Configuration control of seven-degree-of-freedom arms

A seven degree of freedom robot arm with a six degree of freedom end effector is controlled by a processor employing a 6 by 7 Jacobian matrix for defining location and orientation of the end effector in terms of the rotation angles of the joints, a 1 (or more) by 7 Jacobian matrix for defining 1 (or more) user specified kinematic functions constraining location or movement of selected portions of the arm in terms of the joint angles, the processor combining the two Jacobian matrices to produce an augmented 7 (or more) by 7 Jacobian matrix, the processor effecting control by computing in accordance with forward kinematics from the augmented 7 by 7 Jacobian matrix and from the seven joint angles of the arm a set of seven desired joint angles for transmittal to the joint servo loops of the arm. One of the kinematic functions constraints the orientation of the elbow plane of the arm. Another one of the kinematic functions minimizes a sum of gravitational torques on the joints. Still another kinematic function constrains the location of the arm to perform collision avoidance. Generically, one kinematic function minimizes a sum of selected mechanical parameters of at least some of the joints associated with weighting coefficients which may be changed during arm movement. The mechanical parameters may be velocity errors or gravity torques associated with individual joints

Remote surface inspection system

This paper reports on an on-going research and development effort in remote surface inspection of space platforms such as the Space Station Freedom (SSF). It describes the space environment and identifies the types of damage for which to search. This paper provides an overview of the Remote Surface Inspection System that was developed to conduct proof-of-concept demonstrations and to perform experiments in a laboratory environment. Specifically, the paper describes three technology areas: (1) manipulator control for sensor placement; (2) automated non-contact inspection to detect and classify flaws; and (3) an operator interface to command the system interactively and receive raw or processed sensor data. Initial findings for the automated and human visual inspection tests are reported

MEMBRANE ACTION IN PROFILED STEEL SHEETING DRY BOARD (PSSDB) FLOOR SLAB SYSTEM

Profiled steel sheeting dry board (PSSDB) system is a lightweight composite structural system that made of the profiled steel sheeting (PSS) connected to the dry board (DB) by self-drilling and self-tapping screws. The objective of this paper is to study the effect of membrane action in improving the flexural capacities of the PSSDB system. According to the literatures, common failure of the PSSDB floor is due to local buckling in the top flanges of steel sheeting at the centre of a simply supported slab. Restraining the horizontal movement at supports may develop the membrane action (MA) in the slab that can remarkably enhance the flexural rigidities of the floor. Experimental tests were conducted along with developing nonlinear finite element model to explore the effect of MA in the PSSDB floor. Experimental results of the PSSDB panel with simply end support were exploited to verify the nonlinear finite element results. The developed finite element model was then modified by restraining the horizontal movement of the slab at the supports. The obtained results disclosed that the developed compressive membrane action enhanced the stiffness of the slab at serviceability load by about 240%

A study on the ethical components of nursing practice (moral distress, ethical sensitivity, ethical decision)

This paper is an applied research in terms of objective and a descriptive research in terms of method. Having prepared the research plan, a questionnaire was designed based on goals and hypotheses of the research and was sent to the statistical universe. Also this paper is a field research in terms of data collection. As regards theoretical bases of the research, library data collection method has been applied. So, the required data has been gathered by referring to the related references, books, libraries and so on. To design a questionnaire and gather the opinions of the statistical universe members, field study method and researcher-made questionnaire have been used. The statistical universe comprises nurses and head of ICU and head nurses of Najmieh Hospital in Tehran. The respondents were selected by random sampling method. Also to estimate sample size, Morgan table was applied. The statistical universe consists of 65 members and according to the table, 56 questionnaires were determined for the research. So 60 questionnaires were sent and 58 ones were returned. Face and content validity of the research tool were approved by experts. The test reliability was estimated 0.777 by calculating Cronbach's alpha coefficient. In this paper, factor analysis based on partial least squares structural equations method has been applied to analyze more important factors and coefficients, estimate independent variables coefficients and even determine effectiveness of each independent variable on each other and determine appropriateness of the questions and their coefficients in explaining the related index. The main result of this paper presents a proper model for the relation of effective variables on nurse performance by using regression model. © IDOSI Publications, 2014

Reproduction and feeding of Buccaneer anchovy (Encrasicholina punctifer) from coastal waters of Qeshm Island, the Persian Gulf

