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Linearity assessment between lower limb joint angles and angular accelerations at standard maximum vertical jumps with long-short and no countermovement

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Gait & Posture 2023年 106卷 S174-S175页

作者： Rodrigues, Carlos Correia, Miguel Abrantes, João Benedetti, Marco Nadal, Jurandir Faculty of Engineering- University of Porto Biomedical Engineering Program Porto Portugal INESC TEC - Institute for Systems and Computer Engineering- Technology and Science C-BER - Centre for Biomedical Engineering Research Porto Portugal Faculty of Engineering- University of Porto Department of Electrical and Computer Engineering Porto Portugal CICANT - Centre for Research in Applied Communication- Culture and New Technologies MovLab - Laboratory of Technologies for Interactions and Interfaces Lisbon Portugal Federal University of Pernambuco Department of Electronic and Systems Recife Brazil Federal University of Rio de Janeiro Biomedical Engineering Program Rio de Janeiro Brazil

IntroductionStandard maximum vertical jump (MVJ) has been applied to assess lower limb long countermovement (CM) on countermovement jump (CMJ) and short CM on drop jump (DJ) for comparison to squat jump (SJ) without CM [1,2]. Research questionNevertheless, the ability for lower limb joint accelerations depending on lower limb joint angles at long, short and no CM remains an open issue [3,4], in particular linearity assessment of these relations at long, short and no CM in association with MVJ whole-body impulsion. MethodsFor this reason, we applied piecewise linear detection of segmented subphases on lower limb joint angles ( θ)-angular acceleration ( α) diagrams for the hip (H), knee (K) and ankle (A) during impulse phases on CMJ, DJ and SJ. Selected sample corresponds to best MVJ trials based on higher flight-time of 3 CMJ, DJ and SJ repetitions for six healthy untrained subjects with ages (21.5±1.4) years, (76.7±9.3)kg mass and (1.79±0.06)m height. Adhesive reflective markers were applied at lower limb and torso, with sagittal hip, knee, and ankle θ, α obtained by inverse kinematics. H,K,A ( θ, α) diagrams were plotted and impulsion subphases segmented at selected instants of ∂ a/∂ q phase reversal with linear fit by the least-squares method, Fig. 1. Fig. 1. Hip, knee, ankle joint ( θ, α) diagrams at CMJ, DJ, SJ with segmented subphases time span(Δt), |∂α/∂θ| slope magnitudes and R² linear fit regression. ResultsSJ presented larger number of ( θ, α) subphases than DJ, both larger than CMJ with higher |∂ α/∂ θ| variation at DJ and SJ than CMJ, pointing to higher complexity of neuromuscular control and contributing to explain reduced SJ, DJ performance without CM (0.33±0.05)m and with short CM (0.27±0.03)m in relation to CMJ with long CM (0.36±0.04)m for untrained selected subjects, Fig. 1. Thus, despite the larger total time span Δt at CMJ (0.76±0.10)s in relation to SJ (0.36±0.08)s and DJ (0.23±0.05)s, CMJ presented lower number of subphases with longer time span

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Muscle coactivation analysis for neuromuscular control assessment of lower limb stretch-shortening cycle

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Gait & Posture 2023年 106卷 S175-S176页

