Teaching Thermodynamics with Physlets[R] in Introductory Physics
ERIC Educational Resources Information Center
Cox, Anne J.; Belloni, Mario; Dancy, Melissa; Christian, Wolfgang
2003-01-01
This paper describes the use of interactive, Physlet[R]-based curricular material designed to help students learn concepts of thermodynamics with a particular focus on the use of kinetic theory models. These exercises help students visualize ideal gas particle dynamics and engine cycles, make concrete connections between mechanics and…
ERIC Educational Resources Information Center
Ülen, Simon; Gerlic, Ivan; Slavinec, Mitja; Repnik, Robert
2017-01-01
To provide a good understanding of many abstract concepts in the field of electricity above that of their students is often a major challenge for secondary school teachers. Many educational researchers promote conceptual learning as a teaching approach that can help teachers to achieve this goal. In this paper, we present Physlet-based materials…
NASA Astrophysics Data System (ADS)
Ülen, Simon; Gerlič, Ivan; Slavinec, Mitja; Repnik, Robert
2017-04-01
To provide a good understanding of many abstract concepts in the field of electricity above that of their students is often a major challenge for secondary school teachers. Many educational researchers promote conceptual learning as a teaching approach that can help teachers to achieve this goal. In this paper, we present Physlet-based materials for supporting conceptual learning about electricity. To conduct research into the effectiveness of these materials, we designed two different physics courses: one group of students, the experimental group, was taught using Physlet-based materials and the second group of students, the control group, was taught using expository instruction without using Physlets. After completion of the teaching, we assessed students' thinking skills and analysed the materials with an independent t test, multiple regression analyses and one-way analysis of covariance. The test scores were significantly higher in the experimental group than in the control group ( p < 0.05). The results of this study confirmed the effectiveness of conceptual learning about electricity with the help of Physlet-based materials.
The Physlet Approach to Simulation Design
ERIC Educational Resources Information Center
Christian, Wolfgang; Belloni, Mario; Esquembre, Francisco; Mason, Bruce A.; Barbato, Lyle; Riggsbee, Matt
2015-01-01
Over the past two years, the AAPT/ComPADRE staff and the Open Source Physics group have published the second edition of "Physlet Physics" and "Physlet Quantum Physics," delivered as interactive web pages on AAPT/ComPADRE and as free eBooks available through iTunes and Google Play. These two websites, and their associated books,…
The Physlet Approach to Simulation Design
NASA Astrophysics Data System (ADS)
Christian, Wolfgang; Belloni, Mario; Esquembre, Francisco; Mason, Bruce A.; Barbato, Lyle; Riggsbee, Matt
2015-10-01
Over the past two years, the AAPT/ComPADRE staff and the Open Source Physics group have published the second edition of Physlet Physics and Physlet Quantum Physics, delivered as interactive web pages on AAPT/ComPADRE and as free eBooks available through iTunes and Google Play. These two websites, and their associated books, add over 1000 interactive exercises for the teaching of introductory physics, introductory and intermediate modern physics, and quantum mechanics to AAPT/ComPADRE.
Teaching Qualitative Energy-Eigenfunction Shape with Physlets
ERIC Educational Resources Information Center
Belloni, Mario; Christian, Wolfgang; Cox, Anne J.
2007-01-01
More than 35 years ago, French and Taylor outlined an approach to teach students and teachers alike how to understand "qualitative plots of bound-state wave functions." They described five fundamental statements based on the quantum-mechanical concepts of probability and energy (total and potential), which could be used to deduce the shape of…
Computer Based Collaborative Problem Solving for Introductory Courses in Physics
NASA Astrophysics Data System (ADS)
Ilie, Carolina; Lee, Kevin
2010-03-01
We discuss collaborative problem solving computer-based recitation style. The course is designed by Lee [1], and the idea was proposed before by Christian, Belloni and Titus [2,3]. The students find the problems on a web-page containing simulations (physlets) and they write the solutions on an accompanying worksheet after discussing it with a classmate. Physlets have the advantage of being much more like real-world problems than textbook problems. We also compare two protocols for web-based instruction using simulations in an introductory physics class [1]. The inquiry protocol allowed students to control input parameters while the worked example protocol did not. We will discuss which of the two methods is more efficient in relation to Scientific Discovery Learning and Cognitive Load Theory. 1. Lee, Kevin M., Nicoll, Gayle and Brooks, Dave W. (2004). ``A Comparison of Inquiry and Worked Example Web-Based Instruction Using Physlets'', Journal of Science Education and Technology 13, No. 1: 81-88. 2. Christian, W., and Belloni, M. (2001). Physlets: Teaching Physics With Interactive Curricular Material, Prentice Hall, Englewood Cliffs, NJ. 3. Christian,W., and Titus,A. (1998). ``Developing web-based curricula using Java Physlets.'' Computers in Physics 12: 227--232.
Physlets and Web-based Physics Curricular Material
NASA Astrophysics Data System (ADS)
Cain, L. S.; Boye, D. M.; Christian, W.
1998-11-01
The WWW provides the most uniformly standardized and stable mode of networked information sharing available to date. Physlets, scriptable Java applets specific to physics pedagogy, provide the source around which interactive exercises can be created across the physics curriculum. We have developed WWW-based curricular materials appropriate for courses at the introductory and intermediate level. These include interactive demonstrations, homework assignments, pre-lab and post-lab exercises. A variety of examples, which have been used in courses in musical technology, general physics, physics for non-science majors, and modern physics, will be discussed.
Emerging Technologies in Physics Education
ERIC Educational Resources Information Center
Krusberg, Zosia A. C.
2007-01-01
Three emerging technologies in physics education are evaluated from the interdisciplinary perspective of cognitive science and physics education research. The technologies--Physlet Physics, the Andes Intelligent Tutoring System (ITS), and Microcomputer-Based Laboratory (MBL) Tools--are assessed particularly in terms of their potential at promoting…
A Comparison of Inquiry and Worked Example Web-Based Instruction Using Physlets
ERIC Educational Resources Information Center
Lee, Kevin M.; Nicoll, Gayle; Brooks, David W.
2004-01-01
This paper compares two protocols for web-based instruction using simulations in an introductory physics class. The Inquiry protocol allowed students to control input parameters while the Worked Example protocol did not. Students in the Worked Example group performed significantly higher on a common assessment. The ramifications of this study are…
NASA Astrophysics Data System (ADS)
Haase, David G.
2009-05-01
When a college instructor goes out of town and must miss a lecture, the standard options are to cancel the class meeting or to enlist a colleague to fill in. In the former case a teaching opportunity is lost; in the latter the substitute may not lead the class in the same way as the instructor. Some students routinely skip lectures by a guest instructor, in the belief that the material in the substitute lecture will not be covered on the exam. There are other makeup options such as a directed study assignment. For instance, a missed class is sometimes a good opportunity to require students to investigate web-based simulations such as Physlets® that illustrate the class topics. These are most effective if the students are given a clear structure and if there are questions that the students must answer from their investigations with the Physlets. But many students are more comfortable with the audio and visual communication that occurs in the classroom. Web 2.0 technology, e.g., YouTube (http://www.youtube.com), makes it convenient for faculty to upload videos of lectures and demonstrations that can be used for makeup classes. College students already use YouTube for entertainment, and the YouTube format is simple to view on any web-connected computer. Although some universities have highly developed media delivery systems, YouTube is extremely convenient and accessible by anyone. This paper discusses how a YouTube makeup class can be efficiently produced and structured to be an effective learning experience.
Online Student Learning and Earth System Processes
NASA Astrophysics Data System (ADS)
Mackay, R. M.
2002-12-01
Many students have difficulty understanding dynamical processes related to Earth's climate system. This is particularly true in Earth System Science courses designed for non-majors. It is often tempting to gloss over these conceptually difficult topics and have students spend more study time learning factual information or ideas that require rather simple linear thought processes. Even when the professor is ambitious and tackles the more difficult ideas of system dynamics in such courses, they are typically greeted with frustration and limited success. However, an understanding of generic system concepts and processes is quite arguably an essential component of any quality liberal arts education. We present online student-centered learning modules that are designed to help students explore different aspects of Earth's climate system (see http://www.cs.clark.edu/mac/physlets/GlobalPollution/maintrace.htm for a sample activity). The JAVA based learning activities are designed to: be assessable to anyone with Web access; be self-paced, engaging, and hands-on; and make use of past results from science education research. Professors can use module activities to supplement lecture, as controlled-learning-lab activities, or as stand-alone homework assignments. Acknowledgement This work was supported by NASA Office of Space Science contract NASW-98037, Atmospheric and Environmental Research Inc. of Lexington, MA., and Clark College.
Writing an Electronic Astronomy Book with Interactive Curricular Material
NASA Astrophysics Data System (ADS)
Thompson, Kristen L.; Belloni, Mario; Christian, Wolfgang
2015-01-01
With the rise of tablets, the past few years have seen an increase in the demand for quality electronic textbooks. Unfortunately, most of the current offerings do not exploit the accessibility and interactivity that electronic books can deliver. In this poster, we discuss how we are merging our curriculum development projects (Physlets, Easy Java/JavaScript Simulations, and Open Source Physics) with the EPUB electronic book format to develop an interactive textbook for use in a one-semester introductory astronomy course. The book, Astronomy: An Interactive Introduction, combines the narrative, equations, and images of a traditional astronomy text with new JavaScript simulations.
ERIC Educational Resources Information Center
Nieminen, Pasi; Savinainen, Antti; Viiri, Jouni
2010-01-01
This study investigates students' ability to interpret multiple representations consistently (i.e., representational consistency) in the context of the force concept. For this purpose we developed the Representational Variant of the Force Concept Inventory (R-FCI), which makes use of nine items from the 1995 version of the Force Concept Inventory…
NASA Astrophysics Data System (ADS)
Buaraphan, Khajornsak
2018-01-01
According to the constructivist theory, students' prior conceptions play an important role in their process of knowledge construction and teachers must take those prior conceptions into account when designing learning activities. The interpretive study was conducted to explore grade 8 students' conceptions about force and motion. The research participants were 42 students (21 male, 21 female) from seven Educational Opportunity Expansion Schools in Nakhon Pathom province located at the central region of Thailand. In each school, two low, two medium and two high achievers were selected. The Interview-About-Instance (IAI) technique was used to collect data. All interviews were audio recorded and subsequently transcribed verbatim. The students' conceptions were interpreted into scientific conception (SC), partial scientific conception (PC) and alternative conception (AC). The frequency of each category was counted and calculated for percentage. The results revealed that the students held a variety of prior conceptions about force and motion ranged from SC, PC to AC. Each students, including the high achievers, held mixed conceptions of force and motion. Interesting, the two dominant ACs held by the students were: a) force-implies-motion or motion-implies-force, and b) force coming only from an active agent. The science teachers need to take these ACs into account when designing the learning activities to cope with them. The implications regarding teaching and learning about force and motion are also discussed.
On the Concept of Force: How Understanding Its History Can Improve Physics Teaching
ERIC Educational Resources Information Center
Coelho, Ricardo Lopes
2010-01-01
Some physicists have pointed out that we do not know what force is. The most common definition of force in textbooks has been criticized for more than two centuries. Many studies have shown that the concept of force is a problem for teaching. How to conceive force on the basis of the concepts and criticism of force in the works of Newton, Euler,…
ERIC Educational Resources Information Center
Fulmer, Gavin W.
2015-01-01
This study examines the validity of 2 proposed learning progressions on the force concept when tested using items from the Force Concept Inventory (FCI). This is the first study to compare students' performance with respect to learning progressions both for force and motion and for Newton's third law in parallel. It is also among the first studies…
Students' Proficiency Scores within Multitrait Item Response Theory
ERIC Educational Resources Information Center
Scott, Terry F.; Schumayer, Daniel
2015-01-01
In this paper we present a series of item response models of data collected using the Force Concept Inventory. The Force Concept Inventory (FCI) was designed to poll the Newtonian conception of force viewed as a multidimensional concept, that is, as a complex of distinguishable conceptual dimensions. Several previous studies have developed…
Inculcating Quality Concepts in the US Air Force: Right Music, Wrong Step
1994-04-01
CONCEPTS IN THE US AIR FORCE: RIGHT MUSIC , WRONG STEP Acceslon For NTIS CRA&J DTIC TAB Unannounced fJ by Justification Barbara A. Kucharczyk By. Lieutenant...TITLE: Inculcating Quality Concepts in the US Air Force: Right Music , Wrong Step AUTHOR: Barbara A. Kucharczyk, Lieutenant Colonel, USAF In its...perceived attitudinal backlash.4 While basic quality concepts are certainly the right music , many Air Force members are dancing the wrong step. Why? This
Integrated Force Method Solution to Indeterminate Structural Mechanics Problems
NASA Technical Reports Server (NTRS)
Patnaik, Surya N.; Hopkins, Dale A.; Halford, Gary R.
2004-01-01
Strength of materials problems have been classified into determinate and indeterminate problems. Determinate analysis primarily based on the equilibrium concept is well understood. Solutions of indeterminate problems required additional compatibility conditions, and its comprehension was not exclusive. A solution to indeterminate problem is generated by manipulating the equilibrium concept, either by rewriting in the displacement variables or through the cutting and closing gap technique of the redundant force method. Compatibility improvisation has made analysis cumbersome. The authors have researched and understood the compatibility theory. Solutions can be generated with equal emphasis on the equilibrium and compatibility concepts. This technique is called the Integrated Force Method (IFM). Forces are the primary unknowns of IFM. Displacements are back-calculated from forces. IFM equations are manipulated to obtain the Dual Integrated Force Method (IFMD). Displacement is the primary variable of IFMD and force is back-calculated. The subject is introduced through response variables: force, deformation, displacement; and underlying concepts: equilibrium equation, force deformation relation, deformation displacement relation, and compatibility condition. Mechanical load, temperature variation, and support settling are equally emphasized. The basic theory is discussed. A set of examples illustrate the new concepts. IFM and IFMD based finite element methods are introduced for simple problems.
Central Distractors in Force Concept Inventory Data
ERIC Educational Resources Information Center
Scott, Terry F.; Schumayer, Dániel
2018-01-01
The Force Concept Inventory was designed to poll the Newtonian conception of force. While there are many in-depth studies analyzing response data that look at the structure of the correct answers, we believe that the incorrect answers also carry revealing information about the students' worldview. The inventory was originally designed so that the…
Research on the comparison of performance-based concept and force-based concept
NASA Astrophysics Data System (ADS)
Wu, Zeyu; Wang, Dongwei
2011-03-01
There are two ideologies about structure design: force-based concept and performance-based concept. Generally, if the structure operates during elastic stage, the two philosophies usually attain the same results. But beyond that stage, the shortage of force-based method is exposed, and the merit of performance-based is displayed. Pros and cons of each strategy are listed herein, and then which structure is best suitable to each method analyzed. At last, a real structure is evaluated by adaptive pushover method to verify that performance-based method is better than force-based method.
ERIC Educational Resources Information Center
Martin-Blas, Teresa; Seidel, Luis; Serrano-Fernandez, Ana
2010-01-01
This work presents the results of a study whose aim is to detect systematic errors about the concept of force among freshmen students. The researchers analysed the results of the Force Concept Inventory test, which was administered to two different groups of students. The results show that, although there were significant performance variations…
Conceptual Coherence of Non-Newtonian Worldviews in Force Concept Inventory Data
ERIC Educational Resources Information Center
Scott, Terry F.; Schumayer, Dániel
2017-01-01
The Force Concept Inventory is one of the most popular and most analyzed multiple-choice concept tests used to investigate students' understanding of Newtonian mechanics. The correct answers poll a set of underlying Newtonian concepts and the coherence of these underlying concepts has been found in the data. However, this inventory was constructed…
On the Concept of Force: A Comment on Lopes Coelho
ERIC Educational Resources Information Center
Kalman, Calvin S.
2011-01-01
This article presents a supplement to Coelho's excellent article concerning the definition of force by first defining mass and then momentum. Replacing force with the concept of a field is also briefly noted.
Time Critical Targeting Concept of Operations (CONOPS) Interactions
2011-05-01
range of topics in force development and employment. Carl has participated in projects examining the interdiction of armoured ground forces , long...Critical Targeting Concept of Operations (CONOPS) Interactions Executive Summary In 2003, RAND Project Air Force examined the...Attack. ____________________ ________________________________________________ Carl Rhodes Project Air Force , RAND Corporation Carl Rhodes is the
Conceptual Problems in the Foundations of Mechanics
NASA Astrophysics Data System (ADS)
Coelho, Ricardo Lopes
2012-09-01
There has been much research on principles and fundamental concepts of mechanics. Problems concerning the law of inertia, the concepts of force, fictitious force, weight, mass and the distinction between inertial and gravitational mass are addressed in the first part of the present paper. It is argued in the second that the law of inertia is the source of these problems. Consequences drawn from the law explain the metaphysical concept of force, the problematic concept of fictitious force, the nominal definition of weight and the difficulty with defining mass operationally. The core of this connection between the law and these consequences lies in the fact that acceleration is a sufficient condition for force. The experimental basis of the law in the course of its history shows, however, that the law presupposes acceleration necessarily whereas acceleration does not presuppose the law. Therefore, there is no inconvenience in taking acceleration independently of the law. This is enough to bypass those problems. Taking into account how force is measured by force meters and how mass is basically determined, by comparison with the standard mass, a minimal meaning for both concepts of force and mass is established. All this converges with several solutions proposed in the course of history and increases the communicability of mechanics, as outlined in the final part of this paper.
ERIC Educational Resources Information Center
Vallett, David Bruce
2013-01-01
This study examined the relationships among visuospatial ability, motivation to learn science, and learner conceptions of force across commonly measured demographics with university undergraduates with the aim of examining the support for an evolved sense of force and motion. Demographic variables of interest included age, ethnicity, and gender,…
Unified Technical Concepts. Module 8: Force Transformers.
ERIC Educational Resources Information Center
Technical Education Research Center, Waco, TX.
This concept module on force transformers is one of thirteen modules that provide a flexible, laboratory-based physics instructional package designed to meet the specialized needs of students in two-year, postsecondary technical schools. Each of the thirteen concept modules discusses a single physics concept and how it is applied to each energy…
Unified Technical Concepts. Module 1: Force.
ERIC Educational Resources Information Center
Technical Education Research Center, Waco, TX.
This concept module on force is one of thirteen modules that provide a flexible, laboratory-based physics instructional package designed to meet the specialized needs of students in two-year, postsecondary technical schools. Each of the thirteen concept modules discusses a single physics concept and how it is applied to each energy system. This…
ERIC Educational Resources Information Center
Joung, Yong Jae; Gunstone, Richard
2010-01-01
Typically-Perceived-Situation (TPS) refers to the situation rising spontaneously in an individual's mind when she/he first thinks of a phenomenon or concept. The purpose of this study is to go well beyond the many studies that describe conceptions of force and explore children's TPS of "force is acting on a thing" and "force is not…
ERIC Educational Resources Information Center
Fulmer, Gavin W.; Liang, Ling L.; Liu, Xiufeng
2014-01-01
This exploratory study applied a proposed force and motion learning progression (LP) to high-school and university students and to content involving both one- and two-dimensional force and motion situations. The Force Concept Inventory (FCI) was adapted, based on a previous content analysis and coding of the questions in the FCI in terms of the…
The Road to Information Dominance: "System of Systems" Concept for the United States Armed Forces.
1998-04-06
information dominance through the U.S. Armed Forces "System of Systems" concept. It addresses and analyzes current and future strategic implications and requirements for U.S. warfighting communications and information systems. It proposes a more flexible, reliable, responsive, robust and survivable high capacity throughput communications and "bitways" system to support future force projection operations for the Force and/or Army After Next. Lastly, it concludes with a suggested methodology to implement the "System of Systems" concept to enable
Bioplasmic Forces: A New Concept of Readiness
ERIC Educational Resources Information Center
Ogletree, Earl J.
1973-01-01
Discusses the concept of bioplasmic forces--the foundation of human growth, regeneration of cells, and life energy--and the relationship between physical and mental development of the child, focusing on the theory that premature or forced learning may cause intellectual or academic retardation. (TO)
NASA Astrophysics Data System (ADS)
Nieminen, Pasi; Savinainen, Antti; Viiri, Jouni
2010-07-01
This study investigates students’ ability to interpret multiple representations consistently (i.e., representational consistency) in the context of the force concept. For this purpose we developed the Representational Variant of the Force Concept Inventory (R-FCI), which makes use of nine items from the 1995 version of the Force Concept Inventory (FCI). These original FCI items were redesigned using various representations (such as motion map, vectorial and graphical), yielding 27 multiple-choice items concerning four central concepts underpinning the force concept: Newton’s first, second, and third laws, and gravitation. We provide some evidence for the validity and reliability of the R-FCI; this analysis is limited to the student population of one Finnish high school. The students took the R-FCI at the beginning and at the end of their first high school physics course. We found that students’ (n=168) representational consistency (whether scientifically correct or not) varied considerably depending on the concept. On average, representational consistency and scientifically correct understanding increased during the instruction, although in the post-test only a few students performed consistently both in terms of representations and scientifically correct understanding. We also compared students’ (n=87) results of the R-FCI and the FCI, and found that they correlated quite well.
ERIC Educational Resources Information Center
Maries, Alexandru; Singh, Chandralekha
2016-01-01
The Force Concept Inventory (FCI) has been widely used to assess student understanding of introductory mechanics concepts by a variety of educators and physics education researchers. One reason for this extensive use is that many of the items on the FCI have strong distractor choices which correspond to students' alternate conceptions in…
ERIC Educational Resources Information Center
Nieminen, Pasi; Savinainen, Antti; Viiri, Jouni
2012-01-01
Previous physics education research has raised the question of "hidden variables" behind students' success in learning certain concepts. In the context of the force concept, it has been suggested that students' reasoning ability is one such variable. Strong positive correlations between students' preinstruction scores for reasoning…
Experimentally Building a Qualitative Understanding of Newton's Second Law
NASA Astrophysics Data System (ADS)
Gates, Joshua
2014-12-01
Newton's second law is one of the cornerstones of the introductory physics curriculum, but it can still trouble a large number of students well after its introduction, hobbling their ability to apply the concept to problem solving1 and to related concepts, such as momentum, circular motion, and orbits. While there are several possibilities for lab activities addressing the functional relationship among net force, mass, and acceleration, the qualitative understanding of the connection between forces and acceleration can still be lacking,2 leading to poor performance in problem solving and in assessments such as the Force Concept Inventory3 and Force and Motion Conceptual Evaluation.4 There is a need for strong conceptual understanding of the relationships between net force and acceleration and between acceleration and velocity in order to effectively address common force-motion misconceptions;5 there is a large literature concerning student understanding of force and motion.6
The electromigration force in metallic bulk
NASA Astrophysics Data System (ADS)
Lodder, A.; Dekker, J. P.
1998-01-01
The voltage induced driving force on a migrating atom in a metallic system is discussed in the perspective of the Hellmann-Feynman force concept, local screening concepts and the linear-response approach. Since the force operator is well defined in quantum mechanics it appears to be only confusing to refer to the Hellmann-Feynman theorem in the context of electromigration. Local screening concepts are shown to be mainly of historical value. The physics involved is completely represented in ab initio local density treatments of dilute alloys and the implementation does not require additional precautions about screening, being typical for jellium treatments. The linear-response approach is shown to be a reliable guide in deciding about the two contributions to the driving force, the direct force and the wind force. Results are given for the wind valence for electromigration in a number of FCC and BCC metals, calculated using an ab initio KKR-Green's function description of a dilute alloy.
Revitalizing the Physics Department: The Use of Interactive Technologies to Improve Student Learning
NASA Astrophysics Data System (ADS)
Sheldon, Peter; Groover, Holly
2002-04-01
The Physics Department at Randolph-Macon Woman's College, a liberal arts women's college of 720, has traditionally turned out approximately 0.6 majors/year. We have invigorated the program by adding community (e.g. SPS, physical space, organized activities), adding a significant technical component (e.g. web-assisted and computerized labs and more technology in the classes [1]), and incorporating new learning techniques (JITT, Physlets, Peer Instruction and Cooperative Learning [2]). Students have responded well as evidenced by significant increases in enrollments as well as strong scores on the FCI. We have seen mixed results in the lab, but increased performance in the class, which is attributed to the interactive learning techniques that are being implemented through new technologies. In this presentation, we will discuss the implementation of the new curricular developments and the specific changes we have seen in student learning. [1] This work is supported in part by the NSF CCLI Program under grant DUE-9980890. Additional support has been from the Virginia Foundation of Private Colleges and AT&T. [2] See, for example, the project Galileo website http://galileo.harvard.edu for a description of all of these techniques.
NASA Astrophysics Data System (ADS)
Bykov, Tikhon
2010-03-01
In recent years McMurry University's introductory physics curriculum has gone through a series of significant changes to achieve better integration of traditional course components (lecture/lab/discussion) by means of instructional design and technology. A system of flexible curriculum modules with emphasis on inquiry-based teaching and collaborative active learning has been introduced. To unify module elements, a technology suite has been used that consists of Tablet PC's and software applications including Physlets, tablet-adapted personal response system, PASCO data acquisition systems, and MS One-note collaborative writing software. Adoption of the new teaching model resulted in reevaluation of existing instructional spaces. The new teaching space will be created during the renovation of the McMurry Science Building. This space will allow for easy transitions between lecture and laboratory modes. Movable partitions will be used to accommodate student groups of different sizes. The space will be supportive of small peer-group activities with easy-to-reconfigure furniture, multiple white and black board surfaces and multiple projection screens. The new space will be highly flexible to account for different teaching functions, different teaching modes and learning styles.
Interference between Electric and Magnetic Concepts in Introductory Physics
ERIC Educational Resources Information Center
Scaife, Thomas M.; Heckler, Andrew F.
2011-01-01
We investigate student confusion of concepts of electric and magnetic force. At various times during a traditional university-level course, we administered a series of simple questions about the direction of force on a charged particle moving through either an electric or a magnetic field. We find that after electric force instruction but before…
The effect of force feedback on student reasoning about gravity, mass, force and motion
NASA Astrophysics Data System (ADS)
Bussell, Linda
The purpose of this study was to examine whether force feedback within a computer simulation had an effect on reasoning by fifth grade students about gravity, mass, force, and motion, concepts which can be difficult for learners to grasp. Few studies have been done on cognitive learning and haptic feedback, particularly with young learners, but there is an extensive base of literature on children's conceptions of science and a number of studies focus specifically on children's conceptions of force and motion. This case study used a computer-based paddleball simulation with guided inquiry as the primary stimulus. Within the simulation, the learner could adjust the mass of the ball and the gravitational force. The experimental group used the simulation with visual and force feedback; the control group used the simulation with visual feedback but without force feedback. The proposition was that there would be differences in reasoning between the experimental and control groups, with force feedback being helpful with concepts that are more obvious when felt. Participants were 34 fifth-grade students from three schools. Students completed a modal (visual, auditory, and haptic) learning preference assessment and a pretest. The sessions, including participant experimentation and interviews, were audio recorded and observed. The interviews were followed by a written posttest. These data were analyzed to determine whether there were differences based on treatment, learning style, demographics, prior gaming experience, force feedback experience, or prior knowledge. Work with the simulation, regardless of group, was found to increase students' understanding of key concepts. The experimental group appeared to benefit from the supplementary help that force feedback provided. Those in the experimental group scored higher on the posttest than those in the control group. The greatest difference between mean group scores was on a question concerning the effects of increased gravitational force.
NASA Astrophysics Data System (ADS)
Rosiek, Roman; Sajka, Mirosława; Ohno, Eizo; Shimojo, Atsushi; Iwata, Michiru; Wcisło, Dariusz
2017-01-01
The paper presents the initial results of a comparative Polish-Japanese study. The research was conducted at the Department of Mathematics, Physics and Technical Science at the Pedagogical University of Cracow and at the University of Hokkaido. The participants of the study were university students of humanistic courses. The research concerns the comparison of the respondents' knowledge and understanding of the concept of force in mechanics and their ways of solving problems in the field of a basic mechanics course. A special theoretical tool was used. It was the standardized, international test diagnosing the understanding of the concept of force - the so-called "Force Concept Inventory" (FCI), in its official Polish and Japanese translations. The eye-tracking method was combined with structured interviews and discussions with all the respondents.
ERIC Educational Resources Information Center
Ozdemir, Gokhan
2017-01-01
Students' alternative conceptions of force are one of the most studied topics, important for both science assessment and instruction. Previous studies often described students' alternative conceptions of force with a small number of well-known frameworks by utilizing interviews and paper-pencil tests in their assessments. This study aims to…
Experimental Validation of the Half-Length Force Concept Inventory
ERIC Educational Resources Information Center
Han, Jing; Koenig, Kathleen; Cui, Lili; Fritchman, Joseph; Li, Dan; Sun, Wanyi; Fu, Zhao; Bao, Lei
2016-01-01
In a recent study, the 30-question Force Concept Inventory (FCI) was theoretically split into two 14-question "half-length" tests (HFCIs) covering the same set of concepts and producing mean scores that can be equated to those of the original FCI. The HFCIs require less administration time and reduce test-retest issues when different…
Examining Evolving Performance on the Force Concept Inventory Using Factor Analysis
ERIC Educational Resources Information Center
Semak, M. R.; Dietz, R. D.; Pearson, R. H.; Willis, C. W
2017-01-01
The application of factor analysis to the "Force Concept Inventory" (FCI) has proven to be problematic. Some studies have suggested that factor analysis of test results serves as a helpful tool in assessing the recognition of Newtonian concepts by students. Other work has produced at best ambiguous results. For the FCI administered as a…
Prospective Physics Teachers' Level of Understanding Energy, Power and Force Concepts
ERIC Educational Resources Information Center
Saglam-Arslan, Aysegul; Kurnaz, Mehmet Altan
2009-01-01
The aim of this study is to determine prospective physics teachers' level of understanding of the concepts of energy and the related concepts of force and power. The study was carried out with the participation of 56 physics education department students at a university in Karadeniz region. All participants had previously taken an introductory…
Language Negotiations Indigenous Students Navigate when Learning Science
ERIC Educational Resources Information Center
Chigeza, Philemon
2008-01-01
This paper reports on implications of a research study with a group of 44 Indigenous middle school students learning the science concepts of energy and force. We found the concepts of energy and force need to be taught in English as we failed to find common comparable abstract concepts in the students' diverse Indigenous languages. Three…
Spring roll dielectric elastomer actuators for a portable force feedback glove
NASA Astrophysics Data System (ADS)
Zhang, Rui; Lochmatter, Patrick; Kunz, Andreas; Kovacs, Gabor
2006-03-01
Miniature spring roll dielectric elastomer actuators for a novel kinematic-free force feedback concept were manufactured and experimentally characterized. The actuators exhibited a maximum blocking force of 7.2 N and a displacement of 5 mm. The theoretical considerations based on the material's incompressibility were discussed in order to estimate the actuator behavior under blocked-strain activation and free-strain activation. One prototype was built for the demonstration of the proposed force feedback concept.
Validating Two Questions in the Force Concept Inventory with Subquestions
ERIC Educational Resources Information Center
Yasuda, Jun-ichiro; Taniguchi, Masa-aki
2013-01-01
In this study, we evaluate the structural validity of Q.16 and Q.7 in the Force Concept Inventory (FCI). We address whether respondents who answer Q.16 and Q.7 correctly actually have an understanding of the concepts of physics tested in the questions. To examine respondents' levels of understanding, we use subquestions that test them on concepts…
ERIC Educational Resources Information Center
Normandeau, Magdalen; Iyengar, Seshu; Newling, Benedict
2017-01-01
Concept inventories (CI) are validated, research-based, multiple-choice tests, which are widely used to assess the effectiveness of pedagogical practices in bringing about conceptual change. In order to be a useful diagnostic tool, a CI must reflect only the student understanding of the conceptual material. The Force Concept Inventory (FCI) is…
Magnetic suspension actuator concepts and applications
NASA Technical Reports Server (NTRS)
Kroeger, John
1993-01-01
The fundamental aspect which makes magnetic suspension systems possible is the magnetic phenomena by which significant forces can be generated. Each of these force-producing phenomena has unique characteristics and is implementable in a unique fashion, such that each performs the magnetic suspension task differently than the others. A practical overview of the force-producing concepts, their unique characteristics, and their typical methods of application is provided.
Expanding the MEU(SOC) Joint Task Force Enabler Concept
1998-05-28
concept. 2 The influential twentieth-century linguistic philosopher Ludwig Wittgenstein argued that real understanding rests on the precise use...of language and universally agreed upon meanings. Without clarity and common understanding, Wittgenstein observed, we can never really communicate... Wittgenstein anticipated when we don’t share a common understanding of what a term means. The Joint Task Force Enabler is potentially a critical concept, both
Training-Based Requirements for Semi-Automated Forces
1999-03-01
ARI Research Note 99-18 Training-based Requirements for Semi-Automated Forces Jim Kornell Syukhtun Research, Inc. Research and Advanced Concepts ... Concepts , Inc.; Dr. Susan Fischer, of Anacapa Sciences, Inc.; and Lt. Col. Ken Bell, ret., of THETA Technologies, Inc. All conclusions and...construed) in terms of symbols and concepts , and/or the learning of procedural knowledge. • Cognitive strategies. Skills for governing thinking. This
Basic Combat Unit of the Slovenian Armed Forces
2017-06-09
research offers a review of relevant Slovenian strategic documents, a combined arms concept and the last major U.S. Army transformation that saw the...Armed forces should be. Findings, with other recommendations, should be the foundation for the upcoming transformation of the Slovenian Armed...arms concept and the last major U.S. Army transformation that saw the organization transition from a division to a brigade-centric force. The goal
Report of the Panel on Tactical Aircraft
1968-07-01
i. The Department of the Air Force and the Department of the Navy should be requested to prepare "white papers " on aircraft/ strike concepts that...countermeasures; expand exploratory develop- ment, e. Evaluation of penetration aids; call for concept papers , f. Combat data; develop flight recorders...the Navy and the Department of the Air Force to prepare "white papers " on comprehensive aircraft penetration/ strike concepts that include explicit
The Use of Force Sensors and a Computer System to Introduce the Concept of Inertia at a School
ERIC Educational Resources Information Center
Bogacz, Bogdan F.; Pedziwiatr, Antoni T.
2014-01-01
A classical experiment used to introduce the concept of body inertia, breaking of a thread below and above a hanging weight, is described mathematically and presented in a new way, using force sensors and a computer system.
Stark, C; Nikopoulou-Smyrni, P; Stabrey, A; Semler, O; Schoenau, E
2010-06-01
The purpose of this study was to determine the effect of a new physiotherapy concept on bone density, muscle force and motor function in bilateral spastic cerebral palsy children. In a retrospective data analysis 78 children were analysed. The concept included whole body vibration, physiotherapy, resistance training and treadmill training. The concept is structured in two in-patient stays and two periods of three months home-based vibration training. Outcome measures were dual-energy x-ray absorption (DXA), Leonardo Tilt Table and a modified Gross Motor Function Measure before and after six months of training. Percent changes were highly significant for bone mineral density, -content, muscle mass and significant for angle of verticalisation, muscle force and modified Gross Motor Function Measure after six months training. The new physiotherapy concept had a significant effect on bone mineral density, muscle force and gross motor function in bilateral spastic cerebral palsy children. This implicates an amelioration in all International Classification of Functioning, Disability and Health levels. The study serves as a basis for future research on evidence based paediatric physiotherapy taking into account developmental implications.
ERIC Educational Resources Information Center
Creswell, William H., Jr.; And Others
The following resource guide is one in a series which presents extensive bibliographic material oriented around a specific concept, in this guide, forces affecting personal health practices. A section is devoted to selected materials related to the concept; grade levels for which each resource might be useful are indicated beside each citation. A…
NASA Astrophysics Data System (ADS)
Sheldon, Peter; Wellington, Tracey
2003-03-01
The Physics Department at Randolph-Macon Woman's College, a liberal arts women's college of 720, has traditionally turned out approximately 0.6 majors/year. We have invigorated the program by adding community (e.g. SPS, physical space, organized activities), adding a significant technical component (e.g. web-assisted and computer interfaced labs and more technology in the classes [1]), and incorporating new learning techniques (JITT, Physlets, Peer Instruction [2], Interactive DVD's, and using the Personal Response System [3]). Students have responded well as evidenced by significant increases in enrollments as well as strong scores on the FCI. As an offshoot of this original project supported by the NSF, we have applied some of these teaching methods to teach younger children and teachers of younger children. In this presentation, we will discuss the implementation of the new curricular developments and the specific changes we have seen and hope to see in student learning. [1] This work is supported in part by the NSF CCLI Program under grant DUE-9980890. [2] See, for example, the project Galileo website http://galileo.harvard.edu for a description of all of these techniques. [3] The Personal Response System is a wireless response system made by Educue, www.educue.com.
Students' Development of Representational Competence through the Sense of Touch
ERIC Educational Resources Information Center
Magana, Alejandra J.; Balachandran, Sadhana
2017-01-01
Electromagnetism is an umbrella encapsulating several different concepts like electric current, electric fields and forces, and magnetic fields and forces, among other topics. However, a number of studies in the past have highlighted the poor conceptual understanding of electromagnetism concepts by students even after instruction. This study aims…
NASA Astrophysics Data System (ADS)
Caballero, Marcos D.; Greco, Edwin F.; Murray, Eric R.; Bujak, Keith R.; Jackson Marr, M.; Catrambone, Richard; Kohlmyer, Matthew A.; Schatz, Michael F.
2012-07-01
The performance of over 5000 students in introductory calculus-based mechanics courses at the Georgia Institute of Technology was assessed using the Force Concept Inventory (FCI). Results from two different curricula were compared: a traditional mechanics curriculum and the Matter & Interactions (M&I) curriculum. Both were taught with similar interactive pedagogy. Post-instruction FCI averages were significantly higher for the traditional curriculum than for the M&I curriculum; the differences between curricula persist after accounting for factors such as pre-instruction FCI scores, grade point averages, and SAT scores. FCI performance on categories of items organized by concepts was also compared; traditional averages were significantly higher in each concept. We examined differences in student preparation between the curricula and found that the relative fraction of homework and lecture topics devoted to FCI force and motion concepts correlated with the observed performance differences. Concept inventories, as instruments for evaluating curricular reforms, are generally limited to the particular choice of content and goals of the instrument. Moreover, concept inventories fail to measure what are perhaps the most interesting aspects of reform: the non-overlapping content and goals that are not present in courses without reform.
Regionally Aligned Forces: Concept Viability and Implementation
2015-03-01
forced the Army to accelerate cuts scheduled to occur by the end of FY15.5 While acceleration provides short term savings, projected cuts will affect...Concept Viability and Implementation 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER...mitigate the effects of reduced budgets, the Army will continue to reduce its overall end strength. Reduction initiatives will require the force to be
Concept for room temperature single-spin tunneling force microscopy with atomic spatial resolution
NASA Astrophysics Data System (ADS)
Payne, Adam
A study of a force detected single-spin magnetic resonance measurement concept with atomic spatial resolution is presented. The method is based upon electrostatic force detection of spin-selection rule controlled single electron tunneling between two electrically isolated paramagnetic states. Single-spin magnetic resonance detection is possible by measuring the force detected tunneling charge noise on and off spin resonance. Simulation results of this charge noise, based upon physical models of the tunneling and spin physics, are directly compared to measured atomic force microscopy (AFM) system noise. The results show that the approach could provide single-spin measurement of electrically isolated defect states with atomic spatial resolution at room temperature.
NASA Astrophysics Data System (ADS)
Payne, A.; Ambal, K.; Boehme, C.; Williams, C. C.
2015-05-01
A study of a force detected single-spin magnetic resonance measurement concept with atomic spatial resolution is presented. The method is based upon electrostatic force detection of spin-selection rule controlled single-electron tunneling between two electrically isolated paramagnetic states. Single-spin magnetic resonance detection is possible by measuring the force detected tunneling charge noise on and off spin resonance. Simulation results of this charge noise, based upon physical models of the tunneling and spin physics, are directly compared to measured atomic force microscopy system noise. The results show that the approach could provide single-spin measurement of electrically isolated qubit states with atomic spatial resolution at room temperature.
Rasch Model Based Analysis of the Force Concept Inventory
ERIC Educational Resources Information Center
Planinic, Maja; Ivanjek, Lana; Susac, Ana
2010-01-01
The Force Concept Inventory (FCI) is an important diagnostic instrument which is widely used in the field of physics education research. It is therefore very important to evaluate and monitor its functioning using different tools for statistical analysis. One of such tools is the stochastic Rasch model, which enables construction of linear…
Uncovering the Hidden Meaning of Cross-Curriculum Comparison Results on the Force Concept Inventory
ERIC Educational Resources Information Center
Ding, Lin; Caballero, Marcos D.
2014-01-01
In a recent study, Caballero and colleagues conducted a large-scale evaluation using the Force Concept Inventory (FCI) to compare student learning outcomes between two introductory physics curricula: the Matter and Interactions (M&I) mechanics course and a pedagogically-reformed-traditional-content (PRTC) mechanics course. Using a conventional…
Bioliteracy and Teaching Efficacy: What Biologists Can Learn from Physicists
ERIC Educational Resources Information Center
Klymkowsky, Michael W.; Garvin-Doxas, Kathy; Zeilik, Michael
2003-01-01
The introduction of the Force Concept Inventory (FCI) by David Hestenes and colleagues in 1992 produced a remarkable impact within the community of physics teachers. An instrument to measure student comprehension of the Newtonian concept of force, the FCI demonstrates that active learning leads to far superior student conceptual learning than…
ERIC Educational Resources Information Center
Yuruk, Nejla; Beeth, Michael E.; Andersen, Christopher
2009-01-01
This study investigated the effect of metaconceptual teaching interventions on students' understanding of force and motion concepts. A multimethod research design including quasi-experimental design and case study designs was employed to compare the effect of the metaconceptual activities and traditional instruction and investigate students'…
Context Sensitivity in the Force Concept Inventory
ERIC Educational Resources Information Center
Stewart, John; Griffin, Heather; Stewart, Gay
2007-01-01
The force concept inventory and a 10-question context-modified test were given to 647 students enrolled in introductory physics classes at the University of Arkansas. Context changes had an effect ranging from -3% to 10% on the individual questions. The average student score on the ten transformed questions was 3% higher than the average student…
Gender Fairness within the Force Concept Inventory
ERIC Educational Resources Information Center
Traxler, Adrienne; Henderson, Rachel; Stewart, John; Stewart, Gay; Papak, Alexis; Lindell, Rebecca
2018-01-01
Research on the test structure of the Force Concept Inventory (FCI) has largely ignored gender, and research on FCI gender effects (often reported as "gender gaps") has seldom interrogated the structure of the test. These rarely crossed streams of research leave open the possibility that the FCI may not be structurally valid across…
NASA Astrophysics Data System (ADS)
Harlow, Jason J. B.; Harrison, David M.; Meyertholen, Andrew
2014-06-01
We have studied the correlation of student performance in a large first year university physics course with their reasons for taking the course and whether or not the student took a senior-level high school physics course. Performance was measured both by the Force Concept Inventory and by the grade on the final examination. Students who took the course primarily for their own interest outperformed students who took the course primarily because it was required, both on the Force Concept Inventory and on the final examination; students who took a senior-level high school physics course outperformed students who did not, also both on the Force Concept Inventory and on the final exam. Students who took the course for their own interest and took high school physics outperformed students who took the course because it was required and did not take high school physics by a wide margin. However, the normalized gain on the Force Concept Inventory was the same within uncertainties for all groups and subgroups of students.