Encrasicholina punctifer is one of the dominant small pelagic and economically most important fishes of the Persian Gulf, especially in Qeshm Island's coastal waters. Specimens of the fish were collected monthly from the fishing area in the coastal waters of Qeshm Island by random sampling method. Investigation on biological parameters of E. punctifer continued from April 2005 to March 2006. E. punctifer is mainly caught by double-boat purse seine in this area. Reproductive studies showed that maturity season of the fish occur in August. The sex ratio fulfill the theoretical 1:1 (P>0.05). L sub(M50) was attained at a total length of 84 mm. The absolute fecundity was estimated at 1217 plus or minus 331. We showed that the species is planktonivore, its diet consisted of a board spectrum of food types, but crustaceans dominated the food with copepods and their eggs, naplius and semi digested copepods constituting 54% of the diet. The next major food groups found in the diet of the fish were Cyanophyceae 21%, Bacillariophyceae 11%, fish egg and scale 6%, Dinophyceae 4%, with Euglenahyceae, Chiorophyta, Dinoflagellates and others items consisting only 4% of the diet. Analysis of monthly variation in the stomach fullness indicated that feeding intensity fluctuated throughout the year, with the highest value in winter. Vacuity Index indicated this species was of semi-voracious appetite fishes

Experimental Study on the Compressive Membrane Action in Profiled Steel Sheet Dry Board (PSSDB) Floor System

This paper describes the experimental work conducted at Universiti Kebangsaan Malaysia to examine the capability of the profiled steel sheet dry board (PSSDB) system to develop the compressive membrane action (CMA) in the floor. The development of the CMA inside the floor is strictly associated with the horizontal movement of the slab end under the vertical loading. Therefore, the simply supported PSSDB floor was tested under vertical uniformly distributed load. Study of results revealed that the recorded horizontal movement at the roller support of the slab is 0.81 mm in the pin- roller supported case. This proves that the PSSDB floor has the potential to develop the CMA under the pin-pin support condition

Teachers' professional development using cyberspace: The phenomenological study of Hamedan teachers

Background and Objective As one of the key components of the curriculum, the teacher has an effective role in teaching effectiveness and facilitating learning. The quality of teachers’ work is the most important factor influencing the quality of students' learning and the success of the educational systems. Teachers, as one of the complex components of the school ecosystem must be able to meet the expectations and demands of various admin administrators and stakeholders and have a deep understanding of social developments and future changes. Therefore, teachers must constantly seek to update their knowledge and skills and improve their professional development. The field of teacher professional development consists of various aspects such as perceptions, educational beliefs, epistemology, ideology, behavior, and practice related to teaching and learning. The present study seeks to investigate how Iranian teachers use cyberspace for their professional development. Methods: In this study, qualitative research method with descriptive phenomenological approach used the subjects, who consist of 25 teachers who actively promote the educational applications of cyberspace, were selected from among the teachers of Hamedan Province and invited to an interview. Snowball sampling technique was used and the number of subjects was decided to be 25 according to the principle of theoretical saturation the reliability and validity of the data were determined by transferability and dependability. Findings: By using information retrieval tools, they can access their required information in various fields, become informed about conferences and educational workshops, rethink their experience as well as improve their self-confidence in responding to students' questions. By using tools content production and presentation, they can produce high-quality multimedia contents, design various learning activities, encourage students to participate in activities, and adopt active teaching methods. Finally, teachers can make use of interactive tools to express their experience and receive feedback, exchange information with other teachers and scholars, improve their communication skills, get involved in participatory learning along with their colleagues and conduct team projects. Conclusion: The findings of this study showed that Iranian teachers use three tools of information retrieval, production and presentation of content and interactive tools to develop themselves professionally with respect to content, pedagogical and technological knowledge. Based on the findings, teachers can use the retriveal tools to find the information they need in a variety of areas, such as information about the field of study and the latest changes in textbooks, information about students' educational issues, teaching methods, evaluation methods, research methods, learning theories, education in other countries as well as time, place and themes of wbinars and conferences. The results also showed that teachers can use interactive tools to express their experiences and use the opinions of others to improve them; create a participatory atmosphere; strengthen their critical thinking; improve their writing skills and promote their skills in using word processors; exchange information with experts and colleagues; strengthen their conversational skills; work with partners and experts on collaborative projects; and design individual and group learning activities. So teachers can use cyberspace as a platform to empower themselves professionally.   ===================================================================================== COPYRIGHTS  ©2020 The author(s). This is an open access article distributed under the terms of the Creative Commons Attribution (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, as long as the original authors and source are cited. No permission is required from the authors or the publishers.  ====================================================================================