IntroductionMuscle stretch-shortening cycle (SSC) is a central mechanism with lower limb muscle contraction immediately preceded by muscle stretch for efficient submaximal activities such as gait and powerful maximal activities such as running and jumping [1,2]. Research questionAlthough muscle SSC can be observed at gait and running its higher expression and accessibility is performed on standard maximum vertical jump (MVJ) with an open issue on neuromuscular control assessment of lower limb muscle SSC [3]. MethodsFor this purpose, we present and applied noninvasive subject specific analysis of lower limb muscle coactivation for selected muscles with higher contribution during MVJ impulse based on corresponding conditioned surface electromyographic signals (sEMG). Selected muscles correspond to lower limb muscles vastus medialis (VM), rectus femoris (RF), vastus lateralis (VL), lateral gastrocnemius (LG) and medial gastrocnemius (MG). Twenty-seven trials were assessed corresponding for each subject to the highest MVJ based on larger flight time with long SSC at countermovement jump (CMJ), short SSC at drop jump (DJ) and squat jump (SJ) with no SSC. Trial sample is composed by a group of six young adult volunteers’ students on sports and physical education degree with the ages (21.5 ± 1.4) years, (76.7 ± 9.3) kg mass and (1.79 ± 0.06) m height. Surface skin was prepared and Aqua-Wet gel Skintact F55 electrodes were applied at bipolar configuration as indicated by SENIAN. VM, RF, VL, LG and MG sEMG linear envelopes were paired plotted with the area under the curves computed as well as the coactivation pairs defined as the common area under the curves normalized to the sum of the corresponding pair individual areas under the curves. Coactivations were compared at CMJ, DJ and SJ as well as among CMJ, DJ and SJ, Fig. 1. ResultsStrongest coactivations with decreasing intensity were detected between VM-RF and LG-MG muscles at CMJ and SJ, whereas at DJ the strongest coacti

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Waters network's potential to transform environmental engineering education

Waters network's potential to transform environmental engine...

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114th Annual ASEE Conference and Exposition, 2007

作者： Eschenbach, Elizabeth Montgomery, Jami Johnson, James Brus, Chris Carlson, Patricia Giammar, Dan Grauer, Bette Hotaling, Liesl Oguntimein, Gbekeloluwa Safferman, Steven Wentling, Tim Humboldt State University United States Department of Environmental Resources Engineering Humboldt State University United States WATERS Network - CLEANER Project Office Network Howard University United States Department of Environmental Engineering College of Engineering Architecture and Computer Sciences Howard University United States American Academy of Environmental Engineers United States University of Iowa United States Program University of Iowa United States Rose-Hulman Institute of Technology United States Department of Rhetoric Rose-Hulman Institute of Technology United States National Research Council U. S. Air Force United States NASA's Classroom of the Future Wheeling WV United States Washington University United States Department of Energy Environmental and Chemical Engineering Washington University St. Louis United States Environmental Studies Program Center for Materials Innovation United States McPherson High School United States McPherson High School McPherson KS United States Stevens Institute of Technology United States Stevens Institute of Technology United States Morgan State University United States Michigan State University United States Biosystems and Agricultural Engineering Department Michigan State University United States University of Dayton United States Education Planning Committee National Center for Supercomputing Applications United States Department of Information Science Graduate School of Library and Information Science National Center for Supercomputing Applications University or Illinois United States Knowledge and Learning Systems Group NCSA United States

The WATERS Network (WATer and Environmental Research systems Network) will be an integrated real-time distributed observing system which will enable academic and government scientists, engineers, educators, and practitioners to advance effective management of our nation's water resources by understanding human interactions with water and the natural and built environment. WATERS will provide easily accessible real time environmental data as well as analysis tools to engineers, scientists, educators, K- graduate students and policymakers so they can better understand how water quantity, quality and related components of the hydrologic cycle are impacted by natural and human influences. The WATERS strategic plan will be completed by July 2007 and requires constituent input. This paper describes the draft Conceptual Design and the Education Plan of WATERS Network. This paper will highlight the potential impact of WATERS on undergraduate and graduate environmental engineering education in order to elicit input from the environmental engineering education community on how WATERS Network could better meet the future needs of undergraduate and graduate students and educators. More information can be found at ***. © American Society for engineering Education, 2007.