Transformations de phases dans les alliages forcés: Un concept utile pour les études d'usure
NASA Astrophysics Data System (ADS)
Chaffron, Laurent; Le Bouar, Yann; Martin, Georges
2001-07-01
The concept of driven alloys is introduced and examples are given for alloys under irradiation or under high energy ball milling. Both real and computer experiments show that the stationary configuration of alloys under external forcing depends on the overall temperature, on the ratio of the ballistic to the thermally activated atomic jump frequency, and on the space and time correlation of the ballistic jumps. As well as temperature, the description of driven phase transformations requires a new control parameter: the intensity of forcing. The latter is shown to be the irradiation flux for alloys under irradiation and the momentum transferred per unit time to an elementary volume of matter, under milling. We show how to use these concepts to address the wear rate of swift train wheels (TGV): it is found that the wear rate is proportional to the intensity of forcing.
NASA Astrophysics Data System (ADS)
Kim, Gi-Woo; Wang, K. W.
2008-03-01
In recent years, researchers have investigated the feasibility of utilizing piezoelectric-hydraulic pump based actuation systems for automotive transmission controls. This new concept could eventually reduce the complexity, weight, and fuel consumption of the current transmissions. In this research, we focus on how to utilize this new approach on the shift control of automatic transmissions (AT), which generally requires pressure profiling for friction elements during the operation. To illustrate the concept, we will consider the 1--> 2 up shift control using band brake friction elements. In order to perform the actuation force tracking for AT shift control, nonlinear force feedback control laws are designed based on the sliding mode theory for the given nonlinear system. This paper will describe the modeling of the band brake actuation system, the design of the nonlinear force feedback controller, and simulation and experimental results for demonstration of the new concept.
2012-04-18
of Employment. Official Message. (CMC WASHINGTON DC PPO POE), DTG: 291447Z Mar 2010. 28 Military Sealift Command, Combat Logistics Force Webpage...Ammunition Ship (F-AKE) Concept of Employment. Official Message. (CMC WASHINGTON DC PPO POE), DTG: 291447Z Mar 2010. 28 30 Headquarters u.s. Marine Corps...Maritime Prepositioning Force (MPF) Auxiliary Dry Cargo/Ammunition Ship (I’-AKE) Concept of Employment. Official Message. (CMC WASHINGTON DC PPO POE
1994-07-27
of the split-flow and recirculation modifications in typical Air Force painting operations; itwas a proof-of- concept study only. It is recognized...recirculating ventilation. 4 To Implement this flow-reduction concept , it must first be established that recirculation does not cause an accumulation of toxic...ventilation concept . The concentration gradient is determined by height and direction of paint application. If the concentration in the top portion is
The Development of the Concept of Work: A Case where History Can Inform Pedagogy
NASA Astrophysics Data System (ADS)
de Berg, Kevin C.
An historical analysis of the work concept with particular emphasis given to the contributions of John Smeaton and Daniel Bernouilli is provided with a view to enlightening or resolving current difficulties experienced in the teaching and learning of the concept of work and its relationship to kinetic and potential energies. An approach which emphasises the work done by both applied and resisting forces and which gives some technological significance to the (force x distance) definition of work is recommended.
Inservice Elementary and Middle School Teachers' Conceptions of Photosynthesis and Respiration
ERIC Educational Resources Information Center
Krall, Rebecca McNall; Lott, Kimberly H.; Wymer, Carol L.
2009-01-01
The purpose of this descriptive study was to investigate inservice elementary and middle school teachers' conceptions of photosynthesis and respiration, basic concepts they are expected to teach. A forced-choice instrument assessing selected standards-based life science concepts with non-scientific conceptions embedded in distracter options was…
Conceptual Problems in the Foundations of Mechanics
ERIC Educational Resources Information Center
Coelho, Ricardo Lopes
2012-01-01
There has been much research on principles and fundamental concepts of mechanics. Problems concerning the law of inertia, the concepts of force, fictitious force, weight, mass and the distinction between inertial and gravitational mass are addressed in the first part of the present paper. It is argued in the second that the law of inertia is the…
ERIC Educational Resources Information Center
Megalakaki, Olga; Thibaut, Jean Pierre
2016-01-01
We looked at how far students aged 10-17 years differentiate between the "force" and "energy" concepts for animates and inanimates. Within a structured interview format, participants described situations in which inanimate objects and animate agents interacted. Results showed that the younger students made no distinction…
A Computer-Controlled Classroom Model of an Atomic Force Microscope
ERIC Educational Resources Information Center
Engstrom, Tyler A.; Johnson, Matthew M.; Eklund, Peter C.; Russin, Timothy J.
2015-01-01
The concept of "seeing by feeling" as a way to circumvent limitations on sight is universal on the macroscopic scale--reading Braille, feeling one's way around a dark room, etc. The development of the atomic force microscope (AFM) in 1986 extended this concept to imaging in the nanoscale. While there are classroom demonstrations that use…
Exploratory Factor Analysis of a Force Concept Inventory Data Set
ERIC Educational Resources Information Center
Scott, Terry F.; Schumayer, Daniel; Gray, Andrew R.
2012-01-01
We perform a factor analysis on a "Force Concept Inventory" (FCI) data set collected from 2109 respondents. We address two questions: the appearance of conceptual coherence in student responses to the FCI and some consequences of this factor analysis on the teaching of Newtonian mechanics. We will highlight the apparent conflation of Newton's…
Stop Faking It! Finally Understanding Science So You Can Teach It. Force and Motion.
ERIC Educational Resources Information Center
Robertson, William C.
This book aims to develop an understanding of basic physics concepts among school teachers in grades 3-8. The concepts covered in this book include force, motion, gravity, and circular motion without intimidating detailed units and formulas. Chapters include: (1) "Newton's First One"; (2) "In Which We Describe Motion and Then Change…
Evaluation of a pneumatic Martian soil sampler concept
NASA Technical Reports Server (NTRS)
Schaefer, John L.; Neathery, James K.; Stencel, John M.
1994-01-01
The pneumatic soil sampler concept was successfully demonstrated by penetrating a Martian simulant soil to a depth of 2 meters. Working gas pressure, composition, and pulsing were evaluated with the objective of minimizing gas usage. Also, the probe penetration force was investigated with the objective of minimizing probe weight. Gas and probe penetration force, while not yet optimized, are within the range which make the soil sampler concept feasible. While the tests described in this report did not answer all the questions and address all the variables associated with pneumatic soil sampling, valuable data experience and knowledge were gained which can be used to further develop the concept.
NASA Astrophysics Data System (ADS)
de Freitas, Elizabeth; Palmer, Anna
2016-12-01
The aim of this article is to investigate how new materialist philosophies of matter can help us study the emergence of scientific thought in young children's activities. We draw extensively on the work of Gilles Deleuze to help us understand scientific concepts as concrete universals. In particular, we show how the concept of force is re-animated through this approach, becoming less deterministic, and more inflected with chance and indeterminism. We show how this approach to concepts moves beyond constructivist socio-cultural theories of learning, and reveals how concepts are `material articulations of the world' intra-acting with all other matter and meaning. Finally, we discuss video data and artifacts from an ongoing ethnographic project in Stockholm entitled `Children's relations to the city'. Our analysis of the classroom video data from this project shows how concepts are not timeless transcendent abstractions, but part of an unfolding event and learning assemblage. Thus the article contributes to research on conceptual change in children, with particular focus on scientific concepts.
ERIC Educational Resources Information Center
Tomaraa, Marina; Tselfes, Vassilis; Goucos, Dimitris
2017-01-01
During the last four decades, the results of a great deal of research have indicated that, prior to any formal instruction in physics, students hold scientifically incorrect ideas about physics concepts in general, and about the force and motion concepts in particular, the latter being considered central in science teaching. To these days,…
ERIC Educational Resources Information Center
Barniol, Pablo; Zavala, Genaro
2014-01-01
In this article we compare students' understanding of vector concepts in problems with no physical context, and with three mechanics contexts: force, velocity, and work. Based on our "Test of Understanding of Vectors," a multiple-choice test presented elsewhere, we designed two isomorphic shorter versions of 12 items each: a test with no…
ERIC Educational Resources Information Center
Yürük, Nejla
2007-01-01
The aim of this paper was to describe the changes in one student's ideas about force and one-dimensional motion concepts and portray the relevant metaconceptual processes that she engaged in during the implementation of metaconceptual teaching interventions. Metaconceptual processes involves metacognitive processes that are directly acting on or…
Social Metaphorical Mapping of the Concept of Force "CHI-KA-RA" in Japanese
ERIC Educational Resources Information Center
Suzuki, Mariko
2005-01-01
This research focused on the concept of "force" ("CHI-KA-RA" in Japanese) in Newtonian mechanics. The primary objective was to develop a tool, based on metaphor, to interpret student thinking in learning scientific topics. The study provides an example of using the tool to trace the process of mutual changes in thinking during a dialog among…
Dividing the Force Concept Inventory into Two Equivalent Half-Length Tests
ERIC Educational Resources Information Center
Han, Jing; Bao, Lei; Chen, Li; Cai, Tianfang; Pi, Yuan; Zhou, Shaona; Tu, Yan; Koenig, Kathleen
2015-01-01
The Force Concept Inventory (FCI) is a 30-question multiple-choice assessment that has been a building block for much of the physics education research done today. In practice, there are often concerns regarding the length of the test and possible test-retest effects. Since many studies in the literature use the mean score of the FCI as the…
Mapping the Future: Optimizing Joint Geospatial Engineering Support
2006-05-16
Environment. Maxwell Air Force Base, AL.: Air University, 1990. Babbage , Ross and Desmond Ball. Geographic Information Systems: Defence Applications...Joint Pub 4-04. Washington, DC: 27 September 2001. Wertz, Charles J. The Data Dictionary, Concepts and Uses. Wellesley, MA: QED Information...Force Defense Mapping for Future Operations, Washington, DC: September 1995, 1-7. 18 Charles J. Wertz, The Data Dictionary, Concepts and Uses
Joint Concept Development and Experimentation: A Force Development Perspective
2012-02-01
REFINED SCENARIO SET KLE S E C U R IT Y E N V IR O N M E N T E X IS T IN G Existing Scenarios KLE Figure 7: Hierarchy of force...CORA TM 2012-036 References ..... [1] Palla, G ., Barabasi, A.L., and Vicsek, T . Quantifying Social Group Evolution. Nature, Vol 446, pp...activités interarmées de développement des forces ( planification axée sur les capacités, élaboration et expérimentation de concepts) ne sont pas bien
NASA Astrophysics Data System (ADS)
Vallett, David Bruce
This study examined the relationships among visuospatial ability, motivation to learn science, and learner conceptions of force across commonly measured demographics with university undergraduates with the aim of examining the support for an evolved sense of force and motion. Demographic variables of interest included age, ethnicity, and gender, which served to determine the ubiquity of the effects of the exogenous variables. Participants (n=91) self selected from introductory physics courses at a large public university in the Mid-Atlantic region of the United States. Utilizing a single-group exploratory design, all participants completed a series of anonymous online instruments to assess the variables of interest. Analysis consisted of an ANOVA for significance testing of demographic variables and a single-level structural equation model (SEM) to ascertain the causal influence of visuospatial ability and affect in the form of motivation on learner conceptions of force. Results of the SEM indicated that while motivation had a nonsignificant (p>.05) impact with this sample, visuospatial ability had a strong (.5 unit change in physics achievement per unit of VSA, p<.05) influence on Newtonian conceptions of mechanics. The results of this study inform physics educators as to the factors underlying conceptual change in Newtonian physics and generate hypotheses regarding the cognitive processes and corresponding neural substrates associated with successful Newtonian reasoning.
A Single-Vector Force Calibration Method Featuring the Modern Design of Experiments
NASA Technical Reports Server (NTRS)
Parker, P. A.; Morton, M.; Draper, N.; Line, W.
2001-01-01
This paper proposes a new concept in force balance calibration. An overview of the state-of-the-art in force balance calibration is provided with emphasis on both the load application system and the experimental design philosophy. Limitations of current systems are detailed in the areas of data quality and productivity. A unique calibration loading system integrated with formal experimental design techniques has been developed and designated as the Single-Vector Balance Calibration System (SVS). This new concept addresses the limitations of current systems. The development of a quadratic and cubic calibration design is presented. Results from experimental testing are compared and contrasted with conventional calibration systems. Analyses of data are provided that demonstrate the feasibility of this concept and provide new insights into balance calibration.
Synoptic forcing of wind relaxations at Pt. Conception, California
NASA Astrophysics Data System (ADS)
Fewings, Melanie R.; Washburn, Libe; Dorman, Clive E.; Gotschalk, Christopher; Lombardo, Kelly
2016-08-01
Over the California Current upwelling system in summer, the prevailing upwelling-favorable winds episodically weaken (relax) or reverse direction for a few days. Near Pt. Conception, California, the wind usually does not reverse, but wind relaxation allows poleward oceanic coastal flow with ecological consequences. To determine the offshore extent and synoptic forcing of these wind relaxations, we formed composite averages of wind stress from the QuikSCAT satellite and atmospheric pressure from the North American Regional Reanalysis (NARR) using 67 wind relaxations during summer 2000-2009. Wind relaxations at Pt. Conception are the third stage of an event sequence that repeatedly affects the west coast of North America in summer. First, 5-7 days before the wind weakens near Pt. Conception, the wind weakens or reverses off Oregon and northern California. Second, the upwelling-favorable wind intensifies along central California. Third, the wind relaxes at Pt. Conception, and the area of weakened winds extends poleward to northern California over 3-5 days. The NARR underestimates the wind stress within ˜200 km of coastal capes by a factor of 2. Wind relaxations at Pt. Conception are caused by offshore extension of the desert heat low. This synoptic forcing is related to event cycles that cause wind reversal as in Halliwell and Allen (1987) and Mass and Bond (1996), but includes weaker events. The wind relaxations extend ˜600 km offshore, similarly to the California-scale hydraulic expansion fan shaping the prevailing winds, and ˜1000 km alongshore, limited by an opposing pressure gradient force at Cape Mendocino.
Analyzing False Positives of Four Questions in the Force Concept Inventory
ERIC Educational Resources Information Center
Yasuda, Jun-ichro; Mae, Naohiro; Hull, Michael M.; Taniguchi, Masa-aki
2018-01-01
In this study, we analyze the systematic error from false positives of the Force Concept Inventory (FCI). We compare the systematic errors of question 6 (Q.6), Q.7, and Q.16, for which clearly erroneous reasoning has been found, with Q.5, for which clearly erroneous reasoning has not been found. We determine whether or not a correct response to a…
NASA Astrophysics Data System (ADS)
Oktarisa, Y.; Utami, I. S.; Denny, Y. R.
2017-02-01
This study has been done to 34 science teacher candidates of Teachers’ Training and Education Faculty of Sultan Ageng Tirtayasa University at their first year of study during 2015-2016 school years. This research focused on student’s misconception about motion and force and how Problem Based Learning (PBL) reducing it. Diagnostic test of misconception about motion and force has been detected by using Force Concept Inventory (FCI). FCI had been used in pretest and posttest, and to find the reducing of students’ misconception N-Gain pretest and posttest of each student had been calculated. Quasi experiment one group pretest and posttest had been used as the research method, and Problem Based Learning (PBL) used as the treatment of manipulation. After two weeks learning motion and force with PBL approach, N-gain which obtained prove that misconception about motion and force had been reducing.
Yang, Chifu; Zhao, Jinsong; Li, Liyi; Agrawal, Sunil K
2018-01-01
Robotic spine brace based on parallel-actuated robotic system is a new device for treatment and sensing of scoliosis, however, the strong dynamic coupling and anisotropy problem of parallel manipulators result in accuracy loss of rehabilitation force control, including big error in direction and value of force. A novel active force control strategy named modal space force control is proposed to solve these problems. Considering the electrical driven system and contact environment, the mathematical model of spatial parallel manipulator is built. The strong dynamic coupling problem in force field is described via experiments as well as the anisotropy problem of work space of parallel manipulators. The effects of dynamic coupling on control design and performances are discussed, and the influences of anisotropy on accuracy are also addressed. With mass/inertia matrix and stiffness matrix of parallel manipulators, a modal matrix can be calculated by using eigenvalue decomposition. Making use of the orthogonality of modal matrix with mass matrix of parallel manipulators, the strong coupled dynamic equations expressed in work space or joint space of parallel manipulator may be transformed into decoupled equations formulated in modal space. According to this property, each force control channel is independent of others in the modal space, thus we proposed modal space force control concept which means the force controller is designed in modal space. A modal space active force control is designed and implemented with only a simple PID controller employed as exampled control method to show the differences, uniqueness, and benefits of modal space force control. Simulation and experimental results show that the proposed modal space force control concept can effectively overcome the effects of the strong dynamic coupling and anisotropy problem in the physical space, and modal space force control is thus a very useful control framework, which is better than the current joint space control and work space control. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Sanchez, J.
2018-06-01
In this paper, the application and analysis of the asymptotic approximation method to a single degree-of-freedom has recently been produced. The original concepts are summarized, and the necessary probabilistic concepts are developed and applied to single degree-of-freedom systems. Then, these concepts are united, and the theoretical and computational models are developed. To determine the viability of the proposed method in a probabilistic context, numerical experiments are conducted, and consist of a frequency analysis, analysis of the effects of measurement noise, and a statistical analysis. In addition, two examples are presented and discussed.
Interaction Forces Between Multiple Bodies in a Magnetic Field
NASA Technical Reports Server (NTRS)
Joffe, Benjamin
1996-01-01
Some of the results from experiments to determine the interaction forces between multiple bodies in a magnetic field are presented in this paper. It is shown how the force values and the force directions depend on the configuration of the bodies, their relative positions to each other, and the vector of the primary magnetic field. A number of efficient new automatic loading and assembly machines, as well as manipulators and robots, have been created based on the relationship between bodies and magnetic fields. A few of these patented magnetic devices are presented. The concepts involved open a new way to design universal grippers for robot and other kinds of mechanisms for the manipulation of objects. Some of these concepts can be used for space applications.
Sensors Technology and Advanced Signal Processing Concepts for Layered Warfare/Layered Sensing
2010-04-01
for challenged environments will require contributions from many diverse technical disciplines across AFRL, the Air Force and beyond. By providing a...APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED. STINFO COPY AIR FORCE...UNITED STATES AIR FORCE AIR FORCE MATERIEL COMMAND NOTICE AND SIGNATURE PAGE Using Government drawings, specifications, or other data
Developing Dependable Software for a System-of-Systems
2005-03-01
the combined casualties of Union and Confederate forces totaled 26,134 soldiers on a single day of battle. [48] The war of attrition concept was a...attrition to a transformational concept of full-spectrum dominance: the ability of US forces, operating unilaterally or in combination with...the complex system-of-systems, these possible combinations are practically limitless. System "unravelings" seem to have an intelligence of their own
ERIC Educational Resources Information Center
Luangrath, Phimpho; Pettersson, Sune; Benckert, Sylvia
2011-01-01
In this study, we investigated why Laotian students had a low score, when they were tested by the Force Concept Inventory (FCI). About 400 first year university students answered the FCI or a Lao version of the FCI (LFCI) with the contexts of some questions changed. The students answered a questionnaire and 34 of the students were interviewed. The…
2006-07-26
FY2008. Although the Navy’s proposed force of 31 amphibious ships includes 10 LPD-17 class ships, the Navy is planning to end LPD-17 procurement in...expresses concerns about the planned reduction in amphibious ships, the sea basing concept, and the MPF(F) program, and requires a report on sea basing...Ship Force Structure Plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Sea Basing Concept of Operations
Students’ understanding of forces: Force diagrams on horizontal and inclined plane
NASA Astrophysics Data System (ADS)
Sirait, J.; Hamdani; Mursyid, S.
2018-03-01
This study aims to analyse students’ difficulties in understanding force diagrams on horizontal surfaces and inclined planes. Physics education students (pre-service physics teachers) of Tanjungpura University, who had completed a Basic Physics course, took a Force concept test which has six questions covering three concepts: an object at rest, an object moving at constant speed, and an object moving at constant acceleration both on a horizontal surface and on an inclined plane. The test is in a multiple-choice format. It examines the ability of students to select appropriate force diagrams depending on the context. The results show that 44% of students have difficulties in solving the test (these students only could solve one or two items out of six items). About 50% of students faced difficulties finding the correct diagram of an object when it has constant speed and acceleration in both contexts. In general, students could only correctly identify 48% of the force diagrams on the test. The most difficult task for the students in terms was identifying the force diagram representing forces exerted on an object on in an inclined plane.
NASA's Gravitational-Wave Mission Concept Study
NASA Technical Reports Server (NTRS)
Stebbins, Robin
2012-01-01
With the conclusion of the NASA/ESA partnership on the Laser interferometer Space Antenna (LISA) Project, NASA initiated a study to explore mission concepts that will accomplish some or all of the LISA science objectives at lower cost. The Gravitational-Wave Mission Concept Study consists of a public Request for Information (RFI), a Core Team of NASA engineers and scientists, a Community Science Team, a Science Task Force, and an open workshop. The RFI yielded 12 mission concepts, 3 instrument concepts and 2 technologies. The responses ranged from concepts that eliminated the drag-free test mass of LISA to concepts that replace the test mass with an atom interferometer. The Core Team reviewed the noise budgets and sensitivity curves, the payload and spacecraft designs and requirements, orbits and trajectories and technical readiness and risk. The Science Task Force assessed the science performance. Three mission concepts have been studied by Team-X, JPL's concurrent design facility, to refine the conceptual design, evaluate key performance parameters, assess risk and estimate cost and schedule. The status of the Study are reported.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bragg-Sitton, Shannon Michelle
The Organization for Economic Cooperation and Development /Nuclear Energy Agency (OECD/NEA) Nuclear Science Committee approved the formation of an Expert Group on Accident Tolerant Fuel (ATF) for LWRs (EGATFL) in 2014. Chaired by Kemal Pasamehmetoglu, INL Associate Laboratory Director for Nuclear Science and Technology, the mandate for the EGATFL defines work under three task forces: (1) Systems Assessment, (2) Cladding and Core Materials, and (3) Fuel Concepts. Scope for the Systems Assessment task force includes definition of evaluation metrics for ATF, technology readiness level definition, definition of illustrative scenarios for ATF evaluation, parametric studies, and selection of system codes. Themore » Cladding and Core Materials and Fuel Concepts task forces will identify gaps and needs for modeling and experimental demonstration; define key properties of interest; identify the data necessary to perform concept evaluation under normal conditions and illustrative scenarios; identify available infrastructure (internationally) to support experimental needs; and make recommendations on priorities. Where possible, considering proprietary and other export restrictions (e.g., International Traffic in Arms Regulations), the Expert Group will facilitate the sharing of data and lessons learned across the international group membership. The Systems Assessment Task Force is chaired by Shannon Bragg-Sitton (INL), while the Cladding Task Force will be chaired by a representative from France (Marie Moatti, Electricite de France [EdF]) and the Fuels Task Force will be chaired by a representative from Japan (Masaki Kurata, Japan Atomic Energy Agency [JAEA]). This report provides an overview of the Systems Assessment Task Force charter and status of work accomplishment.« less
Conceptual coherence of non-Newtonian worldviews in Force Concept Inventory data
NASA Astrophysics Data System (ADS)
Scott, Terry F.; Schumayer, Dániel
2017-06-01
The Force Concept Inventory is one of the most popular and most analyzed multiple-choice concept tests used to investigate students' understanding of Newtonian mechanics. The correct answers poll a set of underlying Newtonian concepts and the coherence of these underlying concepts has been found in the data. However, this inventory was constructed after several years of research into the common preconceptions held by students and using these preconceptions as distractors in the questions. Their sole purpose is to deflect non-Newtonian candidates away from the correct answer. Alternatively, one can argue that the responses could also be treated as polling these preconceptions. In this paper we shift the emphasis of the analysis away from the correlation structure of the correct answers and look at the latent traits underlying the incorrect responses. Our analysis models the data employing exploratory factor analysis, which uses regularities in the data to suggest the existence of underlying structures in the cognitive processing of the students. This analysis allows us to determine whether the data support the claim that there are alternate non-Newtonian worldviews on which students' incorrect responses are based. The existence of such worldviews, and their coherence, could explain the resilience of non-Newtonian preconceptions and would have significant implications to the design of instruction methods. We find that there are indeed coherent alternate conceptions of the world which can be categorized using the results of the research that led to the construction of the Force Concept Inventory.
Alternative Conceptions: Turning Adversity into Advantage
NASA Astrophysics Data System (ADS)
Ferreira, Annalize; Lemmer, Miriam; Gunstone, Richard
2017-08-01
While a vast body of research has identified difficulties in students' understanding about forces and acceleration and their related alternative conceptions, far less research suggests ways to use students' alternative conceptions to enhance conceptual understanding of a specific fundamental concept. This study focused on distinguishing between students' conceptual understanding of the Newtonian concept of gravitational acceleration being the same for all objects and students' alternative conception that heavy objects fall faster. A multiple choice questionnaire was distributed to first year physics students for three consecutive years at a university in South Africa. The results indicate that changing the direction of motion and the physics quantity asked in paired questions revealed practically significant inconsistencies in students' reasoning and conceptions. This research contributes to the body of knowledge in proposing how the alternative conception of mass-related gravitational acceleration can be used in instruction to enhance conceptual understanding of the force-mass-acceleration relationship. Understanding of this relationship not only promotes conceptual understanding of the basic Newtonian concepts of the laws of motion which forms the critical foundation on which more advanced physics courses are built, but also contributes towards students' perception of physics as a set of coherent ideas applicable in all contexts.
Alternating Magnetic Field Forces for Satellite Formation Flying
NASA Technical Reports Server (NTRS)
Youngquist, Robert C.; Nurge, Mark A.; Starr, Stnaley O.
2012-01-01
Selected future space missions, such as large aperture telescopes and multi-component interferometers, will require the precise positioning of a number of isolated satellites, yet many of the suggested approaches for providing satellites positioning forces have serious limitations. In this paper we propose a new approach, capable of providing both position and orientation forces, that resolves or alleviates many of these problems. We show that by using alternating fields and currents that finely-controlled forces can be induced on the satellites, which can be individually selected through frequency allocation. We also show, through analysis and experiment, that near field operation is feasible and can provide sufficient force and the necessary degrees of freedom to accurately position and orient small satellites relative to one another. In particular, the case of a telescope with a large number of free mirrors is developed to provide an example of the concept. We. also discuss the far field extension of this concept.
2011-12-01
Contra Affair (1988) USS Iowa (BB-61) turret explosion, investigation (1989) US Naval Academy sexual harassment scandal (1989) Female midshipman...down (1981); Grenada intervention (1983), Lebanon intervention (1982-3); Med hijacker force-down (1985); US assistance to Central American anti...LTG Colin Powell USA Reaction to disastrous USMC intervention in Lebanon (1983) Forces for Unified Commands memorandum (Feb 1987) JCS Pub 26
DOE Office of Scientific and Technical Information (OSTI.GOV)
Salmi, M.D.
In 1984, the Chiefs of Staff of the US Army and the US Air Force signed a Memorandum of Understanding (MOU) outlining a concept for the joint air defense of overseas air bases. With little previous experience in joint rear-area operations, problems were bound to occur, especially in the area of chemical warfare defense (CWD). The Army bases its CWD doctrine on the concept of maneuver while the Air Force bases its doctrine on being tied to air bases with little or no capability to avoid chemical attacks. Each Service developed its doctrine to support its operational concept. This studymore » compared and contrasted the CWD doctrine of the Army and the Air Force. If found a great deal of commonality exists; however, there are also several problems which could lead to death, injury, and degradation of sortie generation capability.« less
NASA Technical Reports Server (NTRS)
Smith, G. A.; Meyer, G.
1980-01-01
The results of a simulation study of an alternative design concept for an automatic landing control system are presented. The alternative design concept for an automatic landing control system is described. The design concept is the total aircraft flight control system (TAFCOS). TAFCOS is an open loop, feed forward system that commands the proper instantaneous thrust, angle of attack, and roll angle to achieve the forces required to follow the desired trajector. These dynamic trim conditions are determined by an inversion of the aircraft nonlinear force characteristics. The concept was applied to an A-7E aircraft approaching an aircraft carrier. The implementation details with an airborne digital computer are discussed. The automatic carrier landing situation is described. The simulation results are presented for a carrier approach with atmospheric disturbances, an approach with no disturbances, and for tailwind and headwind gusts.
2013-06-13
allowing rapid response to unforeseen crises. This includes sending forces to assist in the disaster relief operations after the October 2005 earthquake...a need for other capabilities. PACOM was able to provide disaster relief support to Japan immediately after their epic triple disaster in eastern...
Back to the Future: Does History Support the Expeditionary Air Force Concept?
2000-04-01
Operations Forces 550, “Agile Combat Support,” Mr. Ron Orr, USAF/IL, 2 Feb 00. 4 Davis, pg. 11. 5 Toulmin , H.A., Jr., Air Service, American...John A., “The Expeditionary Air Force Takes Shape,” Air Force Magazine, Vol. 80, No. 6, June 1997. Toulmin , H.A., Jr., Air Service, American
NASA Astrophysics Data System (ADS)
Fulmer, Gavin W.; Liang, Ling L.; Liu, Xiufeng
2014-11-01
This exploratory study applied a proposed force and motion learning progression (LP) to high-school and university students and to content involving both one- and two-dimensional force and motion situations. The Force Concept Inventory (FCI) was adapted, based on a previous content analysis and coding of the questions in the FCI in terms of the level descriptors of the LP. Using a Rasch measurement model and latent class analysis, students' responses were tested for fit with the proposed LP. Results indicated that the recoded FCI response options are generally consistent with a progression of difficulties as proposed in the LP, and that the students could be organized into different groups with progressively different levels of ability. However, reliability for the ability estimates was only moderate and response options at lower levels of the LP were not well differentiated. Implications for the assessments with LPs and revisions for both the FCI and the force and motion LP are also discussed.
NASA Technical Reports Server (NTRS)
Razzaq, Zia; Mykins, David W.
1987-01-01
Potential passive damping concepts for use in space structures are identified. The effectiveness of copper brush, wool swab, and silly putty in chamber dampers is investigated through natural vibration tests on a tubular aluminum member. The member ends have zero translation and possess partial rotational restraints. The silly putty in chamber dampers provide the maximum passive damping efficiency. Forced vibration tests are then conducted with one, two, and three damper chambers containing silly putty. Owing to the limitation of the vibrator used, the performance of these dampers could not be evaluated experimentally until the forcing function was disengaged. Nevertheless, their performance is evaluated through a forced dynamic finite element analysis conducted as a part of this investigation. The theoretical results based on experimentally obtained damping ratios indicate that the passive dampers are considerably more effective under member natural vibration than during forced vibration. Also, the maximum damping under forced vibration occurs at or near resonance.
Design concepts and cost studies for magnetic suspension and balance systems. [wind tunnel apparatus
NASA Technical Reports Server (NTRS)
Bloom, H. L.
1982-01-01
The application of superconducting magnets for suspension and balance of wind tunnel models was studied. Conceptual designs are presented for magnetic suspension and balance system (MSBS) configurations compatible with three high Reynolds number cases representing specified combinations of test conditions and model sizes. Concepts in general met initially specified performance requirements such as duty cycle, force and moment levels, model angular displacement and positioning accuracy with nominal design requirements for support subsystems. Other performance requirements, such as forced model sinusoidal oscillations, and control force magnitude and frequency, were modified so as to alleviate the magnitude of magnet, power, and cryogenic design requirements.
Skeletal muscle is a biological example of a linear electroactive actuator
NASA Astrophysics Data System (ADS)
Lieber, Richard L.
1999-05-01
Skeletal muscle represents a classic biological example of a structure-function relationship. This paper reviews basic muscle anatomy and demonstrates how molecular motion on the order of nm distances is converted into the macroscopic movements that are possible with skeletal muscle. Muscle anatomy provides a structural basis for understanding the basic mechanical properties of skeletal muscle -- namely, the length-tension relationship and the force-velocity relationships. The length-tension relationship illustrates that muscle force generation is extremely length dependent due to the interdigitation of the contractile filaments. The force-velocity relationship is characterized by a rapid force drop in muscle with increasing shortening velocity and a rapid rise in force when muscles are forced to lengthen. Finally, muscle architecture -- the number and arrangement of muscle fibers -- has a profound effect on the magnitude of muscle force generated and the magnitude of muscle excursion. These concepts demonstrate the elegant manner in which muscle acts as a biologically regenerating linear motor. These concepts can be used in developing artificial muscles as well as in performing surgical reconstructive procedures with various donor muscles.
Foot force production and asymmetries in elite rowers.
Buckeridge, Erica M; Bull, Anthony M J; McGregor, Alison H
2014-03-01
The rowing stroke is a leg-driven action, in which forces developed by the lower limbs provide a large proportion of power delivered to the oars. In terms of both performance and injury, it is important to initiate each stroke with powerful and symmetrical loading of the foot stretchers. The aims of this study were to assess the reliability of foot force measured by footplates developed for the Concept2 indoor ergometer and to examine the magnitude and symmetry of bilateral foot forces in different groups of rowers. Five heavyweight female scullers, six heavyweight female sweep rowers, and six lightweight male (LWM) rowers performed an incremental step test on the Concept2 ergometer. Vertical, horizontal, and resultant forces were recorded bilaterally, and asymmetries were quantified using the absolute symmetry index. Foot force was measured with high consistency (coefficient of multiple determination > 0.976 +/- 0.010). Relative resultant, vertical, and horizontal forces were largest in LWM rowers, whilst average foot forces significantly increased across stroke rates for all three groups of rowers. Asymmetries ranged from 5.3% for average resultant force to 28.9% for timing of peak vertical force. Asymmetries were not sensitive to stroke rate or rowing group, however, large inter-subject variability in asymmetries was evident.
Focusing on Concepts by Covering Them Simultaneously
ERIC Educational Resources Information Center
Shwartz, Pete
2017-01-01
"Parallel" pedagogy covers the four mechanics concepts of momentum, energy, forces, and kinematics simultaneously instead of building each concept on an understanding of the previous one. Course content is delivered through interactive videos, allowing class time for group work and student-centered activities. We start with simple…
Passive damping concepts for free and forced member and grillage vibration
NASA Technical Reports Server (NTRS)
Razzaq, Zia; Najjar, Bassam
1988-01-01
The performance of potential passive damping concepts is investigted for a long tubular aluminum alloy member, and a two-bar grillage structure. The members are restrained partially at the ends and are of the type being considered by NASA for possible use in the construction of a future space station. Four different passive damping concepts are studied and include nylon brush, wool swab, copper brush, and silly putty in chamber dampers. Both free and forced vibration tests are conducted. It is found that the silly putty in chamber damper concept provides considerably greater passive damping as compared to that of the other three concepts. For the grillage natural vibration, a five wool swab damper configuration provides greater damping than the five silly putty dampers in chamber configuration. Due to the constrained motion imposed by the vibrator used in the tests, the effectiveness of the passive dampers could not be adequately evaluated for the individual member. However, it is found that for the grillage under forced vibration, the five silly putty dampers in chamber damper configuration provides very effective passive damping although only at and around the resonant frequency. At resonance, these dampers provide a 51 percent reduction in the dynamic magnification factor for this case.
What does it mean to be an oncology nurse? Reexamining the life cycle concepts.
Cohen, Marlene Z; Ferrell, Betty R; Vrabel, Mark; Visovsky, Constance; Schaefer, Brandi
2010-09-01
To summarize the current research pertaining to the concepts initially examined by the Oncology Nursing Society Life Cycle of the Oncology Nurse Task Force and related projects completed in 1994. Published articles on the 21 concepts from the Oncology Nursing Society Life Cycle of the Oncology Nurse Task Force work. Research published in English from 1995-2009 was obtained from PubMed, CINAHL(R), PsycINFO, ISI Science, and EBSCO Health Source(R): Nursing/Academic Edition databases. Most of the concepts identified from the Oncology Nursing Society Life Cycle of the Oncology Nurse Task Force have been examined in the literature. Relationships and witnessing suffering were common concepts among studies of the meaning of oncology nursing. Nurses provide holistic care, and not surprisingly, holistic interventions have been found useful to support nurses. Interventions included storytelling, clinical support of nurses, workshops to find balance in lives, and dream work. Additional support comes from mentoring. The research identified was primarily descriptive, with very few interventions reported. Findings have been consistent over time in diverse countries. This review indicates that although the healthcare system has changed significantly in 15 years, nurses' experiences of providing care to patients with cancer have remained consistent. The need for interventions to support nurses remains.
2009-04-03
the concept calls for interagency task forces ( IATF ) co-led by a Special Representative of the President and the Commander of a military Joint Task...functional lines, civilian and military members comprise the IATF staff. Furthermore, when possible, the concept establishes the IATF early outside the...prepare and plan for the complex contingency. When deployed, the IATF relies on the military joint task force for most of its support including
Factors Affecting the Role and Employment of Peacekeeping Forces in Africa South of the Sahara.
1982-12-01
reinforcing. Although abstract, the w concept is similar to that used by Emile Durkheim in his discussion of social solidarity. I rhe concept of...I Forces Involved: Support for Congolese air power: Ethiopia provided Emil a jet fighter and possibly pilots; Ghana, seven pilots and two air traffic...problems Durkheim 3 ’ encountered when he attempted to measure social solidarity. His earlier efforts to social solidarity directly through an
A Survey of Laser Lightning Rod Techniques
1991-08-21
impossibility of the LLR concept. 4 REFERENCES 1. Hagen, 1969: "Diffraction-limited high irradiance Nd- glass laser system, J. Appl. Phys., 40, 511-516. 2. Greig...study", Air Force Flight Dynamics Laboratory,, Technical Report AFFDL-TR-78-60. AD A063 847. 8. Schubert, C.N., Jr. and J.R. Lippert , 1979...pp. 132-135. 9. Lippert , J.R.,1978: "Laser-Induced Lightning Concept Exper- iment", Air Force Flight Dynamics Laboratory, Technical Report AFFDL-TR
ERIC Educational Resources Information Center
Savinainen, Antti; Makynen, Asko; Nieminen, Pasi; Viiri, Jouni
2013-01-01
Earlier research has shown that after physics instruction, many students have difficulties with the force concept, and with constructing free-body diagrams (FBDs). It has been suggested that treating forces as interactions could help students to identify forces as well as to construct the correct FBDs. While there is evidence that identifying…
First Multinational AirMedEvac Crew Concept in NATO
2010-04-01
Lufttransportgeschwader 61 Kauferinger Str. 130 D-86929 Penzing GERMANY ChristianStrobl@Bundeswehr.org EXPERIENCES WITH THE GERMAN-DUTCH COOPERATION IN...Doctor Medical Forces 1 1 Anaesthesiological Assistant / Medic Sergeant Medical Forces 2 1 1 Medical Crew Chief / Medic Sergeant, Flight Nurse...Paramedic Medical Forces 1 1 Paramedic / Medic Sergeant (thereof with experience in intensive care) Medical Forces 6 (4) 2 Aidman / Medic
Code of Federal Regulations, 2010 CFR
2010-07-01
... 32 National Defense 6 2010-07-01 2010-07-01 false Concept. 989.2 Section 989.2 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE ENVIRONMENTAL PROTECTION ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.2 Concept. (a) This part provides a framework on how to comply with NEPA and...
Some Basic Concepts of Wave-Particle Interactions in Collisionless Plasmas
NASA Technical Reports Server (NTRS)
Lakhina, Gurbax S.; Tsurutani, Bruce T.
1997-01-01
The physical concepts of wave-particle interactions in a collisionless plasma are developed from first principles. Using the Lorentz force, starting with the concepts of gyromotion, particle mirroring and the loss-cone, normal and anomalous cyclotron resonant interactions, pitch-angle scattering, and cross-field diffusion are developed.
Assessing Conceptual Knowledge for the Physics of Semiconductors
ERIC Educational Resources Information Center
Ene, Emanuela
2013-01-01
Following the trend in science and engineering education generated by the visible impact created by the Force Concept Inventory (FCI), the investigator developed a Physics of Semiconductors Concept Inventory (PSCI). PSCI fills the need of standardized concept tests for undergraduate education in photonics and electrical engineering. The structure…
Physics that Textbook Writers Usually Get Wrong: III.
ERIC Educational Resources Information Center
Bauman, Robert P.
1992-01-01
Examines inconsistencies in science textbook discussions of vector quantities and force. Provides illustrations of textbook inconsistencies related to Newton's laws of motion and the concepts of centrifugal and coriolis force. (MDH)
Infrastructure Task Force Sustainable Infrastructure Goals and Concepts Document
This document outlines the concepts of appropriate infrastructure and sustainable management entities to guide the coordinated federal efforts to achieve greater sustainable access to safe drinking water and basic sanitation.