Mental health in high-tech system

Stress and mental health at the place of work have received great attention by researchers. In spite of technology improvement in high-tech systems, the operators face new problems, which can affect mental health. There is hardly any published research about stress or mental health in such workplaces in developing countries. This paper presents the application of the self-rating scale General Health Questionnaire (GHQ-28) to study mental health of 160 controllers working in a part of Air Traffic Control (ATC) as a high tech system in Iran. Logistic regression analysis showed that demographic variables did not exhibit a statistically significant effect on scores of the test. In order to compare mental health of these operators with general population, an exposure / non-exposure study was designed. Three age groups (less than 29 years, 30 through 39 y, and more than 40 y) were compared in exposed and non-exposed groups. The results of Fisher’s exact test showed that mental distress symptoms were significantly higher in the exposed group. There were significant job effects on somatization, anxiety and depression as well as on the total score of GHQ-28 for the two first age groups (P<.05). No significant effects of the job were found on social dysfunction symptoms in any age groups. The risk ratio of expressing depression and anxiety symptoms were more than three times greater in these operators than general population

Investigating learning theories in social networks; providing a theoretical framework for curriculum design

Background and Objectives: To use social media effectively, we need to identify and apply the implications of supportive theories using social media. Different learning theories provide a variety of interpretations of learning. Different learning theories lead to diverse orientations and outcomes in curriculum planning. Therefore, learning theories serve as a framework for guiding decisions during the design and implementation of the curriculum. The aim of this study was to identify the types of learning theories that support the use of social networks and to analyze learning theories on social networks in order to provide a theoretical basis for designing curricula. Methods: For this study, qualitative content analysis method was used. The statistical population of this study consists of all valid documents related to the subject- supportive theories of learning in social networks- from 1995 to 2018 (n=30) selected based on purposeful sampling. The content of 30 documents were analyzed.  The analysis unit is the theme. To analyze the findings, the main and sub-classes were extracted after open coding. To ensure the validity of the research, the methods of review by members, triangulation of data sources and review by colleagues were used, and to ensure reliability, the agreement method between the two coders was used. Findings: The findings showed a variety of context-based, community-based, and person-centered theories that support learning on social media. The findings also include four main categories: It showed the dimensions of social networks, network interactions, types of learning, and curriculum elements. It was shown that network communication in social networks includes social interaction, interpersonal communication and interactive communication with admin and teacher-student communication, which is broad and based on community sharing, central agreement and based on sharing ideas. Types of learning on social networks include; network learning, situational learning, problem-based learning, personal learning, and indirect learning. Elements of the curriculum include; network objectives, network content, network learning environment, network inclusiveness, and network evaluation. Network Objectives; features such as unpredictability, divergence, unpredictability, variability, nonlinearity, flexibility, value, reproductive and interactive. Network content has some features such as distributed knowledge, multiplicity of resources, reliable resources, accessibility, context-based knowledge, shared knowledge, inclusive knowledge, self-centered information, voluntary knowledge creation, interchangeable content. The network environment includes technical and educational features. Among the technical features of this environment, we can mention the diversity of language, the existence of communication tools, the possibility of customizing the message and simulating communication. The educational features of this environment also include; being rich is one of the tools of knowledge management, situational awareness, personalized information, open and flexible environment. The network learner is knowledgeable and up-to-date, independent and active, able to do several things together. The network learner is an actor, and social agent who processes, publishes, and manages knowledge on a regular basis. Evaluation on social media is a nonlinear process, formative, conscious, and continuous that is accompanied by the elimination of standard rankings and tests. Conclusion: Based on the research results, it is suggested that those in charge of education use the coordinates of social network-based curriculum elements to design a curriculum based on social networks. For further research it is suggested that researchers implement the findings in an experimental environment to take a positive step towards the optimal use of social networks to learners’ learning outcome.   ===================================================================================== COPYRIGHTS  ©2020 The author(s). This is an open access article distributed under the terms of the Creative Commons Attribution (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, as long as the original authors and source are cited. No permission is required from the authors or the publishers.  ====================================================================================

Commercialization of JPL Virtual Reality calibration and redundant manipulator control technologies

Within NASA's recent thrust for industrial collaboration, JPL (Jet Propulsion Laboratory) has recently established two technology cooperation agreements in the robotics area: one on virtual reality (VR) calibration with Deneb Robotics, Inc., and the other on redundant manipulator control with Robotics Research Corporation (RRC). These technology transfer cooperation tasks will enable both Deneb and RRC to commercialize enhanced versions of their products that will greatly benefit both space and terrestrial telerobotic applications