关键词： Water resources

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Improvement of convergence speed for subband adaptive digital filter using the multirate repeating method

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ELECTRONICS AND COMMUNICATIONS IN JAPAN PART III-FUNDAMENTAL ELECTRONIC SCIENCE 1995年第10期78卷 37-45页

作者： Kiya, H Nishikawa, K Ashihara, K Faculty of Technology Tokyo Metropolitan University Hachioji Japan 192-03 Members Kiyoshi Nshikawa graduated in 1990 from the Department of Electrical Engineering Tokyo Metropolitan University where he completed the Master's Program in 1992 and affiliated with Nippon Steel Co. Computer Systems Laboratory. He was a Research Associate in 1993 in the Department of Elect. Inf. Eng. Tokyo Metropolitan University engaged in research onadaptive signal processing and information source coding. He is a member of the IEEE. Associate Member

The subband adaptive system, where the idea of the filter bank is applied to the adaptive filter, has a feature that a higher-order adaptation can be reduced to lower-order adaptations. The reduction of the order of the adaptive filter is related closely to the number of channels and the decimation ratio. The order of adaptive digital filter (ADF) is decreased greatly when the number of subbands is increased, and the decimation ratio is increased up to the maximum value. Then, however, the number of coefficient-updates per unit time is decreased, which results in the deterioration of the convergence Speed. From such a viewpoint, this paper discusses a method to improve the convergence speed, which is deteriorated in the subband adaptive system, due to the decimation. The idea of the proposed method is to utilize effectively the data which have been discarded in the decimation process and to improve the convergence speed. It is called the multirate repeating method. As the first step, the multirate repeating method is applied to the conventional subband adaptive system and the convergence speed is improved. Then a subband adaptive system is introduced in which the multirate repeating method can be utilized more effectively. As a result, a faster convergence is realized while retaining the ADF order-reduction effect, which is an advantage of the subband adaptive system.

关键词： adaptive signal processing subband adaptive system multirate repeating method rational decimation

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Numerical analysis of general-vibration-based method for structural health monitoring

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AIP Conference Proceedings 2020年第1期2227卷

作者： Fergyanto E. Gunawan Benfano Soewito Nico Surantha Tuga Mauritsius Nobumasa Sekishita 1Industrial Engineering Department BINUS Graduate Program - Master of Industrial Engineering Bina Nusantara University Jakarta Indonesia 11480 2Computer Science Department BINUS Graduate Program - Master of Computer Science Bina Nusantara University Jakarta Indonesia 11480 3Information Systems Management Department BINUS Graduate Program - Master of Information Systems Management Bina Nusantara University Jakarta Indonesia 11480 4Department of Mechanical Engineering Toyohashi University of Technology Toyohashi Aichi 441-8580 Japan

For damage detection, this research article discusses an easy-to-compute damage index derived from the governing dynamic of the structure that has potential practical application in Structural Health Monitoring (SHM). The research uses simplified structural models to explore the sensitivity of the index to damages, to compare the index performance with a traditional but popular damage detection method, and to understand the local/global predictive capability of the index. The research uses two simple models, namely, single- and two-degree-of-freedom systems. The results suggest that the damage index is local, that can only monitor damages occurring near the points of measurements, but it is sensitive to damages, unlike the natural frequency, which is global but less sensitive.

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The accuracy of the F statistic for structural health monitoring

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AIP Conference Proceedings 2020年第1期2227卷

作者： Fergyanto E. Gunawan Benfano Soewito Nico Surantha Tuga Mauritsius Nobumasa Sekishita 1Industrial Engineering Department BINUS Graduate Program – Master of Industrial Engineering Bina Nusantara University Jakarta Indonesia 11480 2Computer Science Department BINUS Graduate Program – Master of Computer Science Bina Nusantara University Jakarta Indonesia 11480 3Information Systems Management Department BINUS Graduate Program – Master of Information Systems Management Bina Nusantara University Jakarta Indonesia 11480 4Department of Mechanical Engineering Toyohashi University of Technology Toyohashi Aichi 441-8580 Japan