Systems evaluation of thermal bus concepts
NASA Technical Reports Server (NTRS)
Stalmach, D. D.
1982-01-01
Thermal bus concepts, to provide a centralized thermal utility for large, multihundred kilowatt space platforms, were studied and the results are summarized. Concepts were generated, defined, and screened for inclusion in system level thermal bus trades. Parametric trade studies were conducted in order to define the operational envelope, performance, and physical characteristics of each. Two concepts were selected as offering the most promise for thermal bus development. All of four concepts involved two phase flow in order to meet the required isothermal nature of the thermal bus. Two of the concepts employ a mechanical means to circulate the working fluid, a liquid pump in one case and a vapor compressor in another. Another concept utilizes direct osmosis as the driving force of the thermal bus. The fourth concept was a high capacity monogroove heat pipe. After preliminary sizing and screening, three of these concepts were selected to carry into the trade studies. The monogroove heat pipe concept was deemed unsuitable for further consideration because of its heat transport limitations. One additional concept utilizing capillary forces to drive the working fluid was added. Parametric system level trade studies were performed. Sizing and weight calculations were performed for thermal bus sizes ranging from 5 to 350 kW and operating temperatures in the range of 4 to 120 C. System level considerations such as heat rejection and electrical power penalties and interface temperature losses were included in the weight calculations.
Air Force Civil Engineering Center Fiscal Year 1978 Air Force Technical Objectives Document.
1976-12-15
for the theater airbase, pavement studies, environmental pollution abatement and control, air mobility concepts, energy conservation, fire fighting equipment, air base support, and warm fog dispersal. (Author)
Recent Advances in Our Understanding of Nuclear Forces
NASA Astrophysics Data System (ADS)
Machleidt, Ruprecht
2007-05-01
The attempts to find the right (underlying) theory for the nuclear force have a long and stimulating history. Already in 1953, Hans Bethe stated that ``more man-hours have been given to this problem than to any other scientific question in the history of mankind.'' In search for the nature of the nuclear force, the idea of sub-nuclear particles was created which, eventually, generated the field of particle physics. I will review this productive history of hope, error, and desperation. Finally, I will discuss recent ideas which apply the concept of an effective field theory to low-energy QCD. There are indications that this concept may provide the right framework to properly understand the nuclear force. To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2007.NWS07.B2.1
Network Design Guidance for the Global Special Operations Forces Network
2014-12-01
41 a. Concepts Emerge.....................................................................42 b. Model...78 a. Culture .....................................................................................78 b... Concept for Joint Operations COIN counterinsurgency COM commercial DMA Deputy Municipal Administrator DOD Department of Defense DOS Department
Passive damping concepts for tubular beams with partial rotational and translational end restraints
NASA Technical Reports Server (NTRS)
Razzaq, Zia; Muyundo, David K.
1991-01-01
The main objectives of the study are: (1) identification of potential passive damping concepts for slender tubular structural members with rotational and translational end springs under natural and forced-free vibrations; (2) evaluation of damping efficiencies of the various damping concepts; and (3) evaluation of the suitability of a theoretical finite difference analysis by comparison to the experimental results for the case of natural vibrations. Only member flexural an translation motion is considered. The natural vibration study is conducted on the seven damping concepts and for only one specific initial deflection. The most suitable of the seven dampers is further investigated under forced-free vibrations. In addition only one set of end springs is used for all of the experiments. The results show that passive damping provides a possible approach to structural vibration reduction.
Evaluating learning and teaching using the Force Concept Inventory
NASA Astrophysics Data System (ADS)
Zitzewitz, Paul
1997-04-01
Teaching methods used in the calculus-based mechanics course for engineers and scientists (P150) at the University of Michigan-Dearborn were markedly changed in September, 1996. Lectures emphasize active learning with Mazur's ConcepTests, Sokoloff's Interactive Demonstrations, and Van Heuvelen's ALPS Kit worksheets. Students solve context-rich problems using Van Heuvelen's multiple representation format in cooperative groups in discussion sections. Labs were changed to use MBL emphasizing concepts and Experiment Problems to learn lab-based problem solving. Pre- and post-testing of 400 students with the Force Concept Inventory has demonstrated considerable success. The average increase in score has been 35-45methods as defined by Hake. The methods and results will be discussed. Detailed analyses of the FCI results will look at success in teaching specific concepts and the effect of student preparation in mathematics and high school physics.
Revolutionary Concepts for Helicopter Noise Reduction: SILENT Program
NASA Technical Reports Server (NTRS)
Edwards, Bryan; Cox, Charles; Booth, Earl R., Jr. (Technical Monitor)
2002-01-01
As part of a NASA initiative to reduce helicopter main rotor noise, a Phase 1 study has been performed of candidate noise reduction concepts. Both conventional and novel design technologies have been analyzed that reduce the community impact of helicopter operations. In this study the noise reduction potential and design implications are assessed for conventional means of noise reduction, e.g., tip speed reduction, tip shapes and airfoil tailoring, and for two innovative design concepts: modulated blade spacing and x-force control. Main rotor designs that incorporate modulated blade spacing are shown to have reduced peak noise levels in most flight operations. X-force control alters the helicopter's force balance whereby the miss distance between main rotor blades and shed vortices can be controlled. This control provides a high potential to mitigate BVI noise radiation. Each concept is evaluated using best practice design and analysis methods, achieving the study's aim to significantly reduce noise with minimal performance degradation and no vibration increase. It is concluded that a SILENT main rotor design, incorporating the modulated blade spacing concept, offers significantly reduced noise levels and the potential of a breakthrough in how a helicopter's sound is perceived and judged. The SILENT rotor represents a definite advancement in the state-of-the-art and is selected as the design concept for demonstration in Phase 2. A Phase 2 Implementation Plan is developed for whirl cage and wind tunnel evaluations of a scaled model SILENT rotor.
Two blowing concepts for roll and lateral control of aircraft
NASA Technical Reports Server (NTRS)
Tavella, D. A.; Wood, N. J.; Lee, C. S.; Roberts, L.
1986-01-01
Two schemes to modulate aerodynamic forces for roll and lateral control of aircraft have been investigated. The first scheme, called the lateral blowing concept, consists of thin jets of air exiting spanwise, or at small angle with the spanwise direction, from slots at the tips of straight wings. For this scheme, in addition to experimental measurements, a theory was developed showing the analytical relationship between aerodynamic forces and jet and wing parameters. Experimental results confirmed the theoretically derived scaling laws. The second scheme, which was studied experimentally, is called the jet spoiler concept and consists of thin jets exiting normally to the wing surface from slots aligned with the spanwise direction.
New Close Air Support Doctrine: Getting Control of Emerging Technology and Advanced Concepts
2002-05-31
tactics, techniques, and procedures (TTPs). Since 1996 , the JCAS community, lead by an Office of the Secretary of Defense JCAS Joint Test Force, has tried...addressing CAS control in the urban environment. The first of these is Major Kenneth T. Stefanek’s thesis “The Utilization of Inertially Guided Weapons in...the 1995 to 1996 academic year to be submitted to the Chief of Staff of the Air Force in support of future concepts development. This paper, “Close Air
2015-04-01
capability to conduct airfield surveys outside of a permissive environment. Optimizing the Rapid Raptor Forward Arming and Refueling Point (FARP...9] An Initial Approach at Dispersing Air Operations: Rapid Raptor Concept ................... [12] Rapid Raptor : Optimized...Approach at Dispersing Air Operations: Rapid Raptor Concept The Air Force Rapid Raptor Fighter Forward Arming and Refueling (FARP) concept is an
The role of impact forces and foot pronation: a new paradigm.
Nigg, B M
2001-01-01
This article discusses the possible association between impact forces and foot pronation and the development of running-related injuries, and proposes a new paradigm for impact forces and foot pronation. The article is based on a critical analysis of the literature on heel-toe running addressing kinematics, kinetics, resultant joint movements and forces, muscle activity, subject and material characteristics, epidemiology, and biologic reactions. However, this paper is not a review of the literature but rather an attempt to replace the established concepts of impact forces and movement control with a new paradigm that would allow explaining some of the current contradictions in this topic of research. The analysis included all papers published on this topic over the last 25 years. For the last few years, it concentrated on papers expressing critical concerns on the established concepts of impact and movement control. An attempt was made to find indications in the various publications to support or reject the current concept of impact forces and movement control. Furthermore, the results of the available studies were searched for indications expanding the current understanding of impact forces and movement control in running. Data were synthesized revealing contradictions in the experimental results and the established concepts. Based on the contradictions in the existing research publications, a new paradigm was proposed. Theoretical, experimental, and epidemiological evidence on impact forces showed that one cannot conclude that impact forces are important factors in the development of chronic and/or acute running-related injuries. A new paradigm for impact forces during running proposes that impact forces are input signals that produce muscle tuning shortly before the next contact with the ground to minimize soft tissue vibration and/or reduce joint and tendon loading. Muscle tuning might affect fatigue, comfort, work, and performance. Experimental evidence suggests that the concept of "aligning the skeleton" with shoes, inserts, and orthotics should be reconsidered. They produce only small, not systematic. and subject-specific changes of foot and leg movement. A new paradigm for movement control for the lower extremities proposes that forces acting on the foot during the stance phase act as an input signal producing a muscle reaction. The cost function used in this adaptation process is to maintain a preferred joint movement path for a given movement task. If an intervention counteracts the preferred movement path, muscle activity must be increased. An optimal shoe, insert, or orthotic reduces muscle activity. Thus, shoes, inserts, and orthotics affect general muscle activity and, therefore, fatigue, comfort, work, and performance. The two proposed paradigms suggest that the locomotor system use a similar strategy for "impact" and "movement control." In both cases the locomotor system keeps the general kinematic and kinetic situations similar for a given task. The proposed muscle tuning reaction to impact loading affects the muscle activation before ground contact. The proposed muscle adaptation to provide a constant joint movement pattern affects the muscle activation during ground contact. However, further experimental and theoretical studies are needed to support or reject the proposed paradigms.
Using a Force Concept Inventory Test with Visually Impaired and Blind Students
ERIC Educational Resources Information Center
Bulbul, Mustafa Sahin; Garip, Belkis; Özdemir, Ömer Faruk
2015-01-01
This paper reports on a study to determine whether blind students' conceptualizations of force and motion differ from sighted students. This is particularly concerned with the question of whether the students' visual experiences have any relation to their conceptualizations or misconceptualization about force and motion. The research was designed…
Inertial Force Coupling to Nonlinear Aeroelasticity of Flexible Wing Aircraft
NASA Technical Reports Server (NTRS)
Nguyen, Nhan T.; Ting, Eric
2016-01-01
This paper investigates the inertial force effect on nonlinear aeroelasticity of flexible wing aircraft. The geometric are nonlinearity due to rotational and tension stiffening. The effect of large bending deflection will also be investigated. Flutter analysis will be conducted for a truss-braced wing aircraft concept with tension stiffening and inertial force coupling.
Can the self-propulsion of anisotropic microswimmers be described by using forces and torques?
NASA Astrophysics Data System (ADS)
ten Hagen, Borge; Wittkowski, Raphael; Takagi, Daisuke; Kümmel, Felix; Bechinger, Clemens; Löwen, Hartmut
2015-05-01
The self-propulsion of artificial and biological microswimmers (or active colloidal particles) has often been modelled by using a force and a torque entering into the overdamped equations for the Brownian motion of passive particles. This seemingly contradicts the fact that a swimmer is force-free and torque-free, i.e. that the net force and torque on the particle vanish. Using different models for mechanical and diffusiophoretic self-propulsion, we demonstrate here that the equations of motion of microswimmers can be mapped onto those of passive particles with the shape-dependent grand resistance matrix and formally external effective forces and torques. This is consistent with experimental findings on the circular motion of artificial asymmetric microswimmers driven by self-diffusiophoresis. The concept of effective self-propulsion forces and torques significantly facilitates the understanding of the swimming paths, e.g. for a microswimmer under gravity. However, this concept has its limitations when the self-propulsion mechanism of a swimmer is disturbed either by another particle in its close vicinity or by interactions with obstacles, such as a wall.
Unified Technical Concepts. Application Modules Volume I.
ERIC Educational Resources Information Center
Center for Occupational Research and Development, Inc., Waco, TX.
Unified Technical Concepts (UTC) is a modular system for teaching applied physics in two-year postsecondary technician programs. This UTC laboratory textbook, the first of two volumes, consists of 56 learning modules dealing with basic concepts of physics. Addressed in the individual chapters of the guide are the following topics: force, work,…
Learning and New Sociability: Schooling and the Concept of the Child in the Spanish Enlightenment
ERIC Educational Resources Information Center
Caruso, Marcelo
2012-01-01
The article presents evidence of a shift in the conception of childhood towards communication, social intercourse and interaction as central forces in shaping children's identities in Spain during the last decades of the eighteenth century. Following a significant shift of meaning regarding the concept of children's "inclinations", the…
Improving Minuteman III Maintenance Concepts
2017-03-23
INSTITUTE OF TECHNOLOGY Wright-Patterson Air Force Base, Ohio DISTRIBUTION STATEMENT A. APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED...Department of Operational Sciences Graduate School of Engineering and Management Air Force Institute of Technology Air University Air Education and
The Total Force: Cultural Considerations for the Future of the Total Force Integration
2017-03-31
force. In order to achieve a new TFI culture the Air Force must make a plan, and provide the education , tools, and road map; to cultivate a new set of...Force leadership; and taught holistically at all levels, ranks; and in every professional military education institution. 3 Part I...complex than transferring assets and improving individual units. Cohen’s principles spoke to a need for a cultural transformation . Today’s TFI concept
Validating two questions in the Force Concept Inventory with subquestions
NASA Astrophysics Data System (ADS)
Yasuda, Jun-ichiro; Taniguchi, Masa-aki
2013-06-01
In this study, we evaluate the structural validity of Q.16 and Q.7 in the Force Concept Inventory (FCI). We address whether respondents who answer Q.16 and Q.7 correctly actually have an understanding of the concepts of physics tested in the questions. To examine respondents’ levels of understanding, we use subquestions that test them on concepts believed to be required to answer the actual FCI questions. Our sample size comprises 111 respondents; we derive false-positive ratios for prelearners and postlearners and then statistically test the difference between them. We find a difference at the 0.05 significance level for both Q.16 and Q.7, implying that it is possible for postlearners to answer both questions without an understanding of the concepts of physics tested in the questions; therefore, the structures of Q.16 and Q.7 are invalid. In this study, we only evaluate the validity of these two FCI questions; we do not assess the validity of previous studies that have compared total FCI scores.
Hydrogen disposal investigation for the Space Shuttle launch complex at Vandenberg Air Force Base
NASA Technical Reports Server (NTRS)
Breit, Terry J.; Elliott, George
1987-01-01
The concern of an overpressure condition on the aft end of the Space Shuttle caused by ignition of unburned hydrogen being trapped in the Space Shuttle Main Engine exhaust duct at the Vandenberg AFB launch complex has been investigated for fifteen months. Approximately twenty-five concepts have been reviewed, with four concepts being thoroughly investigated. The four concepts investigated were hydrogen burnoff ignitors (ignitors located throughout the exhaust duct to continuously ignite any unburned hydrogen), jet mixing (utilizing large volumes of high pressure air to ensure complete combustion of the hydrogen), steam inert (utilizing flashing hot water to inert the duct with steam) and open duct concept (design an open duct or above grade J-deflector to avoid trapping hydrogen gas). Extensive studies, analyses and testing were performed at six test sites with technical support from twenty-two major organizations. In December 1986, the Air Force selected the steam inert concept to be utilized at the Vandenberg launch complex and authorized the design effort.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bragg-Sitton, Shannon Michelle
The Organization for Economic Cooperation and Development /Nuclear Energy Agency (OECD/NEA) Nuclear Science Committee approved the formation of an Expert Group on Accident Tolerant Fuel (ATF) for LWRs (EGATFL) in 2014. Chaired by Kemal Pasamehmetoglu, INL Associate Laboratory Director for Nuclear Science and Technology, the mandate for the EGATFL defines work under three task forces: (1) Systems Assessment, (2) Cladding and Core Materials, and (3) Fuel Concepts. Scope for the Systems Assessment task force (TF1) includes definition of evaluation metrics for ATF, technology readiness level definition, definition of illustrative scenarios for ATF evaluation, and identification of fuel performance and systemmore » codes applicable to ATF evaluation. The Cladding and Core Materials (TF2) and Fuel Concepts (TF3) task forces will identify gaps and needs for modeling and experimental demonstration; define key properties of interest; identify the data necessary to perform concept evaluation under normal conditions and illustrative scenarios; identify available infrastructure (internationally) to support experimental needs; and make recommendations on priorities. Where possible, considering proprietary and other export restrictions (e.g., International Traffic in Arms Regulations), the Expert Group will facilitate the sharing of data and lessons learned across the international group membership. The Systems Assessment task force is chaired by Shannon Bragg-Sitton (Idaho National Laboratory [INL], U.S.), the Cladding Task Force is chaired by Marie Moatti (Electricite de France [EdF], France), and the Fuels Task Force is chaired by a Masaki Kurata (Japan Atomic Energy Agency [JAEA], Japan). The original Expert Group mandate was established for June 2014 to June 2016. In April 2016 the Expert Group voted to extend the mandate one additional year to June 2017 in order to complete the task force deliverables; this request was subsequently approved by the Nuclear Science Committee. This report provides an update on the status Systems Assessment Task Force activities.« less
Future's operation areas: new-generation suppression enemy air defence (SEAD) elements
NASA Astrophysics Data System (ADS)
Hazinedar, Ä.°lker
2015-05-01
Since air vehicles took place in the theater of operations, they have become the indispensable elements and the strongest attack power of armed forces. In the following period, with technological development, supersonic aircrafts took place in the operation area and this increased effectiveness of air vehicles much more. Air forces have used these aircrafts during important missions like strategic attack and air defense operations. On the other hand, decision makers understood that it was not feasible to intercept fighter aircrafts by executing combat air patrol flight missions. Since there is not enough reaction time to intercept the high speed aircrafts, ground stationed Surface to Air Missiles (SAM) system requirement has emerged. Therefore, SAM systems took place in the operation scene as well. Due to the fact that SAM systems emerged against the attack power, the attack aircrafts are to keep away from the fire of the ground stationed SAM systems. Hence, the requirement of Suppression Enemy Air Defense (SEAD) arose. SEAD elements take under suppression the radar of the SAM systems. In this way, attack aircrafts are able to attack without the risk of SAM systems. The purpose of this study is to find new methods or concepts in order to protect friendly attack aircrafts against ground based surface to air missiles' fires. Modernization of SAM systems and new generation SAM system producing activities have proceeded with positive acceleration. So, current SEAD elements and concepts are not able to cover the requirements due to the increased SAM system ranges. According to the concepts, SEAD weapons` ranges must be longer than the SAM weapons' ranges to protect friendly aircrafts. In this study, new concept was offered to overcome the deficiencies of current SEAD concept. The elements of new concepts were put forward. Classic SEAD concept and new generation concepts were assessed by using SWOT analysis technique. As a result, this study has revealed that, air forces' effectiveness can be enhanced by using new generation SEAD concepts against enemy SAM systems.
F-18 HARV research pilot Dana Purifoy
NASA Technical Reports Server (NTRS)
1996-01-01
Dana D. Purifoy is an aerospace research pilot at NASA's Dryden Flight Research Center, Edwards, California. He joined NASA in August 1994. Purifoy is a former Air Force test pilot who served as a project pilot in the joint NASA/Air Force X-29 Forward Swept Wing research program conducted at Dryden from 1984 to 1991. His most recent assignment in the Air Force was flying U-2 aircraft as a test pilot at Air Force Plant 42, Palmdale, CA. In addition to flying the X-29 at Dryden as an Air Force pilot, Purifoy also served as project pilot and joint test force director with the AFTI F-16 (Advanced Fighter Technology Integration/F-16) program, also located at Dryden. Before his assignments as project pilot on the X-29 and AFTI/F-16 aircraft, Purifoy was chief of the Academics Systems Branch at the Air Force Test Pilot School at Edwards. Prior to becoming a test pilot, he flew F-111 and F-16 aircraft in Great Britain and Germany. He has accumulated 3800 hours of flying time in his career. The final flight for the F-18 High Alpha Research Vehicle (HARV) took place at NASA Dryden on May 29, 1996. The highly modified F-18 airplane flew 383 flights over a nine year period and demonstrated concepts that greatly increase fighter maneuverability. Among concepts proven in the aircraft is the use of paddles to direct jet engine exhaust in cases of extreme altitudes where conventional control surfaces lose effectiveness. Another concept, developed by NASA Langley Research Center, is a deployable wing-like surface installed on the nose of the aircraft for increased right and left (yaw) control on nose-high flight angles.
NASA Astrophysics Data System (ADS)
Shoop, Brian; Johnston, Michael; Goehring, Richard; Moneyhun, Jon; Skibba, Brian
2006-05-01
MDARS is a Semi-autonomous unmanned ground vehicle with intrusion detection & assessment, product & barrier assessment payloads. Its functions include surveillance, security, early warning, incident first response and product and barrier status primarily focused on a depot/munitions security mission at structured/semi-structured facilities. MDARS is in Systems Development and Demonstration (SDD) under the Product Manager for Force Protection Systems (PM-FPS). MDARS capabilities include semi-autonomous navigation, obstacle avoidance, motion detection, day and night imagers, radio frequency tag inventory/barrier assessment and audio challenge and response. Four SDD MDARS Patrol Vehicles have been undergoing operational evaluation at Hawthorne Army Depot, NV (HWAD) since October 2004. Hawthorne personnel were trained to administer, operate and maintain the system in accordance with the US Army Military Police School (USAMPS) Concept of Employment and the PM-FPS MDARS Integrated Logistic Support Plan. The system was subjected to intensive periods of evaluation under the guidance and control of the Army Test and Evaluation Center (ATEC) and PM-FPS. Significantly, in terms of User acceptance, the system has been under the "operational control" of the installation performing security and force protection missions in support of daily operations. This evaluation is intended to assess MDARS operational effectiveness in an operational environment. Initial observations show that MDARS provides enhanced force protection, can potentially reduce manpower requirements by conducting routine tasks within its design capabilities and reduces Soldier exposure in the initial response to emerging incidents and situations. Success of the MDARS program has been instrumental in the design and development of two additional robotic force protection programs. The first was the USAF Force Protection Battle Lab sponsored Remote Detection Challenge & Response (REDCAR) concept demonstration executed by the Air Force Robotics Lab (AFRL). The REDCAR used an MDARS PUV as the central robotic technology and expanded the concept to incorporate a smaller high speed platform (SCOUT) equipped with lethal, non-lethal and challenge components as an engagement platform and, in a marsupial configuration on the MDARS, a small UGV that can be deployed to investigate close quarters areas. The Family of Integrated Rapid Response Equipment (FIRRE) program further expands these concepts by incorporating and adapting other mobile/tactical force protection equipment with a more robust Unmanned Ground Vehicle into an "Expeditionary" configuration to provide the current force with a rapidly deployable force protection system that can operate in austere less structured and protected environments. A USAMPS/ MANCEN sponsored "FIRRE System Demonstration" in Iraq is scheduled to begin in FY '07.
NASA's Gravitational - Wave Mission Concept Study
NASA Technical Reports Server (NTRS)
Stebbins, Robin; Jennrich, Oliver; McNamara, Paul
2012-01-01
With the conclusion of the NASA/ESA partnership on the Laser Interferometer Space Antenna (LISA) Project, NASA initiated a study to explore mission concepts that will accomplish some or all of the LISA science objectives at lower cost. The Gravitational-Wave Mission Concept Study consisted of a public Request for Information (RFI), a Core Team of NASA engineers and scientists, a Community Science Team, a Science Task Force, and an open workshop. The RFI yielded were 12 mission concepts, 3 instrument concepts and 2 technologies. The responses ranged from concepts that eliminated the drag-free test mass of LISA to concepts that replace the test mass with an atom interferometer. The Core Team reviewed the noise budgets and sensitivity curves, the payload and spacecraft designs and requirements, orbits and trajectories and technical readiness and risk. The Science Task Force assessed the science performance by calculating the horizons. the detection rates and the accuracy of astrophysical parameter estimation for massive black hole mergers, stellar-mass compact objects inspiraling into central engines. and close compact binary systems. Three mission concepts have been studied by Team-X, JPL's concurrent design facility. to define a conceptual design evaluate kt,y performance parameters. assess risk and estimate cost and schedule. The Study results are summarized.
Short-range components of nuclear forces: Experiment versus mythology
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kukulin, V. I.; Platonova, M. N., E-mail: platonova@nucl-th.sinp.msu.ru
2013-12-15
The present-day situation around the description of various (central, spin-orbit, and tensor) components of short-range nuclear forces is discussed. A traditional picture of these interactions based on the idea of one-meson exchange is contrasted against numerous results of recent experiments. As is shown in the present study, these results often deviate strongly from the predictions of traditional models. One can therefore state that such models are inapplicable to describing short-range nuclear forces and that it is necessary to go over from a traditional description to some alternative QCD-based (or QCD-motivated) picture. This means that, despite the widespread popularity of traditionalmore » concepts of short-range nuclear forces and their applicability in many particular cases, these concepts are not more than scientific myths that show their inconsistency when analyzed from the viewpoint of the modern experiment.« less
Liquid metal porous matrix sliding electrical contact: A concept
NASA Technical Reports Server (NTRS)
Ferguson, H.
1973-01-01
Concept utilizes porous metal or nonmetal matrix containing liquid metal in porous structure and confines liquid metal to contact area between rotor and brush by capillary forces. System may also be used to lubricate bearing systems.
Culture at work: Family therapy and the culture concept in post-World War II America.
Weinstein, Deborah F
2004-01-01
During the 1950s and 1960s, the concept of culture had currency beyond the disciplinary boundaries of anthropology and sociology. This article takes up a clinical example of the invocation of the culture concept by examining how early family therapists such as Nathan Ackerman, Murray Bowen, and Don Jackson used culture as a category of analysis during the formative years of their new field. The culture concept played an integral role in the processes by which family therapists simultaneously defined the object of their research and treatment, the family, and built their new field. Their varied uses of culture also contained tensions and contradictions, most notably between universal and relativist views of family and psychopathology and between views of family therapy as a conservative force for maintaining the nuclear family or a progressive force for overcoming social inequality. Copyright 2004 Wiley Periodicals, Inc.
Self-Induced Backaction Optical Pulling Force
NASA Astrophysics Data System (ADS)
Zhu, Tongtong; Cao, Yongyin; Wang, Lin; Nie, Zhongquan; Cao, Tun; Sun, Fangkui; Jiang, Zehui; Nieto-Vesperinas, Manuel; Liu, Yongmin; Qiu, Cheng-Wei; Ding, Weiqiang
2018-03-01
We achieve long-range and continuous optical pulling in a periodic photonic crystal background, which supports a unique Bloch mode with the self-collimation effect. Most interestingly, the pulling force reported here is mainly contributed by the intensity gradient force originating from the self-induced backaction of the object to the self-collimation mode. This force is sharply distinguished from the widely held conception of optical tractor beams based on the scattering force. Also, this pulling force is insensitive to the angle of incidence and can pull multiple objects simultaneously.
Proof of Concept Study: Investigating Force Metrics of an Intracorporeal Suturing Knot Task.
Wee, Justin; Azzie, Georges; Drake, James; Gerstle, J Ted
2018-06-19
Mastering proper force manipulation in minimally invasive surgery can take many hours of practice and training. Improper force control can lead to necrosis, infection, and scarring. A force-sensing skin (FSS) has been developed, which measures forces at the distal end of minimal access surgeries' (MAS) instruments without altering the instrument's structural integrity or the surgical workflow, and acts as a minimally disruptive add-on to any MAS instrument. A proof of concept study was conducted using a FSS-equipped 5 mm straight-tip needle holder. Participants (n = 19: 3 novices, 11 fellows, and 5 staff surgeons) performed one intracorporeal suturing knot task (ISKT). Using participant task video footage, each participant's two puncture forces (each wall of the Penrose drain) and three knot tightening forces were measured. Force metrics from the three expertise groups were compared using analysis of variance (ANOVA) and Tukey's honest significance test with statistical significance assessed at P < .05. Preliminary ISKT force metric data showed differences between novices and more experienced fellows and surgeons. Of the five stages of the ISKT evaluated, the first puncture force of the Penrose drain seemed to best reflect the difference in skill among participants. The study demonstrated ISKT knot tightening and puncture force ranges across three expertise levels (novices, surgical fellows, and staff surgeons) of 0.586 to 6.089 newtons (N) and 0.852 to 2.915 N, respectively. The investigation of force metrics is important for the implementation of future force feedback systems as it can provide real-time information to surgeons in training and the operating theater.
Optical force rectifiers based on PT-symmetric metasurfaces
NASA Astrophysics Data System (ADS)
Alaee, Rasoul; Gurlek, Burak; Christensen, Johan; Kadic, Muamer
2018-05-01
We introduce here the concept of optical force rectifier based on parity-time symmetric metasurfaces. Directly linked to the properties of non-Hermitian systems engineered by balanced loss and gain constituents, we show that light can exert asymmetric pulling or pushing forces on metasurfaces depending on the direction of the impinging light. This generates a complete force rectification in the vicinity of the exceptional point. Our findings have the potential to spark the design of applications in optical manipulation where the forces, strictly speaking, act unidirectionally.
Force sharing in high-power parallel servo-actuators
NASA Technical Reports Server (NTRS)
Neal, T. P.
1974-01-01
The various existing force sharing schemes were examined by conducting a literature survey. A list of potentially applicable concepts was compiled from this survey, and a brief analysis was then made of each concept, which resulted in two competing schemes being selected for in-depth evaluation. A functional design of the equalization logic for the two schemes was undertaken and specific space shuttle application was chosen for experimental evaluation. The application was scaled down so that existing hardware could be utilized. Next, an analog computer study was conducted to evaluate the more important characteristics of the two competing force sharing schemes. On the basis of the computers study, a final configuration was selected. A load simulator was then designed to evaluate this configuration on actual hardware.
Students' Concept of Force: The Importance of Understanding Newton's Third Law.
ERIC Educational Resources Information Center
Brown, David E.
This paper analyzes the misconceptions high school students have about force and suggests that the misunderstanding of Newton's third law is the key to these misconceptions. Clinical interview and diagnostic test data (N=104) indicates that many students have a naive view of force as an acquired or innate property of single objects rather than…
Non-Uniqueness of the Point of Application of the Buoyancy Force
ERIC Educational Resources Information Center
Kliava, Janis; Megel, Jacques
2010-01-01
Even though the buoyancy force (also known as the Archimedes force) has always been an important topic of academic studies in physics, its point of application has not been explicitly identified yet. We present a quantitative approach to this problem based on the concept of the hydrostatic energy, considered here for a general shape of the…
ERIC Educational Resources Information Center
Gale, Jessica; Wind, Stefanie; Koval, Jayma; Dagosta, Joseph; Ryan, Mike; Usselman, Marion
2016-01-01
This paper illustrates the use of simulation-based performance assessment (PA) methodology in a recent study of eighth-grade students' understanding of physical science concepts. A set of four simulation-based PA tasks were iteratively developed to assess student understanding of an array of physical science concepts, including net force,…
ERIC Educational Resources Information Center
Quilez, Juan
2009-01-01
With this paper, our main aim is to contribute to the realisation of the chemical reactivity concept, tracing the historical evolution of the concept of chemical affinity that eventually supported the concept of chemical equilibrium. We will concentrate on searching for the theoretical grounds of three key chemical equilibrium ideas: "incomplete…
Pasipoularides, Ares
2015-01-01
Epigenetic mechanisms are fundamental in cardiac adaptations, remodeling, reverse remodeling, and disease. This 2-article series proposes that variable forces associated with diastolic RV/LV rotatory intraventricular flows can exert physiologically and clinically important, albeit still unappreciated, epigenetic actions influencing functional and morphological cardiac adaptations and/or maladaptations. Taken in-toto, the 2-part survey formulates a new paradigm in which intraventricular diastolic filling vortex-associated forces play a fundamental epigenetic role, and examines how heart cells react to these forces. The objective is to provide a perspective on vortical epigenetic effects, to introduce emerging ideas and suggest directions of multidisciplinary translational research. The main goal is to make pertinent biophysics and cytomechanical dynamic systems concepts accessible to interested translational and clinical cardiologists. I recognize that the diversity of the epigenetic problems can give rise to a diversity of approaches and multifaceted specialized research undertakings. Specificity may dominate the picture. However, I take a contrasting approach. Are there concepts that are central enough that they should be developed in some detail? Broadness competes with specificity. Would however this viewpoint allow for a more encompassing view that may otherwise be lost by generation of fragmented results? Part 1 serves as a general introduction, focusing on background concepts, on intracardiac vortex imaging methods, and on diastolic filling vortex-associated forces acting epigenetically on RV/LV endocardium and myocardium. Part 2 will describe pertinent available pluridisciplinary knowledge/research relating to mechanotransduction mechanisms for intraventricular diastolic vortex forces and myocardial deformations and to their epigenetic actions on myocardial and ventricular function and adaptations. PMID:25624114
An Analysis of Air Force Management of Turbine Engine Monitoring Systems (TEMS).
1980-06-01
AIR FORCE AIR UNIVERSITY (ATC) C AIR FORCE INSTITUTE OF TECHNOLOGY LWright-Patterson Air Force Base, Ohio 80 9 22 057 All BBO RCE j GEMEM Elbert B...detrimental ideas, or deleterious information are contained therein. Furthermore, the views expressed in the document are those of the author(s) and...role problems, information flow and integration problems, and leadership and command problems. Four alternative management concepts were analyzed. Based
2008-07-28
continue to be beyond our technical ability to realize aggresively pursue advanced technical solutions to stay at the leading edge of technological...inherent to each caf Way and to seek continual improvement through exploration of innovative concepts, advanced capabilities, game -changing...available online at the air force portal: https://wwwd.my.af.mil/afknprod/strat_plan COMBAT AIR FORCE STRATEGIC PLAN Points of Contact securing the high
NASA Astrophysics Data System (ADS)
Joung, Yong Jae; Gunstone, Richard
2010-08-01
Typically-Perceived-Situation (TPS) refers to the situation rising spontaneously in an individual's mind when she/he first thinks of a phenomenon or concept. The purpose of this study is to go well beyond the many studies that describe conceptions of force and explore children's TPS of "force is acting on a thing" and "force is not acting on a thing", and to do this in the differing contexts of Australia and Korea. Data were collected by drawings and written explanations from 145 Grade 6 Australian children and 150 Grade 6 Korean children. These data showed some significant differences between the Australian children's and Korean children's TPSs. For example, considering the whole context of children's TPS, the contexts of "someone pushes or pulls something" and "someone/something is floating in the air or not moving because there is no gravity" were the most frequent ones, as a "force" and as a "no force" situation respectively, in the case of Australian children, while "a sort of energy is provided into someone/something and they can be active/working" and "a sort of energy is not provided into someone/something and they cannot be active/working", were most frequent in the case of Korean children. These differences are very likely the consequence of different everyday meanings for the word "force" in the two cultures. In addition, it appears that these children's TPS affect their judgement of "force" and "no force".
Conceptions of ability as stable and self-evaluative processes: a longitudinal examination.
Pomerantz, E M; Saxon, J L
2001-01-01
It has generally been taken for granted that conceiving of ability as stable leads to negative self-evaluative processes, particularly in the face of failure. Yet, a close examination of the empirical findings suggests that the picture may be more complex. In this research, a three-wave longitudinal design spanning 12 months was employed. Older elementary school children (N = 932) indicated their conceptions of academic and social ability as stable to external forces and to internal forces. They also provided information about the importance they place on academic and social competence, their knowledge about academic and social performance, their preference for academic challenge, their perceptions of academic and social competence, and their attributions for academic and social performance. Children's grades in school and their acceptance by peers were obtained as indicators of performance. Over time, conceiving of ability as stable to external forces, particularly in the academic domain, appeared to heighten the importance placed on competence, performance knowledge, preference for challenge, perceptions of competence, and self-enhancing attributions. In contrast, conceptions of ability as stable to internal forces, particularly in the academic domain, appeared to be fostered by placing little importance on competence, a lack of performance knowledge, avoidance of challenge, negative perceptions of competence, self-deprecating attributions, and poor performance.
Students' Development of Representational Competence Through the Sense of Touch
NASA Astrophysics Data System (ADS)
Magana, Alejandra J.; Balachandran, Sadhana
2017-06-01
Electromagnetism is an umbrella encapsulating several different concepts like electric current, electric fields and forces, and magnetic fields and forces, among other topics. However, a number of studies in the past have highlighted the poor conceptual understanding of electromagnetism concepts by students even after instruction. This study aims to identify novel forms of "hands-on" instruction that can result in representational competence and conceptual gain. Specifically, this study aimed to identify if the use of visuohaptic simulations can have an effect on student representations of electromagnetic-related concepts. The guiding questions is How do visuohaptic simulations influence undergraduate students' representations of electric forces? Participants included nine undergraduate students from science, technology, or engineering backgrounds who participated in a think-aloud procedure while interacting with a visuohaptic simulation. The think-aloud procedure was divided in three stages, a prediction stage, a minimally visual haptic stage, and a visually enhanced haptic stage. The results of this study suggest that students' accurately characterized and represented the forces felt around a particle, line, and ring charges either in the prediction stage, a minimally visual haptic stage or the visually enhanced haptic stage. Also, some students accurately depicted the three-dimensional nature of the field for each configuration in the two stages that included a tactile mode, where the point charge was the most challenging one.
2005-09-01
Command – Space and Global Strike JFCOM Joint Forces Command JFRL Joint Forces Restricted Frequency List JIC Joint Integrating Concept JIM Joint...into the theater’s Joint Restricted Frequency List (JRFL). The ARSST trained the coalition and US soldiers on installation, use and troubleshooting
Understanding Productivity Links: A Research Agenda.
ERIC Educational Resources Information Center
Stevens, David
1981-01-01
This paper covers three fundamental aspects of productivity analysis: concepts, measurement issues, and a brief consideration of causal forces. It also explores recent trends in partial labor productivity, building on terms and concepts introduced in the first part of this article. (CT)
Newton's Law: Not so Simple after All
ERIC Educational Resources Information Center
Robertson, William C.; Gallagher, Jeremiah; Miller, William
2004-01-01
One of the most basic concepts related to force and motion is Newton's first law, which essentially states, "An object at rest tends to remain at rest unless acted on by an unbalanced force. An object in motion in a straight line tends to remain in motion in a straight line unless acted upon by an unbalanced force." Judging by the time and space…
Relationships Among an Individual Intelligence Test and Two Air Force Screening and Selection Tests.
ERIC Educational Resources Information Center
McGrevy, David F.; And Others
With the implementation of the all volunteer force concept, the Air Force must ensure that the objectively measurable range of ability in its manpower pool is being utilized. This is especially true for minority groups who have been categorized and channeled into military career areas based on their performance on two selection tests: the Armed…
ERIC Educational Resources Information Center
Nousiainen, Maija; Koponen, Ismo T.
2017-01-01
The concepts of electricity and magnetism in physics are complex and demanding to learn because their meaning builds through several different phenomenological areas. Each of the phenomenological areas adds a certain facet of the meaning of the concept. All standard physics textbooks discuss at least 1) force, 2) energy and work, and 3) electric…
ERIC Educational Resources Information Center
Küçüközer, Asuman
2006-01-01
This study aims to better understand the construction of the meaning of physics concepts in mechanics during a teaching sequence at the upper secondary school level. In the teaching sessions, students were introduced to the concepts of interaction and force. During this teaching sequence the models called "interactions" and "laws of…
Teaching the Concept of Resonance with the Help of a Classical Guitar
NASA Astrophysics Data System (ADS)
Kasar, M. Kaan; Yurumezoglu, Kemal; Sengoren, Serap Kaya
2012-12-01
Resonance refers to the vibrations of larger amplitude that are produced under the effect of a harmonic driving force. Although resonance is an essential concept behind many events happening in nature, students usually have difficulty in learning and explaining the phenomenon. Various demonstrations are carried out in physics classes to clarify the concept of resonance.2-6
NASA Astrophysics Data System (ADS)
Rincke, Karsten
2011-01-01
Although a broad literature exists concerning the development of conceptual understanding of force and other topics within mechanics, little is known about the role and development of students' talk about the subject. The paper presents an in-depth investigation of students' talk whilst being introduced to the concept of force. The main research goal was to investigate and understand how students develop an understanding of the concept of force and how they use and understand the term 'force'. Therefore, we make relation to the research field of students' preconceptions and the field of second language learning. Two classes of students (N = 47) were videotaped during a time period of nine lessons, each transcribed and analysed using a category system. Additional data were obtained via written tasks, logs kept by the students, and tests. The detailed analysis of the talk and the results of the tests indicate that students face difficulties in using the term 'force' scientifically similar to those in a foreign language instruction. Vygotsky already recognised a relationship between learning in science and learning a language. In this paper, important aspects of this relationship are discussed based upon empirical data. We conclude that in some respects it might be useful to make reference to the research related to language learning when thinking about improving science education. In particular, according to Selinker's concept of interlanguage describing language-learning processes within language instruction, the language used by the students during physics lessons can be viewed as a 'scientific interlanguage'.
Examining evolving performance on the Force Concept Inventory using factor analysis
NASA Astrophysics Data System (ADS)
Semak, M. R.; Dietz, R. D.; Pearson, R. H.; Willis, C. W.
2017-06-01
The application of factor analysis to the Force Concept Inventory (FCI) has proven to be problematic. Some studies have suggested that factor analysis of test results serves as a helpful tool in assessing the recognition of Newtonian concepts by students. Other work has produced at best ambiguous results. For the FCI administered as a pre- and post-test, we see factor analysis as a tool by which the changes in conceptual associations made by our students may be gauged given the evolution of their response patterns. This analysis allows us to identify and track conceptual linkages, affording us insight as to how our students have matured due to instruction. We report on our analysis of 427 pre- and post-tests. The factor models for the pre- and post-tests are explored and compared along with the methodology by which these models were fit to the data. The post-test factor pattern is more aligned with an expert's interpretation of the questions' content, as it allows for a more readily identifiable relationship between factors and physical concepts. We discuss this evolution in the context of approaching the characteristics of an expert with force concepts. Also, we find that certain test items do not significantly contribute to the pre- or post-test factor models and attempt explanations as to why this is so. This may suggest that such questions may not be effective in probing the conceptual understanding of our students.
