental helmet mounted display system (HMD) that provided stereoscopic enhanced views

The effect of breed on muscle fiber diameter and its relationship to palatability

The various groups that comprise the beef cattle industry have become quite cognizant of the fact that they are producing beef for the consumer and not just selling live animals. Until recent years, more interest was placed on production performance and quality than on carcass quality and cutability. The producer was interested primarily in getting his product to market, and was less concerned with the quality of the end product. Many producers did not know and others were confused as to the characteristics in the live animal that produced the most desirable carcass when hung on the rail. This left the production of highly desirable carcasses as a hit or miss proposition. Many things go into making up the quality factors in beef and present knowledge is lacking in many of these areas. Meat tenderness is one of the quality factors that is of prime concern to the consumer. Regardless of the flavor and Juiciness in a cut of meat, if the meat is not tender, the consumer will remember it as a poor cut. At the present time there is little basis for the con- sumer to use in selecting a tender cut of meat. This is one of the biggest problems facing the meat industry and researchers today. There are many factors that contribute to meat tenderness. Present knowledge of meat tenderness is confusing and in some cases contradictory. It was felt that a study of muscle fiber diameter would be timely in clearing up some of this confusion. With this purpose in mind, a study was undertaken to investigate differences in muscle fiber diameter and their relationship to tenderness, juiciness, flavor. shearing strength, panel evaluations, and other palatability and carcass characteristics

Petroleum ether extraction of tars

Thesis (B.S.)--University of Illinois, 1917.Typescript.Includes bibliographical references

Distribution of quantum incompatibility across subsets of measurements

Incompatible, i.e. non-jointly measurable quantum measurements are a necessary resource for many information processing tasks. It is known that increasing the number of distinct measurements usually enhances the incompatibility of a measurement scheme. However, it is generally unclear how large this enhancement is and on what it depends. Here, we show that the incompatibility which is gained via additional measurements is upper and lower bounded by certain functions of the incompatibility of subsets of the available measurements. We prove the tightness of some of our bounds by providing explicit examples based on mutually unbiased bases. Finally, we discuss the consequences of our results for the nonlocality that can be gained by enlarging the number of measurements in a Bell experiment.Comment: 6+13 pages, 2+1 figure

Quantifying Privacy: A Novel Entropy-Based Measure of Disclosure Risk

It is well recognised that data mining and statistical analysis pose a serious treat to privacy. This is true for financial, medical, criminal and marketing research. Numerous techniques have been proposed to protect privacy, including restriction and data modification. Recently proposed privacy models such as differential privacy and k-anonymity received a lot of attention and for the latter there are now several improvements of the original scheme, each removing some security shortcomings of the previous one. However, the challenge lies in evaluating and comparing privacy provided by various techniques. In this paper we propose a novel entropy based security measure that can be applied to any generalisation, restriction or data modification technique. We use our measure to empirically evaluate and compare a few popular methods, namely query restriction, sampling and noise addition.Comment: 20 pages, 4 figure

Addressing gaps in surgical skills training by means of low-cost simulation at Muhimbili University in Tanzania

<p>Abstract</p> <p>Background</p> <p>Providing basic surgical and emergency care in rural settings is essential, particularly in Tanzania, where the mortality burden addressable by emergency and surgical interventions has been estimated at 40%. However, the shortages of teaching faculty and insufficient learning resources have hampered the traditionally intensive surgical training apprenticeships. The Muhimbili University of Health and Allied Sciences consequently has experienced suboptimal preparation for graduates practising surgery in the field and a drop in medical graduates willing to become surgeons. To address the decline in circumstances, the first step was to enhance technical skills in general surgery and emergency procedures for senior medical students by designing and implementing a surgical skills practicum using locally developed simulation models.</p> <p>Methods</p> <p>A two-day training course in nine different emergency procedures and surgical skills based on the Canadian Network for International Surgery curriculum was developed. Simulation models for the surgical skills were created with locally available materials. The curriculum was pilot-tested with a cohort of 60 senior medical students who had completed their surgery rotation at Muhimbili University. Two measures were used to evaluate surgical skill performance: Objective Structured Clinical Examinations and surveys of self-perceived performance administered pre- and post-training.</p> <p>Results</p> <p>Thirty-six students participated in the study. Prior to the training, no student was able to correctly perform a surgical hand tie, only one student was able to correctly perform adult intubation and three students were able to correctly scrub, gown and glove. Performance improved after training, demonstrated by Objective Structured Clinical Examination scores that rose from 6/30 to 15/30. Students perceived great benefit from practical skills training. The cost of the training using low-tech simulation was four United States dollars per student.</p> <p>Conclusion</p> <p>Simulation is valued to gain experience in practising surgical skills prior to working with patients. In the context of resource-limited settings, an additional benefit is that of learning skills not otherwise obtainable. Further testing of this approach will determine its applicability to other resource-limited settings seeking to develop skill-based surgical and emergency procedure apprenticeships. Additionally, skill sustainability and readiness for actual surgical and emergency experiences need to be assessed.</p

Comparing Visitor Perceptions, Characteristics, and Support for Management Actions Before and During a Pilot Timed Entry System at Arches National Park

Over the past decade, many national park units in the United States broke visitation records. Arches National Park (UT, USA) is no exception. Between 2011 and 2021, visitation increased 74%. As part of considering management options to address the issues from sustained and concentrated visitation, Arches implemented a pilot timed entry system from 3 April to 3 October 2022. This article compares visitor perceptions, characteristics, and support for management actions before and during the pilot timed entry system using data from visitor intercept surveys. Findings suggest visitors experience quality improved across the park and on hiking trails during the pilot timed entry system. Visitor characteristics were extremely similar, and there were no differences in local residency, group size, vehicle occupancy, race, ethnicity, first time visitation, education level, or household income. Visitors were more likely to plan for the trip further in advance and were less likely to re-enter the park during the pilot timed entry system. Lastly, visitors demonstrated more support for timed entry and lower levels of support for expanding parking, site specific reservations, and temporary closures during the pilot timed entry system. These results reflect unique insights for managers considering managed access systems like timed entry to sustainably manage visitor use in parks and protected areas