Understanding the reliability of engineering methods is crucial for its adoption and deployment. This research focuses on the reliability of the Power Spectral Density (PSD) method via the use of the F statistic for damage detection. To the author best knowledge, the method is rather classic but its realibility has not been discussed in the context of a large data size. Priory, the research anticipates that the accuracy is a function of the damage level. In this study, we evaluate 3500 cases with five levels of structural integrity, namely, healthy condition and damaged conditions with 1%, 5%, 10%, and 20% damage levels. The dataset is established via a numerical analysis of a seven degree-of-freedom system loaded with a concentrated dynamic force with random magnitude. A spring on the system is reduced in its stiffness to simulate damages. Our significant findings are the following: it is challenging for the PSD-based method to differentiate the healthy condition from the damaged conditions when the damage level is small. However, the reliability is high at 95% probability when the structural integrity has dropped by five percent.

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DESIGN, CONSTRUCTION, AND MODERNIZATION OF SHIPS WITH THE SHIPBOARD DATA MULTIPLEX SYSTEM (SDMS)

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NAVAL ENGINEERS JOURNAL 1979年第5期91卷 65-73页

作者： BOLD, NT BOURETTE, AP Dr. Norbert T. Bold graduated from Marquette University and later received his M.S. and Ph.D. degrees in Electrical Engineering from Northwestern University. He served three years as a Naval Engineering Officer aboard an Aircraft Carrier and a Minesweeper and has nineteen years technical experience in shipboard navigation underwater target and SDMS projects for the Navy. He is currently a Program Manager in the Autonetics Marine Systems Division Rockwell International where his primary assignment is the development of advanced concepts and applications of SDMS to Navy programs. He has published several technical papers. was elected to four Scholastic Honorary Societies and was the recipient of a NROTC Scholarship. Mr. A.P. Bourette Manager Systems Applications Autonetics Marine Systems Division. received his B.S. degree in Mathematical Physics from Long Beach State University. He began his career with a Computer Analysis Unit. performing tasks related to computer application. programming and interfacing. He has made significant contributions to the Central Computer Complex approach adopted for the SSN-688 Combat System and has performed inertial systems engineering efforts on the MK2 SINS for the POSEIDON Program. He spent some time in the Washington D.C. area providing technical expertise to various Navy organizations. Upon his return he soon was selected to manage the Systems Applications organization at Rockwell International. This organization is primarily responsible for the Shipboard Application of SDMS. He has directed several application studies showing the significant advantages associated with multiplexing. Recently. he provided the technical direction for the FY80 SSN SDMS Preliminary Design Phase.

Rockwell International is currently under Navy contract to fabricate the engineering Development Model (EDM) of the Shipboard Data Multiplex System (SDMS) for general data transfer aboard surface ships and submarines. The application of SDMS significantly reduces hardware such as cables, switchboards, and Signal Data Converters (SDC), and it provides the capability to add many desired features which are currently not practicable. In applying SDMS to a specific ship, a massive amount of signal data must be considered. The Application Design Automation program (ADAP) is a set of computer programs that have been developed to accomplish this task. ADAP com bines signal population data, ships configuration data, and SDMS hardware characteristics to produce an SDMS configuration layout together with documentation necessary to analyze, evaluate, and implement the system. Specific outputs include hardware requirements, system layout, and interface requirements including wire list information. The Timing, Event and Load Simulation (TELS) program simulates SDMS and provides performance data (system capacity, throughput rate, transport delays) for any system configuration. Conventional SDCs can be elimianted from Navy shipboard systems when SDMS is used. SDMS provides the necessary data distribution, signal conversion, and computer interface. In addition, many functions of the conventional switchboards can be performed within SDMS, thus reducing the size or eliminating conventional switchboards. Very small switch-bomb will provide the necessary control of data distribution. With SDMS, an automatic and continuous Noise and Vibration Monitoring (NVM) capability is readily available. The automated NVM function will enhance the safety, operation, and maintenance of the ship. Problems with machinery or excessive self-noise generation will be detected much sooner, and corrective action implemented on a timely basis.