Central distractors in Force Concept Inventory data
NASA Astrophysics Data System (ADS)
Scott, Terry F.; Schumayer, Dániel
2018-01-01
The Force Concept Inventory was designed to poll the Newtonian conception of force. While there are many in-depth studies analyzing response data that look at the structure of the correct answers, we believe that the incorrect answers also carry revealing information about the students' worldview. The inventory was originally designed so that the "distractors" in each question reflected commonly held misconceptions, and thus the rate at which students guess the correct answer is very low. Students select incorrect answers that correspond to the misconception that they hold and there are very few responses which appear obviously wrong to students. A side effect of this approach is that the incorrect responses reflect the non-Newtonian worldviews held by students. These non-Newtonian worldviews are coherent and robust, and this, at least in part, helps to explain why these misconceptions are so resistant to instruction. In this study we focus once more on the misconception data in Force Concept Inventory responses, particularly on the linkages between these misconceptions. We hypothesize that there are distinct groupings of distractor items formed by the strength of the association between these items. The two largest groupings are associated with the "impetus" world view in which the motion of an object is determined by the quantity of impetus which that object contains. We find that certain central items hold particularly important places in these groupings and also that individual groupings may be connected to each other by "connector" items. We finally suggest that, on the basis of this study, that these non-Newtonian worldviews might best be dismantled by addressing these key central and connector items.
Desert Talons: Historical Perspectives and Implications of Air Policing in the Middle East
2009-04-01
predominant role in support of a smaller ground force has historical precedent. During the 1920s, the Royal Air Forces (RAF) air control method adhered...the Royal Air Force’s (RAF) air control method adhered to the concepts of the inverted blockade, minimum force, precision targeting, and force...owing to its process of rapid communications, Air Methods are, in short, the reverse of the old punitive column. Our policy is one of prevention
Dynamics and stability of mechanical systems with follower forces
NASA Technical Reports Server (NTRS)
Herrmann, G.
1971-01-01
A monograph on problems of stability of equilibrium of mechanical systems with follower forces is presented. Concepts of stability and criteria of stability are reviewed briefly, together with means of analytical specification of follower forces. Nondissipative systems with two degrees of freedom are discussed, and destabilizing effects due to various types of dissipative forces both in discrete and continuous systems, are treated. The analyses are accompanied by some quantative experiments and observations on demonstrational laboratory models.
Mobile Firepower for Contingency Operations: Emerging Concepts for U.S. Army Light Armor Forces
1993-02-04
Industries ’ VBM," Internationa Defense 25 (June 1992): 575. ’Herbert M. Howe, "Can the South African Defense Force Go it Alone?" Armed Forces Journal ...necessary for mission accomplishment." Support and sustainment operations include provision of fuel, maintenance, and ammunition for the deployed force. 4...headquarters troop (Hil), a chemical company, an air defense artillery battery, an engineer company, a military intelligence company, a non-fine-of-sight anti
Application of active control landing gear technology to the A-10 aircraft
NASA Technical Reports Server (NTRS)
Ross, I.; Edson, R.
1983-01-01
Two concepts which reduce the A-10 aircraft's wing/gear interface forces as a result of applying active control technology to the main landing gear are described. In the first concept, referred to as the alternate concept a servovalve in a closed pressure control loop configuration effectively varies the size of the third stage spool valve orifice which is embedded in the strut. This action allows the internal energy in the strut to shunt hydraulic flow around the metering orifice. The command signal to the loop is reference strut pressure which is compared to the measured strut pressure, the difference being the loop error. Thus, the loop effectively varies the spool valve orifice size to maintain the strut pressure, and therefore minimizes the wing/gear interface force referenced.
NASA Astrophysics Data System (ADS)
Preiss, Bruce; Greene, Lloyd; Kriebel, Jamie; Wasson, Robert
2006-05-01
The Air Force Research Laboratory utilizes a value model as a primary input for space technology planning and budgeting. The Space Sector at AFRL headquarters manages space technology investment across all the geographically disparate technical directorates and ensures that integrated planning is achieved across the space community. The space investment portfolio must ultimately balance near, mid, and far-term investments across all the critical space mission areas. Investment levels and growth areas can always be identified by a typical capability analysis or gap analysis, but the value model approach goes one step deeper and helps identify the potential payoff of technology investments by linking the technology directly to an existing or potential concept. The value of the technology is then viewed from the enabling performance perspective of the concept that ultimately fulfills the Air Force mission. The process of linking space technologies to future concepts and technology roadmaps will be reviewed in this paper, along with representative results from this planning cycle. The initial assumptions in this process will be identified along with the strengths and weaknesses of this planning methodology.
The compression dome concept: the restorative implications.
Milicich, Graeme
2017-01-01
Evidence now supports the concept that the enamel on a tooth acts like a compression dome, much like the dome of a cathedral. With an overlying enamel compression dome, the underlying dentin is protected from damaging tensile forces. Disruption of a compression system leads to significant shifts in load pathways. The clinical restorative implications are significant and far-reaching. Cutting the wrong areas of a tooth exposes the underlying dentin to tensile forces that exceed natural design parameters. These forces lead to crack propagation, causing flexural pain and eventual fracture and loss of tooth structure. Improved understanding of the microanatomy of tooth structure and where it is safe to cut teeth has led to a revolution in dentistry that is known by several names, including microdentistry, minimally invasive dentistry, biomimetic dentistry, and bioemulation dentistry. These treatment concepts have developed due to a coalescence of principles of tooth microanatomy, material science, adhesive dentistry, and reinforcing techniques that, when applied together, will allow dentists to repair a compromised compression dome so that it more closely replicates the structure of the healthy tooth.
Haeufle, D F B; Günther, M; Blickhan, R; Schmitt, S
2011-01-01
Recently, the hyperbolic Hill-type force-velocity relation was derived from basic physical components. It was shown that a contractile element CE consisting of a mechanical energy source (active element AE), a parallel damper element (PDE), and a serial element (SE) exhibits operating points with hyperbolic force-velocity dependency. In this paper, the contraction dynamics of this CE concept were analyzed in a numerical simulation of quick release experiments against different loads. A hyperbolic force-velocity relation was found. The results correspond to measurements of the contraction dynamics of a technical prototype. Deviations from the theoretical prediction could partly be explained by the low stiffness of the SE, which was modeled analog to the metal spring in the hardware prototype. The numerical model and hardware prototype together, are a proof of this CE concept and can be seen as a well-founded starting point for the development of Hill-type artificial muscles. This opens up new vistas for the technical realization of natural movements with rehabilitation devices. © 2011 IEEE
Breaking the Status Quo: Information and the Future Force
2012-03-12
Bonds. Hollywood rolled out Movietone news releases before every cinema offering, and stalwarts such as Frank Capra produced films destined to stir...report commissioned by the French Joint Forces Centre for Concept Development, Doctrine, and Experimentation – recommended that France adopt this
Free (Reactionless) Torque Generation—Or Free Propulsion Concept
NASA Astrophysics Data System (ADS)
Djordjev, Bojidar
2010-01-01
The basic principle in Newtonian Mechanics is based upon equal and opposite forces. Placing the vectors of velocity, acceleration, force and momentum of interacting objects along a single line satisfies the claim it is a linear or a 1-D concept. Classical Mechanics states that there are two main kinds of motion, linear and angular motion. Similarly placing the vectors of angular velocity, angular acceleration, torque and angular momentum along a line in the case of rotation in fact brings a plane 2-D interaction to the well known 1-D Newtonian concept. This adaptation transforms Classical Mechanics into a 1-D concept as well and presents a conformation that the linear concept is the only possible one. The Laws of Conservation of Momentum and Angular Momentum are results of the 1-D concept. But the world contains 3 geometrical spatial dimensions. Within the 3-D world there can exist 1-D, 2-D and 3-D kinds of interaction. The question is how to believe that the 3-D world can really be composed of a 1-D interaction or interactions made equal to the 1-D concept only? Examine a gyroscope—the only one mechanical device that is capable of performng 3-D behavior. The problem is that a gyroscope cannot perform three permanent and unidirectional torques that are fixed in space acting about perpendicular axes. This impossibility conforms to a 1-D concept. The idea is to find a solution that can be achieved for the 3-D concept.
The Prediction of the Work of Friction Force on the Arbitrary Path
ERIC Educational Resources Information Center
Matehkolaee, Mehdi Jafari; Majidian, Kourosh
2013-01-01
In this paper we have calculated the work of friction force on the arbitrary path. In our method didn't use from energy conservative conceptions any way. The distinction of this procedure is that at least do decrease measurement on the path once. Thus we can forecast the amount of work of friction force without information about speed of…
ERIC Educational Resources Information Center
Bani-Salameh, Hisham N.
2017-01-01
We started this work with the goal of detecting misconceptions held by our students about force and motion. A total of 341 students participated in this study by taking the force concept inventory (FCI) test both before and after receiving instructions about force or motion. The data from this study were analysed using different statistical…
2008-03-01
Jasmine , you have sacrificed daddy for countless hours and weekends when I was required to study. At times, it was overwhelming and seemed as if it...by leveraging the 8 command and control advantage enjoyed by U. S. forces. The article stated that “The essence of this concept lies in the
2001-03-01
characteristics shown in Table 1 are based upon a conventional armoured formation, and implicitly at divisional level or above, they could also apply at lower...widely dispersed Ease of Physical big/hot mid-size/cool small/cold targeting Camouflage scrimmed draped visual full/thermal EMCON 4 3 2 1 Visibility...line of sight occulting/obscured non line of sight Contact static FLOT fluid confused melée Armour soft semi-hard hard defensive aids Protection
Turbofan forced mixer lobe flow modeling. Part 3: Application to augment engines
NASA Technical Reports Server (NTRS)
Barber, T.; Moore, G. C.; Blatt, J. R.
1988-01-01
Military engines frequently need large quantities of thrust for short periods of time. The addition of an augmentor can provide such thrust increases but with a penalty of increased duct length and engine weight. The addition of a forced mixer to the augmentor improves performance and reduces the penalty, as well as providing a method for siting the required flame holders. In this report two augmentor concepts are investigated: a swirl-mixer augmentor and a mixer-flameholder augmentor. Several designs for each concept are included and an experimental assessment of one of the swirl-mixer augmentors is presented.
A Magnetically Suspended Wheel for a Miniature Gyro Made Using Planar Fabrication Technologies
NASA Technical Reports Server (NTRS)
Dauwalter, Charles R.
1996-01-01
The technical feasibility of a magnetically suspended rotating wheel for miniature gyro applications was investigated under a NASA SBIR contract. A concept for a configuration for a system of compact, lightweight magnetic actuators capable of generating the necessary suspension forces and fabrication using millimachining planar fabrication technologies was developed. Both capacitive and electromagnetic position sensing concepts were developed for implementing a closed loop control system for supporting the wheel. A finite difference technique, implemented in a spreadsheet environment, for analyzing the force characteristics of the actuator was used and the results verified with Finite Element Analysis.
ERIC Educational Resources Information Center
Wolff, Phillip
2007-01-01
The dynamics model, which is based on L. Talmy's (1988) theory of force dynamics, characterizes causation as a pattern of forces and a position vector. In contrast to counterfactual and probabilistic models, the dynamics model naturally distinguishes between different cause-related concepts and explains the induction of causal relationships from…
1988-01-01
by the United States Air Force under Contract F49620-86-C-0008. Further information may be obtained from the Long Range Planning and Doctrine Division...published simultaneously with this Note. The work was performed under the Project AIR FORCE project entitled "Concept Development and Project Formulation...warfare aircraft, and 130 ground attack fighters. Norway can field a total armed force of about 366,500 men under a system of universal conscription and
Entropic forces in Brownian motion
NASA Astrophysics Data System (ADS)
Roos, Nico
2014-12-01
Interest in the concept of entropic forces has risen considerably since Verlinde proposed in 2011 to interpret the force in Newton's second law and gravity as entropic forces. Brownian motion—the motion of a small particle (pollen) driven by random impulses from the surrounding molecules—may be the first example of a stochastic process in which such forces are expected to emerge. In this article, it is shown that at least two types of entropic force can be identified in three-dimensional Brownian motion. This analysis yields simple derivations of known results of Brownian motion, Hooke's law, and—applying an external (non-radial) force—Curie's law and the Langevin-Debye equation.
Assessment of Advanced Logistics Delivery System (ALDS) Launch Systems Concepts
2004-10-01
highest force vs. rotor weight required, allows much higher magnetic field generation than the linear induction or linear permanent magnet motors , and...provides the highest force vs. rotor weight required, allows much higher magnetic generation than the linear induction or linear permanent magnet motors , and
Situational Marketing: Application for Higher Education Institutions.
ERIC Educational Resources Information Center
Taylor, Raymond E.; Reed, Rosetta R.
1995-01-01
Marketing higher education has been criticized for its consumer (interpreted as student) orientation. An alternative concept, situational marketing, considers the student as one of a number of environmental forces on which the marketing mix focuses. Other forces include funding and regulatory agencies, businesses, alumni, faculty, parents, the…
Characterizing Students' Mechanistic Reasoning about London Dispersion Forces
ERIC Educational Resources Information Center
Becker, Nicole; Noyes, Keenan; Cooper, Melanie
2016-01-01
Characterizing how students construct causal mechanistic explanations for chemical phenomena can provide us with important insights into the ways that students develop understanding of chemistry concepts. Here, we present two qualitative studies of undergraduate general chemistry students' reasoning about the causes of London dispersion forces in…
Competitive forces in the medical group industry: a stakeholder perspective.
Blair, J D; Buesseler, J A
1998-01-01
Applying Porter's model of competitive forces to health care, stakeholder concepts are integrated to analyze the future of medical groups. Using both quantitative survey and qualitative observational data, competitors, physician suppliers, integrated systems new entrants, patient and managed care buyers, and hospitals substitutes are examined.
Core drill's bit is replaceable without withdrawal of drill stem - A concept
NASA Technical Reports Server (NTRS)
Rushing, F. C.; Simon, A. B.
1970-01-01
Drill bit is divided into several sectors. When collapsed, the outside diameter is forced down the drill stem, when it reaches bottom the sectors are forced outward and form a cutting bit. A dulled bit is retracted by reversal of this procedure.
Climatic Concepts and Regions.
ERIC Educational Resources Information Center
Thomas, Paul F.
Designed for students in grades 7 through 12, this teaching unit presents illustrative resource materials depicting concepts related to climate and geographic regions. Emphasis is on giving students an understanding of climatic elements and factors, not as isolated, disjointed entities, but as a dynamic interplay of forces having a very definite…
The Public Telecommunications Network: A Concept in Transition.
ERIC Educational Resources Information Center
Noam, Eli M.
1987-01-01
Argues that the traditional centralized model of the public telecommunication networks is being undermined by a host of centrifugal forces, and that a new and open network concept is emerging that breaks down the dichotomy between the telecommunications sector and the rest of the economy. (JD)
ERIC Educational Resources Information Center
Valadakis, Andreas
2014-01-01
Although we experience motion simply as displacement, we study it through complicated concepts such as acceleration, force, and mass, departing from our everyday experience. But it looks like we can stay attached to our primordial notions of time and length without appealing to any other concepts and still have interesting results.
American Indian Religion: Past, Present, Future.
ERIC Educational Resources Information Center
Stewart, Omer C.
1980-01-01
Describes the basic concept of American Indian religion after briefly comparing fundamental religious concepts of several civilizations. Discusses the historical and current roles of medicine men, the belief in supernatural forces, the effect of missionary zeal on American Indian religions, and the appearance of Christian elements in traditional…
USAF/SCEEE Graduate Student Summer Research Program (1984). Program Management Report.
1984-10-01
adjunct effort to the SFRP. Its purpose is to provide funds for selected graduate students to do research at an appropriate Air Force laboratory or...under the Summer Faculty Research Program or an Air Force laboratory designated *- colleague. The students were U.S. citizens, working toward . an...faculty member; excellent laboratory experience. Good opportunity to become acquainted with Air Force research . Good concept. Good stipend
Evaluating the Validity of the U.S. Military’s Global Empire
2015-03-26
With this status came an unchecked and impressive global force posture . While the United States dramatically cut the number of personnel in Western...evaluates the currant pre-positioned equipment concepts, and evaluates Operation Enduring Freedom (Afghanistan) as a case study for Force Posture . The...conclusion offers five recommendations for the future of United States global force posture and actions that support access. 15. SUBJECT TERMS 16
Effective Coulomb force modeling for spacecraft in Earth orbit plasmas
NASA Astrophysics Data System (ADS)
Seubert, Carl R.; Stiles, Laura A.; Schaub, Hanspeter
2014-07-01
Coulomb formation flight is a concept that utilizes electrostatic forces to control the separations of close proximity spacecraft. The Coulomb force between charged bodies is a product of their size, separation, potential and interaction with the local plasma environment. A fast and accurate analytic method of capturing the interaction of a charged body in a plasma is shown. The Debye-Hückel analytic model of the electrostatic field about a charged sphere in a plasma is expanded to analytically compute the forces. This model is fitted to numerical simulations with representative geosynchronous and low Earth orbit (GEO and LEO) plasma environments using an effective Debye length. This effective Debye length, which more accurately captures the charge partial shielding, can be up to 7 times larger at GEO, and as great as 100 times larger at LEO. The force between a sphere and point charge is accurately captured with the effective Debye length, as opposed to the electron Debye length solutions that have errors exceeding 50%. One notable finding is that the effective Debye lengths in LEO plasmas about a charged body are increased from centimeters to meters. This is a promising outcome, as the reduced shielding at increased potentials provides sufficient force levels for operating the electrostatically inflated membrane structures concept at these dense plasma altitudes.
Magnetohydrodynamic (MHD) Magnet Modeling
1979-06-01
Relationship /4 to Structural Teeth and Cold Bore Tube 56 Force Cý.mponents on Saddlc Winding 84 57 Quarter Section of Magnet nesign at Midplane 85 58...Graphite/Epoxy Filament Wound 184 A-2 Concept B - Boron /Aluminum Structure 186 A-3 Concept i - Graphite/Epoxy Structure 187 A-4 Initial Stress Analysis...Wound A-15 MHD Magnet Modeling Manufacturing Sequence 205 Concept B - Boron /Aluminum Structure A-16 MHD Magnet Modeling Manufacturing Sequence 206
Energy absorption studied to reduce aircraft crash forces
NASA Technical Reports Server (NTRS)
1981-01-01
The NASA/FAA aircraft safety reseach programs for general aviation aircraft are discussed. Energy absorption of aircraft subflooring and redesign of interior flooring are being studied. The testing of energy absorbing configurations is described. The three NASA advanced concepts performed at neary the maximum possible amount of energy absorption, and one of two minimum modifications concepts performed well. Planned full scale tests are described. Airplane seat concepts are being considered.
On the Concept of Energy: Eclecticism and Rationality
NASA Astrophysics Data System (ADS)
Coelho, Ricardo Lopes
2014-06-01
In the theory of heat of the first half of the nineteenth century, heat was a substance. Mayer and Joule contradicted this thesis but developed different concepts of heat. Heat was a force for Mayer and a motion for Joule. Both Mayer and Joule determined the mechanical equivalent of heat. This result was, however, justified in accordance with those concepts of heat. Mayer's characterisation of force reappears in the very common textbook definition `energy cannot be created or destroyed but only transformed' and his theory led to a phenomenological approach to energy. Joule and Thomson's concept of heat led to a mechanistic approach to energy and to the common definition `energy is the capacity of doing work'. One and the same term `energy' subsumed these two approaches. The problematic concept of energy, energy as a substance, appears then as a result of an eclectic development of the concept. Another approach, which appeared in the 1860s, is directly based on the mechanical equivalent of heat and can be characterized by the use of `principle of equivalence' instead of `principle of energy conservation'. Unlike the others, this approach, which has been lost, poses no problems with the concept of energy. The problems with the energy concept as to the kind of phenomena dealt with in the present paper can, however, be overcome, as we shall see, in distinguishing between that which comes from experiments and that which is an interpretation of the experimental results within a conceptual framework.
Inservice Elementary and Middle School Teachers' Conceptions of Photosynthesis and Respiration
NASA Astrophysics Data System (ADS)
Krall, Rebecca Mcnall; Lott, Kimberly H.; Wymer, Carol L.
2009-02-01
The purpose of this descriptive study was to investigate inservice elementary and middle school teachers’ conceptions of photosynthesis and respiration, basic concepts they are expected to teach. A forced-choice instrument assessing selected standards-based life science concepts with non-scientific conceptions embedded in distracter options was utilized to assess 76 inservice elementary and middle school teachers from the central Appalachian region. Outcomes from four tasks assessing photosynthesis and respiration concepts are discussed. Findings revealed similarities between non-scientific conceptions the teachers demonstrated and non-scientific conceptions reported in the research literature on elementary and middle school students’ understanding of the concepts. Findings also informed subsequent inservice teacher professional development efforts in life science and the development of a biology course for preservice elementary teachers.
Theory of Aircraft Flight. Aerospace Education II.
ERIC Educational Resources Information Center
Glascoff, W. G., III
The textbook provides answers to many questions related to airplanes and properties of air flight. The first chapter provides a description of aerodynamic forces and deals with concepts such as acceleration, velocity, and forces of flight. The second chapter is devoted to the discussion of properties of the atmosphere. How different…
The Forces Restructuring Our Future and Outdoor Recreation: Transcription of Keynote Speech.
ERIC Educational Resources Information Center
Feather, Frank
This futurist keynote speech of the National Conference for Outdoor Leaders addresses the social, technological, economic, and political forces that are restructuring the world. The concept of geostrategic thinking has the components of global thinking, futuristic thinking, and seeking opportunities. Important developments include: (1) wealth will…
Reciprocating Linear Electric Motor
NASA Technical Reports Server (NTRS)
Goldowsky, M. P.
1984-01-01
Features include structural simplicity and good force/displacement characteristics. Reciprocating motor has simple, rugged construction, relatively low reciprocating weight, improved power delivery, and improved force control. Wear reduced by use of magnetic bearings. Intended to provide drivers for long-lived Stirling-cycle cryogenic refrigerators, concept has less exotic applications, such as fuel pumps.
Gyroscopic Motion: Show Me the Forces!
ERIC Educational Resources Information Center
Kaplan, Harvey; Hirsch, Andrew
2014-01-01
Gyroscopes are frequently used in physics lecture demonstrations and in laboratory activities to teach students about rotational dynamics, namely, angular momentum and torque. Use of these powerful concepts makes it difficult for students to fully comprehend the mechanism that keeps the gyroscope from falling under the force of gravity. The…
A Mobilization Concept for the Future
1989-04-28
ecnomic , mili-ary and political factors that T7haro the :omcsition of U.S. Army force structure and troop taticning. Further, in the interest of cost...be based on mission essential task lists (METL) for specific geographic areas. As a beginning, the Army should look at developing two such forces. One
New Concepts for the Development of Carbon Nanotube Materials for Army Related Applications
2015-08-16
the microcavity exciton- polariton system, which started as a theoretical concept in the 1990s and has been a driving force for experimental physics of... polariton lasers, optical polarization switches, superfluid spintronic devices, etc. We, therefore, strongly believe that the quasi-1D exciton BEC effect
Project Physics Text 1, Concepts of Motion.
ERIC Educational Resources Information Center
Harvard Univ., Cambridge, MA. Harvard Project Physics.
Fundamental concepts of motion are presented in this first unit of the Project Physics textbook. Descriptions of motion are made in connection with speeds, accelerations, and their graphical representation. Free-fall bodies are analyzed by using Aristotle's theory and Galileo's work. Dynamics aspects are discussed with a background of mass, force,…
Project Physics Tests 1, Concepts of Motion.
ERIC Educational Resources Information Center
Harvard Univ., Cambridge, MA. Harvard Project Physics.
Test items relating to Project Physics Unit 1 are presented in this booklet, consisting of 70 multiple-choice and 20 problem-and-essay questions. Concepts of motion are examined with respect to velocities, acceleration, forces, vectors, Newton's laws, and circular motion. Suggestions are made for time consumption in answering some items. Besides…
Liquid Crystals: The Phase of the Future.
ERIC Educational Resources Information Center
Ondris-Crawford, Renate; And Others
1992-01-01
Liquid crystal displays are currently utilized to convey information via graphic displays. Presents experiments and explanations that employ the concept of liquid crystals to learn concepts related to the various states of matter, electric and magnetic forces, refraction of light, and optics. Discusses applications of liquid crystal technology.…
Reproductive cell separation: A concept
NASA Technical Reports Server (NTRS)
Cutaia, A. J.
1973-01-01
Attempt has been made to separate mammalian male (Y) bearing sperm from female (X) bearing sperm. Both types of sperm are very dependent on gravity for their direction of movement. Proposed concept suggests electrophoretic force of suitable magnitude and direction may be effective means of separating X and Y sperm under zero gravity.
Forces of Patriarchy: Adolescent Experiences of Sexuality and Conceptions of Relationships.
ERIC Educational Resources Information Center
Van Roosmalen, Erica
2000-01-01
Examines the role of patriarchy and capitalism in shaping adolescent girls' experiences of sexuality and conceptions of relationships. Analysis of letters to a teen advice column highlights concerns and issues of sexuality, gender identity, and relationships for adolescent girls. Argues that during early adolescence, the power and contradictions…
Institutional Advancement: A Marketing Perspective. Part I: A Proposal.
ERIC Educational Resources Information Center
Moriarty, Daniel F.
Strategies are proposed for the implementation of the marketing concept at Triton College. The report begins by describing the establishment and goals of the Marketing Task Force and goes on to define "institutional advancement," as a positive, progressive response to community educational needs, and "the marketing concept," as suggesting an…
CHANGING CONCEPTS OF PRODUCTIVE LIVING.
ERIC Educational Resources Information Center
BOYD, ROBERT D.
AT A CONFERENCE OF ADULT EDUCATORS DESIGNED TO BRING INTO FOCUS NEW PERSPECTIVES OF THE ROLES OF ADULT EDUCATION, PAPERS WERE PRESENTED ON THE CHANGING CONCEPTS OF PRODUCTIVE LIVING AND THE RELATIONSHIP BETWEEN CONCERN FOR PRODUCTIVE LIVING AND ADULT EDUCATION. AN OVERVIEW PROVIDED A WORKING ORIENTATION AND DESCRIBED THE BASIC FORCES AND PROBLEMS…
Unified Technical Concepts. Physics for Technicians.
ERIC Educational Resources Information Center
Center for Occupational Research and Development, Inc., Waco, TX.
Unified Technical Concepts (UTC) is a modular system for teaching applied physics in two-year postsecondary programs. This UTC classroom textbook, consisting of 14 chapters, deals with physics for technicians. Addressed in the individual chapters of the guide are the following topics: force, work, rate, momentum, resistance, power, potential and…
International Military Cooperation: From Concepts to Constructs
ERIC Educational Resources Information Center
D'Orazio, Vito
2013-01-01
International cooperation on issues of security is a central concept in many theoretical debates in international relations. This dissertation is an attempt to lay the foundation for measuring military cooperation and understanding the forces brought forth through its expansion. The central notion is that the set of policies related to military…
Magic From the Woods. A Teacher's Handbook for Environmental Education.
ERIC Educational Resources Information Center
Warren, Mark
This workbook contains suggestions for environmental learning adventures for elementary school children in a forest. The activities are classified under various concepts such as sound, growth, adaptation, force, variety, water, habitat, design time, and conservation. The concept is first defined. Then a preparation exercise to get the students…
ERIC Educational Resources Information Center
Cantwell, Brendan
2011-01-01
This article draws upon concepts developed in recent empirical and theoretical work on high skilled and academic mobility and migration including accidental mobility, forced mobility and negotiated mobility. These concepts inform a situated, qualitative study of mobility among international postdoctoral researchers in life sciences and engineering…
[The history of the concept of vital force].
Lohff, B
1981-12-01
This article deals with the term "Lebenskraft - vital force' from the terminological point of view (life vs. force), as well as from the historical one-(1774-1848), also considering the place this term occupies in colloquial speech. This term, however, first introduced into medicine by Kasimir Medicus in 1774, cannot be defined in a philosophical sense. Historically though, it can be proved that four different starting positions have caused the different ways of interpreting this "vital force'. Alongside the physical interpretations, i.e. the impossibility of a perpetuum mobile, there were some reflections on the chemical mode of action (chemical dynamism, J.Chr. Reil). Another aspect developed from the irritability concept (G.R. Treviranus); furthermore a special interpretation resulted from the microcosmos-macrocosmos-analogy (Fr.L. Augustin). Thus these different positions had influenced the investigations carried out in the fields of biochemistry, neuro-physiology and comparative anatomy. Since the investigations of Emil Du Bois-Reymond and his articles on "Lebenskraft' the term and the hypothesis of vital force was no longer of scientific importance. The term lived on in colloquial speech and thus became a characteristic of the difference between a scientific and non scientific approach to life.
A Near-Term, High-Confidence Heavy Lift Launch Vehicle
NASA Technical Reports Server (NTRS)
Rothschild, William J.; Talay, Theodore A.
2009-01-01
The use of well understood, legacy elements of the Space Shuttle system could yield a near-term, high-confidence Heavy Lift Launch Vehicle that offers significant performance, reliability, schedule, risk, cost, and work force transition benefits. A side-mount Shuttle-Derived Vehicle (SDV) concept has been defined that has major improvements over previous Shuttle-C concepts. This SDV is shown to carry crew plus large logistics payloads to the ISS, support an operationally efficient and cost effective program of lunar exploration, and offer the potential to support commercial launch operations. This paper provides the latest data and estimates on the configurations, performance, concept of operations, reliability and safety, development schedule, risks, costs, and work force transition opportunities for this optimized side-mount SDV concept. The results presented in this paper have been based on established models and fully validated analysis tools used by the Space Shuttle Program, and are consistent with similar analysis tools commonly used throughout the aerospace industry. While these results serve as a factual basis for comparisons with other launch system architectures, no such comparisons are presented in this paper. The authors welcome comparisons between this optimized SDV and other Heavy Lift Launch Vehicle concepts.
NASA Astrophysics Data System (ADS)
Kornecki, A.
1983-09-01
This study was motivated by work on the stability of nonconservative elastic systems and flutter of certain fluid-elastic systems. A literature review revealed that the concepts of conservative forces (and systems) and gyroscopic forces (and systems) need clarifications, and the definitions formulated by different authors for the forces and systems are sometimes conflicting. In this report, these controversies are thoroughly discussed and conservative and gyroscopic systems are redefined within the framework of the classical dynamics of a system of particles.
Maintenance Assistance and Instruction Team (MAIT) Concept Review (Project LEAP, Issue 104).
1975-08-20
Reserve Component forces , to include identification of military and civilian authorized spaces, their associated equipment, salary, and travel costs...5) How many MAIT teams are authorized/assigned to each major command by installation (location)? (6) How many NIAIT are in support of Active Forces ... Forces , the USAR and the National Guard? (12) As a minimum, the following alternative courses of action should be considered: (a) Continue the MAIT
Optimizing the US Navy’s Combat Logistics Force
2008-01-01
Optimizing the US Navy’s Combat Logistics Force Gerald G. Brown, W. Matthew Carlyle Operations Research Department, Naval Postgraduate School...Wiley InterScience (www.interscience.wiley.com). Abstract: We study how changes to the composition and employment of the US Navy combat logistic force...evaluate new CLF ship designs, advise what number of ships in a new ship class would be needed, test concepts for forward at-sea logistics bases in lieu
In Order to Win, Learn How to Fight: The US Army in Urban Operations
2002-05-23
Arms MOUT Task Force, “Mission Need Statement For Urban Operations Training Capability.” Annex A, 23 Feb 2001, 5-6. 93 Mr. John Bastone , Combined Arms...John Bastone , Combined Arms MOUT Task Force, Phone interview with author on Feb.5, 2002. 100 “A Concept for Future Military Operations on Urbanized...conduct close quarters combat with enemy forces. For this 108 Mr. John Bastone , Phone Interview, Feb.5
U.S. Special Forces: Culture Warriors
2014-12-01
appropriate. 5 B. THESIS STRUCTURE The thesis proceeds as follows: Chapter II examines the concept of culture by looking at how academia, the business...refer to culture simply as a concept . Sociologist Orlando Patterson notes that “there is strong resistance to attempts to explain any aspect of human...behavior in cultural terms,”8 while anthropologist Alfred L. Kroeber and others explain, “the concept ( culture ) has had a name for less than eighty
Modeling of Steer-by-Wire System Used in New Braking Handwheel Concept
NASA Astrophysics Data System (ADS)
Messaoudène, K.; Oufroukh, N. Ait; Mammar, S.
2008-06-01
The handwheel is one of the primary control mechanisms of automobile thus interaction between the handwheel and the driver is critical to safety. The driver applies forces that direct the vehicle while the handwheel communicates feedback information to the driver of the forces experience by the car within its environment. The handwheel also provides a predictable mechanical feel to the driver to allow smooth and safe control. Many researchers tried to reproduce this feeling by creating steer-by-wire systems. This paper explores this new concept of handwheel and it describes the modeling steps of the components including the restitution mechanism for force feedback and its various links with the vehicle lateral dynamics and the pneumatic contacts. The aim is to explore the possibility to combine a braking device within the steer-by-wire system in order to provide a more suitable and ergonomic device to the driver.
Learning a trajectory using adjoint functions and teacher forcing
NASA Technical Reports Server (NTRS)
Toomarian, Nikzad B.; Barhen, Jacob
1992-01-01
A new methodology for faster supervised temporal learning in nonlinear neural networks is presented which builds upon the concept of adjoint operators to allow fast computation of the gradients of an error functional with respect to all parameters of the neural architecture, and exploits the concept of teacher forcing to incorporate information on the desired output into the activation dynamics. The importance of the initial or final time conditions for the adjoint equations is discussed. A new algorithm is presented in which the adjoint equations are solved simultaneously (i.e., forward in time) with the activation dynamics of the neural network. We also indicate how teacher forcing can be modulated in time as learning proceeds. The results obtained show that the learning time is reduced by one to two orders of magnitude with respect to previously published results, while trajectory tracking is significantly improved. The proposed methodology makes hardware implementation of temporal learning attractive for real-time applications.
Rigorous force field optimization principles based on statistical distance minimization
Vlcek, Lukas; Chialvo, Ariel A.
2015-10-12
We use the concept of statistical distance to define a measure of distinguishability between a pair of statistical mechanical systems, i.e., a model and its target, and show that its minimization leads to general convergence of the model’s static measurable properties to those of the target. Here we exploit this feature to define a rigorous basis for the development of accurate and robust effective molecular force fields that are inherently compatible with coarse-grained experimental data. The new model optimization principles and their efficient implementation are illustrated through selected examples, whose outcome demonstrates the higher robustness and predictive accuracy of themore » approach compared to other currently used methods, such as force matching and relative entropy minimization. We also discuss relations between the newly developed principles and established thermodynamic concepts, which include the Gibbs-Bogoliubov inequality and the thermodynamic length.« less
Analyzing force concept inventory with item response theory
NASA Astrophysics Data System (ADS)
Wang, Jing; Bao, Lei
2010-10-01
Item response theory is a popular assessment method used in education. It rests on the assumption of a probability framework that relates students' innate ability and their performance on test questions. Item response theory transforms students' raw test scores into a scaled proficiency score, which can be used to compare results obtained with different test questions. The scaled score also addresses the issues of ceiling effects and guessing, which commonly exist in quantitative assessment. We used item response theory to analyze the force concept inventory (FCI). Our results show that item response theory can be useful for analyzing physics concept surveys such as the FCI and produces results about the individual questions and student performance that are beyond the capability of classical statistics. The theory yields detailed measurement parameters regarding the difficulty, discrimination features, and probability of correct guess for each of the FCI questions.
NASA Astrophysics Data System (ADS)
Lindvai-Soos, Daniel; Horn, Martin
2018-07-01
In this article a novel vehicle dynamics control concept is designed for a vehicle equipped with wheel individual electric traction machines, electronically controlled brakes and semi-active suspensions. The suspension's cross-couplings between traction forces and vertical forces via anti-dive and anti-squat geometry is utilised in the control concept to improve driving comfort and driving stability. The control concept is divided into one main and two cascaded branches. The main controller consists of a multivariable vehicle dynamics controller and a control allocation scheme to improve the vehicle's driving comfort. The cascaded feedback loops maintain the vehicle's stability according to wheel slip and vehicle sideslip. The performance of the combined vehicle dynamics controller is compared to a standard approach in simulation. It can be stated that the controller piloting semi-active suspensions together with brake and traction devices enables a superior performance regarding comfort and stability.
The roots of gender inequity in technical areas
NASA Astrophysics Data System (ADS)
Campbell, James Reed
This article describes a study of the academic self-concepts, attributions and achievements of male and female Asian American and Caucasian students who won Westinghouse Awards in 1984 and 1985. The results of the study showed that fewer Caucasian female recipients anticipated college majors in the technical areas. Furthermore, this group of females scored lower on both parts of the SAT, scored lower on all of the self-concept scales, and also scored lower on both attribution scales. In contrast, the Asian females optimized courses for the gifted and specialized research courses to distance themselves from the American females in almost all areas. The author linked these ethnic, gender differences to underlying psychological and sociological forces that are responsible for the self-concept and attribution differences. It is these forces that must be altered for Caucasian females to rectify the gender inequalities that exist in the technical areas.
[Understanding mistake-proofing].
de Saint Maurice, G; Giraud, N; Ausset, S; Auroy, Y; Lenoir, B; Amalberti, R
2011-01-01
The mistake-proofing concept often refers to physical devices that prevent actors from making a wrong action. In anaesthesiology, one immediately thinks to specific design of outlets for medical gases. More generally, the principle of mistake-proofing is to avoid an error, by placing knowledge in the world rather than knowledge in the head. As it often happens in risk management, healthcare has received information transfers from the industry. Computer is changing the concept of mistake-proofing, initially based on physical design, such as aerospace and automotive industry. The mistake-proofing concept may be applied to prevention, detection, and mitigation of errors. The forcing functions are a specific part of mistake-proofing: they prevent a wrong action or they force a virtuous one. Grout proposes a little shortcut to identify mistake-proofing devices: "If it is not possible to picture it in action, it is probably not a mistake-proofing device". Copyright © 2010 Elsevier Masson SAS. All rights reserved.
Friction Force: From Mechanics to Thermodynamics
ERIC Educational Resources Information Center
Ferrari, Christian; Gruber, Christian
2010-01-01
We study some mechanical problems in which a friction force is acting on a system. Using the fundamental concepts of state, time evolution and energy conservation, we explain how to extend Newtonian mechanics to thermodynamics. We arrive at the two laws of thermodynamics and then apply them to investigate the time evolution and heat transfer of…
A simple derivation of Lorentz self-force
NASA Astrophysics Data System (ADS)
Haque, Asrarul
2014-09-01
We derive the Lorentz self-force for a charged particle in arbitrary non-relativistic motion by averaging the retarded fields. The derivation is simple and at the same time pedagogically accessible. We obtain the radiation reaction for a charged particle moving in a circle. We pin down the underlying concept of mass renormalization.
Theory of Aircraft Flight. Aerospace Education II.
ERIC Educational Resources Information Center
Elmer, James D.
This revised textbook, one in the Aerospace Education II series, provides answers to many questions related to airplanes and properties of air flight. The first chapter provides a description of aerodynamic forces and deals with concepts such as acceleration, velocity, and forces of flight. The second chapter is devoted to the discussion of…
Exploring the Gender Gap in the Conceptual Survey of Electricity and Magnetism
ERIC Educational Resources Information Center
Henderson, Rachel; Stewart, Gay; Stewart, John; Michaluk, Lynnette; Traxler, Adrienne
2017-01-01
The "gender gap" on various physics conceptual evaluations has been extensively studied. Men's average pretest scores on the Force Concept Inventory and Force and Motion Conceptual Evaluation are 13% higher than women's, and post-test scores are on average 12% higher than women's. This study analyzed the gender differences within the…
Governance Paradigms of Public Universities: An International Comparative Study
ERIC Educational Resources Information Center
Christopher, Joe
2012-01-01
This study aims to develop a conceptual model of the wider influencing forces impacting the governance paradigms of public universities. It draws on the multi-theoretical governance concept and seeks to identify these forces through the lens of chief audit executives using a qualitative research approach. The interview data supported by published…
African-American Soul Force: Dance, Music and Vera Mae Green.
ERIC Educational Resources Information Center
Bolles, A. Lynn
1986-01-01
The Black anthropologist, Vera Mae Green, is featured in this analysis of the concept of soul as applied to African-Americans. Music and dance are used to express soul in cultural context. But soul is also a force, an energy which encompasses the Black experience and makes Black culture persevere. (VM)
A Microeconomic Approach to the Issue of Quality in the Teaching Force.
ERIC Educational Resources Information Center
Kim, Hye-Sook
This study approaches the issue of quality in the teaching force using a microeconomic framework that applies the concept of "opportunity cost." As teaching is a low-paid profession, accepting a teaching position may be associated with high opportunity costs (foregone benefits) for more academically talented college students because they could…
ERIC Educational Resources Information Center
Argaw, Aweke Shishigu
2015-01-01
Foundations are the forces that influence the minds of curriculum developers, which affect the content and structure of the curriculum. These forces are beliefs and orientations as well as conceptions of learning and the needs of society. Foundation of curriculum is rooted with the foundation of education. Historically, modern curriculum and…
ERIC Educational Resources Information Center
Perrin, Graham
2012-01-01
When providing training to teachers struggling with the concept of forces, the author encourages them to start with something within the experience of the children they are teaching. For example, show them photographs taken on windy days, such as that of a tree, and ask them to explain what is happening. This encourages the children to focus on…
Project Physics Tests 2, Motion in the Heavens.
ERIC Educational Resources Information Center
Harvard Univ., Cambridge, MA. Harvard Project Physics.