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SHIP SERVICE ELECTRICAL systems - DESIGNING FOR SURVIVABILITY

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NAVAL ENGINEERS JOURNAL 1990年第5期102卷 32-36页

作者： CERMINARA, J KOTACKA, RO John Cerminara:is a principal engineer with Westinghouse Machinery Technology Division Electrical Systems Department. He holds a B.S. degree in electrical engineering from the University of Pittsburgh. He is a registered professional engineer and a member of IEEE ASNE and the Ship Steering Group of the Combat Survivability Division of ADPA. Mr. Cerminara has had over 30 years of multidiscipline experience ranging from engineering and construction in heavy industry to standards and publications. Past assignments include DOE/ NASA wind turbine project manager for Westinghouse and task leader of MTD electrical systems. Most recent assignments have included hull mechanical and electrical (HM&E) distributive system survivability analyses of the LSD-41 mobility mission area and application and validation of NavSea computer-aided design of Survivable Distributive System (CADSDiS) Program. Rolf O. Kotacka:is presently a ship systems engineer in the Ship Systems Engineering Branch of the Naval Sea Systems Command Engineering Directorate where his primary responsibility is ship system survivability. He is a 1977 graduate of SUNY Maritime College where he received his bachelor of engineering degree in marine electrical engineering as well as a U.S. Coast Guard Third Assistant Engineer License and a commission in the U. S. Naval Reserve. Upon graduation Mr. Kotacka was employed by Charleston Naval Shipyard as a field engineer until 1981 where he gained his background in surface ship HM&E systems and equipment. He then transferred to the Supervisor of Shipbuilding Conversion and Repair Groton where he served as a senior electrical engineer monitoring the design and construction of Trident and 688 class submarines and received the Meritorious Unit Citation. Prior to his present position Mr. Kotacka was the life cycle manager for diesel generator sets in the Naval Sea Systems Command's Generators Branch. He has coauthored several papers dealing with power generation for ASE and SNAME. Mr. Kotacka is also a lieutena

This paper highlights the survivability concerns in the design of ship service power systems. The paper gives a brief description of what constitutes a typical ship service electric power system and concentrates on electric power generation and associated controls. Established survivability design principles and guidelines are highlighted and the application of those guidelines are discussed. General Specifications (Gen Specs) for Ships of the U.S. Navy are cited as the cornerstone for design. Specific design criteria are cited as well as the rationale associated with the survivability design guidelines pertaining to power generation and distribution. The application of these survivability design guidelines plus the use of the deactivation diagram/damage tolerance analysis cited in the Gen Spec section 072e will enhance overall design and help ensure survivable electric power systems for surface combatants.

关键词： Warships

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THE ROLE OF PERFORMANCE ANALYSIS IN THE LIFE-CYCLE OF A WEAPONS SYSTEM

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NAVAL ENGINEERS JOURNAL 1987年第3期99卷 239-248页

作者： BAILEY, JL The authoris an operations research analyst in the Systems Engineering Branch Aegis Ship Combat Systems Division at the Naval Surface Weapons Center (NSWC). Dr. Bailey received a B. S. degree in mathematics from the Massachusetts Institute of Technology in 1964 a Ph.D. in mathematics from the University of Tennessee in 1968 and an M. S. in computer science from the Virginia Polytechnic Institute and State University in 1975. He was an assistant professor of mathematics at the University of Tennessee during the 1968-69 academic year then came to NSWC/Dahlgren in September 1969. He worked as an operations research analyst in mine warfare from 1969 to 1978 specializing in minefield planning. He headed the group which developed the minefield planning module of the Mine Warfare Trainer which was delivered to the Fleet and Mine Warfare Training Center in 1978-79. Dr. Bailey served as science advisor to the commander Mine Warfare Command in 1978-79 under the sponsorship of the Navy Science Assistance Program. In 1979-80 he led the development of military value assessment methodology for a ship survivability improvement program. In 1980 he moved to the Aegis Ship Combat Systems Division becoming leader of the Systems Performance Assessment Group in 1981. Dr. Bailey leads a group of analysts who do assessment of the predicted performance of the Aegis combat system and the effects of proposed changes to the system. Dr. Bailey has also served collateral duty as systems analysis manager for the Technical Division of the Aegis Project Office (PMS-400) in the Naval Sea Systems Command since 1981.