Test items relating to Project Physics Unit 2 are presented in this booklet. Included are 70 multiple-choice and 22 problem-and-essay questions. Concepts of motion in the heavens are examined for planetary motions, heliocentric theory, forces exerted on the planets, Kepler's laws, gravitational force, Galileo's work, satellite orbits, Jupiter's…
Project Physics Reader 1, Concepts of Motion.
ERIC Educational Resources Information Center
Harvard Univ., Cambridge, MA. Harvard Project Physics.
As a supplement to Project Physics Unit 1, 21 articles are presented in this reader. Concepts of motion are discussed under headings: motion, motion in words, representation of movement, introducing vectors, Galileo's discussion of projectile motion, Newton's laws of dynamics, the dynamics of a golf club, report on Tait's lecture on force, and bad…
Learning about Life and Death in Early Childhood
ERIC Educational Resources Information Center
Slaughter, Virginia; Lyons, Michelle
2003-01-01
Inagaki and Hatano (2002) have argued that young children initially understand biological phenomena in terms of vitalism, a mode of construal in which "life" or "life-force" is the central causal-explanatory concept. This study investigated the development of vitalistic reasoning in young children's concepts of life, the human body and death.…
Adolescent Self-Concept among Chinese, Kazakh, American and American Indians.
ERIC Educational Resources Information Center
Sharpes, Donald K.
Neuroscientific evidence for the underlying neuronal activity in the cerebral cortex for psychological states points to the need for an alternative physiological hypothesis for the construct of self concept. Evidence from neuroscience and hereditability studies leads to the conclusion that genetic forces may be clearly at work in the perception of…
Drivers, Start Your Glue Guns: Using Model Stock Cars to Explore Motion and Force Concepts
ERIC Educational Resources Information Center
Angle, Julie
2011-01-01
The recently released document "A Framework for K-12 Science Education: Practices, Crosscutting Concepts, and Core Ideas" emphasizes the importance of engaging students in practices of science and engineering to help them understand how scientific knowledge about the natural world develops. The document identifies eight essential…
"Aesthetic Emotion": An Ambiguous Concept in John Dewey's Aesthetics
ERIC Educational Resources Information Center
Hohr, H.
2010-01-01
This article analyses the concept of "aesthetic emotion" in John Dewey's "Art as experience". The analysis shows that Dewey's line of investigation offers valuable insights as to the role of emotion in experience: it shows emotion as an integral part and structuring force, as a cultural and historical category. However, the notion of aesthetic…
Teaching the Concept of Resonance with the Help of a Classical Guitar
ERIC Educational Resources Information Center
Kasar, M. Kaan; Yurumezoglu, Kemal; Sengoren, Serap Kaya
2012-01-01
Resonance refers to the vibrations of larger amplitude that are produced under the effect of a harmonic driving force. Although resonance is an essential concept behind many events happening in nature, students usually have difficulty in learning and explaining the phenomenon. Various demonstrations are carried out in physics classes to clarify…
A concept of active mount for space applications
NASA Astrophysics Data System (ADS)
Souleille, A.; Lampert, T.; Lafarga, V.; Hellegouarch, S.; Rondineau, A.; Rodrigues, G.; Collette, C.
2018-06-01
Sensitive payloads mounted on top of launchers are subjected to many sources of disturbances during the flight. The most severe dynamic loads arise from the ignition of the motors, gusts, pressure fluctuations in the booster and from the separation of the boosters. The transmission of these dynamic forces can be reduced by mounting payloads on passive isolators, which comes at the expense of harmful amplifications of the motion at low frequency due to suspension resonances. To bypass this shortcoming, this paper presents a novel concept of active mount for aerospace payloads, which is easy to install, and meets two objectives. The first one is a high damping authority on both suspension resonances and flexible resonances without compromising the isolation and large stability margins of the closed loop system due to the collocation of the actuator and the sensor. The second one is a broadband reduction of the dynamic force transmitted to the payload, which was achieved in terms of 16 dB. The concept is presented in the first part of the paper and studied numerically and experimentally on a single degree of freedom isolator. A commercial isolator has been chosen for the purpose of the demonstration. The second part of the paper is dedicated to experimental validations on multi-degree of freedom scaled test benches. It is shown that the force feedback allows damping of both suspension and flexible modes (first and second modes, respectively), and significantly reducing the force transmitted in some broad frequency ranges.
2015-06-01
between military officers and the rest of society. Sociologist Morris Janowitz argued for a constabulary concept to adapt the military profession to...the Military Establishment,” 100-122. 23 Morris Janowitz, The Professional Soldier: A Social and Political Portrait (New York: Free Press, 1960...Transaction Publishers, 1962), 188-189. Morris Janowitz and Charles C. Moskos, “Five Years of the All- Volunteer Force: 1973-1978” Armed Forces and Society
2010-09-01
application of existing assessment tools that may be applicable to Marine Air Ground Task Force (MAGTF) Command, Control, Communications and...of existing assessment tools that may be applicable to Marine Air Ground Task Force (MAGTF) Command, Control, Communications and Computers (C4...assessment tools and analysis concepts that may be extended to the Marine Corps’ C4 System of Systems assessment methodology as a means to obtain a
2013-04-20
interest, and the country’s archipelagic landscape, there is no capability more functional and indispensable to the AFP than the full spectrum of...military operations other than war. 6 Considering the strategic environment, maritime interest, and its archipelagic landscape, there is no... doctrines . Massive firepower and superior leadership remained the centerpieces of US forces that checked the North Koreans. On the other hand, the
Zhang, Xiaowei; Zhou, Qing
2016-01-01
This study investigated overall performance of an energy-absorbing sliding seat concept for whiplash neck injury prevention. The sliding seat allows its seat pan to slide backward for some distance under certain restraint force to absorb crash energy in rear impacts. A numerical model that consisted of vehicle interior, seat, seat belt, and BioRID II dummy was built in MADYMO to evaluate whiplash neck injury in rear impact. A parametric study of the effects of sliding seat parameters, including position and cushion stiffness of head restraint, seatback cushion stiffness, recliner characteristics, and especially sliding energy-absorbing (EA) restraint force, on neck injury criteria was conducted in order to compare the effectiveness of the sliding seat concept with that of other existing anti-whiplash mechanisms. Optimal sliding seat design configurations in rear crashes of different severities were obtained. A sliding seat prototype with bending of a steel strip as an EA mechanism was fabricated and tested in a sled test environment to validate the concept. The performance of the sliding seat under frontal and rollover impacts was checked to make sure the sliding mechanism did not result in any negative effects. The protective effect of the sliding seat with EA restraint force is comparable to that of head restraint-based and recliner stiffness-based anti-whiplash mechanisms. EA restraint force levels of 3 kN in rear impacts of low and medium severities and 6 kN in impacts of high severity were obtained from optimization. In frontal collision and rollover, compared to the nonsliding seat, the sliding seat does not result in any negative effects on occupant protection. The sled test results of the sliding seat prototype have shown the effectiveness of the concept for reducing neck injury risks. As a countermeasure, the sliding seat with appropriate restraint forces can significantly reduce whiplash neck injury risk in rear impacts of low, medium, and high severities with no negative effects on other crash load cases.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Peter H. Titus and Ali Zolfaghari
A critical design feature of any tokamak is the space taken up by the inner leg of the toroidal field (TF) coil. The radial build needed for the TF inner leg, along with shield thickness , size of the central solenoid and plasma minor radius set the major radius of the machine. The cost of the tokamak core roughly scales with the cube of the major radius. Small reductions in the TF build can have a big impact on the overall cost of the reactor. The cross section of the TF inner leg must structurally support the centering force andmore » that portion of the vertical separating force that is not supported by the outer structures. In this paper, the TF inner leg equatorial plane cross sections are considered. Out-of- Plane (OOP) forces must also be supported, but these are largest away from the equatorial plane, in the inner upper and lower corners and outboard sections of the TF coil. OOP forces are taken by structures that are not closely coupled with the radial build of the central column at the equatorial plane. The "Vertical Access AT Pilot Plant" currently under consideration at PPPL is used as a starting point for the structural, field and current requirements. Other TF structural concepts are considered. Most are drawn from existing designs such as ITER's circular conduits in radial plates bearing on a heavy nose section, and TPX's square conduits in a case, Each of these concepts can rely on full wedging, or partial wedging. Vaulted TF coils are considered as are those with some component of bucking against a central solenoid or bucking post. With the expectation that the pilot plant will be a steady state machine, a static stress criteria is used for all the concepts. The coils are assumed to be superconducting, with the superconductor not contributing to the structural strength. Limit analysis is employed to assess the degree of conservatism in the static criteria as it is applied to a linear elastic stress analysis. TF concepts, and in particular the PPPL AT PILOT plate concept are evaluated based on amount of space needed for structure and the amount of space left for superconductor.« less
Linear separability in superordinate natural language concepts.
Ruts, Wim; Storms, Gert; Hampton, James
2004-01-01
Two experiments are reported in which linear separability was investigated in superordinate natural language concept pairs (e.g., toiletry-sewing gear). Representations of the exemplars of semantically related concept pairs were derived in two to five dimensions using multidimensional scaling (MDS) of similarities based on possession of the concept features. Next, category membership, obtained from an exemplar generation study (in Experiment 1) and from a forced-choice classification task (in Experiment 2) was predicted from the coordinates of the MDS representation using log linear analysis. The results showed that all natural kind concept pairs were perfectly linearly separable, whereas artifact concept pairs showed several violations. Clear linear separability of natural language concept pairs is in line with independent cue models. The violations in the artifact pairs, however, yield clear evidence against the independent cue models.
Haptic control with environment force estimation for telesurgery.
Bhattacharjee, Tapomayukh; Son, Hyoung Il; Lee, Doo Yong
2008-01-01
Success of telesurgical operations depends on better position tracking ability of the slave device. Improved position tracking of the slave device can lead to safer and less strenuous telesurgical operations. The two-channel force-position control architecture is widely used for better position tracking ability. This architecture requires force sensors for direct force feedback. Force sensors may not be a good choice in the telesurgical environment because of the inherent noise, and limitation in the deployable place and space. Hence, environment force estimation is developed using the concept of the robot function parameter matrix and a recursive least squares method. Simulation results show efficacy of the proposed method. The slave device successfully tracks the position of the master device, and the estimation error quickly becomes negligible.
Interpreting Power-Force-Velocity Profiles for Individualized and Specific Training.
Morin, Jean-Benoît; Samozino, Pierre
2016-03-01
Recent studies have brought new insights into the evaluation of power-force-velocity profiles in both ballistic push-offs (eg, jumps) and sprint movements. These are major physical components of performance in many sports, and the methods the authors developed and validated are based on data that are now rather simple to obtain in field conditions (eg, body mass, jump height, sprint times, or velocity). The promising aspect of these approaches is that they allow for more individualized and accurate evaluation, monitoring, and training practices, the success of which is highly dependent on the correct collection, generation, and interpretation of athletes' mechanical outputs. The authors therefore wanted to provide a practical vade mecum to sports practitioners interested in implementing these power-force-velocity-profiling approaches. After providing a summary of theoretical and practical definitions for the main variables, the authors first detail how vertical profiling can be used to manage ballistic push-off performance, with emphasis on the concept of optimal force-velocity profile and the associated force-velocity imbalance. Furthermore, they discuss these same concepts with regard to horizontal profiling in the management of sprinting performance. These sections are illustrated by typical examples from the authors' practice. Finally, they provide a practical and operational synthesis and outline future challenges that will help further develop these approaches.
Formative Assessment Probes: Pushes and Pulls
ERIC Educational Resources Information Center
Keeley, Page
2011-01-01
When the concept of force is first taught in the elementary curriculum, it is usually introduced as a push or a pull. The recently released "A Framework for K-12 Science Education" describes grade band endpoints for the Core Idea: Motion and Stability: Forces and Interactions (NRC 2011). It states that by the end of grade 2 students should know…
Choosing a Hand-Held Inventory Device
ERIC Educational Resources Information Center
Green, Lois; Hughes, Janet; Neff, Verne; Notartomas, Trish
2008-01-01
In spring of 2006, a task force was charged to look at the feasibility of acquiring hand-held inventory devices for the Pennsylvania State University Libraries (PSUL). The task force's charge was not to look at the whole concept of doing an inventory, but rather to focus on the feasibility of acquiring hand-held devices to use in an inventory.…
ERIC Educational Resources Information Center
Timur, Serkan
2012-01-01
The purpose of this study is to identify the cognitive structures of prospective preschool teachers concerning the concepts included in the subject "force and motion". The study was conducted on a total of 56 prospective teachers who studied Preschool Teaching at Canakkale Onsekiz Mart University. The Word Association Test (WAT) was…
Oscillations of a Meterstick on Two Rotating Shafts
ERIC Educational Resources Information Center
Balta, Nuri
2016-01-01
Most students find real-world examples of harmonic oscillations interesting. Besides, normal and friction forces are the types of concepts in physics that are readily applicable to their everyday life. For instance, we depend on these forces to write, to drive cars, to pick up objects, and even to walk! And yet introductory physics students have…
A Hands-On Activity to Build Mastery of Intermolecular Forces and Its Impacts on Student Learning
ERIC Educational Resources Information Center
Bruck, Laura B.
2016-01-01
The intermolecular forces activity presented in this article is designed to foster concept-building through students' use of concrete, manipulative objects, and it was developed to be pedagogically sound. Data analysis via pre- and posttesting and subsequent exam questions indicated that students who had the opportunity to participate in the…
ERIC Educational Resources Information Center
Sendur, Gulten
2014-01-01
The aim of this study is to determine prospective chemistry teachers' creative comparisons about the basic concepts of inter- and intramolecular forces, and to uncover the relationship between these creative comparisons and prospective teachers' conceptual understanding. Based on a phenomenological research method, this study was conducted with…
ERIC Educational Resources Information Center
2000
Walking on a balance beam or riding a bike both require motion and balance. This program will reveal how unbalanced forces create motion, while balanced forces keep things still. Students also learn how concepts like velocity, acceleration, and momentum fit into this puzzle. A unique hands-on activity combined with vivid imagery and graphics…
ERIC Educational Resources Information Center
Jimenez-Valladares, Juan de Dios; Perales-Palacios, F. Javier
2001-01-01
When students are forming their ideas of what will eventually become the concept of force, the images of arrows in our standard diagrams carry with them unconscious attributes of direction of movement and so on. Describes how the use of a 'symbolic representation of interactions' with double-headed arrows avoids these unwanted messages being…
Dramatic (and Simple!) Demonstration of Newton's Third Law
ERIC Educational Resources Information Center
Feldman, Gerald
2011-01-01
An operational understanding of Newton's third law is often elusive for students. Typical examples of this concept are given for contact forces that are closer to the students' everyday experience. While this is a good thing in general, the reaction force can sometimes be taken for granted, and the students can miss the opportunity to really think…
Child Marriage or Forced Marriage? South Asian Communities in North East England
ERIC Educational Resources Information Center
Gangoli, Geetanjali; McCarry, Melanie; Razak, Amina
2009-01-01
This article addresses the links between child marriage and forced marriage in the UK, drawing from a research study on South Asian communities in North East England. It looks at definitional issues through an analysis of UK and South Asian policies. It also analyses how these concepts are understood by service providers, survivors of child…
Focusing on Concepts by Covering Them Simultaneously
NASA Astrophysics Data System (ADS)
Schwartz, Pete
2017-05-01
"Parallel" pedagogy covers the four mechanics concepts of momentum, energy, forces, and kinematics simultaneously instead of building each concept on an understanding of the previous one. Course content is delivered through interactive videos, allowing class time for group work and student-centered activities. We start with simple examples, building complexity throughout the course with the introduction of springs, two dimensions, vectors, energy diagrams, universal gravitation, and rotation. Success means that students ponder underlying physics concepts rather than hunt for formulas. Surveys indicate that students accept this learning model well and have considerable improvement in applied conceptual understanding.
[The theory of postmortem rigidity: the history and an original concept].
Kil'diushov, E M; Tumanov, É V; Sokolova, Z Iu
2012-01-01
The original theory of postmortem rigidity has been developed and substantiated based on the concept of postmortem muscular contracture. It is postulated that the unrestricted growth of Ca2+ concentration in myoplasm of contractile cells during the immediate postmortal period brings the actin-myosine complex to the force generation state without subsequent relaxation.
Conventional Prompt Global Strike and Long-Range Ballistic Missiles: Background and Issues
2011-04-21
winglets , rather than on the winged design of the HTV-2. Upon nearing a target, the weapon would be able to maneuver to avoid flying over third party...concept from PGS, Congress, initially at least, blended both into the request for a new report. The Air Force submitted its report on the CAV concept of
On the Concept of Energy: Eclecticism and Rationality
ERIC Educational Resources Information Center
Coelho, Ricardo Lopes
2014-01-01
In the theory of heat of the first half of the nineteenth century, heat was a substance. Mayer and Joule contradicted this thesis but developed different concepts of heat. Heat was a force for Mayer and a motion for Joule. Both Mayer and Joule determined the mechanical equivalent of heat. This result was, however, justified in accordance with…
New "persona" concept helps site designers cater to target user segments' needs.
2004-09-01
Using the relatively new "persona" design concept, Web strategists create a set of archetypical user characters, each one representing one of their site's primary audiences. Then, as their site is constructed or upgraded, they champion the personas, arguing on their behalf and forcing the design team to take each audience's needs and wants into account.
Handbook of Supersonic Aerodynamics Volume 1
1950-04-01
Appears in Z10 Publication Remarks •Mlc) *(lc) •Pile) Angle Potential function Helical angle of advance (propellers) Dimensionless Dependent on...heat of- combustion re(lc) N (cap) Nu. o(lc) Net Nozzle Normal (perpendicu- lar to longitudinal axis) ; normal (force) Nusselt ...Concepts ^ Concept Absolute Acceleration, angular Acceleration due to gravity Added; additional Adiabatic Adiabatic wall Advance, helical angle
Locating the Center of Gravity: The Dance of Normal and Frictional Forces
ERIC Educational Resources Information Center
Balta, Nuri
2012-01-01
Teaching physics concepts with the basic materials that are around us is one of the beauties of physics. Without expensive lab materials and long experiments, many physics concepts can be taught to students using simple tools. Demonstrations with these tools can be presented as discrepant events that surprise, amaze, or puzzle students. Greenslade…
Econo-Physics Models & Metaphors
NASA Astrophysics Data System (ADS)
Jackson, Peter M.
"There is really nothing more pathetic than to have an economist or a retired engineer try to force analogies between the concepts of physics and the concepts of engineers. How many dreary papers have I had to referee in which the author is looking for something that corresponds to entropy or to one or another form of energy?" (Samuelson, 1972, p.254).
Wiimote Experiments: 3-D Inclined Plane Problem for Reinforcing the Vector Concept
ERIC Educational Resources Information Center
Kawam, Alae; Kouh, Minjoon
2011-01-01
In an introductory physics course where students first learn about vectors, they oftentimes struggle with the concept of vector addition and decomposition. For example, the classic physics problem involving a mass on an inclined plane requires the decomposition of the force of gravity into two directions that are parallel and perpendicular to the…
Quantum state atomic force microscopy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Passian, Ali; Siopsis, George
New classical modalities of atomic force microscopy continue to emerge to achieve higher spatial, spectral, and temporal resolution for nanometrology of materials. Here, we introduce the concept of a quantum mechanical modality that capitalizes on squeezed states of probe displacement. We show that such squeezing is enabled nanomechanically when the probe enters the van der Waals regime of interaction with a sample. The effect is studied in the non-contact mode, where we consider the parameter domains characterizing the attractive regime of the probe-sample interaction force.
Logistics Implications of Composite Wings
1993-12-01
Composite Wing and Air Logistics Center Locations 33 12 F-15E Strike Eagle Aircraft 34 la F-16C Fighting Falcon Aircraft 35 14 E-3 Sentry...Structure , 12 2 366th Wing Maintenance Concept 41 vOt Foreword The US Air Force has taken the initiative to reorganize into objective wings, at...the Air Force in 1967. He began his Air Force career as an F-102 radar weapon system specialist and worked on the flight line at Ramstein Air Base
Quantum state atomic force microscopy
Passian, Ali; Siopsis, George
2017-04-10
New classical modalities of atomic force microscopy continue to emerge to achieve higher spatial, spectral, and temporal resolution for nanometrology of materials. Here, we introduce the concept of a quantum mechanical modality that capitalizes on squeezed states of probe displacement. We show that such squeezing is enabled nanomechanically when the probe enters the van der Waals regime of interaction with a sample. The effect is studied in the non-contact mode, where we consider the parameter domains characterizing the attractive regime of the probe-sample interaction force.
1996-10-01
systems currently headed for deployment ( BIDS is highlighted in the chart) to widely dispersed microsensors on micro, autonomous platforms. Small room... Small , Rapidly Deployable Forces" Joe Polito, Dan Rondeau, Sandia National Laboratory V.2. "Robotic Concepts for Small Rapidly Deployable Forces" V-7...Robert Palmquist, Jill Fahrenholtz, Richard Wheeler, Sandia National Laboratory V.3. "Potential for Distributed Ground Sensors in Support of Small Unit V
ERIC Educational Resources Information Center
National Univ. Extension Association, Washington, DC.
In 1968, a national planning conference, under the joint sponsorship of 34 organizations responsing to continuing education needs, created the National Task Force to determine the feasibility of a uniform unit of measurement and develop a proposal for field testing the concept. Stressing that continuing education units should supplement, not…
Inquiry style interactive virtual experiments: a case on circular motion
NASA Astrophysics Data System (ADS)
Zhou, Shaona; Han, Jing; Pelz, Nathaniel; Wang, Xiaojun; Peng, Liangyu; Xiao, Hua; Bao, Lei
2011-11-01
Interest in computer-based learning, especially in the use of virtual reality simulations is increasing rapidly. While there are good reasons to believe that technologies have the potential to improve teaching and learning, how to utilize the technology effectively in teaching specific content difficulties is challenging. To help students develop robust understandings of correct physics concepts, we have developed interactive virtual experiment simulations that have the unique feature of enabling students to experience force and motion via an analogue joystick, allowing them to feel the applied force and simultaneously see its effects. The simulations provide students learning experiences that integrate both scientific representations and low-level sensory cues such as haptic cues under a single setting. In this paper, we introduce a virtual experiment module on circular motion. A controlled study has been conducted to evaluate the impact of using this virtual experiment on students' learning of force and motion in the context of circular motion. The results show that the interactive virtual experiment method is preferred by students and is more effective in helping students grasp the physics concepts than the traditional education method such as problem-solving practices. Our research suggests that well-developed interactive virtual experiments can be useful tools in teaching difficult concepts in science.
Dissipation effects in mechanics and thermodynamics
NASA Astrophysics Data System (ADS)
Güémez, J.; Fiolhais, M.
2016-07-01
With the discussion of three examples, we aim at clarifying the concept of energy transfer associated with dissipation in mechanics and in thermodynamics. The dissipation effects due to dissipative forces, such as the friction force between solids or the drag force in motions in fluids, lead to an internal energy increase of the system and/or to heat transfer to the surroundings. This heat flow is consistent with the second law, which states that the entropy of the universe should increase when those forces are present because of the irreversibility always associated with their actions. As far as mechanics is concerned, the effects of the dissipative forces are included in Newton’s equations as impulses and pseudo-works.
Force level EW in the Australian Defence Force
NASA Astrophysics Data System (ADS)
Finn, Anthony; Chalmers, Greg; Pincombe, Adrian
2001-08-01
The Australian Defence Force is a small force, dependent upon a few high value assets that act as force multipliers. Consequently, it cannot afford to sustain high attrition. The current Concept of Operations for these platforms is to operate them outside the threat envelope. Organic sensors and data links are used to maintain Situational Awareness, Combat Air Patrol is used to intercept hostile missile launch platforms, and Electronic Warfare self-protection is used as a last resort. Unfortunately, it is common for such high value assets to be slowly, non-stealthy, low agility, physically large platforms that follow predictable trajectories. Consequently, they are easy to target and track from a long range and have a high `sitting duck' factor.
Selective structural source identification
NASA Astrophysics Data System (ADS)
Totaro, Nicolas
2018-04-01
In the field of acoustic source reconstruction, the inverse Patch Transfer Function (iPTF) has been recently proposed and has shown satisfactory results whatever the shape of the vibrating surface and whatever the acoustic environment. These two interesting features are due to the virtual acoustic volume concept underlying the iPTF methods. The aim of the present article is to show how this concept of virtual subsystem can be used in structures to reconstruct the applied force distribution. Some virtual boundary conditions can be applied on a part of the structure, called virtual testing structure, to identify the force distribution applied in that zone regardless of the presence of other sources outside the zone under consideration. In the present article, the applicability of the method is only demonstrated on planar structures. However, the final example show how the method can be applied to a complex shape planar structure with point welded stiffeners even in the tested zone. In that case, if the virtual testing structure includes the stiffeners the identified force distribution only exhibits the positions of external applied forces. If the virtual testing structure does not include the stiffeners, the identified force distribution permits to localize the forces due to the coupling between the structure and the stiffeners through the welded points as well as the ones due to the external forces. This is why this approach is considered here as a selective structural source identification method. It is demonstrated that this approach clearly falls in the same framework as the Force Analysis Technique, the Virtual Fields Method or the 2D spatial Fourier transform. Even if this approach has a lot in common with these latters, it has some interesting particularities like its low sensitivity to measurement noise.
Woody, Michael S; Capitanio, Marco; Ostap, E Michael; Goldman, Yale E
2018-04-30
We characterized experimental artifacts arising from the non-linear response of acousto-optical deflectors (AODs) in an ultra-fast force-clamp optical trap and have shown that using electro-optical deflectors (EODs) instead eliminates these artifacts. We give an example of the effects of these artifacts in our ultra-fast force clamp studies of the interaction of myosin with actin filaments. The experimental setup, based on the concept of Capitanio et al. [Nat. Methods 9, 1013-1019 (2012)] utilizes a bead-actin-bead dumbbell held in two force-clamped optical traps which apply a load to the dumbbell to move it at a constant velocity. When myosin binds to actin, the filament motion stops quickly as the total force from the optical traps is transferred to the actomyosin attachment. We found that in our setup, AODs were unsuitable for beam steering due to non-linear variations in beam intensity and deflection angle as a function of driving frequency, likely caused by low-amplitude standing acoustic waves in the deflectors. These aberrations caused instability in the force feedback loops leading to artifactual jumps in the trap position. We demonstrate that beam steering with EODs improves the performance of our instrument. Combining the superior beam-steering capability of the EODs, force acquisition via back-focal-plane interferometry, and dual high-speed FPGA-based feedback loops, we apply precise and constant loads to study the dynamics of interactions between actin and myosin. The same concept applies to studies of other biomolecular interactions.
General purpose force doctrine
DOE Office of Scientific and Technical Information (OSTI.GOV)
Weltman, J.J.
In contemporary American strategic parlance, the general purpose forces have come to mean those forces intended for conflict situations other than nuclear war with the Soviet Union. As with all military forces, the general purpose forces are powerfully determined by prevailing conceptions of the problems they must meet and by institutional biases as to the proper way to deal with those problems. This paper deals with the strategic problems these forces are intended to meet, the various and often conflicting doctrines and organizational structures which have been generated in order to meet those problems, and the factors which will influencemore » general purpose doctrine and structure in the future. This paper does not attempt to prescribe technological solutions to the needs of the general purpose forces. Rather, it attempts to display the doctrinal and institutional context within which new technologies must operate, and which will largely determine whether these technologies are accepted into the force structure or not.« less
Students' proficiency scores within multitrait item response theory
NASA Astrophysics Data System (ADS)
Scott, Terry F.; Schumayer, Daniel
2015-12-01
In this paper we present a series of item response models of data collected using the Force Concept Inventory. The Force Concept Inventory (FCI) was designed to poll the Newtonian conception of force viewed as a multidimensional concept, that is, as a complex of distinguishable conceptual dimensions. Several previous studies have developed single-trait item response models of FCI data; however, we feel that multidimensional models are also appropriate given the explicitly multidimensional design of the inventory. The models employed in the research reported here vary in both the number of fitting parameters and the number of underlying latent traits assumed. We calculate several model information statistics to ensure adequate model fit and to determine which of the models provides the optimal balance of information and parsimony. Our analysis indicates that all item response models tested, from the single-trait Rasch model through to a model with ten latent traits, satisfy the standard requirements of fit. However, analysis of model information criteria indicates that the five-trait model is optimal. We note that an earlier factor analysis of the same FCI data also led to a five-factor model. Furthermore the factors in our previous study and the traits identified in the current work match each other well. The optimal five-trait model assigns proficiency scores to all respondents for each of the five traits. We construct a correlation matrix between the proficiencies in each of these traits. This correlation matrix shows strong correlations between some proficiencies, and strong anticorrelations between others. We present an interpretation of this correlation matrix.
Clinging to the Past: The Air Force’s War on Dual-Career Families
2014-06-01
combines existing research on stress and work-family conflict with new primary research on current USAF dual-career families in the form of a case...incompatibilities between the Air Force family schema (conceptions of, and practices relating to, USAF families). The study combines existing research on stress ... Stress Pathways ..................................................... 74 Figure 5, Civilian Dual-Career Stress Pathways
Introducing Mechanics by Tapping Core Causal Knowledge
ERIC Educational Resources Information Center
Klaassen, Kees; Westra, Axel; Emmett, Katrina; Eijkelhof, Harrie; Lijnse, Piet
2008-01-01
This article concerns an outline of an introductory mechanics course. It is based on the argument that various uses of the concept of force (e.g. from Kepler, Newton and everyday life) share an explanatory strategy based on core causal knowledge. The strategy consists of (a) the idea that a force causes a deviation from how an object would move of…
Constance A. Harrington; Peter J. Gould
2015-01-01
Many temperate and boreal tree species have a chilling requirement, that is, they need to experience cold temperatures during fall and winter to burst bud normally in the spring. Results from trials with 11 Pacific Northwest tree species are consistent with the concept that plants can accumulate both chilling and forcing units simultaneously during the dormant season...
Acceleration of objects to high velocity by electromagnetic forces
Post, Richard F
2017-02-28
Two exemplary approaches to the acceleration of projectiles are provided. Both approaches can utilize concepts associated with the Inductrack maglev system. Either of them provides an effective means of accelerating multi-kilogram projectiles to velocities of several kilometers per second, using launchers of order 10 meters in length, thus enabling the acceleration of projectiles to high velocities by electromagnetic forces.
Enabling Theater Security Cooperation Through Regionally Aligned Forces
2013-03-01
combatant commanders in successfully implementing this initiative, the Service and the Department of Defense will have to overcome several significant...commanders in successfully implementing this initiative, the Service and the Department of Defense will have to overcome several significant challenges...combatant commands, but several significant challenges must be overcome for the RAF to become a viable force employment concept. Analyzing the Army’s
ERIC Educational Resources Information Center
Rincke, Karsten
2011-01-01
Although a broad literature exists concerning the development of conceptual understanding of force and other topics within mechanics, little is known about the role and development of students' talk about the subject. The paper presents an in-depth investigation of students' talk whilst being introduced to the concept of force. The main research…
1961-01-01
A Dyna-Soar (Dynamic Soaring) vehicle clears the launch tower atop an Air Force Titan II launch vehicle in this 1961 artist's concept. Originally conceived by the U.S. Air Force in 1957 as a marned, rocket-propelled glider in a delta-winged configuration, the Dyna-Soar was considered by Marshall Space Flight Center planners as an upper stage for the Saturn C-2 launch vehicle.
ERIC Educational Resources Information Center
Ishimoto, Michi; Thornton, Ronald K.; Sokoloff, David R.
2014-01-01
This study assesses the Japanese translation of the Force and Motion Conceptual Evaluation (FMCE). Researchers are often interested in comparing the conceptual ideas of students with different cultural backgrounds. The FMCE has been useful in identifying the concepts of English-speaking students from different backgrounds. To identify effectively…
2008-12-01
time- on-task in deploying a patrol force, for example. In its most basic form, an FOB consists of a ring of barbed wire around a position with a...Modernizing The Marine Corps’ CH- 53 Super Stallion Helicopter,” Thesis, NPS (December 2001). HIGH LEVEL OF IMPORTANCE LOW 62 TASKS
1988-11-01
as part of the required training for Army contracting personnel. Specifically, these were courses in contract administration and contract law offered...courts and boards. The process itself was discussed in very general terms.[7] The AFIT Government Contract Law Course concerns itself with legal concepts...Washington, D.C., 1984 4. . Air Force Institute of Technology, Government Contract Law , Course Manual, Wright-Patterson Air Force Base, Ohio, April
Colombian Strategies and Operational Concepts Used in Today’s Counterterrorism Warfare
2009-06-12
production and trafficking worldwide. Colombian President, Alvaro Uribe Velez, the military and police forces have been implementing strategies and...with drug production and trafficking worldwide. Together Colombian President, Alvaro Uribe Velez, the military and the police forces have been...and techniques throughout the years. Today, leveraging President Alvaro Uribe Velez’s strategic vision coupled with improved operational capabilities
ERIC Educational Resources Information Center
Debons, Anthony; and Others
A proposed classification system was studied to determine its efficacy to the Air Force Control-Display Area. Based on negative outcomes from a logical assessment of the proposed system, an alternate system was proposed to include the coordinate index concept. Upon development of a thesaurus and an index system for 106 documents on VSTOL/VTOL…
School and community relations in North America: Creative tensions
NASA Astrophysics Data System (ADS)
Loughran, E.; Reed, H. B.
1980-09-01
School and community relations in North America reflect creative tensions between the conserving forces of schooling and the changing forces of community. During crisis periods community development needs may modify the school's focus on individual learner growth, but generally schools use the community to extend and enrich the traditional modes. School and community interactions are chiefly characterized by such settings as community schools, community education, adult education, home and school (PTA) associations, work-study programs, curriculum-community resource programs. Recent social forces are creating heightened tensions: cultural pluralism, reduced resources, Third World influences, international conflicts, personal alienation, population concerns, energy problems, community power issues. These forces are gradually shifting school and community concepts towards ones of education and community. Education goes well beyond schooling, including all agencies having an organized influence on community development: libraries, voluntary groups, unions, business, human service agencies, government units, as well as schools. This shift requires research to develop nonformal concepts and practices, along with formal pedagogy, to increase the positive impacts of educational networks on community, as well as individual, development. These new directions have not yet significantly modified the traditional meaning of school and community relations.
The Plunge Phase of Friction Stir Welding
NASA Technical Reports Server (NTRS)
Nunes, Arthur; McClure, John; Avila, Ricardo
2005-01-01
Torque and plunge force during the initial plunge phase in Friction Stir Welding were measured for a 0.5 inch diameter pin entering a 2219 aluminum alloy plate. Weld structures were preserved for metallographic observation by making emergency stops at various plunge depths. The plunging pin tool is seen to be surrounded by a very fine grained layer of recrystallized metal extending substantially below the bottom of the pin, implying a shear interface in the metal below and not at the tool-metal interface. Torque and plunge force during the initial plunge phase in Friction Stir Welding are calculated from a straight forward model based on a concept to plastic flow in the vicinity of the plunging tool compatible with structural observations. The concept: a disk of weld metal seized to and rotating with the bottom of the pin is squeezed out laterally by the plunge force and extruded upwards in a hollow cylinder around the tool. As the shear surface separating rotating disk from stationary weld metal engulfs fresh metal, the fresh metal is subjected to severe shear deformation, which results in its recrystallization. Encouraging agreement between computations and measured torque and plunge force is obtained.
Thermodynamically Feasible Kinetic Models of Reaction Networks
Ederer, Michael; Gilles, Ernst Dieter
2007-01-01
The dynamics of biological reaction networks are strongly constrained by thermodynamics. An holistic understanding of their behavior and regulation requires mathematical models that observe these constraints. However, kinetic models may easily violate the constraints imposed by the principle of detailed balance, if no special care is taken. Detailed balance demands that in thermodynamic equilibrium all fluxes vanish. We introduce a thermodynamic-kinetic modeling (TKM) formalism that adapts the concepts of potentials and forces from irreversible thermodynamics to kinetic modeling. In the proposed formalism, the thermokinetic potential of a compound is proportional to its concentration. The proportionality factor is a compound-specific parameter called capacity. The thermokinetic force of a reaction is a function of the potentials. Every reaction has a resistance that is the ratio of thermokinetic force and reaction rate. For mass-action type kinetics, the resistances are constant. Since it relies on the thermodynamic concept of potentials and forces, the TKM formalism structurally observes detailed balance for all values of capacities and resistances. Thus, it provides an easy way to formulate physically feasible, kinetic models of biological reaction networks. The TKM formalism is useful for modeling large biological networks that are subject to many detailed balance relations. PMID:17208985
Terms vs. Concepts - The Case of Weight
NASA Astrophysics Data System (ADS)
Taibu, Rex
2017-01-01
Terminological and conceptual issues surrounding the definition of scientific terms have bothered teachers and students for many years. Some terms such as energy are not even usually defined, although they appear in different contexts of scientific communication, and others such as weight have debatable definitions, and for this reason the term weight is a great example to demonstrate general issues regarding terms and concepts. The term weight is defined in different ways, e.g., as the gravitational force or operationally as the force exerted by the body on its support. In an inertial situation, the magnitude of the gravitational force is equal to that of the support force. However, the two meanings are distinct when the object is in an accelerating situation (e.g., an accelerating elevator or on the surface of a rotating planet). Apart from these dichotomous definitions of weight, there are further language problems associated with each gravitational and operational definition of weight. This paper demonstrates these issues and asserts that arguing for which definition of weight is correct is not a viable approach to solve the language issue. The paper proposes an alternative route to deal with language issues facing weight and other related terms.
An experimental simulation study of four crosswind landing gear concepts
NASA Technical Reports Server (NTRS)
Stubbs, S. M.; Byrdsong, T. A.; Sleeper, R. K.
1975-01-01
An experimental investigation was conducted in order to evaluate several crosswind landing-gear concepts which have a potential application to tricycle-gear-configured, short take-off and landing (STOL) aircraft landing at crab or heading angles up to 30 deg. In this investigation, the landing gears were installed on a dynamic model which had a scaled mass distribution and gear spacing but no aerodynamic similarities when compared with a typical STOL aircraft. The model was operated as a free body with radio-control steering and was launched onto a runway sloped laterally in order to provide a simulated crosswind side force. During the landing rollout, the gear forces and the model trajectory were measured and the various concepts were compared with each other. Within the test limitations, the landing gear system, in which the gears were alined by the pilot and locked in the direction of motion prior to touchdown, gave the smoothest runout behavior with the vehicle maintaining its crab angle throughout the landing runout.
Loading tests of a wing structure for a hypersonic aircraft
NASA Technical Reports Server (NTRS)
Fields, R. A.; Reardon, L. F.; Siegel, W. H.
1980-01-01
Room-temperature loading tests were conducted on a wing structure designed with a beaded panel concept for a Mach 8 hypersonic research airplane. Strain, stress, and deflection data were compared with the results of three finite-element structural analysis computer programs and with design data. The test program data were used to evaluate the structural concept and the methods of analysis used in the design. A force stiffness technique was utilized in conjunction with load conditions which produced various combinations of panel shear and compression loading to determine the failure envelope of the buckling critical beaded panels The force-stiffness data did not result in any predictions of buckling failure. It was, therefore, concluded that the panels were conservatively designed as a result of design constraints and assumptions of panel eccentricities. The analysis programs calculated strains and stresses competently. Comparisons between calculated and measured structural deflections showed good agreement. The test program offered a positive demonstration of the beaded panel concept subjected to room-temperature load conditions.
Analysis of Newton's Third Law Questions on the Force Concepts Inventory at Georgia State University
NASA Astrophysics Data System (ADS)
Oakley, Christopher; Thoms, Brian
2012-03-01
A major emphasis of the Physics Education Research program at Georgia State University is an effort to assess and improve students' understanding of Newton's Laws concepts. As part of these efforts the Force Concepts Inventory (FCI) has been given to students in both the algebra-based and calculus-based introductory physics sequences. In addition, the algebra-based introductory physics sequence is taught in both a SCALE-UP and a traditional lecture format. The results of the FCI have been analyzed by individual question and also as categorized by content. The analysis indicates that students in both algebra and calculus-based courses are successful at overcoming Aristotelian misconceptions regarding Newton's Third Law (N3) in the context of a stationary system. However, students are less successful on N3 questions involving objects in constant motion or accelerating. Interference between understanding of Newton's Second and Third Laws as well as other possible explanations for lower student performance on N3 questions involving non-stationary objects will be discussed.
ERIC Educational Resources Information Center
Ritter, Kurt W.
The author suggests a critical approach to the rhetoric of the American Revolution focusing on the concept of "myth-making. This operates in revolutionary rhetoric when the revolutionist creates a spiritual dynamism for his movement through appeals that suggest the sanction of supra-rational forces. The author applies this concept to the…
Regional Alignment: Phase Zero Logistics Implications
2014-05-01
Brigade TDC Theater Distribution Center TPFDL Time Phased Force Deployment List TSC Theater Sustainment Command v INTRODUCTION Not only are...Center ( TDC ) capability in response to the backlog of supplies and equipment required during major combat operation. The TDC was a contracted...organization, constructed to support units based on amount personnel and equipment. This TDC concept was a part of the logistics concept that supported
Submersible Aircraft Concept Design Study
2010-08-01
capable of submerging at the expense of in-air efficiency; 2. creating a low density submersible requiring dynamic lift to stay submerged at the...density solution would require some additional submergence force. Whilst dynamic lift underwater could be easily achieved by the already present...turbo-prop characteristics for the submersible aircraft concept. Turbo-props are typically specified in terms of shaft horse power ( shp ) rather than
GAMMON: An Approach to the Concept of Strategy in Game-Playing Programs.
ERIC Educational Resources Information Center
Bushey, William Edward
In order to investigate the use of strategies in a game-playing computer program, "Gammon," a computer program that plays Backgammon, was developed. It focuses on the play of a given strategy, as well as the process of strategy selection, and examines the concept of strategy as an integrating and driving force in the play of a game. A…
Integrating concepts and skills: Slope and kinematics graphs
NASA Astrophysics Data System (ADS)
Tonelli, Edward P., Jr.
The concept of force is a foundational idea in physics. To predict the results of applying forces to objects, a student must be able to interpret data representing changes in distance, time, speed, and acceleration. Comprehension of kinematics concepts requires students to interpret motion graphs, where rates of change are represented as slopes of line segments. Studies have shown that majorities of students who show proficiency with mathematical concepts fail accurately to interpret motion graphs. The primary aim of this study was to examine how students apply their knowledge of slope when interpreting kinematics graphs. To answer the research questions a mixed methods research design, which included a survey and interviews, was adopted. Ninety eight (N=98) high school students completed surveys which were quantitatively analyzed along with qualitative information collected from interviews of students (N=15) and teachers ( N=2). The study showed that students who recalled methods for calculating slopes and speeds calculated slopes accurately, but calculated speeds inaccurately. When comparing the slopes and speeds, most students resorted to calculating instead of visual inspection. Most students recalled and applied memorized rules. Students who calculated slopes and speeds inaccurately failed to recall methods of calculating slopes and speeds, but when comparing speeds, these students connected the concepts of distance and time to the line segments and the rates of change they represented. This study's findings will likely help mathematics and science educators to better assist their students to apply their knowledge of the definition of slope and skills in kinematics concepts.
Let's Get Physical: Teaching Physics Through Gymnastics
NASA Astrophysics Data System (ADS)
Sojourner, Elena J.; Burgasser, Adam J.; Weise, Eric D.
2018-01-01
The concept of embodied learning—that we can learn with our bodies and with our minds—is a well-established concept in physics and math education research, and includes symbolic understanding (e.g., gestures that track how students think or facilitate learning to model complex systems of energy flow) as well as the literal experience of exploring physical phenomena through body movements. Sport has long served as a guide for both illustrating and experiencing physical concepts and phenomena, with a particularly relevant example being the sport of gymnastics. Here, the practitioner is subjected to a wide range of forces and torques, and experiences translational and rotational motions, all guided by control of body positioning, shape, strength, and leverage. Smith provides a comprehensive study of the mechanics used to analyze gymnastic movements, which includes core concepts such as force balance, leverage and torque, center of mass and stability, moment of inertia, ballistic motion, pendulum motion, and circular motion. For life science majors, gymnastics also provides relevant physical examples of biomechanics and the physical limits of biological materials (skin, bones, ligaments). The popularity of gymnastics—consider the phenomenon of Simone Biles—makes it broadly accessible and engaging, particularly across genders.
Revealing physical education students’ misconception in sport biomechanics
NASA Astrophysics Data System (ADS)
Kartiko, D. C.
2018-04-01
The aim of this research is reveal Physical Education students’ misconception in several concepts of Sport Biomechanics. The Data of misconception collected by standard question of Diagnostic Test that given to 30 students of Physical Education, Faculty of Sport, State University of Surabaya in academic year 2017/2018. Diagnostic Test completed with CRI (Certainty of Response Index) in order to collect data of students’ certain in answered test. The data result of diagnostic test analysed through compilation graph of CRI right, CRI wrong and right fraction in every single question. Furthermore, students’ answer result of diagnostic test categorized in to 4 quadrants, these: correct concepts, lucky guess, misconceptions, and lack of knowledge. Its categorizing data to know percentage of misconceptions that arise in every concept tested. These sport biomechanics concepts tested are limited on frictional force, deference of distance and displacement, deference of velocity and acceleration, and free fall motion. The result obtained arise misconception in frictional force 52,78%; deference of distance and displacement 36,67%; deference of velocity and acceleration 56,67%; and free fall motion 53,33%. Result of t-test in diagnostic test misconception percentage showed that percentage of misconception arises in every student above 50%.
Shared Voyage: Learning and Unlearning from Remarkable Projects
NASA Technical Reports Server (NTRS)
Laufer, Alexander; Post, Todd; Hoffman, Edward J.
2005-01-01
Shared Voyage is about four remarkable projects: the Advanced Composition Explorer (NASA), the Joint Air-to-Surface Standoff Missile (U.S. Air Force), the Pathfinder Solar-Powered Airplane (NASA), and the Advanced Medium Range Air-to-Air Missile (U.S.Air Force). Each project is presented as a case study comprised of stories collected from key members of the project teams. The stories found in the book are included with the purpose of providing an effective learning source for project management, encouraging the unlearning of outdated project management concepts, and enhancing awareness of the contexts surrounding different projects. Significantly different from project concepts found in most project management literature, Shared Voyage highlights concepts like a will to win, a results-oriented focus, and collaboration through trust. All four project teams researched in this study applied similar concepts; however, they applied them differently, tailoring them to fit the context of their own particular projects. It is clear that the one best way approach which is still the prevailing paradigm in project management literature should be replaced by a new paradigm: Even though general project management principles exist, their successful application depends on the specifics of the situation.
Climate Change Detection and Attribution of Infrared Spectrum Measurements
NASA Technical Reports Server (NTRS)
Phojanamongkolkij, Nipa; Parker, Peter A.; Mlynczak, Martin G.
2012-01-01
Climate change occurs when the Earth's energy budget changes due to natural or possibly anthropogenic forcings. These forcings cause the climate system to adjust resulting in a new climate state that is warmer or cooler than the original. The key question is how to detect and attribute climate change. The inference of infrared spectral signatures of climate change has been discussed in the literature for nearly 30 years. Pioneering work in the 1980s noted that distinct spectral signatures would be evident in changes in the infrared radiance emitted by the Earth and its atmosphere, and that these could be observed from orbiting satellites. Since then, a number of other studies have advanced the concepts of spectral signatures of climate change. Today the concept of using spectral signatures to identify and attribute atmospheric composition change is firmly accepted and is the foundation of the Climate Absolute Radiance and Refractivity Observatory (CLARREO) satellite mission being developed at NASA. In this work, we will present an overview of the current climate change detection concept using climate model calculations as surrogates for climate change. Any future research work improving the methodology to achieve this concept will be valuable to our society.
Development of crashworthy passenger seats for general-aviation aircraft
NASA Technical Reports Server (NTRS)
Reilly, M. J.; Tanner, A. E.
1979-01-01
Two types of energy absorbing passenger seat concepts suitable for installation in light twin-engine fixed wing aircraft were developed. An existing passenger seat for such an aircraft was used to obtain the envelope constraints. Ceiling suspended and floor supported seat concept designs were developed. A restraint system suitable for both concepts was designed. Energy absorbing hardware for both concepts was fabricated and tension and compression tests were conducted to demonstrate the stroking capability and the force deflection characteristics. Crash impact analysis was made and seat loads developed. The basic seat structures were analyzed to determine the adequacy of their strength under impact loading.
Forced Normalization: Antagonism Between Epilepsy and Psychosis.
Kawakami, Yasuhiko; Itoh, Yasuhiko
2017-05-01
The antagonism between epilepsy and psychosis has been discussed for a long time. Landolt coined the term "forced normalization" in the 1950s to describe psychotic episodes associated with the remission of seizures and disappearance of epileptiform activity on electroencephalograms in individuals with epilepsy. Since then, neurologists and psychiatrists have been intrigued by this phenomenon. However, although collaborative clinical studies and basic experimental researches have been performed, the mechanism of forced normalization remains unknown. In this review article, we present a historical overview of the concept of forced normalization, and discuss potential pathogenic mechanisms and clinical diagnosis. We also discuss the role of dopamine, which appears to be a key factor in the mechanism of forced normalization. Copyright © 2017 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Pitcher, Craig; Gao, Yang
2017-03-01
The dual-reciprocating drill (DRD) is a biologically-inspired low-mass alternative to traditional drilling techniques, using backwards-facing teethed halves to grip the surrounding substrate, generating a traction force that reduces the required overhead penetration force. Previous experiments using a proof-of-concept test bench have provided evidence as to the significant role of sideways movements and lateral forces in improving drilling performance. The system is also progressing to a first system prototype concept, in which an actuation mechanism is integrated within the drill heads. To experimentally determine the effect of lateral motions, a new internal actuation mechanism was developed to allow the inclusion of controlled sideways movements, resulting in the creation of the circular and diagonal burrowing motions. This paper presents an investigation into the performance of the reciprocation and burrowing motions by testing them in a planetary regolith simulant. Analysis of force sensor measurements has shown a relationship between the penetration and traction forces and the internal friction of the mechanism and depth achieved. These tests have also experimentally demonstrated the benefit of lateral motions in drilling performance, with both the burrowing mechanisms and drilling tests performed at an angle able to penetrate further than traditional vertical reciprocation, leading to the proposition of new burrowing and diagonal drilling mechanics. From this, a new fully integrated system prototype can be developed which incorporates lateral motions that can optimise the drilling performance.
Spin contribution to the ponderomotive force in a plasma.
Brodin, G; Misra, A P; Marklund, M
2010-09-03
The concept of a ponderomotive force due to the intrinsic spin of electrons is developed. An expression containing both the classical as well as the spin-induced ponderomotive force is derived. The results are used to demonstrate that an electromagnetic pulse can induce a spin-polarized plasma. Furthermore, it is shown that, for certain parameters, the nonlinear backreaction on the electromagnetic pulse from the spin magnetization current can be larger than that from the classical free current. Suitable parameter values for a direct test of this effect are presented.
Adaptive displays and controllers using alternative feedback.
Repperger, D W
2004-12-01
Investigations on the design of haptic (force reflecting joystick or force display) controllers were conducted by viewing the display of force information within the context of several different paradigms. First, using analogies from electrical and mechanical systems, certain schemes of the haptic interface were hypothesized which may improve the human-machine interaction with respect to various criteria. A discussion is given on how this interaction benefits the electrical and mechanical system. To generalize this concept to the design of human-machine interfaces, three studies with haptic mechanisms were then synthesized and analyzed.
2010-09-01
optics, in the eyes of both the CF and NGO participants, was seen, quite literally, as a life and death issue. 3.4 Differences in Organizational...public, both local and at home in Canada. This, in turn, can affect their security and their image in the eyes of their donor, but most importantly...Canadian Forces Leaders, Davis, 2009). Cultural competence is a concept that has its origins in the sociological, anthropological and psychological
A Newtonian interpretation of configurational forces on dislocations and cracks
NASA Astrophysics Data System (ADS)
Ballarini, Roberto; Royer-Carfagni, Gianni
2016-10-01
Configurational forces are fundamental concepts in the description of the motion of dislocations, cracks and other defects that introduce singularities within the solid state. They are defined by considering variations in energies associated with the movement of such defects, and are therefore different from the classical forces that enter the balance laws of classical Newtonian mechanics. Here, it is demonstrated how a configurational force can be viewed as the resultant of the (Newtonian) contact forces acting on the perturbed shape of an object of substance equivalent to the defect, and evaluated in the limit of the shape being restored to the primitive configuration. The expressions for the configurational forces on the paradigmatic examples of cracks and dislocations are in agreement with those determined using classical variational arguments. This finding opens a new prospective in the use of configurational forces by permitting their physical and intuitive visualization.
NASA Astrophysics Data System (ADS)
Maeda, Yusaku; Terao, Kyohei; Shimokawa, Fusao; Takao, Hidekuni
2016-04-01
In this study, the stable detection principle of a MEMS hardness sensor with “reference plane” structure is theoretically analyzed and demonstrated with experimental results. Hardness measurement independent of contact force instability is realized by the optimum design of the reference plane. The fabricated devices were evaluated, and a “shore A” hardness scale (JIS K 6301 A) was obtained as the reference in the range from A1 to A54 under a stable contact force. The contact force dependence on hardness sensor signals was effectively reduced by 96.6% using our reference plane design. Below 5 N contact force, the maximal signal error of hardness is suppressed to A8. This result corresponds to the detection capability for fat hardness, even when the contact force is unstable. Through experiments, stable detection of human body hardness has been demonstrated without any control of contact force.
Stokes versus Basset: comparison of forces governing motion of small bodies with high acceleration
NASA Astrophysics Data System (ADS)
Krafcik, A.; Babinec, P.; Frollo, I.
2018-05-01
In this paper, the importance of the forces governing the motion of a millimetre-sized sphere in a viscous fluid has been examined. As has been shown previously, for spheres moving with a high initial acceleration, the Basset history force should be used, as well as the commonly used Stokes force. This paper introduces the concept of history forces, which are almost unknown to students despite their interesting mathematical structure and physical meaning, and shows the implementation of simple and efficient numerical methods as a MATLAB code to simulate the motion of a falling sphere. An important application of this code could be, for example, the simulation of microfluidic systems, where the external forces are very large and the relevant timescale is in the order of milliseconds to seconds, and therefore the Basset history force cannot be neglected.
NASA Astrophysics Data System (ADS)
Sabin, Suzanne Sells
Using a phenomenographical approach, this study investigates the qualitatively different ways that middle school boys and girls conceptualize aspects of the relationship between force and motion. It is well documented that students enter the classroom with intuitive beliefs that are frequently inconsistent with the Newtonian concept of force. Better known as misconceptions, three such understandings were examined in this study: motion implies force; impetus dissipation; and velocity, or a change in velocity, is proportional to force. With respect to each misconception, potential gender differences in comprehension were examined by monitoring student thinking during the learning process. To gain insight into the prior knowledge of the learner, selected items from the FCI were administered. These conceptions were then compared with the student's qualitative understanding of each physics principle following classroom instruction thereby characterizing the degree of conceptual change exhibited by the learner. After documenting the student's understanding of a given topic, his or her ability to apply these concepts was explored. Not only were students found to harbor misconceptions that served as obstacles to the learning process, these beliefs proved highly contextual and inconsistently applied. Some misconceptions were more prevalent than others. In addition, students who responded with a given misconception in one context often failed to apply the same belief in a different setting. While this pattern of variability was characteristic of all comparison groups, females were generally more likely to continue employing the motion implies force and impetus dissipation misconceptions following instruction. Perhaps more important than any gender specific trend in student thinking, is the number of individuals who continued to apply misconceptions following instruction. The persistence of the learner's intuitive beliefs has serious implications. More work is needed to establish instructional strategies that promote conceptual change. In addition, the gender differences identified in this study warrant further investigation.
Breaking rocks made easy: subcritical processes and tectonic predesign
NASA Astrophysics Data System (ADS)
Voigtlaender, Anne; Krautblatter, Michael
2017-04-01
In geomorphic studies, to change in landforms, e.g. by rock slope failure, fluvial or glacial erosion, a threshold is commonly assumed, which is crossed either by an increase in external driving or a decrease of internal resisting forces, respectively. If the threshold is crossed, bedrock breaks and slope fails, rivers incise and glaciers plug and sew their bed. Here we put forward a focus on the decrease of the resisting forces, as an increase in the driving forces, to match the strength of bedrock, is not that likely. We suggest that the degradation of resisting forces of bedrock can be better explained by subcritical processes like creep, fatigue and stress corrosion interplaying with tectonic predesign. Both concepts, subcritical processes and tectonic predesign have been issued in the last century, but have not been widely accepted nor have their assumptions been explicitly stressed in recent case studies. Moreover both concepts profit especially on scale issues if merged. Subcritical crack growth, includes different mechanisms promoting fractures well below the ultimate strength. Single infinitesimal but irreversible damage and deformations are induced in the material over time. They interact with inherent microstructural flaws and low applied stresses, limiting local strength and macroscopic behavior of bedrock. This reissues the concept of tectonic predesigned, as proposed by A.E. Scheidegger, which not only encompasses structural features that determine the routing of drainage patterns and shear planes, e.g. joints, faults and foliations, but also the (neo)tectonic stress-field and the (in-situ) strain state of bedrocks and mountains. Combining subcritical processes and tectonic predesign we can better explain, why and where we see a dissected, eroded and geomorphic divers' landscape. In this conceptual framework actual magnitudes of the driving forces are accounted for and so is the nature of the bedrock material, to better understand the trajectories of the forms we study, and break rocks easily.
ERIC Educational Resources Information Center
Wright, Sandra K.
2009-01-01
This historical research will provide school leaders with a broad conception of the conditions, forces and processes behind the development of Economics Education. It serves as a case study of past and current practices and approaches to advocacy in economics education. Since it began in 1885, economics education has experienced many obstacles and…
A Full Spectrum Case for the Heavy Force
2011-03-01
PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Professor John Bonin Concepts, Doctrine, and General Officer Updates Office 8. PERFORMING...SPECTRUM CASE FOR THE HEAVY FORCE by Colonel Richard D. Creed, Jr. United States Army Dr. John Bonin Project...8 Ibid.; also. Programs Branch Common Operating Picture 2010 Briefing. 9 Colonel (R) John Bonin , Ph. D., in an email to the author on 21 DEC 10. Dr
ERIC Educational Resources Information Center
De Luca, R.
2009-01-01
It is shown that, by applying elementary concepts in electromagnetism and electrochemistry to a system consisting of salt water flowing in a thin rectangular pipe at an average velocity v[subscript A] under the influence of a transverse magnetic field B[subscript 0], an electromotive force generator can be conceived. In fact, the Lorentz force…
1990-09-01
increasing 2 complexity of Air Force weapon systems makes the estimation of LCC an extremely difficult task. To accomplish this, mathematical models are...maintenance is nearly horizontal. A reduction in this rate from 2.8 to 2.6 (approx. 7%j resulted in cost savings of around 0.1% for the three lvel concept. The
ERIC Educational Resources Information Center
2000
All kids know the word "work." But they probably don't understand that work happens whenever a force is used to move something--whether it's lifting a heavy object or playing on a see-saw. All About Simple Machines introduces kids to the concepts of forces, work and how machines are used to make work easier. Six simple machines are…
Horizons in Learning Innovation through Technology: Prospects for Air Force Education Benefits
2010-06-10
prototyping, and implementation. Successfully implementing disruptive innovations requires change management to help steward the identification ...systems and environments for Air Force education benefits goes beyond the identification and analysis of emerging horizons. Processes and methods...scene, a patrol area, or a suspect lineup (“Augmented- reality,” 2010). Connection to Innovation Triangle. The concepts of LVC and AR are quickly
Laboratory and Space Measurements of the Effects of Gravity
NASA Astrophysics Data System (ADS)
Cruise, A.; Murdin, P.
2000-11-01
Early philosophers such as Aristotle tried to describe the motion of bodies in the Earth's vicinity with concepts that confused the topics of dynamics (the motion of a body under any external force) with the nature of the force (gravitation) itself. The teaching that followed this doctrine lasted until the mid 1600s when difficulties were becoming apparent in explaining, for example, the motion o...
Bridging the Technology Valley of Death in Joint Medical Development
2015-11-01
Force lieutenant colonel, is the Air Force Medical Support Agency Advanced Development Liaison Field Engineer in Falls Church, Virginia. Prusaczyk is...Awareness, communication and coordination may be mini - mal among Service S&T and AD programs. Joint Transition Planning Process A Joint Transition...Human Proof of Phase III NDA/BLA ling Approval, Launch Concept*** Launch Review Program Initiation Materiel Technology Engineering & Production
Motion and Balance. Physical Science in Action[TM]. Schlessinger Science Library. [Videotape].
ERIC Educational Resources Information Center
2000
Motion allows things to get done, to communicate and to travel. But is motion controlled? Students will learn about the universal laws that apply to motion, the forces that cause it and how it is related to balance. They will also discover why motion occurs when forces are out of control and learn more about this interesting concept by viewing…
Collective European Security Forces: An Idea Whose Time Has Come
1990-04-01
undergoing equipment conversion ( Nike ) - units to relocate under new air defense concept (CRCs, Patriot and IHawk units) - units converting by personnel...34Eastern Europe is traditionally one of the most volatile parts of the world. It has remained a volatile region under the Soviet empire. Gorba...levels of general purpose forces with offense-oriented capabilities, namely tanks, artillery, armoured troop carriers (ATCs), strike aircraft and
ERIC Educational Resources Information Center
Carruthers, Rebecca; de Berg, Kevin
2010-01-01
Seventeen Grade Six students were divided into small groups to study the concept of forces in the context of magnets and their properties. The researcher, a pre-service primary school teacher, encouraged the students into conversation about magnets and it was found that, without hesitation, they talked about their prior experience of magnets. The…
Proposed Criteria for Evaluation of the Reliability Improvement Warranty Concept.
1980-06-01
future applications of AFT thesis research. Please return canpleted questionnaires to: AIT/ LSH Cflnesis Feedback), Wright-Patterson AFB, Ohio 45433. 1 ... 1 Overview. .................... 1 Background. ................... 4 II. PROBLEM DEFINITION. ................ 7 Evaluation Progress ............... 7...maintainability of its weapon sys- tem’s equipment (17: 1 ). In an effort to achieve this end, the Air Force, in FY 1969, first applied the concept of the
All about Flight. Physical Science for Children[TM]. Schlessinger Science Library. [Videotape].
ERIC Educational Resources Information Center
2000
Up, up and away! A hot air balloon, an airplane and even the space shuttle all defy the force of gravity, but they all do it in different ways. Children will learn about the basic concepts that make flight possible. With clear demonstrations and a hands-on project, students will be able to understand more easily the basic concepts behind various…
Reshaping USAF Culture and Strategy: Lasting Themes and Emerging Trends
2011-12-12
operations are well-rooted in the air and space experience, near space concepts have struggled to develop the organizational 22 momentum ...space). Nevertheless, by July 2005, the near space concept had achieved sufficient momentum for General Lance Lord (then Commander of Air Force... Bernoulli ) the vertical dimension. Although operating at the upper reaches of the atmosphere, near space flight is bound by Bernoulian principles. The
ERIC Educational Resources Information Center
Mayer, Christine
2014-01-01
In the context of the international exchange of school reform ideas and concepts, the new schools in Hamburg were recognised as exemplary instances of a revolutionary and forceful reform in the public elementary school systems. Based on studies of transfer and their premise that the transnational transfer of ideas, practices and objects does not…
NASA Technical Reports Server (NTRS)
Cole, Jennifer Hansen
2010-01-01
This slide presentation reviews some of the basic principles of aerodynamics. Included in the presentation are: a few demonstrations of the principles, an explanation of the concepts of lift, drag, thrust and weight, a description of Bernoulli's principle, the concept of the airfoil (i.e., the shape of the wing) and how that effects lift, and the method of controlling an aircraft by manipulating the four forces using control surfaces.
Evaluation of the thin deformable active optics mirror concept
NASA Technical Reports Server (NTRS)
Robertson, H. J.
1972-01-01
The active optics concept using a thin deformable mirror has been successfully demonstrated using a 30 in. diameter, 1/2 in. thick mirror and a 61 point matrix of forces for alignment. Many of the problems associated with the design, fabrication, and launch of large aperture diffraction-limited astronomical telescopes have been resolved and experimental data created that can provide accurate predictions of performance in orbit.
Transparent Flexible Electronics By Directed Integration of Inorganic Micro and Nanomaterials
NASA Astrophysics Data System (ADS)
Cole, Jesse J.
This thesis focuses on nanomanufacturing processes for the heterogeneous integration of nanomaterials. Our approaches involved local adjustment of electrostatics at the surfaces to control material flux. Templating of surface electrostatics was implemented differently for three broad concepts resulting in control over nanomaterial synthesis, deposition, and printing. These three general concepts are: (A) Tailored ZnO nanowire synthesis and integration out of the liquid phase; (B) Arc discharge synthesis and continuous nanocluster deposition from the gas phase; (C) Contact electrification and xerographic printing of nanoparticles from the gas phase. Concept (A): We report a method to fabricate and transfer crystalline ZnO with control over location, orientation, size, and shape. The process uses an oxygen plasma treatment in combination with a photoresist pattern on Magnesium-doped GaN substrates to define narrow nucleation regions and attachment points with 100 nanometer scale dimensions. Lateral epitaxial overgrowth follows nucleation to produce single crystalline ZnO which were fabricated into LEDs and photovoltaic cells. Concept (B): We report a gas phase nanoparticle deposition system which shares characteristics with liquid phase electrodeposition. Clusters of charged nanoparticles selectively deposit onto electrically grounded surfaces. Similar to electroplating, the continued deposition of Au nanoparticles onto underlying resistive traces increased overall line conductivity. Alternatively, semiconducting ZnO and Ge nanomaterial sequentially deposited between interdigitated electrodes and served as addressable sensor active areas. Concept (C): We report patterned transfer of charge between conformal material interfaces through a concept referred to as nanocontact electrification. Nanocontacts of different size and shape are formed between surface functionalized polydimethylsiloxane (PDMS) stamps and other dielectric materials (PMMA, SiO 2). Forced delamination and cleavage of the interface yields a well defined charge pattern with a minimal feature size of 100 nm. The process produces charged surfaces and associated fields that exceed the breakdown strength of air leading to strong long range adhesive forces and force distance curves which are recorded over macroscopic distances. The process is applied to fabricate charge patterned surfaces for nanoxerography demonstrating 200 nm resolution nanoparticle prints and applied to thin film electronics where the patterned charges are used to shift the threshold voltages of underlying transistors by over 500 mV.
Development of a structural concept to resist impacts from multiyear ice floes, ridges, and icebergs
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gerwick, B.C.; Potter, R.E.; Rojansky, M.
1984-05-01
Large multi-year ice features and icebergs may have masses ranging up to 20 million tons or more and may move in the open water at speeds up to 1 knot, thus developing tremendous kinetic energy. A stepped structure concept has been developed to resist these impacts and to transfer the resultant forces and moments into the foundation thus developing a relatively high concentrated reaction force against the ice tending to spall and split it, thus causing a multi-modal failure of the ice, as well as using up kinetic energy at a relatively controlled rate. Calculated ice forces and ice failuremore » modes will be presented. The stepped structure concept is primarily applicable to production platforms in water depths of 50 to 200 meters, which are subject to impact of large ice features such as multi-year ridges, floes, and icebergs The resulting global ice loads are reduced by 50 percent or more as compared to those developed by a vertical or a steep sided structure. Overturning moments are reduced, thus reducing maxima soil bearing values. The structure itself is efficient in its use of structural materials, and is practicable for construction in prestressed reinforced concrete or steel/ concrete hybrid construction. It has acceptable draft during tow and can carry a fully outfitted deck. It is stable during all stages of installation.« less
Zajac, Felix E; Neptune, Richard R; Kautz, Steven A
2002-12-01
Current understanding of how muscles coordinate walking in humans is derived from analyses of body motion, ground reaction force and EMG measurements. This is Part I of a two-part review that emphasizes how muscle-driven dynamics-based simulations assist in the understanding of individual muscle function in walking, especially the causal relationships between muscle force generation and walking kinematics and kinetics. Part I reviews the strengths and limitations of Newton-Euler inverse dynamics and dynamical simulations, including the ability of each to find the contributions of individual muscles to the acceleration/deceleration of the body segments. We caution against using the concept of biarticular muscles transferring power from one joint to another to infer muscle coordination principles because energy flow among segments, even the adjacent segments associated with the joints, cannot be inferred from computation of joint powers and segmental angular velocities alone. Rather, we encourage the use of dynamical simulations to perform muscle-induced segmental acceleration and power analyses. Such analyses have shown that the exchange of segmental energy caused by the forces or accelerations induced by a muscle can be fundamentally invariant to whether the muscle is shortening, lengthening, or neither. How simulation analyses lead to understanding the coordination of seated pedaling, rather than walking, is discussed in this first part because the dynamics of pedaling are much simpler, allowing important concepts to be revealed. We elucidate how energy produced by muscles is delivered to the crank through the synergistic action of other non-energy producing muscles; specifically, that a major function performed by a muscle arises from the instantaneous segmental accelerations and redistribution of segmental energy throughout the body caused by its force generation. Part II reviews how dynamical simulations provide insight into muscle coordination of walking.
Non-Newtonian Aspects of Artificial Intelligence
NASA Astrophysics Data System (ADS)
Zak, Michail
2016-05-01
The challenge of this work is to connect physics with the concept of intelligence. By intelligence we understand a capability to move from disorder to order without external resources, i.e., in violation of the second law of thermodynamics. The objective is to find such a mathematical object described by ODE that possesses such a capability. The proposed approach is based upon modification of the Madelung version of the Schrodinger equation by replacing the force following from quantum potential with non-conservative forces that link to the concept of information. A mathematical formalism suggests that a hypothetical intelligent particle, besides the capability to move against the second law of thermodynamics, acquires such properties like self-image, self-awareness, self-supervision, etc. that are typical for Livings. However since this particle being a quantum-classical hybrid acquires non-Newtonian and non-quantum properties, it does not belong to the physics matter as we know it: the modern physics should be complemented with the concept of the information force that represents a bridge to intelligent particle. As a follow-up of the proposed concept, the following question is addressed: can artificial intelligence (AI) system composed only of physical components compete with a human? The answer is proven to be negative if the AI system is based only on simulations, and positive if digital devices are included. It has been demonstrated that there exists such a quantum neural net that performs simulations combined with digital punctuations. The universality of this quantum-classical hybrid is in capability to violate the second law of thermodynamics by moving from disorder to order without external resources. This advanced capability is illustrated by examples. In conclusion, a mathematical machinery of the perception that is the fundamental part of a cognition process as well as intelligence is introduced and discussed.
NASA Astrophysics Data System (ADS)
Ishimoto, Michi; Thornton, Ronald K.; Sokoloff, David R.
2014-12-01
This study assesses the Japanese translation of the Force and Motion Conceptual Evaluation (FMCE). Researchers are often interested in comparing the conceptual ideas of students with different cultural backgrounds. The FMCE has been useful in identifying the concepts of English-speaking students from different backgrounds. To identify effectively the conceptual ideas of Japanese students and to compare them to those of their English-speaking counterparts, more work is required. Because of differences between the Japanese and English languages, and between the Japanese and American educational systems, it is important to assess the Japanese translation of the FMCE, a conceptual evaluation originally developed in English for American students. To assess its appropriateness, we examined the performance of a large sample of students on the translated version of the FMCE and then compared the results to those of English-speaking students. The data comprise the pretest results of 1095 students, most of whom were first-year students at a midlevel engineering school between 2003 and 2012. Basic statistics and the classical test theory indices of the translated FMCE indicate that its reliability and discrimination are appropriate to assess Japanese students' concepts about force and motion. In general, the preconcepts of Japanese students assessed with the Japanese translation of the FMCE are quite similar to those of American students assessed with the FMCE, thereby supporting the validity of the translated version. However, our findings do show (1) that only a small percentage of Japanese students grasped Newtonian concepts and (2) that the percentage of Japanese students who used two different concept models together to answer some questions seems to be higher than that of American students.
Why advanced computing? The key to space-based operations
NASA Astrophysics Data System (ADS)
Phister, Paul W., Jr.; Plonisch, Igor; Mineo, Jack
2000-11-01
The 'what is the requirement?' aspect of advanced computing and how it relates to and supports Air Force space-based operations is a key issue. In support of the Air Force Space Command's five major mission areas (space control, force enhancement, force applications, space support and mission support), two-fifths of the requirements have associated stringent computing/size implications. The Air Force Research Laboratory's 'migration to space' concept will eventually shift Science and Technology (S&T) dollars from predominantly airborne systems to airborne-and-space related S&T areas. One challenging 'space' area is in the development of sophisticated on-board computing processes for the next generation smaller, cheaper satellite systems. These new space systems (called microsats or nanosats) could be as small as a softball, yet perform functions that are currently being done by large, vulnerable ground-based assets. The Joint Battlespace Infosphere (JBI) concept will be used to manage the overall process of space applications coupled with advancements in computing. The JBI can be defined as a globally interoperable information 'space' which aggregates, integrates, fuses, and intelligently disseminates all relevant battlespace knowledge to support effective decision-making at all echelons of a Joint Task Force (JTF). This paper explores a single theme -- on-board processing is the best avenue to take advantage of advancements in high-performance computing, high-density memories, communications, and re-programmable architecture technologies. The goal is to break away from 'no changes after launch' design to a more flexible design environment that can take advantage of changing space requirements and needs while the space vehicle is 'on orbit.'
Reconfigurable and non-volatile vertical magnetic logic gates
DOE Office of Scientific and Technical Information (OSTI.GOV)
Butler, J., E-mail: jbutl001@ucr.edu; Lee, B.; Shachar, M.
2014-04-28
In this paper, we discuss the concept and prototype fabrication of reconfigurable and non-volatile vertical magnetic logic gates. These gates consist of two input layers and a RESET layer. The RESET layer allows the structure to be used as either an AND or an OR gate, depending on its magnetization state. To prove this concept, the gates were fabricated using a multi-layered patterned magnetic media, in which three magnetic layers are stacked and exchange-decoupled via non-magnetic interlayers. We demonstrate the functionality of these logic gates by conducting atomic force microscopy and magnetic force microscopy (MFM) analysis of the multi-layered patternedmore » magnetic media. The logic gates operation mechanism and fabrication feasibility are both validated by the MFM imaging results.« less
Nonlinear normal vibration modes in the dynamics of nonlinear elastic systems
NASA Astrophysics Data System (ADS)
Mikhlin, Yu V.; Perepelkin, N. V.; Klimenko, A. A.; Harutyunyan, E.
2012-08-01
Nonlinear normal modes (NNMs) are a generalization of the linear normal vibrations. By the Kauderer-Rosenberg concept in the regime of the NNM all position coordinates are single-values functions of some selected position coordinate. By the Shaw-Pierre concept, the NNM is such a regime when all generalized coordinates and velocities are univalent functions of a couple of dominant (active) phase variables. The NNMs approach is used in some applied problems. In particular, the Kauderer-Rosenberg NNMs are analyzed in the dynamics of some pendulum systems. The NNMs of forced vibrations are investigated in a rotor system with an isotropic-elastic shaft. A combination of the Shaw-Pierre NNMs and the Rauscher method is used to construct the forced NNMs and the frequency responses in the rotor dynamics.
Greenhouse Effect, Radiative Forcing and Climate Sensitivity
NASA Astrophysics Data System (ADS)
Ponater, Michael; Dietmüller, Simone; Sausen, Robert
Temperature conditions and climate on Earth are controlled by the balance between absorbed solar radiation and outgoing terrestrial radiation. The greenhouse effect is a synonym for the trapping of infrared radiation by radiatively active atmospheric constituents. It generally causes a warming of the planet's surface, compared to the case without atmosphere. Perturbing the radiation balance of the planet, e.g., by anthropogenic greenhouse gas emissions, induces climate change. Individual contributions to a total climate impact are usually quantified and ranked in terms of their respective radiative forcing. This method involves some limitations, because the effect of the external forcing is modified by radiative feedbacks. Here the current concept of radiative forcing and potential improvements are explained.
NASA Technical Reports Server (NTRS)
Hayashi, Miwa; Ravinder, Ujwala; McCann, Robert S.; Beutter, Brent; Spirkovska, Lily
2009-01-01
Performance enhancements associated with selected forms of automation were quantified in a recent human-in-the-loop evaluation of two candidate operational concepts for fault management on next-generation spacecraft. The baseline concept, called Elsie, featured a full-suite of "soft" fault management interfaces. However, operators were forced to diagnose malfunctions with minimal assistance from the standalone caution and warning system. The other concept, called Besi, incorporated a more capable C&W system with an automated fault diagnosis capability. Results from analyses of participants' eye movements indicate that the greatest empirical benefit of the automation stemmed from eliminating the need for text processing on cluttered, text-rich displays.
Molecular Force Spectroscopy on Cells
NASA Astrophysics Data System (ADS)
Liu, Baoyu; Chen, Wei; Zhu, Cheng
2015-04-01
Molecular force spectroscopy has become a powerful tool to study how mechanics regulates biology, especially the mechanical regulation of molecular interactions and its impact on cellular functions. This force-driven methodology has uncovered a wealth of new information of the physical chemistry of molecular bonds for various biological systems. The new concepts, qualitative and quantitative measures describing bond behavior under force, and structural bases underlying these phenomena have substantially advanced our fundamental understanding of the inner workings of biological systems from the nanoscale (molecule) to the microscale (cell), elucidated basic molecular mechanisms of a wide range of important biological processes, and provided opportunities for engineering applications. Here, we review major force spectroscopic assays, conceptual developments of mechanically regulated kinetics of molecular interactions, and their biological relevance. We also present current challenges and highlight future directions.
Phase-resolved fluid dynamic forces of a flapping foil energy harvester based on PIV measurements
NASA Astrophysics Data System (ADS)
Liburdy, James
2017-11-01
Two-dimensional particle image velocimetry measurements are performed in a wind tunnel to evaluate the spatial and temporal fluid dynamic forces acting on a flapping foil operating in the energy harvesting regime. Experiments are conducted at reduced frequencies (k = fc/U) of 0.05 - 0.2, pitching angle of, and heaving amplitude of A / c = 0.6. The phase-averaged pressure field is obtained by integrating the pressure Poisson equation. Fluid dynamic forces are then obtained through the integral momentum equation. Results are compared with a simple force model based on the concept of flow impulse. These results help to show the detailed force distributions, their transient nature and aide in understanding the impact of the fluid flow structures that contribute to the power production.
2015-12-01
Defense University Center for Advanced Concepts and Technology, 1996). 9 the use of force. War, of course...however, designed for somewhat different undertaking from those to which the armed forces of America and Britain found themselves committed.”24 In the ...alone; a DIME approach is necessary. The fifth chapter explores selected effects, implications, and consequences for future military operations.
Space station operations task force. Panel 4 report: Management integration
NASA Technical Reports Server (NTRS)
1987-01-01
The Management Integration Panel of the Space Station Operations Task Force was chartered to provide a structure and ground rules for integrating the efforts of the other three panels and to address a number of cross cutting issues that affect all areas of space station operations. Issues addressed include operations concept implementation, alternatives development and integration process, strategic policy issues and options, and program management emphasis areas.
Army-Marine Integration, Volume 2, Number 10-55. Observations, Insights, and Lessons
2010-08-01
can be tailored to combat any enemy force worldwide. The effectiveness of this revolutionary concept was displayed, and its fundamentals reinforced...evolved in Iraq’s western sector and the insurgents changed strategy, the sustainment demands required of coalition forces changed. The fundamentals of...of the MEU, and contracted civilian logistics within the area of operations. Getting the right mix of capabilities at each location was fundamental
Deriving the Work Done by an Inverse Square Force in Non-Calculus-Based Introductory Physics Courses
ERIC Educational Resources Information Center
Hu, Ben Yu-Kuang
2012-01-01
I describe a method of evaluating the integral of 1/r[superscript 2] with respect to r that uses only algebra and the concept of area underneath a curve, and which does not formally employ any calculus. This is useful for algebra-based introductory physics classes (where the use of calculus is forbidden) to derive the work done by the force of one…
Airsea Battle: Can the Air Force and the Navy Get Along
2011-06-01
staffs at headquarters, Special Operations Command – Korea (SOCKOR) and at Joint Special Operations Task Force – Philippines (JSOTF- P ). His most...Detachment (JSOAD) deputy commander for JSOTF- P . Major Kobs holds a Bachelors of Arts Degree in Political Science from the University of New...1894), p . 26. concept, Glenn H. Curtiss agreed to instruct naval officers for the creation of a naval aviation program. Lieutenant T.G
Cross-Domain Synergy: Using Artillery in the Fight for Sea Control
2017-04-28
weapon systems designed to contest operational access to joint forces have given many countries low-cost options to prevent intrusion into their...systems designed to contest operational access to joint forces have given many countries low-cost options to prevent intrusion into their...1 The concept of anti-access is not new. The Great Wall of China and Athenian walls demonstrate this strategy has existed for
Developing Air Force Strategic Leadership - A Career Long Process
2012-05-14
experience, the Air Force as an organization is more prone to parochialism, myopia and monistic thinking. 27 Besides providing a historical record of... myopia and monistic thinking.” 120 Worden also claims the uniformity of perspective hindered strategic leaders from understanding or recognizing the...discussions in a virtual setting. While the use of social media is a developing concept, some officers have enjoyed early opportunities for PME or
Professional Military Education for Life (PME4L)
2014-12-08
The Air Force embracing a continuous educational model which integrates CPE concepts in order to persistently develop professional Airmen, engages...exposure to new ideas and career fields. Due to PME’s importance in an Airman’s career development, PME should be a continuous process with the...current PME courses as anchors. PME4L complements traditional Air Force PME and invests in Airmen at all levels. This paper presents a Continuous
The U.S. Air Force Transformation Flight Plan
2003-11-01
at Buckley Air Force Base, Colorado. Reserve Associate and Active Associate units have proven that this concept works and benef its the Active and...munitions manufactured from nano-particles, whose virtually all-surface structure yields unprecedented “burn-rates” (extreme explosiveness), promise far...systems for a common operating system, and a suite of remotely operated sensors, weapons, and robotics . Also included are a group of non-lethal weapon
Leadership Theory and Practice: Where East Meets West
1989-06-01
leadership concepts can be assimilated to good advantage by the Chinese. and what additional research ei’forts for the armed forces of the Republic... research ef- forts for the armed forces of the Republic of China should be undertaken. The this7s "su ,, L.,uitJ _ description of the eCHO sampiing...29 A. THE ECHO SAMPLING TECHNIQUE ....................... 29 B. THE MCBER SAMPLING METHOD .. ....................... 33 IV. CRITICAL
Potential System Vulnerabilities of a Network Enabled Force
2004-09-01
of trust in information, loss of context and awareness of others’ needs and reduction of social cohesion . Science - (more specifically systems...and Technology Damaging Social Cohesion NCW champions the concept of dispersed forces as a means to generate effects through approaches other than...Mission Grouping Damaging Social Cohesion This is a slight variation on the vulnerability expressed in 3.9.6 above. If we have agility in mission
Evaluation and review of the safety management system implementation in the Royal Thai Air Force
NASA Astrophysics Data System (ADS)
Chaiwan, Sakkarin
This study was designed to determine situation and effectiveness of the safety management system currently implemented in the Royal Thai Air Force. Reviewing the ICAO's SMS and the RTAF's SMS was conducted to identify similarities and differences between the two safety management systems. Later, the researcher acquired safety statistics from the RTAF Safety Center to investigate effectiveness of its safety system. The researcher also collected data to identify other factors affecting effectiveness of the safety system during conducting in-depth interviews. Findings and Conclusions: The study shows that the Royal Thai Air Force has never applied the International Civil Aviation Organization's Safety management System to its safety system. However, the RTAF's SMS and the ICAO's SMS have been developed based on the same concepts. These concepts are from Richard H. Woods's book, Aviation safety programs: A management handbook. However, the effectiveness of the Royal Thai Air Force's safety system is in good stance. An accident rate has been decreasing regularly but there are no known factors to describe the increasing rate, according to the participants' opinion. The participants have informed that there are many issues to be resolved to improve the RTAF's safety system. Those issues are cooperation among safety center's staffs, attitude toward safety of the RTAF senior commanders, and safety standards.