Performance analysis is the process of determining the predicted performance of a weapons system. It is generally used to examine predicted performance of systems in a variety of configurations and operational situations; it is accomplished through a variety of techniques, from the computation of straightforward algebraic functions to complex computer simulations. Performance analysis is necessary throughout the life-cycle of weapons systems. It is used to help determine original requirements, for conceptual and detailed design, and to support operational planning and determine upgrade requirements. The development, maintenance, and consistent application of a set of system specific performance analysis methods have enhanced the development of many weapons systems. This paper is in the form of a tutorial on the application of performance analysis techniques, using the development of the Aegis weapons system as a source of examples, and stressing the value of performance analysis methods which have been designed specifically for the Aegis system.

关键词： MILITARY EQUIPMENT

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USING VIRTUAL ENVIRONMENTS IN THE DESIGN OF SHIPS

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NAVAL ENGINEERS JOURNAL 1994年第3期106卷 91-106页

作者： JONS, OP RYAN, JC JONES, GW Otto P. Jons:received a Diplom Ing. in shipbuilding from the Technical University of Hanover W. Germany and an MS in naval architecture and marine engineering from MIT. He then joined Litton Ship Systems where he was responsible for the preliminary design of the DD-963 hull structure and then for ship system integration as manager LHA ship systems engineering department. From 1972 to 1974 he was the principal research scientist at Hydronautics. In 1974 as technical director he helped establish the Crystal City office of Designers and Planners. Mr. Jons was one of the co-founders of Advanced Marine Enterprises Inc. in 1976 where he serves as corporate vice president engineering. J. Christopher Ryan:earned his bachelors and masters degrees in naval architecture from Webb Institute and MIT respectively. He spent three years at the advanced marine technology division of Litton Industries working on the DD-963 class ship design and related computer aided design projects. He subsequently went to the Navy Department concentrating on early stage design of surface combatants for twelve years including work on the FFG-7 Sea Control Ship CSGN and CVV aircraft carrier projects. He then shifted focus and became the Technical Director for the Computer Supported Design Program in NavSea for five years. Mr. Ryan has served in several supervisory positions within the Ship Design Group in NavSea since that time. He is currently the director of the future ship concepts division. Gary W. Jones:graduated from the University of Tennessee in 1971 with a BS in mechanical engineering and followed up with graduate work at George Washington University and the University of Maryland. Mr. Jones was with the Naval Sea Systems Command from 1971 until 1988 where he was a naval architect in the submarine section of the hull form design division. In 1988 he was detailed to the Defense Advanced Research Projects Agency (DARPA) where he became the program manager for the advanced submarine technology program's hydrodynamic hydroac

A major contributor to the expense and length of time to design, build, and test new systems has been the need to build and test hardware prototypes to determine their effectiveness in meeting operational requirements. Recent and dramatic advances in computer simulation technologies hold forth the promise of revolutionizing design and acquisition strategies by providing the means to validate end users' requirements prior to hardware construction. By designing and operationally testing virtual prototypes in a virtual environment, these technologies will soon offer naval architects the ability to build and launch ships in computer-based cyberspace in lieu of the shipbuilder's ways. The authors of this paper provide the background for these developments, explore the significance and ramifications of these technologies to the current process of ship and system design, outline challenges lying ahead, and present their vision and recommendations for future development.

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