Effects-Based Approaches to Operations: Canadian Perspectives
2008-04-01
total wars that characterized much of the 20th century. To many, the aeroplane offered the means to achieve this dream . Germany and Great... lucid and coherent introduction to the concept. William A. Owens, “The Once and Future Revolution in Military Affairs,” Joint Force Quarterly 31...must read this article as it provides a clear and lucid series of arguments against the adoption of the concept that merit consideration
Concept Development for Future Domains: A New Method of Knowledge Elicitation
2005-06-01
Procedure: U.S. Army Research Institute for the Behavioral and Social Sciences (ARI) examined methods to generate, refine, test , and validate new...generate, elaborate, refine, describe, test , and validate new Future Force concepts relating to doctrine, tactics, techniques, procedures, unit and team...System (Harvey, 1993), and the Job Element Method (Primoff & Eyde , 1988). Figure 1 provides a more comprehensive list of task analytic methods. Please see
Fire Fighting Task Force (FIRE)
1989-04-01
and fdenify by block number) ~’This study is part of ~a contining effort to develop soldier data and performance algorithms (pergorithus) needed to...similar to combat, results will be useful in developing algorithms and data for use in US Army Concepts Analysis Agency (CAA) combat models. THE...dimensions. The US Army Concepts Analysis Agency (CAA) is committed to adding the soldier variables and algorithms that are necessary to fully represent
Warrior Ethos Revisited: Implications for the Future
2011-03-15
ambiguous circumstances which will require a high degree of moral judgment in the reasoned application of force. Adapting Army culture to meet these...relationships and places high priority on the development of moral character. The Army Capstone Concept 2016-2028 argues that while the character of war...assessment of the situation”.5 As the Army through its Capstone Concept seeks to define required future capabilities, what cultural changes if any
Catalog of Air Force Weather Technical Documents, 1941-2006
2006-05-19
radiosondes in current use in USA. Elementary discussion of statistical terms and concepts used for expressing accuracy or error is discussed. AWS TR 105...Techniques, Appendix B: Vorticity—An Elementary Discussion of the Concept, August 1956, 27pp. Formerly AWSM 105– 50/1A. Provides the necessary back...steps involved in ordinary multiple linear regression. Conditional probability is calculated using transnormalized variables in the multivariate normal
Survey of Beamed Energy Propulsion Concepts by the MSFC Space Environmental Effects Team
NASA Technical Reports Server (NTRS)
Gray, P. A.; Nehls, M. K.; Edwards, D. L.; Carruth, M. R., Jr.; Munafo, Paul M. (Technical Monitor)
2002-01-01
This will be a survey paper of work that was performed by the Space Environmental Effects Team at NASA's Marshall Space Flight Center in the area of laser energy propulsion concepts. Two types of laser energy propulsion techniques were investigated. The first was ablative propulsion, which used a pulsed ruby laser impacting on single layer coatings and films. The purpose of this investigation was to determine the laser power density that produced an optimum coupling coefficient for each type of material tested. A commercial off-the-shelf multi-layer film was also investigated for possible applications in ablative micro-thrusters, and its optimum coupling coefficient was determined. The second type of study measured the purely photonic force provided by a 300W CW YAG laser. In initial studies, the photon force resulting from the momentum of incident photons was measured directly using a vacuum compatible microbalance and these results were compared to theory. Follow-on work used the same CW laser to excite a stable optical cavity for the purpose of amplifying the available force from incident photons.
Exoskeleton master controller with force-reflecting telepresence
NASA Technical Reports Server (NTRS)
Burke, James B.; Bartholet, Stephen J.; Nelson, David K.
1992-01-01
A thorough understanding of the requirements for successful master-slave robotic systems is becoming increasingly desirable. Such systems can aid in the accomplishment of tasks that are hazardous or inaccessible to humans. Although a history of use has proven master-slave systems to be viable, system requirements and the impact of specifications on the human factors side of system performance are not well known. In support of the next phase of teleoperation research being conducted at the Armstrong Research Laboratory, a force-reflecting, seven degree of freedom exoskeleton for master-slave teleoperation has been concepted, and is presently being developed. The exoskeleton has a unique kinematic structure that complements the structure of the human arm. It provides a natural means for teleoperating a dexterous, possibly redundant manipulator. It allows ease of use without operator fatigue and faithfully follows human arm and wrist motions. Reflected forces and moments are remotely transmitted to the operator hand grip using a cable transmission scheme. This paper presents the exoskeleton concept and development results to date. Conceptual design, hardware, algorithms, computer architecture, and software are covered.
A spatiotemporal structure: common to subatomic systems, biological processes, and economic cycles
NASA Astrophysics Data System (ADS)
Naitoh, Ken
2012-03-01
A theoretical model derived based on a quasi-stability concept applied to momentum conservation (Naitoh, JJIAM, 2001, Artificial Life Robotics, 2008, 2010) has revealed the spatial structure of various systems. This model explains the reason why particles such as biological cells, nitrogenous bases, and liquid droplets have bimodal size ratios of about 2:3 and 1:1. This paper shows that the same theory holds true for several levels of parcels from baryons to stars in the cosmos: specifically, at the levels of nuclear force, van der Waals force, surface tension, and the force of gravity. A higher order of analysis clarifies other asymmetric ratios related to the halo structure seen in atoms and amino acids. We will also show that our minimum hypercycle theory for explaining the morphogenetic cycle (Naitoh, Artificial Life Robotics, 2008) reveals other temporal cycles such as those of economic systems and the circadian clock as well as the fundamental neural network pattern (topological pattern). Finally, a universal equation describing the spatiotemporal structure of several systems will be derived, which also leads to a general concept of quasi-stability.
The Use of Remote Sensing to Resolve the Aerosol Radiative Forcing
NASA Technical Reports Server (NTRS)
Kaufman, Y. J.; Tanre, D.; Remer, Lorraine
1999-01-01
Satellites are used for remote sensing of aerosol optical thickness and optical properties in order to derive the aerosol direct and indirect radiative forcing of climate. Accuracy of the derived aerosol optical thickness is used as a measure of the accuracy in deriving the aerosol radiative forcing. Several questions can be asked to challenge this concept. Is the accuracy of the satellite-derived aerosol direct forcing limited to the accuracy of the measured optical thickness? What are the spectral bands needed to derive the total aerosol forcing? Does most of the direct or indirect aerosol forcing of climate originate from regions with aerosol concentrations that are high enough to be detected from space? What should be the synergism ground-based and space-borne remote sensing to solve the problem? We shall try to answer some of these questions, using AVIRIS airborne measurements and simulations.
On the causal structure between CO2 and global temperature
Stips, Adolf; Macias, Diego; Coughlan, Clare; Garcia-Gorriz, Elisa; Liang, X. San
2016-01-01
We use a newly developed technique that is based on the information flow concept to investigate the causal structure between the global radiative forcing and the annual global mean surface temperature anomalies (GMTA) since 1850. Our study unambiguously shows one-way causality between the total Greenhouse Gases and GMTA. Specifically, it is confirmed that the former, especially CO2, are the main causal drivers of the recent warming. A significant but smaller information flow comes from aerosol direct and indirect forcing, and on short time periods, volcanic forcings. In contrast the causality contribution from natural forcings (solar irradiance and volcanic forcing) to the long term trend is not significant. The spatial explicit analysis reveals that the anthropogenic forcing fingerprint is significantly regionally varying in both hemispheres. On paleoclimate time scales, however, the cause-effect direction is reversed: temperature changes cause subsequent CO2/CH4 changes. PMID:26900086
Forced underwater laminar flows with active magnetohydrodynamic metamaterials
NASA Astrophysics Data System (ADS)
Culver, Dean; Urzhumov, Yaroslav
2017-12-01
Theory and practical implementations for wake-free propulsion systems are proposed and proven with computational fluid dynamic modeling. Introduced earlier, the concept of active hydrodynamic metamaterials is advanced by introducing magnetohydrodynamic metamaterials, structures with custom-designed volumetric distribution of Lorentz forces acting on a conducting fluid. Distributions of volume forces leading to wake-free, laminar flows are designed using multivariate optimization. Theoretical indications are presented that such flows can be sustained at arbitrarily high Reynolds numbers. Moreover, it is shown that in the limit Re ≫102 , a fixed volume force distribution may lead to a forced laminar flow across a wide range of Re numbers, without the need to reconfigure the force-generating metamaterial. Power requirements for such a device are studied as a function of the fluid conductivity. Implications to the design of distributed propulsion systems underwater and in space are discussed.
Multiplex Particle Focusing via Hydrodynamic Force in Viscoelastic Fluids
NASA Astrophysics Data System (ADS)
Lee, Doo Jin; Brenner, Howard; Youn, Jae Ryoun; Song, Young Seok
2013-11-01
We introduce a multiplex particle focusing phenomenon that arises from the hydrodynamic interaction between the viscoelastic force and the Dean drag force in a microfluidic device. In a confined microchannel, the first normal stress difference of viscoelastic fluids results in a lateral migration of suspended particles. Such a viscoelastic force was harnessed to focus different sized particles in the middle of a microchannel, and spiral channel geometry was also considered in order to take advantage of the counteracting force, Dean drag force that induces particle migration in the outward direction. For theoretical understanding, we performed a numerical analysis of viscoelastic fluids in the spiral microfluidic channel. From these results, a concept of the `Dean-coupled Elasto-inertial Focusing band (DEF)' was proposed. This study provides in-depth physical insight into the multiplex focusing of particles that can open a new venue for microfluidic particle dynamics for a concrete high throughput platform at microscale.
Jackson, Todd, and the concept of "discharge" in epilepsy.
Reynolds, Edward H
2007-11-01
To explore the historical origins of the modern concept of electrical discharges in the brain in epilepsy. I have examined the writings of Hughlings Jackson (1835-1911) and Robert Bentley Todd (1809-1860), especially their Lumleian Lectures on convulsive disorders to the Royal College of Physicians of 1890 and 1849, respectively; and also the influence of Herbert Spencer (1820-1903) on the former and Michael Faraday (1791-1867) on the latter. Contrary to the widely taught view that Jackson was the first to propose electrical discharges in epilepsy it is clear that the discharges suggested by Jackson, influenced by the evolutionary philosopher, Herbert Spencer, were chemical, based on katabolism and anabolism. Jackson had no understanding or proposal based on physics or electricity. On the other hand, Todd had earlier proposed and described electrical concepts of discharges in epilepsy, influenced by his contemporary and colleague in London, Michael Faraday, who at the time was laying the foundations of our modern understanding of electricity and magnetism. Todd and Faraday saw "nervous polarity" as another polar force interchangeable with the polar forces of electricity and magnetism.
Gravitational forces and moments on spacecraft
NASA Technical Reports Server (NTRS)
Kane, T. R.; Likins, P. W.
1975-01-01
The solution of problems of attitude dynamics of spacecraft and the influence of gravitational forces and moments is examined. Arguments are presented based on Newton's law of gravitation, and employing the methods of Newtonian (vectorial) mechanics, with minimal recourse to the classical concepts of potential theory. The necessary ideas were developed and relationships were established to permit the representation of gravitational forces and moments exerted on bodies in space by other bodies, both in terms involving the mass distribution properties of the bodies, and in terms of vector operations on those scalar functions classically described as gravitational potential functions.
Application of green concept in mechanical design and manufacture
NASA Astrophysics Data System (ADS)
Liu, Xing ping
2017-11-01
With the development of productive forces, the relationship between human and nature is becoming tight increasingly, especially environmental pollution and resource consumption that comes from equipment manufacturing industry mainly. Green development concept is a new concept which can solve the current ecological environment. The philosophical foundation and theoretical basis of green idea are expounded through the study of scientific development and green concept. The difference between the traditional design and the green design is analyzed; the meaning and content of the mechanical design for green concept are discussed. And the evaluation method of green design is discussed too. The significance of green development concept in the mechanical design and manufacturing science is pinpointed clearly. The results show that the implementation of green design under the mechanical design, from the source of pollution control to achieve green manufacturing, is the only way to achieve sustainable development.
Fu, Qiushi; Santello, Marco
2018-01-01
The concept of postural synergies of the human hand has been shown to potentially reduce complexity in the neuromuscular control of grasping. By merging this concept with soft robotics approaches, a multi degrees of freedom soft-synergy prosthetic hand [SoftHand-Pro (SHP)] was created. The mechanical innovation of the SHP enables adaptive and robust functional grasps with simple and intuitive myoelectric control from only two surface electromyogram (sEMG) channels. However, the current myoelectric controller has very limited capability for fine control of grasp forces. We addressed this challenge by designing a hybrid-gain myoelectric controller that switches control gains based on the sensorimotor state of the SHP. This controller was tested against a conventional single-gain (SG) controller, as well as against native hand in able-bodied subjects. We used the following tasks to evaluate the performance of grasp force control: (1) pick and place objects with different size, weight, and fragility levels using power or precision grasp and (2) squeezing objects with different stiffness. Sensory feedback of the grasp forces was provided to the user through a non-invasive, mechanotactile haptic feedback device mounted on the upper arm. We demonstrated that the novel hybrid controller enabled superior task completion speed and fine force control over SG controller in object pick-and-place tasks. We also found that the performance of the hybrid controller qualitatively agrees with the performance of native human hands. PMID:29375360
Generalized derivation of the added-mass and circulatory forces for viscous flows
NASA Astrophysics Data System (ADS)
Limacher, Eric; Morton, Chris; Wood, David
2018-01-01
The concept of added mass arises from potential flow analysis and is associated with the acceleration of a body in an inviscid irrotational fluid. When shed vorticity is modeled as vortex singularities embedded in this irrotational flow, the associated force can be superimposed onto the added-mass force due to the linearity of the governing Laplace equation. This decomposition of force into added-mass and circulatory components remains common in modern aerodynamic models, but its applicability to viscous separated flows remains unclear. The present work addresses this knowledge gap by presenting a generalized derivation of the added-mass and circulatory force decomposition which is valid for a body of arbitrary shape in an unbounded, incompressible fluid domain, in both two and three dimensions, undergoing arbitrary motions amid continuous distributions of vorticity. From the general expression, the classical added-mass force is rederived for well-known canonical cases and is seen to be additive to the circulatory force for any flow. The formulation is shown to be equivalent to existing theoretical work under the specific conditions and assumptions of previous studies. It is also validated using a numerical simulation of a pitching plate in a steady freestream flow, conducted by Wang and Eldredge [Theor. Comput. Fluid Dyn. 27, 577 (2013), 10.1007/s00162-012-0279-5]. In response to persistent confusion in the literature, a discussion of the most appropriate physical interpretation of added mass is included, informed by inspection of the derived equations. The added-mass force is seen to account for the dynamic effect of near-body vorticity and is not (as is commonly claimed) associated with the acceleration of near-body fluid which "must" somehow move with the body. Various other consequences of the derivation are discussed, including a concept which has been labeled the conservation of image-vorticity impulse.
NASA Technical Reports Server (NTRS)
Hollrock, R. H.; Barzda, J. J.
1972-01-01
To increase aircrewmen's chances for safe rescue in combat zones, the armed forces are investigating advanced escape and rescue concepts that will provide independent flight after ejection and thus reduce the risk of capture. One of the candidate concepts is discussed; namely, a stowable autogyro that serves as the crewman's seat during normal operations and automatically converts to a flight vehicle after ejection. Discussed are (1) the mechanism subsystems that the concept embodies to meet the weight and cockpit-packaging constraints and (2) tests that demonstrated the technical feasibility of the stowage, deployment, and flight operation of the rotor lift system.
Hybrid propulsion technology program: Phase 1. Volume 3: Thiokol Corporation Space Operations
NASA Technical Reports Server (NTRS)
Schuler, A. L.; Wiley, D. R.
1989-01-01
Three candidate hybrid propulsion (HP) concepts were identified, optimized, evaluated, and refined through an iterative process that continually forced improvement to the systems with respect to safety, reliability, cost, and performance criteria. A full scale booster meeting Advanced Solid Rocket Motor (ASRM) thrust-time constraints and a booster application for 1/4 ASRM thrust were evaluated. Trade studies and analyses were performed for each of the motor elements related to SRM technology. Based on trade study results, the optimum HP concept for both full and quarter sized systems was defined. The three candidate hybrid concepts evaluated are illustrated.
Foreign Police Development: The Third Time’s the Charm
2010-02-10
inclusive concept of a standing Interagency Task Force ( IATF ) headquarters, which would deploy on short notice as part of a combatant command’s...COCOM) combined joint task force (CJTF). In this case, the President would appoint a senior civilian to lead the IATF and its fully integrated civil...agencies in support seems the most practical, flexible, and cost-effective. Part of that IATF would be a fully integrated police development team
Linear thermal circulator based on Coriolis forces.
Li, Huanan; Kottos, Tsampikos
2015-02-01
We show that the presence of a Coriolis force in a rotating linear lattice imposes a nonreciprocal propagation of the phononic heat carriers. Using this effect we propose the concept of Coriolis linear thermal circulator which can control the circulation of a heat current. A simple model of three coupled harmonic masses on a rotating platform permits us to demonstrate giant circulating rectification effects for moderate values of the angular velocities of the platform.
AF Security Forces and Building Partner Capacity Examining Cultural Competency as a Force Enabler
2017-02-03
key leaders taking on these missions across any foreign culture. The concept of “cultural mindfulness ” alone would be a prudent tool to any BPC...team member executing key leader engagements. “ Mindfulness refers to the heightened awareness of our own thinking patterns, affective reactions, and...New York: McGraw Hill. Pp. 5-11. Ting-Toomey, Stella. 1999. “ Mindful Intercultural Verbal Communication.” Communicating Across Cultures. New
Experimental Aerodynamic Facilities of the Aerodynamics Research and Concepts Assistance Section
1983-02-01
experimental data desired. Internal strain gage balances covering a range of sizes and load capabilities are available for static force and moment tests...tunnel. Both sting and side wall model mounts are available which can be adapted to a variety of internal strain gage balance systems for force and...model components or liquids in the test section. A selection of internal and external strain gage balances and associated mounting fixtures are
Unintended Consequences of the Goldwater-Nichols Act (Joint Force Quarterly, Spring 1998)
1998-01-01
Armed Forces to achieve mili- tary success, the unified direction of DOD neces- sary for budgetary efficiency, and the separation of powers demanded by...its actions. The Constitution has stood for two centuries precisely because it flexibly applies simple concepts such as the separation of powers and...replaced, it has created a national military command structure that ignores the separation of powers . The amended National Security Act has consolidated
The Chinese Air Force: Evolving Concepts, Roles, and Capabilities
2012-01-01
5 The Missions of the People’s Liberation Army Air Force . . . 133 Murray Scot Tanner Chapter 6 The Development of the PLAAF’s Doctrine...the Military Region (MR) Headquarters. There are no indications this pattern of army domination will change in the next decade.” Murray Scot Tanner, a...his- tory, one can find remarkable threads of continuity. Early aircraft, though but fragile contraptions of wood and canvas, exploited the same
Airborne Next: Rethinking Airborne Organization and Applying New Concepts
2015-06-01
9 Kenneth Macksey, Guderian: Panzer General-revised EDITION (South Yorkshire, England: Greenhill Books, 2003), 1–20. 10 Dr. John Arquilla...Airborne Operations: Field Manual 90=26, 1–5. 14 The 1st Special Forces Regiment has five active Special Forces Groups (1st, 3rd, 5th , 7th, 10th...Oxford University Press, 1981). Headrick, in his book, describes the interplay between technology and imperialism. For the purposes of this research
Unity of Command and Interdiction
1994-07-01
8217RobWt F. Fuftff Idea, Cancept, Doctrine: Basic Thinking i The United States Air Force. vol. 1 1O7-IMO W( Maxwell AFB, Ala.: Air University Press, 1989...Futrell, Ideas, Concepts, Doctrine: Basic Thinking in the United States Air Force, vol. 2, 1961-1984 ( Maxwell AFB, Ala.: Air University Press, 1989...in Vietnam and Why. Maxwell AFB, Ala: Air University Press, 1991. Warden, Col John A. HI. The Air Campaign - Planning For Combat. Washington, D.C
Improving Energy Security for Air Force Installations
2015-09-01
Wind power is a mature technology, with wind turbines first being used for electricity in the late 19th century. The Air Force operates two wind ...company, and the military unit receives energy credits back on its bill. Two concepts are important when considering the turbine size for a wind ...generation and consumption must remain balanced for a grid, so wind turbines are rarely used as a sole energy source since power is only generated
AIRCRAFT MAINTENANCE ENABLED JOINT CONCEPT FOR ENTRY OPERATIONS
2017-04-06
approach to manpower consolidation on a scale similar to what Rivet Workforce accomplished in the 1980s and 1990s. A consolidation based on aircraft...Logistics for the AirSea Battle,” Research (Maxwell Air Force Base , Alabama: Air Force Fellows, March 2011), 19. 36 “The Aviationist » Rapid Raptor...USAF A Research Report Submitted to the Faculty In Partial Fulfillment of the Graduation Requirements Advisor: Col Daniel Runyon 6 April 2017
A Study and Model of Operating Level Financial Management Philosophy Under RMS.
The lack of financial management education has prevented base level managers from using PRIME data as intended. This study examines the Air Force...operating level financial management philosophy before and after PRIME and the environment of PRIME adoption. A model in the form of two case problems...with solutions is created to portray the financial management concepts under PRIME to help educate base level Air Force logistic managers. The model
The equivalence between dislocation pile-ups and cracks
NASA Technical Reports Server (NTRS)
Liu, H. W.; Gao, Q.
1990-01-01
Cracks and dislocation pile-ups are equivalent to each other. In this paper, the physical equivalence between cracks and pile-ups is delineated, and the relationshps between crack-extension force, force on the leading dislocation, stress-intensity factor, and dislocation density are reviewed and summarized. These relations make it possible to extend quantitatively the recent advances in the concepts and practices of fracture mechanics to the studies of microfractures and microplastic deformations.
Canadian Forces in Joint Fires Support - Human Factors Analysis: Coalition Operations
2010-08-01
mesure/l’estimation des dommages collatéraux (EDC). Outil pour comprendre l’EDC de certains pays comparativement à celle des membres de l’OTAN et...Program (TDP). The TDP is aimed at concept development, evaluation for force design , and the demonstration of technologies fostered by Defence Research...logistics and the designation of targets on the joint targeting list. • Tactical capability / response time / training. The tactical capability of a fire
Military Innovation in the Rise and Fall of Great Powers: Lessons for America
2011-06-01
must institute forcing mechanisms to integrate the elements of national power toward this stated goal. Several of the forcing mechanisms proposed...about my thesis topic. CAPT Porter immediately took an interest in my ideas and gave me food for thought and book recommendations that shaped the...fighting mechanism . The inventive and martial nature of the Assyrian Empire allowed its people to develop, relatively quickly, the first concept of
OPALS on the ISS Artist Concept
2014-07-24
This artist rendition shows the Optical PAyload for Lasercomm Science OPALS operating from the International Space Station. OPALS was launched to the station from Cape Canaveral Air Force Station in Florida on April 18, 2014.
Information Dominance: Special Operations Forces in MOOTW.
1997-04-15
threats to our national security. In a rapidly changing world, S0F must be affordable yet technologically advanced to fully support emerging operational concepts and achieve critical information dominance for America in MOOTW.
Fastening hardware to honeycomb panels
NASA Technical Reports Server (NTRS)
Kenger, A.
1979-01-01
Adhesive bonding reduces likelihood of skin failure due to excessive forces or torques by utilizing an adhesive to honeycomb skin. Concept is useful in other applications of composites such as aircraft, automobiles, and home appliances.
Purple or Colorless--Which Way Up? An Entertaining Solubility Demonstration.
ERIC Educational Resources Information Center
Kitson, Trevor M.
2003-01-01
Presents an experiment that is quick and easy to prepare, visually striking, and amusing to students. Relates to several key chemical concepts including polarity, intermolecular forces, solubility, and spectrophotometry. (Author/NB)
2015-02-17
this study, course exams were used to measure student learning rather than research -based concept tests like the Force Concept Inventory [ 19), the...Release Information: This art icles has been accepted by Physical Review Special Topics -- Physics Education Research fo r publication. Previous...portraying official policy. II signed // MONTE D. ANDERSON, Lt Col, USAF Deputy Department Head for Research Department of Physics Tabs 1
Evaluation of Alternatives for an Army Precision Landing System.
1985-09-01
U FL - ! - Vv3- LN1.N V"VVu V- - - UW Vr - V V 416 -60 ,.1 :0 4 - L DG6 -46. 0- Iii V34 0 c 0.- to C aIa a id4 C13 a ’hO. i 410 Id...USAAVNC CPT E. Veiga . Concepts and Studies Division CPT R. Wilson. Concepts Branch CPT R. Roberts. USAATCA Liaison CPT Flynn, Force Structures
NASA Technical Reports Server (NTRS)
Wesselski, C. J.; Drexel, R. E.
1972-01-01
Load attenuators for the Apollo spacecraft crew couch and its potential applications are described. Energy absorption is achieved through friction and cyclic deformation of material. In one concept, energy absorption is accomplished by rolling a compressed ring of metal between two surfaces. In another concept, energy is absorbed by forcing a plastically deformed washer along a rod. Among the design problems that had to be solved were material selection, fatigue life, ring slippage, lubrication, and friction loading.
2008-08-18
Operations Concept Rules of engagement Reconnaissance, surveillance, and target acquisition Subject matter experts Technology readiness level Tactics...might call for the notification of an additional ASW platform, a pouncer, to reacquire, follow, and/or kill the transiter depending on the rules of...Naval Research Laboratory (E. Franchi , F. Erskine) 2 Naval Sea Systems Command (PEO-C4I and Space - D. Bauman, PEO-IWS - Technical Director, PEO-IWS5
Inverting the Army Intelligence Pyramid
2011-05-19
Intelligence for Counterinsurgency," Military Review 86, no. 5 (2006): 25. U.S. Army forces adapted well over the past nine years of the conflict and have...David H. Petraeus, "COMISAF’s Counterinsurgency Guidance,"(2010); Brian Burton and John Nagl, "Learning as We Go: The US Army Adapts to... adaptive and evolving enemies it faced by introducing the concept of “Every Soldier a Sensor.” With this concept, the Army sought to inculcate
Computerized Vocational Guidance (CVG) Systems: Evaluation for Use in Military Recruiting.
1984-02-01
how to relate the two, and how to explore, project, and choose. Whether Rogerian or more directive in nature, the essential counseling ingredient is to...Conference, Princeton, NJ: Educational Testing Service, 1974, 43-69. Katz, M. R., & Shatkin, L. Computer-assisted guidance: Concepts and practices (Res. Rep...Canadian Forces Personnel Applied Research Unit, 1980. Katz, M. R., & Shatkin, L. Computer-assisted guidance: Concepts and practices (Res. Rep. RR-80-1
In Service to the Nation: Air Force Research Institute Strategic Concept for 2018-2023
2009-01-01
must integrate at every level of operational planning and execution. The key to successful strategic communication lies in understanding that de ...Institute strategic concept for 2018–2023 / John A. Shaud. p. ; cm. Includes bibliographical references. ISBN 978-1-58566-189-3 1. Military planning ...United States. 2. United States—Air Force—Forecasting. 3. Strategic plan - ning—United States—Military aspects. 4. United States—Air Force—Operational
Haptic device development based on electro static force of cellulose electro active paper
NASA Astrophysics Data System (ADS)
Yun, Gyu-young; Kim, Sang-Youn; Jang, Sang-Dong; Kim, Dong-Gu; Kim, Jaehwan
2011-04-01
Haptic is one of well-considered device which is suitable for demanding virtual reality applications such as medical equipment, mobile devices, the online marketing and so on. Nowadays, many of concepts for haptic devices have been suggested to meet the demand of industries. Cellulose has received much attention as an emerging smart material, named as electro-active paper (EAPap). The EAPap is attractive for mobile haptic devices due to its unique characteristics in terms of low actuation power, suitability for thin devices and transparency. In this paper, we suggest a new concept of haptic actuator with the use of cellulose EAPap. Its performance is evaluated depending on various actuation conditions. As a result, cellulose electrostatic force actuator shows a large output displacement and fast response, which is suitable for mobile haptic devices.
[Percutaneously implantable aortic valve: the JenaValve concept evolution].
Figulla, Hans R; Ferrari, Markus
2006-10-01
Due to the increasing incidence of severe aortic stenosis in old and multimorbid patients, the percutaneous implantation of aortic valve-carrying stents has become an alternative to the surgical replacement of aortic valves. Starting in 1995, the authors developed a self-expanding stent which transferred the necessary forces for anchoring up to the aorta ascendens-a conception taken over from CoreValve. The further improvement of this idea over the past 11 years has led to a self-expanding, relatively short stent-valve system that is reliably positioned in the cusps of the old aortic valve and holds the old valve like a paper clip, thus transferring the holding forces physiologically. As compared to conventional systems, the sophisticated insertion catheter requires further chronic animal tests so as to represent a true alternative to the conventional surgical procedure.
Flexible Force Field Parameterization through Fitting on the Ab Initio-Derived Elastic Tensor
2017-01-01
Constructing functional forms and their corresponding force field parameters for the metal–linker interface of metal–organic frameworks is challenging. We propose fitting these parameters on the elastic tensor, computed from ab initio density functional theory calculations. The advantage of this top-down approach is that it becomes evident if functional forms are missing when components of the elastic tensor are off. As a proof-of-concept, a new flexible force field for MIL-47(V) is derived. Negative thermal expansion is observed and framework flexibility has a negligible effect on adsorption and transport properties for small guest molecules. We believe that this force field parametrization approach can serve as a useful tool for developing accurate flexible force field models that capture the correct mechanical behavior of the full periodic structure. PMID:28661672
Duality of force laws and conformal transformations
NASA Astrophysics Data System (ADS)
Kothawala, Dawood
2011-06-01
As was first noted by Isaac Newton, the two most famous ellipses of classical mechanics, arising from the force laws F ∝r and F ∝1/r2, can be mapped onto each other by changing the location of the center of force. Less well known is that this mapping can also be achieved by the complex transformation, z →z2. We derive this result and its generalization by writing the Gaussian curvature in its covariant form, and then changing the metric by a conformal transformation which mimics this mapping of the curves. We indicate how the conserved Laplace-Runge-Lenz vector for the 1/r2 force law transforms under this transformation, and compare it with the corresponding quantities for the linear force law. Our main aim is to present this duality by introducing concepts from differential geometry.
Li, Bo; Cheng, Xiaoliang; Zhang, Zhengfang
2013-01-01
In an implicit-solvent description of molecular solvation, the electrostatic free energy is given through the electrostatic potential. This potential solves a boundary-value problem of the Poisson–Boltzmann equation in which the dielectric coefficient changes across the solute-solvent interface—the dielectric boundary. The dielectric boundary force acting on such a boundary is the negative first variation of the electrostatic free energy with respect to the location change of the boundary. In this work, the concept of shape derivative is used to define such variations and formulas of the dielectric boundary force are derived. It is shown that such a force is always in the direction toward the charged solute molecules. PMID:24058212
Microfabricated magnetic traps for single molecule manipulation and measurement
NASA Astrophysics Data System (ADS)
Mirowski, Elizabeth; Moreland, John; Russek, Stephen; Donahue, Michael
2003-03-01
We have microfabricated patterned magnetic thin film traps for capturing superparamagnetic beads in microfluidic cells. The traps are based on a novel concept of using a magnetic force microsope cantilever for transporting magnetic beads from one trap to another along the surface of a thin silicon nitride membrane. We specifically address the optimal design criteria for the traps. In addition, we present measurements of the forces on a bead (attached to a functionalized cantilever tip) as a function of its position near the trap. Equivalent spring constants of various trap geometries are extrapolated from the force measurements. The force measurements will be compared to micromagnetic modelling of the system as well as the Brownian motion of the bead in the trap.
Probing students’ conceptions at the classical-quantum interface
NASA Astrophysics Data System (ADS)
Chhabra, Mahima; Das, Ritwick
2018-03-01
Quantum mechanics (QM) is one of the core subject areas in the undergraduate physics curriculum and many of the advanced level physics courses involve direct or indirect application of the concepts and ideas taught in QM. On the other hand, proper understanding of QM interpretations requires an optimum level of understanding of fundamental concepts in classical physics such as energy, momentum, force and their role in determining motion of the particle. This study is an attempt to explore a group of undergraduate students’ mental models regarding fundamental concepts in classical physics which are actually the stepping stone for understanding and visualisation of QM. The data and analysis presented here elucidate the challenges students face to understand the classical ideas and how that affects their understanding of QM.
Applications of a new mass-driver concept
NASA Technical Reports Server (NTRS)
Oneill, G. K.
1981-01-01
A description of the operating principles and requirements of a novel mass-driver concept is presented. The design obtains acceleration of payload bucket coils by means of transverse focussing from strong, off-axis restoring forces that are produced by drive coils operating in a 'pull-only' mode. The concept offers the unprecedented possibility of operating high-performance mass-drivers entirely within the limitations of existing commercial switching devices, such as silicon-controlled rectifiers, spark gaps, vacuum-triggered arcs or vacuum mechanical switches. Representative applications of the concept described are: (1) a large-diameter magnetic lunar launcher for payloads having autonomous maneuvering; (2) an intermediate-diameter launcher with long operational life; and (3) a reaction engine for orbit transfer of large, massive objects.
Adhesion switch on a gecko-foot inspired smart nanocupule surface
NASA Astrophysics Data System (ADS)
Song, Wenlong
2014-10-01
A gecko-foot inspired nanocupule surface prepared by an AAO template covering method was composed of poly(N-isopropylacrylamide) and polystyrene blend. Both superhydrophobicity and high adhesion force were exhibited on the PNIPAm/PS film at room temperature. Moreover, by controlling the temperature, the wettability of the film could be switched between 138.1 +/- 5.5° and 150.6 +/- 1.5°, and the adhesion force could also be correspondingly tuned accurately by temperature. This reversibility in both wettability and adhesion force could be used to construct smart devices for fine selection of water droplets. The proof-of-concept was demonstrated by the selective catching of precise weight controlled water droplets at different temperatures. This work could help us to design new type of devices for blood bioanalysis or lossless drug transportation.A gecko-foot inspired nanocupule surface prepared by an AAO template covering method was composed of poly(N-isopropylacrylamide) and polystyrene blend. Both superhydrophobicity and high adhesion force were exhibited on the PNIPAm/PS film at room temperature. Moreover, by controlling the temperature, the wettability of the film could be switched between 138.1 +/- 5.5° and 150.6 +/- 1.5°, and the adhesion force could also be correspondingly tuned accurately by temperature. This reversibility in both wettability and adhesion force could be used to construct smart devices for fine selection of water droplets. The proof-of-concept was demonstrated by the selective catching of precise weight controlled water droplets at different temperatures. This work could help us to design new type of devices for blood bioanalysis or lossless drug transportation. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr04090b
Uniform circular motion concept attainment through circle share learning model using real media
NASA Astrophysics Data System (ADS)
Ponimin; Suparmi; Sarwanto; Sunarno, W.
2017-01-01
Uniform circular motion is an important concept and has many applications in life. Student’s concept understanding of uniform circular motion is not optimal because the teaching learning is not carried out properly in accordance with the characteristics of the concept. To improve student learning outcomes required better teaching learning which is match with the characteristics of uniform circular motion. The purpose of the study is to determine the effect of real media and circle share model to the understanding of the uniform circular motion concept. The real media was used to visualize of uniform circular motion concept. The real media consists of toy car, round table and spring balance. Circle share model is a learning model through discussion sequentially and programmed. Each group must evaluate the worksheets of another group in a circular position. The first group evaluates worksheets the second group, the second group evaluates worksheets third group, and the end group evaluates the worksheets of the first group. Assessment of learning outcomes includes experiment worksheets and post-test of students. Based on data analysis we obtained some findings. First, students can explain the understanding of uniform circular motion whose angular velocity and speed is constant correctly. Second, students can distinguish the angular velocity and linear velocity correctly. Third, students can explain the direction of the linear velocity vector and the direction of the centripetal force vector. Fourth, the student can explain the influence of the mass, radius, and velocity toward the centripetal force. Fifth, students can explain the principle of combined of wheels. Sixth, teaching learning used circle share, can increase student activity, experimental results and efficiency of discussion time.
Acoustic radiation force control: Pulsating spherical carriers.
Rajabi, Majid; Mojahed, Alireza
2018-02-01
The interaction between harmonic plane progressive acoustic beams and a pulsating spherical radiator is studied. The acoustic radiation force function exerted on the spherical body is derived as a function of the incident wave pressure and the monopole vibration characteristics (i.e., amplitude and phase) of the body. Two distinct strategies are presented in order to alter the radiation force effects (i.e., pushing and pulling states) by changing its magnitude and direction. In the first strategy, an incident wave field with known amplitude and phase is considered. It is analytically shown that the zero- radiation force state (i.e., radiation force function cancellation) is achievable for specific pulsation characteristics belong to a frequency-dependent straight line equation in the plane of real-imaginary components (i.e., Nyquist Plane) of prescribed surface displacement. It is illustrated that these characteristic lines divide the mentioned displacement plane into two regions of positive (i.e., pushing) and negative (i.e., pulling) radiation forces. In the second strategy, the zero, negative and positive states of radiation force are obtained through adjusting the incident wave field characteristics (i.e., amplitude and phase) which insonifies the radiator with prescribed pulsation characteristics. It is proved that zero radiation force state occurs for incident wave pressure characteristics belong to specific frequency-dependent circles in Nyquist plane of incident wave pressure. These characteristic circles divide the Nyquist plane into two distinct regions corresponding to positive (out of circles) and negative (in the circles) values of radiation force function. It is analytically shown that the maximum amplitude of negative radiation force is exactly equal to the amplitude of the (positive) radiation force exerted upon the sphere in the passive state, by the same incident field. The developed concepts are much more deepened by considering the required power supply for distinct cases of zero, negative and positive radiation force states along with the frequency dependent asymmetry index. In addition, considering the effect of phase difference between the incident wave field and the pulsating object, and its possible variation with respect to spatial position of object, some practical points about the spatial average of generated radiation force, the optimal state of operation, the stability of zero radiation force states and the possibly of precise motion control are discussed. This work would extend the novel concept of smart carriers to and may be helpful for robust single-beam acoustic handling techniques. Furthermore, the shown capability of precise motion control may be considered as a new way toward smart acoustic driven micro-mechanisms and micro-machines. Copyright © 2017 Elsevier B.V. All rights reserved.
Harada, Shingo; Kanao, Kenichiro; Yamamoto, Yuki; Arie, Takayuki; Akita, Seiji; Takei, Kuniharu
2014-12-23
A three-axis tactile force sensor that determines the touch and slip/friction force may advance artificial skin and robotic applications by fully imitating human skin. The ability to detect slip/friction and tactile forces simultaneously allows unknown objects to be held in robotic applications. However, the functionalities of flexible devices have been limited to a tactile force in one direction due to difficulties fabricating devices on flexible substrates. Here we demonstrate a fully printed fingerprint-like three-axis tactile force and temperature sensor for artificial skin applications. To achieve economic macroscale devices, these sensors are fabricated and integrated using only printing methods. Strain engineering enables the strain distribution to be detected upon applying a slip/friction force. By reading the strain difference at four integrated force sensors for a pixel, both the tactile and slip/friction forces can be analyzed simultaneously. As a proof of concept, the high sensitivity and selectivity for both force and temperature are demonstrated using a 3×3 array artificial skin that senses tactile, slip/friction, and temperature. Multifunctional sensing components for a flexible device are important advances for both practical applications and basic research in flexible electronics.
NASA Astrophysics Data System (ADS)
Kang, Jee Sun Emily
This study explored how inquiry-based teaching and learning processes occurred in two teachers' diverse 8th grade Physical Science classrooms in a Program Improvement junior high school within the context of high-stakes standardized testing. Instructors for the courses examined included not only the two 8th grade science teachers, but also graduate fellows from a nearby university. Research was drawn from inquiry-based instruction in science education, the achievement gap, and the high stakes testing movement, as well as situated learning theory to understand how opportunities for inquiry were negotiated within the diverse classroom context. Transcripts of taped class sessions; student work samples; interviews of teachers and students; and scores from the California Standards Test in science were collected and analyzed. Findings indicated that the teachers provided structured inquiry in order to support their students in learning about forces and to prepare them for the standardized test. Teachers also supported students in generating evidence-based explanations, connecting inquiry-based investigations with content on forces, proficiently using science vocabulary, and connecting concepts about forces to their daily lives. Findings from classroom data revealed constraints to student learning: students' limited language proficiency, peer counter culture, and limited time. Supports were evidenced as well: graduate fellows' support during investigations, teachers' guided questioning, standardized test preparation, literacy support, and home-school connections. There was no statistical difference in achievement on the Forces Unit test or science standardized test between classes with graduate fellows and without fellows. There was also no statistical difference in student performance between the two teachers' classrooms, even though their teaching styles were very different. However, there was a strong correlation between students' achievement on the chapter test and their achievement on the Forces portion of the CST. Students' English language proficiency and socioeconomic status were also strongly correlated with their achievement on the standardized test. Notwithstanding the constraints of standardized testing, the teachers had students practice the heart of inquiry -- to connect evidence with explanations and process with content. Engaging in inquiry-based instruction provided a context for students, even English language learners, to demonstrate their knowledge of forces. Students had stronger and more detailed ideas about concepts when they engaged in activities that were tightly connected to the concepts, as well as to their lives and experiences.
Students' Concepts of Force: The Importance of Understanding Newton's Third Law.
ERIC Educational Resources Information Center
Brown, David E.
1989-01-01
Reports various misconceptions of Newton's third law obtained from interviews and written tests of high school students. Suggests putting emphasis on the third law in physics teaching. Ten references are listed. (YP)
Teaching about Consumer Law: Activities for the Classroom.
ERIC Educational Resources Information Center
Bjorklun, Eugene C.
1989-01-01
Reiterating that students have become a potent market force, explains how teachers can introduce the concept of consumer law. Gives three examples of hypothetical situations in which contracts, warranties, and ethics are discussed. (GG)
ERIC Educational Resources Information Center
Anthony, Joan L.
1994-01-01
Describes an activity where teams of parents and children work together to solve problems involving matchbox-sized race cars. The teams collect, record, and analyze data; measure distances in metric; and explore concepts related to mass, friction, and force. (PR)
Joint Chiefs of Staff > Directorates > J3 | Operations
Joint Staff Structure Joint Staff Inspector General Origin of Joint Concepts U.S. Code | Joint Chiefs of J8 | Force Structure, Resources & Assessment Contact J3 Operations Home : Directorates : J3
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chandrasekhar Potluri,; Madhavi Anugolu; Marco P. Schoen
2013-08-01
In this work, an array of three surface Electrography (sEMG) sensors are used to acquired muscle extension and contraction signals for 18 healthy test subjects. The skeletal muscle force is estimated using the acquired sEMG signals and a Non-linear Wiener Hammerstein model, relating the two signals in a dynamic fashion. The model is obtained from using System Identification (SI) algorithm. The obtained force models for each sensor are fused using a proposed fuzzy logic concept with the intent to improve the force estimation accuracy and resilience to sensor failure or misalignment. For the fuzzy logic inference system, the sEMG entropy,more » the relative error, and the correlation of the force signals are considered for defining the membership functions. The proposed fusion algorithm yields an average of 92.49% correlation between the actual force and the overall estimated force output. In addition, the proposed fusionbased approach is implemented on a test platform. Experiments indicate an improvement in finger/hand force estimation.« less
Unsteady force estimation using a Lagrangian drift-volume approach
NASA Astrophysics Data System (ADS)
McPhaden, Cameron J.; Rival, David E.
2018-04-01
A novel Lagrangian force estimation technique for unsteady fluid flows has been developed, using the concept of a Darwinian drift volume to measure unsteady forces on accelerating bodies. The construct of added mass in viscous flows, calculated from a series of drift volumes, is used to calculate the reaction force on an accelerating circular flat plate, containing highly-separated, vortical flow. The net displacement of fluid contained within the drift volumes is, through Darwin's drift-volume added-mass proposition, equal to the added mass of the plate and provides the reaction force of the fluid on the body. The resultant unsteady force estimates from the proposed technique are shown to align with the measured drag force associated with a rapid acceleration. The critical aspects of understanding unsteady flows, relating to peak and time-resolved forces, often lie within the acceleration phase of the motions, which are well-captured by the drift-volume approach. Therefore, this Lagrangian added-mass estimation technique opens the door to fluid-dynamic analyses in areas that, until now, were inaccessible by conventional means.
Clinical Evidence for the Relationship between Nail Configuration and Mechanical Forces
Ogawa, Rei
2014-01-01
Summary: Mechanobiology is an emerging field of science that focuses on the way physical forces and changes in cell or tissue mechanics contribute to development, physiology, and disease. As nails are always exposed to physical stimulation, mechanical forces may have a particularly pronounced effect on nail configuration and could be involved in the development of nail deformities. However, the role of mechanobiology in nail configuration and deformities has rarely been assessed. This review describes what is currently understood regarding the effect of mechanical force on nail configuration and deformities. On the basis of these observations, we hypothesize that nails have an automatic curvature function that allows them to adapt to the daily upward mechanical forces. Under normal conditions, the upward daily mechanical force and the automatic curvature force are well balanced. However, an imbalance between these 2 forces may cause nail deformation. For example, pincer nails may be caused by the absence of upward mechanical forces or a genetic propensity increase in the automatic curvature force, whereas koilonychias may occur when the upward mechanical force exceeds the automatic curvature force, thereby causing the nail to curve outward. This hypothesis is a new concept that could aid the development of innovative methods to prevent and treat nail deformities. PMID:25289309
Setting Priorities in the Age of Austerity: British, French, and German Experiences
2013-01-01
the cuts had not gone far enough, but that the scale of the necessary reductions made it impossible to get away with simply trimming the existing...2020, House of Commons Library, Standard Note 06396, July 26, 2012, pp. 27–28. 9 scale . For example, the 2008 “Future Land Operational Concept...paper called for maintaining broad capabilities: Land forces will need to project suitably configured, scaled and trained forces at appropriate
Ideas as Institutions: Explaining the Air Force’s Struggle With Its Aerospace Concept
2006-04-01
12 See Rebecca Grant, “Is the Spaceplane Dead?” Air Force 84, no. 11 (November 2001): 68-72; and Thomas A . Heppenheimer , “Origins of Hypersonic...and Diplomacy, May 1994. 391 Heppenheimer , Thomas A . “Origins of Hypersonic Propulsion: A Personal History.” Air Power History 47, no. 3...English derivation of a definition proposed by sociologists Peter L. Berger and Thomas Luckmann. In their book, The Social Construction of Reality: A
Space Station Program implications from the viewpoint of the Space Station Operations Task Force
NASA Technical Reports Server (NTRS)
Paules, Granville E.; Lyman, Peter; Shelley, Carl B.
1987-01-01
An operational concept for the Space Station which has been developed by the Space Station Operations Task Force is described. The operations functions are described, and the relationships of these functions to the overall framework for operations are defined. Product flows for the recommended framework are discussed, and the roles and responsibilities for the proposed operations organization during both the development and the mature operations phases of the Space Station Program are examined.
Logistics and Maintenance Concepts for a Future Naval Force
2001-12-01
Co - opetition . Currency-Doubleday. Retrieved December 10, 2001 from...Navigation CND Can Not Duplicate CO Commanding Officer COMNAVAIRLANT Commander Naval Forces Atlantic COSAL Consolidated Ship Allowance List CPO...ra ul ic s C or ro si on , O pe ra tio na l f lig ht co nt ro ls de gr ad at io n W id es pr ea d W ir e D am ag e X X X X X X X X
Space station operations task force. Panel 3 report: User development and integration
NASA Technical Reports Server (NTRS)
1987-01-01
The User Development and Integration Panel of the Space Station Operations Task Force was chartered to develop concepts relating to the operations of the Space Station manned base and the platforms, user accommodation and integration activities. The needs of the user community are addressed in the context with the mature operations phase of the Space Station. Issues addressed include space station pricing options, marketing strategies, payload selection and resource allocation options, and manifesting techniques.
Cleared Hot: A Forward Air Control (Airborne) Concepts Trainer
2006-09-01
list of high-level objectives imitating a detailed requirements document. In those cases, software developers are forced to make best guesses about...software developers are forced to make best guesses about how to meet those objectives. Is there a better method? We embarked on a project to create a...with participants at the end of an 18-month development cycle, we did the next best thing: Cleared Hot was taken to the mission subject matter
2017-03-01
Executive Summary is a product of the Defense Science Board (DSB). The DSB is a Federal Advisory Committee established to provide independent advice to the...Executive Summary Since 2000, when the Defense Science Board concluded space superiority was absolutely essential in achieving global awareness, information...control, critical enabling doctrine, and policy concepts. From April 2015 through September 2016, the Task Force received more than 40 briefings from
ERIC Educational Resources Information Center
Texas Education Agency, Austin.
This summary highlights implementation strategies from the full report for restructuring middle grade education in Texas. The task force was guided by a central theme--a vision of Texas schools using each other as resources and the campus planning process as a vehicle for implementing research-based concepts and practices in the middle grades.…
Precision Engagement at the Strategic Level of War: Guiding Promise or Wishful Thinking?
2001-04-01
and do not reflect the official policy or position of the US government or the Department of Defense. In accordance with Air Force Instruction 51...graciously including me in on division social activities. Most of all, I thank my wife Diane. Despite being a full-time mom to our twelve-, nine...principles, policies and concepts into an integrated system for the purpose of governing all components of a military force in combat, and assuring
On the manipulability of dual cooperative robots
NASA Technical Reports Server (NTRS)
Chiacchio, P.; Chiaverini, S.; Sciavicco, L.; Siciliano, B.
1989-01-01
The definition of manipulability ellipsoids for dual robot systems is given. A suitable kineto-static formulation for dual cooperative robots is adopted which allows for a global task space description of external and internal forces, and relative velocities. The well known concepts of force and velocity manipulability ellipsoids for a single robot are formally extended and the contributions of the two single robots to the cooperative system ellipsoids are illustrated. Duality properties are discussed. A practical case study is developed.
1974-04-01
A Jh .*H-M,fcflTlt FUTURE TERMINAL AIR TRAFFIC MANAGEMENT CONCEPTS John G. Kreifeldt Department of Engineering Design Tufts University,Medford...wright-patterson afb,ohio Hair force institute of technology > air force flight dynamics laboratory 1 V& t \\ jfr£ Approved for public release...report should not be returned unless return is required by security considerationsi contractual obligations, or notice on a specific document. AIR
The Validity of Conventional Assumptions Concerning Flexible Response
1989-01-01
could hold until reinforcements arrive. A Soviet attack on NATO would be met by a NATO covering force, consisting largely of armoured cavalry forma...inter- diction of the follow-on forces. Air Defense Under [.resent NATO operational concepts, most aircraft capa- ble of fighting alr-to-air will be...existing Nike and Hercules units by 1990--two years early to save money. The result is critical gaps in defense of English Channel ports. (29:36) Follow-on
Bolster Ground Force Capabilities in the Asia-Pacific Region
2016-05-12
territory in Asia. As Sun Tzu stated, “Thus, what is of supreme importance in war is to attack the enemy’s strategy.” 25 Bolstered USPACOM ground force...THOUGHTS As Sun Tzu observed, the pinnacle of military strategy is to subdue the enemy and win without fighting. 54 China appears to be applying...Concept, Offshore Control, and Deterrence by Denial,” 40. 25. Sun Tzu , Art of War, trans. Samuel B. Griffith (Oxford, UK: Oxford University Press
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rayski, J.
1959-01-01
A conception of a six-dimensional world enables a geometrical interpretation of the electric charge, charge c onjugation, gauge transformations, and of the electromagnetic field. The same conception explains satisfactorily the isospin, its cornection with the electric charge, and the ps- scalar character of nuclear forces. Several qualitative and some quantitative properties of strongly interacting particles (strangeness, rest masses, etc.) find an intuitive explanation within this geometrical framework. (auth)
The optimization of force inputs for active structural acoustic control using a neural network
NASA Technical Reports Server (NTRS)
Cabell, R. H.; Lester, H. C.; Silcox, R. J.
1992-01-01
This paper investigates the use of a neural network to determine which force actuators, of a multi-actuator array, are best activated in order to achieve structural-acoustic control. The concept is demonstrated using a cylinder/cavity model on which the control forces, produced by piezoelectric actuators, are applied with the objective of reducing the interior noise. A two-layer neural network is employed and the back propagation solution is compared with the results calculated by a conventional, least-squares optimization analysis. The ability of the neural network to accurately and efficiently control actuator activation for interior noise reduction is demonstrated.
From Conception to Birth: The Forces Responsible for AFCyber’s Evolution
2014-06-01
matter how good or bad my days were – and I experienced a fair number of both during the 11-month course – she provided a shoulder to cry on, a...Robert J. Lamb , “Joint Task Force for Computer Network Defense,” IA Newsletter, Winter 98/99, Vol 2, No. 3, http://www.iwar.org.uk/infocon/dtic‐ia...Future of Warfare.” Real Clear Defense, 24 February 2014. Lamb , Robert J. “Joint Task Force for Computer Network Defense.” IA Newsletter, Winter 98
Teaching weight to explicitly address language ambiguities and conceptual difficulties
NASA Astrophysics Data System (ADS)
Taibu, Rex; Schuster, David; Rudge, David
2017-06-01
Language ambiguities in concept meanings can exacerbate student learning difficulties and conceptual understanding of physics concepts. This is especially true for the concept of "weight," which has multiple meanings in both scientific and everyday usage. The term weight has been defined in several different ways, with nuances, but in textbooks and teaching the term is almost always defined in one of two ways: operationally either as the contact force between an object and a measuring scale or as the gravitational force on an object due to some other body such as Earth. The use of the same name for different concepts leads to much confusion, especially in accelerating situations, and to conflicting notions of "weightlessness" in free fall situations. In the present paper, we share an innovative approach that initially avoids the term weight entirely while teaching the physics of each situation, and then teaches the language ambiguities explicitly. We developed an instructional module with this approach and implemented it over two terms in three sections of an introductory physics course for preservice elementary teachers. Learning gains for content understanding were assessed using pretests and post-tests. Participants achieved remarkably high gains for both static and accelerating situations. Surveys pre- and postinstruction showed substantially improved appreciation of language issues and ambiguities associated with weight, weightlessness, and free fall. Interviews with instructors teaching the module provided additional insight into the advantages and teaching demands of the new approach.
NASA Astrophysics Data System (ADS)
von Hippel, Matthew Hans Benjamin
A novel vehicle concept is introduced and its feasibility as an autonomous, self-propelled weather buoy for use in violent storm systems is analyzed. The vehicle concept is a spar sailboat -- consisting of only a deep keel and a sailing rig; no hull -- a design which is intended to improve longevity in rough seas as well as provide ideal placement opportunities for meteorological sensors. To evaluate the hypothetical locomotive and meteorological observation capabilities of the concept sailing spar in hurricane-like conditions, several relevant oceanographic phenomena are analyzed with the performance of the concept vehicle in mind. Enthalpy transfer from the ocean to the air is noted as the primary driving force of tropical storms and therefore becomes the measuring objective of the sailing spar. A discrete, iterative process for optimizing driving force while achieving equilibrium between the four airfoil surfaces is used to steer the sailing spar towards any objective despite variable and opposing simulated winds. Based on the limitations of sailing theory, logic is developed to autonomously navigate the sailing spar between human-selected waypoints on a digitized geographic map. Due the perceived inability to measure air-sea enthalpy exchange because the nature of tropical storms and due to its small scale, the sailing spar is deemed infeasible as a hurricane-capable meteorological observation platform.
Primary care in a new era: disillusion and dissolution?.
Sandy, Lewis G; Schroeder, Steven A
2003-02-04
The current dilemmas in primary care stem from 1) the unintended consequences of forces thought to promote primary care and 2) the "disruptive technologies of care" that attack the very function and concept of primary care itself. This paper suggests that these forces, in combination with "tiering" in the health insurance market, could lead to the dissolution of primary care as a single concept, to be replaced by alignment of clinicians by economic niche. Evidence already exists in the marketplace for both tiering of health insurance benefits and corresponding practice changes within primary care. In the future, primary care for the top tier will cater to the affluent as "full-service brokers" and will be delivered by a wide variety of clinicians. The middle tier will continue to grapple with tensions created by patient demand and bureaucratic systems but will remain most closely aligned to primary care as a concept. The lower tier will become increasingly concerned with community health and social justice. Each primary care specialty will adapt in a unique way to a tiered world, with general internal medicine facing the most challenges. Given this forecast for the future, those concerned about primary care should focus less on workforce issues and more on macro health care financing and organization issues (such as Medicare reform); appropriate training models; and the development of a conception of primary care that emphasizes values and ethos, not just function.
Material efficiency in a multi-material world.
Lifset, Reid; Eckelman, Matthew
2013-03-13
Material efficiency--using less of a material to make a product or supply a service--is gaining attention as a means for accomplishing important environmental goals. The ultimate goal of material efficiency is not to use less physical material but to reduce the impacts associated with its use. This article examines the concept and definition of material efficiency and argues that for it to be an effective strategy it must confront the challenges of operating in a multi-material world, providing guidance when materials are used together and when they compete. A series of conceptions of material efficiency are described, starting with mass-based formulations and expanding to consider multiple resources in the supply chain of a single material, and then to multiple resources in the supply chains of multiple materials used together, and further to multiple environmental impacts. The conception of material efficiency is further broadened by considering material choice, exploring the technical and economic effects both of using less material and of materials competition. Finally, this entire materials-based techno-economic system is considered with respect to the impact of complex policies and political forces. The overall goal here is to show how the concept of material efficiency when faced with more expansive--and yet directly relevant--definitional boundaries is forced to confront analytical challenges that are both familiar and difficult in life cycle assessment and product-based approaches.
Virtual Organizations: An Overview
NASA Astrophysics Data System (ADS)
Nami, Mohammad Reza
The need to remain competitive in the open market forces companies to concentrate on their core competencies while searching for alliances when additional skills or resources are needed to fulfill business opportunities. The changing business situation of companies and customer needs have motivated researchers to introduce Virtual Organization (VO) idea. A Virtual Organization is always a form of partnership and managing partners and handling partnerships are crucial. Virtual organizations are defined as a temporary collection of enterprises that cooperate and share resources, knowledge, and competencies to better respond to business opportunities. This paper presents base concepts of virtual organizations including properties, management concepts, operational concepts, and main issues in collaboration such as security and authentication.
Hysteresis Bearingless Slice Motors with Homopolar Flux-biasing.
Noh, Minkyun; Gruber, Wolfgang; Trumper, David L
2017-10-01
We present a new concept of bearingless slice motor that levitates and rotates a ring-shaped solid rotor. The rotor is made of a semi-hard magnetic material exhibiting magnetic hysteresis, such as D2 steel. The rotor is radially biased with a homopolar permanent-magnetic flux, on which the stator can superimpose 2-pole flux to generate suspension forces. By regulating the suspension forces based on position feedback, the two radial rotor degrees of freedom are actively stabilized. The two tilting degrees of freedom and the axial translation are passively stable due to the reluctance forces from the bias flux. In addition, the stator can generate a torque by superimposing 6- pole rotating flux, which drags the rotor via hysteresis coupling. This 6-pole flux does not generate radial forces in conjunction with the homopolar flux or 2-pole flux, and therefore the suspension force generation is in principle decoupled from the driving torque generation. We have developed a prototype system as a proof of concept. The stator has twelve teeth, each of which has a single phase winding that is individually driven by a linear transconductance power amplifier. The system has four reflective-type optical sensors to differentially measure the two radial degrees of freedom of the rotor. The suspension control loop is implemented such that the phase margin is 25 degrees at the cross-over frequency of 110 Hz. The prototype system can levitate the rotor and drive it up to about 1730 rpm. The maximum driving torque is about 2.7 mNm.
NASA Technical Reports Server (NTRS)
Collins, Michelle (Editor); Mulenburg, Gerald
2002-01-01
The book entitled "Fusion Leadership: Unlocking the Subtle Forces that Change People and Organizations Richard L. Daft and Robert H. Lengel (1998) Berett-Koehler Publishers, Inc." was Reviewed by Dr. Michelle Collins, NASA Headquarters. If you've already read books on leadership and organizational change by authors such as Moshe Rubinstein and Iris Firstenberg, Peter Senge, Tom Peters, and Steven Covey, and you were thinking of rereading them, you don't have to do that now. Just read this book instead. It's a fusion of many of their same concepts presented from a different view. The book does not explore any particular subject in depth. Rather the authors "skim" many subjects and concepts, interlacing them to develop the concept of "Fusion Leadership". The fundamental concept of treating people as people rather than machines is the main theme. "Fusion Leadership" is the process of fusing people together by nurturing six "subtle" forces: mindfulness, courage, vision, heart, communication, and integrity. To do so, hierarchy is diminished and responsibility both for oneself as well as for the team is emphasized. There are a number of organizations and managers that will find such a change threatening. The concepts behind such a management style are straightforward and the benefits are intuitive once you've reflected on them; however, the obvious benefits of the behavioral change proposed in Fusion Leadership can be completely lost in a fear-based system. The concept of caring about people in one's organization was the common thread in Chris Turner's book All Hat, No Cattle (see book review, ASK 5). Much is being written about the re-humanizing of the workplace, but the basis of it is so common sense that one wonders what's taking so long for the workplace to change? Whether you're in a position to change your organization or simply your project team, you'll find the concepts in fusion leadership equally applicable.
Multi-Axis Force/Torque Sensor Based on Simply-Supported Beam and Optoelectronics.
Noh, Yohan; Bimbo, Joao; Sareh, Sina; Wurdemann, Helge; Fraś, Jan; Chathuranga, Damith Suresh; Liu, Hongbin; Housden, James; Althoefer, Kaspar; Rhode, Kawal
2016-11-17
This paper presents a multi-axis force/torque sensor based on simply-supported beam and optoelectronic technology. The sensor's main advantages are: (1) Low power consumption; (2) low-level noise in comparison with conventional methods of force sensing (e.g., using strain gauges); (3) the ability to be embedded into different mechanical structures; (4) miniaturisation; (5) simple manufacture and customisation to fit a wide-range of robot systems; and (6) low-cost fabrication and assembly of sensor structure. For these reasons, the proposed multi-axis force/torque sensor can be used in a wide range of application areas including medical robotics, manufacturing, and areas involving human-robot interaction. This paper shows the application of our concept of a force/torque sensor to flexible continuum manipulators: A cylindrical MIS (Minimally Invasive Surgery) robot, and includes its design, fabrication, and evaluation tests.
Collaborative engagement experiment
NASA Astrophysics Data System (ADS)
Mullens, Katherine; Troyer, Bradley; Wade, Robert; Skibba, Brian; Dunn, Michael
2006-05-01
Unmanned ground and air systems operating in collaboration have the potential to provide future Joint Forces a significant capability for operations in complex terrain. Collaborative Engagement Experiment (CEE) is a consolidation of separate Air Force, Army and Navy collaborative efforts within the Joint Robotics Program (JRP) to provide a picture of the future of unmanned warfare. The Air Force Research Laboratory (AFRL), Material and Manufacturing Directorate, Aerospace Expeditionary Force Division, Force Protection Branch (AFRL/MLQF), The Army Aviation and Missile Research, Development and Engineering Center (AMRDEC) Joint Technology Center (JTC)/Systems Integration Laboratory (SIL), and the Space and Naval Warfare Systems Center - San Diego (SSC San Diego) are conducting technical research and proof of principle experiments for an envisioned operational concept for extended range, three dimensional, collaborative operations between unmanned systems, with enhanced situational awareness for lethal operations in complex terrain. This paper describes the work by these organizations to date and outlines some of the plans for future work.
Experimental Demonstration of a Synthetic Lorentz Force by Using Radiation Pressure.
Šantić, N; Dubček, T; Aumiler, D; Buljan, H; Ban, T
2015-09-02
Synthetic magnetism in cold atomic gases opened the doors to many exciting novel physical systems and phenomena. Ubiquitous are the methods used for the creation of synthetic magnetic fields. They include rapidly rotating Bose-Einstein condensates employing the analogy between the Coriolis and the Lorentz force, and laser-atom interactions employing the analogy between the Berry phase and the Aharonov-Bohm phase. Interestingly, radiation pressure - being one of the most common forces induced by light - has not yet been used for synthetic magnetism. We experimentally demonstrate a synthetic Lorentz force, based on the radiation pressure and the Doppler effect, by observing the centre-of-mass motion of a cold atomic cloud. The force is perpendicular to the velocity of the cold atomic cloud, and zero for the cloud at rest. Our novel concept is straightforward to implement in a large volume, for a broad range of velocities, and can be extended to different geometries.
Multi-Axis Force/Torque Sensor Based on Simply-Supported Beam and Optoelectronics
Noh, Yohan; Bimbo, Joao; Sareh, Sina; Wurdemann, Helge; Fraś, Jan; Chathuranga, Damith Suresh; Liu, Hongbin; Housden, James; Althoefer, Kaspar; Rhode, Kawal
2016-01-01
This paper presents a multi-axis force/torque sensor based on simply-supported beam and optoelectronic technology. The sensor’s main advantages are: (1) Low power consumption; (2) low-level noise in comparison with conventional methods of force sensing (e.g., using strain gauges); (3) the ability to be embedded into different mechanical structures; (4) miniaturisation; (5) simple manufacture and customisation to fit a wide-range of robot systems; and (6) low-cost fabrication and assembly of sensor structure. For these reasons, the proposed multi-axis force/torque sensor can be used in a wide range of application areas including medical robotics, manufacturing, and areas involving human–robot interaction. This paper shows the application of our concept of a force/torque sensor to flexible continuum manipulators: A cylindrical MIS (Minimally Invasive Surgery) robot, and includes its design, fabrication, and evaluation tests. PMID:27869689
Design concept for pressure switch calibrator
NASA Technical Reports Server (NTRS)
Slingerland, M. G.
1966-01-01
Calibrator and switch design enables pressure switches to operate under 150 g shock loads. The design employs a saturated liquid-to-vapor phase transition at constant pressure to produce a known force independent of displacement over a usable range.
Chemical Principles Exemplified
ERIC Educational Resources Information Center
Plumb, Robert C.
1974-01-01
Describes bonding properties that account for the difference in toxicity between hydrogen cyanide and carbon monoxide. Uses the concepts of intermolecular and intramolecular forces in explaining the operation of pressure sensitive adhesives. Gives a definition of a cubic crystal class. (GS)
Mechanical solar motor: A concept
NASA Technical Reports Server (NTRS)
Hein, L. A.; Myers, W. N.
1975-01-01
Motor is proposed to convert radiation from sun directly into mechanical energy. Motor utilizes thermal expansion of liquid, heated by sun, as driving force. Unlike most thermally powered systems, it does not require that liquid be converted into vapor.
Garvin-Doxas, Kathy; Klymkowsky, Michael; Elrod, Susan
2007-01-01
The meeting "Conceptual Assessment in the Biological Sciences" was held March 3-4, 2007, in Boulder, Colorado. Sponsored by the National Science Foundation and hosted by University of Colorado, Boulder's Biology Concept Inventory Team, the meeting drew together 21 participants from 13 institutions, all of whom had received National Science Foundation funding for biology education. Topics of interest included Introductory Biology, Genetics, Evolution, Ecology, and the Nature of Science. The goal of the meeting was to organize and leverage current efforts to develop concept inventories for each of these topics. These diagnostic tools are inspired by the success of the Force Concept Inventory, developed by the community of physics educators to identify student misconceptions about Newtonian mechanics. By working together, participants hope to lessen the risk that groups might develop competing rather than complementary inventories.
Innate intelligence: its origins and problems
Morgan, Lon
1998-01-01
Animal Magnetism and Radionics were among several occult practices used during the 19th century for the treatment of disease. D.D. Palmer was exposed to these teachings and derived many of his ideas about health from the folk medicine practices of his time. As a ‘magnetic healer’ Palmer believed he was correcting an undefined fifth force in the body that is otherwise unknown to science. Palmer believed he could influence this fifth force, termed Innate Intelligence, and that it was the explanation for the presence or absence of health. Today, Innate Intelligence remains an untestable enigma that isolates chiropractic and impedes its acceptance as a legitimate health science. The concept of Innate is derived directly from the occult practices of another era. It carries a high penalty in divisiveness and lack of logical coherence. The chiropractic profession must decide whether the concept of Innate should be retained.
Gender Differences in Both Force Concept Inventory and Introductory Physics Performance
NASA Astrophysics Data System (ADS)
Docktor, Jennifer; Heller, Kenneth
2008-10-01
We present data from a decade of introductory calculus-based physics courses for science and engineering students at the University of Minnesota taught using cooperative group problem solving. The data include 40 classes with more than 5500 students taught by 22 different professors. The average normalized gain for males is 0.4 for these large classes that emphasized problem solving. Female students made up approximately 20% of these classes. We present relationships between pre and post Force Concept Inventory (FCI) scores, course grades, and final exam scores for females and males. We compare our results with previous studies from Harvard [2] and the University of Colorado [3,4]. Our data show there is a significant gender gap in pre-test FCI scores that persists post-instruction although there is essentially no gender difference in course performance as determined by course grade.
Free-Flight Evaluation of Forebody Blowing for Yaw Control at High Angels of Attack
NASA Technical Reports Server (NTRS)
Kiddy, Jason
1995-01-01
Forebody blowing is a concept developed to provide yaw control for aircraft flying at high angles of attack where a conventional rudder becomes ineffective. The basic concept is fairly simple. A small jet of air is forced out of the nose of the aircraft. This jet causes a repositioning of the forebody vortices in an asymmetrical fashion. The asymmetric forebody vortex flows develop a side force on the forebody which results in substantial yawing moments at high angles of attack. The purpose of this project was to demonstrate the use of forebody blowing as a control device through free-flight evaluation. This unique type of testing was performed at the NASA-Langley 30- by 60-foot tunnel. From these tests, it could then be shown that forebody blowing is an effective method of maintaining yaw control at high angles of attack.
Motivating forces of human actions. Neuroimaging reward and social interaction.
Walter, Henrik; Abler, Birgit; Ciaramidaro, Angela; Erk, Susanne
2005-11-15
In neuroeconomics, reward and social interaction are central concepts to understand what motivates human behaviour. Both concepts are investigated in humans using neuroimaging methods. In this paper, we provide an overview about these results and discuss their relevance for economic behaviour. For reward it has been shown that a system exists in humans that is involved in predicting rewards and thus guides behaviour, involving a circuit including the striatum, the orbitofrontal cortex and the amygdala. Recent studies on social interaction revealed a mentalizing system representing the mental states of others. A central part of this system is the medial prefrontal cortex, in particular the anterior paracingulate cortex. The reward as well as the mentalizing system is engaged in economic decision-making. We will discuss implications of this study for neuromarketing as well as general implications of these results that may help to provide deeper insights into the motivating forces of human behaviour.
Adaptive enhanced sampling by force-biasing using neural networks
NASA Astrophysics Data System (ADS)
Guo, Ashley Z.; Sevgen, Emre; Sidky, Hythem; Whitmer, Jonathan K.; Hubbell, Jeffrey A.; de Pablo, Juan J.
2018-04-01
A machine learning assisted method is presented for molecular simulation of systems with rugged free energy landscapes. The method is general and can be combined with other advanced sampling techniques. In the particular implementation proposed here, it is illustrated in the context of an adaptive biasing force approach where, rather than relying on discrete force estimates, one can resort to a self-regularizing artificial neural network to generate continuous, estimated generalized forces. By doing so, the proposed approach addresses several shortcomings common to adaptive biasing force and other algorithms. Specifically, the neural network enables (1) smooth estimates of generalized forces in sparsely sampled regions, (2) force estimates in previously unexplored regions, and (3) continuous force estimates with which to bias the simulation, as opposed to biases generated at specific points of a discrete grid. The usefulness of the method is illustrated with three different examples, chosen to highlight the wide range of applicability of the underlying concepts. In all three cases, the new method is found to enhance considerably the underlying traditional adaptive biasing force approach. The method is also found to provide improvements over previous implementations of neural network assisted algorithms.
Evaluation of instability forces of labyrinth seals in turbines or compressors
NASA Technical Reports Server (NTRS)
Iwatsubo, T.
1980-01-01
The effects of a force induced by the labyrinth seal on the stability of rotor systems and the factors of the seal which affect the stability are investigated. In the analysis, it is assumed that the fluid in the seal is steady and that the rotor is set vertically in order to avoid the effects of gravity force. The force induced by the seal is expressed in terms proportional to the velocity and displacement of the rotor and is deduced to that expression for the oil film force in journal bearings. That force is taken into account in the equations of motion; then the stability of the system is discussed by energy concept. The force induced by the labyrinth seal always makes the rotor system unstable, and the tendency is marked when seal leakages are small. The resonance point of the rotor system is also affected by the labyrinth seal (the resonance point of the rotor system is removed by the seal leakages). The force induced by the labyrinth seal was measured by using a water-tunnel experimental system which was designed to measure the labyrinth seal force by using the similarity between gas and liquid flow theory.
Pre-service Elementary Teachers Understanding on Force and Motion
NASA Astrophysics Data System (ADS)
Anggoro, S.; Widodo, A.; Suhandi, A.
2017-09-01
The research is done to investigate the understanding on the subtopic of Force and Motion that exists among the pre-services elementary teachers. The participants were 71 Elementary Teachers Study Program students in 6th and 77 one in 2nd semester at private university. Research instrument consisted of background information of respondents, belief of preconception and 8 questions that relates to Force and Motion with four alternative answers and their explained. Descriptive statistics such as percentage and bar chart were used for analyzing the data collected. Research findings have shown many participants have some misunderstand or misconception conception especially in free fall object, rest object, buoyant force and gravitation. This research recommends learning progression pre-services teachers to be exposed with conflict cognitive strategy for science conceptual change.
Force-controlled manipulation of single cells: from AFM to FluidFM.
Guillaume-Gentil, Orane; Potthoff, Eva; Ossola, Dario; Franz, Clemens M; Zambelli, Tomaso; Vorholt, Julia A
2014-07-01
The ability to perturb individual cells and to obtain information at the single-cell level is of central importance for addressing numerous biological questions. Atomic force microscopy (AFM) offers great potential for this prospering field. Traditionally used as an imaging tool, more recent developments have extended the variety of cell-manipulation protocols. Fluidic force microscopy (FluidFM) combines AFM with microfluidics via microchanneled cantilevers with nano-sized apertures. The crucial element of the technology is the connection of the hollow cantilevers to a pressure controller, allowing their operation in liquid as force-controlled nanopipettes under optical control. Proof-of-concept studies demonstrated a broad spectrum of single-cell applications including isolation, deposition, adhesion and injection in a range of biological systems. Copyright © 2014 Elsevier Ltd. All rights reserved.
Validation of engineering methods for predicting hypersonic vehicle controls forces and moments
NASA Technical Reports Server (NTRS)
Maughmer, M.; Straussfogel, D.; Long, L.; Ozoroski, L.
1991-01-01
This work examines the ability of the aerodynamic analysis methods contained in an industry standard conceptual design code, the Aerodynamic Preliminary Analysis System (APAS II), to estimate the forces and moments generated through control surface deflections from low subsonic to high hypersonic speeds. Predicted control forces and moments generated by various control effectors are compared with previously published wind-tunnel and flight-test data for three vehicles: the North American X-15, a hypersonic research airplane concept, and the Space Shuttle Orbiter. Qualitative summaries of the results are given for each force and moment coefficient and each control derivative in the various speed ranges. Results show that all predictions of longitudinal stability and control derivatives are acceptable for use at the conceptual design stage.
NASA Technical Reports Server (NTRS)
Capone, F. J.
1975-01-01
An investigation was conducted in the Langley 16-foot transonic tunnel to determine the induced lift characteristics of a vectored thrust concept in which a rectangular jet exhaust nozzle was located in the fuselage at the wing trailing edge. The effects of nozzle deflection angles of 0 deg to 45 deg were studied at Mach numbers from 0.4 to 1.2, at angles of attack up to 14 deg, and with thrust coefficients up to 0.35. Separate force balances were used to determine total aerodynamic and thrust forces as well as thrust forces which allowed a direct measurement of jet turning angle at forward speeds. Wing pressure loading and flow characteristics using oil flow techniques were also studied.
Desselle, Shane P; Peirce, Gretchen L; Crabtree, Brian L; Acosta, Daniel; Early, Johnnie L; Kishi, Donald T; Nobles-Knight, Dolores; Webster, Andrew A
2011-05-10
Many factors contribute to the vitality of an individual faculty member, a department, and an entire academic organization. Some of the relationships among these factors are well understood, but many questions remain unanswered. The Joint Task Force on Faculty Workforce examined the literature on faculty workforce issues, including the work of previous task forces charged by the American Association of Colleges of Pharmacy (AACP). We identified and focused on 4 unique but interrelated concepts: organizational culture/climate, role of the department chair, faculty recruitment and retention, and mentoring. Among all 4 resides the need to consider issues of intergenerational, intercultural, and gender dynamics. This paper reports the findings of the task force and proffers specific recommendations to AACP and to colleges and schools of pharmacy.
Dramatic (and Simple!) Demonstration of Newton's Third Law
NASA Astrophysics Data System (ADS)
Feldman, Gerald
2011-02-01
An operational understanding of Newton's third law is often elusive for students. Typical examples of this concept are given for contact forces that are closer to the students' everyday experience. While this is a good thing in general, the reaction force can sometimes be taken for granted, and the students can miss the opportunity to really think about what is going on. In the case of magnetic forces, however, the notion of action at a distance actually requires a careful inspection of the forces involved and thereby promotes a more detailed analysis of the situation. In this paper, a simple demonstration of Newton's third law is presented in the context of a magnet falling through a hollow conducting tube. The results are unambiguous and lead the students to an irrefutable verification of Newton's third law.
NASA Lewis Research Center Workshop on Forced Response in Turbomachinery
NASA Technical Reports Server (NTRS)
Stefko, George L. (Compiler); Murthy, Durbha V. (Compiler); Morel, Michael (Compiler); Hoyniak, Dan (Compiler); Gauntner, Jim W. (Compiler)
1994-01-01
A summary of the NASA Lewis Research Center (LeRC) Workshop on Forced Response in Turbomachinery in August, 1993 is presented. It was sponsored by the following NASA organizations: Structures, Space Propulsion Technology, and Propulsion Systems Divisions of NASA LeRC and the Aeronautics and Advanced Concepts & Technology Offices of NASA Headquarters. In addition, the workshop was held in conjunction with the GUIde (Government/Industry/Universities) Consortium on Forced Response. The workshop was specifically designed to receive suggestions and comments from industry on current research at NASA LeRC in the area of forced vibratory response of turbomachinery blades which includes both computational and experimental approaches. There were eight presentations and a code demonstration. Major areas of research included aeroelastic response, steady and unsteady fluid dynamics, mistuning, and corresponding experimental work.
NASA Astrophysics Data System (ADS)
Liu, Mingyue; Xiao, Longfei; Yang, Lijun
2015-09-01
The Deep Draft Semi-Submersible (DDS) concepts are known for their favourable vertical motion performance. However, the DDS may experience critical Vortex-Induced Motion (VIM) stemming from the fluctuating forces on the columns. In order to investigate the current-induced excitation forces of VIM, an experimental study of flow characteristics around four square-section cylinders in a square configuration is presented. A number of column spacing ratios and array attack angles were considered to investigate the parametric influences. The results comprise flow patterns, drag and lift forces, as well as Strouhal numbers. It is shown that both the drag and lift forces acting on the cylinders are slightly different between the various L/D values, and the fluctuating forces peak at L/D = 4.14. The lift force of downstream cylinders reaches its maximum at around α = 15°. Furthermore, the flow around circular-section-cylinder arrays is also discussed in comparison with that of square cylinders.
Experiments evaluating compliance and force feedback effect on manipulator performance
NASA Technical Reports Server (NTRS)
Kugath, D. A.
1972-01-01
The performance capability was assessed of operators performing simulated space tasks using manipulator systems which had compliance and force feedback varied. Two manipulators were used, the E-2 electromechanical man-equivalent (force, reach, etc.) master-slave system and a modified CAM 1400 hydraulic master-slave with 100 lbs force capability at reaches of 24 ft. The CAM 1400 was further modified to operate without its normal force feedback. Several experiments and simulations were performed. The first two involved the E-2 absorbing the energy of a moving mass and secondly, guiding a mass thru a maze. Thus, both work and self paced tasks were studied as servo compliance was varied. Three simulations were run with the E-2 mounted on the CAM 1400 to evaluate the concept of a dexterous manipulator as an end effector of a boom-manipulator. Finally, the CAM 1400 performed a maze test and also simulated the capture of a large mass as the servo compliance was varied and with force feedback included and removed.
PDC bits break ground with advanced vibration mitigation
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1995-10-01
Advancements in PDC bit technology have resulted in the identification and characterization of different types of vibrational modes that historically have limited PDC bit performance. As a result, concepts have been developed that prevent the initiation of vibration and also mitigate its damaging effects once it occurs. This vibration-reducing concept ensures more efficient use of the energy available to a PDC bit performance. As a result, concepts have been developed that prevent the imitation of vibration and also mitigate its damaging effects once it occurs. This vibration-reducing concept ensures more efficient use of the energy available to a PDC bit,more » thereby improving its performance. This improved understanding of the complex forces affecting bit performance is driving bit customization for specific drilling programs.« less
Environmental sentinel biomonitors: integrated response systems for monitoring toxic chemicals
NASA Astrophysics Data System (ADS)
van der Schalie, William H.; Reuter, Roy; Shedd, Tommy R.; Knechtges, Paul L.
2002-02-01
Operational environments for military forces are becoming potentially more dangerous due to the increased number, use, and misuse of toxic chemicals across the entire range of military missions. Defense personnel may be exposed to harmful chemicals as a result of industrial accidents or intentional or unintentional action of enemy, friendly forces, or indigenous populations. While there has been a significant military effort to enable forces to operate safely and survive and sustain operations in nuclear, biological, chemical warfare agent environments, until recently there has not been a concomitant effort associated with potential adverse health effects from exposures of deployed personnel to toxic industrial chemicals. To provide continuous real-time toxicity assessments across a broad spectrum of individual chemicals or chemical mixtures, an Environmental Sentinel Biomonitor (ESB) system concept is proposed. An ESB system will integrate data from one or more platforms of biologically-based systems and chemical detectors placed in the environment to sense developing toxic conditions and transmit time-relevant data for use in risk assessment, mitigation, and/or management. Issues, challenges, and next steps for the ESB system concept are described, based in part on discussions at a September 2001 workshop sponsored by the U.S. Army Center for Environmental Health Research.
Bio-inspired device: a novel smart MR spring featuring tendril structure
NASA Astrophysics Data System (ADS)
Kaluvan, Suresh; Park, Chun-Yong; Choi, Seung-Bok
2016-01-01
Smart materials such as piezoelectric patches, shape memory alloy, electro and magneto rheological fluid, magnetostrictive materials, etc are involved by far to design intelligent and high performance smart devices like injectors, dental braces, dampers, actuators and sensors. In this paper, an interesting smart device is proposed by inspiring on the structure of the bio climber plant. The key enabling concept of this proposed work is to design the smart spring damper as a helical shaped tendril structure using magneto-rheological (MR) fluid. The proposed smart spring consists of a hollow helical structure filled with MR fluid. The viscosity of the MR fluid decides the damping force of helical shaped smart spring, while the fluid intensity in the vine decides the strength of the tendril in the climber plant. Thus, the proposed smart spring can provide a new concept design of the damper which can be applicable to various damping system industries with tuneable damping force. The proposed smart spring damper has several advantageous such as cost effective, easy implementation compared with the conventional damper. In addition, the proposed spring damper can be easily designed to adapt different damping force levels without any alteration.