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1.
An examination into the effects of carried military equipment on the performance of two tactical combat movement simulations was conducted. Nineteen Airfield Defence Guards performed a break contact (five 30-m sprints) and a fire and movement simulation (16 6-m bounds) in five load conditions (10–30 kg). Heavier loads significantly increased movement duration on the break contact (0.8%/kg load) and fire and movement (1.1%/kg). Performance deterioration was observed from the beginning to the end of the series of movements (bounds or sprints) with deterioration becoming significantly greater in heavier load conditions. Inter-individual variation between slower and faster participants showed a range in load effects; 0.6, 0.8%/kg for fast and 1.0, 1.4%/kg for slow (break contact, fire and movement, respectively). Velocity profiles revealed that the initial acceleration and peak velocity were the primary determinants of performance. As the duration of these tactical combat movements reflects periods of heightened vulnerability, these findings highlight important implications for commanders.
Practitioner Summary: Increasing amounts of carried military equipment impairs the performance of tactical combat movements. Examination of inter-individual variation in velocity profiles identified that the initial acceleration and the peak velocity achieved during sprints and bounds are key determinants of overall performance. 相似文献
2.
In this investigation a new model was developed to calculate gas pressure at the melt/foam interface (Gap) resulting from foam degradation during mould filling in the lost foam casting (LFC) process. Different aspects of the process, such as foam degradation, gas elimination, transient mass, heat transfer, and permeability of the refractory coating were incorporated into this model. A computational fluid dynamic (CFD) code was developed based on the numerical technique of the SOLution Algorithm-Volume of Fluid (SOLA-VOF) utilizing model, for the simulation and prediction of the fluid flow in the LFC process. In order to verify the computational results of the simulation, a thin plate of grey iron was poured into a transparent foam mould. The mould filling process was recorded using a 16 mm high-speed camera. Images were analysed frame by frame, in order to measuring foam depolymerization rate and the gap volume during mould filling. Comparison between the experimental method and the simulation results, for the LFC filling sequence, has shown a good agreement. 相似文献
3.
P. T. Thompson R. Silk A. Herridge 《International Journal of Satellite Communications and Networking》1992,10(4):183-198
Developed primarily to provide continuation of services from the INTELSAT V satellites in the Pacific Ocean Region, this latest generation of satellites also has utility for operation in other roles. Several new technologies are combined to give cost-effective international satellite communications on a global, regional and domestic basis. This new higher power satellite will form a fundamental part of the INTELSAT global network, having been designed to match the projected traffic demands and future service requirements. 相似文献
4.
Tirthankar?GhoshEmail author Niki?Pissinou Kami?Sam?Makki 《Mobile Networks and Applications》2005,10(6):985-995
Designing a trusted and secure routing solution in an untrustworthy scenario is always a challenging problem. Lack of physical
security and low trust levels among nodes in an ad hoc network demands a secure end-to-end route free of any malicious entity.
This is particularly challenging when malicious nodes collude with one another to disrupt the network operation. In this paper
we have designed a secure routing solution to find an end-to-end route free of malicious nodes with collaborative effort from
the neighbors. We have also extended the solution to secure the network against colluding malicious nodes, which, to the best
of our knowledge, is the first such solution proposed. We have also proposed a framework for computing and distributing trusts
that can be used with out trusted routing protocol. Our proposed framework is unique and different from the other schemes
in that it tries to analyze the psychology of the attacker and quantifies the behavior in the computational model. Extensive
simulation has been carried out to evaluate the design of our protocol.
Partially funded by Department of Defense Award No. H98230-04-C-0460, Department of Transportation Project No. FL-26-7102-00
and National Science Foundation Grant Nos. ANI-0123950 and CCR-0196557.
Tirthankar Ghosh is a PhD candidate in the Telecommunications and Information Technology Institute at Florida International University. His
area of research is routing security and trust computation in wireless ad hoc and sensor networks. He received his Bachelor
of Electrical Engineering from Jadavpur University, India and Masters in Computer Engineering from Florida International University.
Dr. Niki Pissinou received her Ph.D. in Computer Science from the University of Southern California, her M.S. in Computer Science from the
University of California at Riverside, and her B.S.I.S.E. in Industrial and Systems Engineering from The Ohio State University.
She is currently a tenured professor and the director of the Telecommunication & Information Technology Institute at FIU.
Previously Dr. Pissinou was a tenured faculty at the Center for Advanced Computer Studies at the University of Louisiana at
Lafayette where she was also the director of the Telecommunication & Information & Technology Laboratory partially funded
by NASA, and the co-director of the NOMAD: A Wireless and Nomadic Laboratory partially funded by NSF, and the Advanced Network
Laboratory. Dr. Pissinou is active in the fields computer networks, information technology and distributed systems.
Dr. Kami (Sam) Makki has earned his Ph.D. in Computer Science from the University of Queensland in Brisbane Australia, his Masters degree in Computer
Science and Engineering from the University of New South Wales in Sydney Australia, and his Bachelor and Masters Degrees in
Civil Engineering from the University of Tehran Iran. Before joining the department of Electrical Engineering and Computer
Science at the University of Toledo he has held a number of academic positions and research appointments at the Queensland
University of Technology in Brisbane, Royal Melbourne Institution of Technology in Melbourne and at The University of Queensland
in Brisbane Australia. He is an active researcher in the fields of distributed systems, databases, mobile and wireless communications,
and has more than 30 publications in peerreviewed journals and international proceedings. He has served as a chair and technical
program committee member and reviewer for a number of IEEE and ACM sponsored technical conferences and has received a number
of achievement awards. 相似文献
5.
Performance of different estimators describing propagation of electroencephalogram (EEG) activity, namely: Granger causality, directed transfer function (DTF), direct DTF (dDTF), short-time DTF (SDTF), bivariate coherence, and partial directed coherence are compared by means of simulations and on the examples of experimental signals. In particular, the differences between pair-wise and multichannel estimates are studied. The results show unequivocally that in most cases, the pair-wise estimates are incorrect and a complete set of signals involved in a given process has to be used to obtain the correct pattern of EEG flows. Different performance of multivariate estimators of propagation depending on their normalization is discussed. Advantages of multivariate autoregressive model are pointed out. 相似文献
6.
Majczak A Karbowski M Kamiński M Masaoka M Kurono C Niemczyk E Kedzior J Soji T Knap D Hallmann A Wakabayashi T 《Journal of electron microscopy》2004,53(6):635-647
Effects of jasplakinolide (JSP), a stabilizer of F-actin, and latrunculin A (LTA), a destabilizer of F-actin, on a series of events occurring in the execution phase of staurosporine (STS)-induced apoptotic processes were studied using human osteosarcoma 143B cells. Time-dependent apparent increases of the population of cells with collapsed membrane potential of mitochondria (Delta Psi(m)) caused by STS treatment were not due to actual decreases in the Delta Psi(m) per cell, but due to the fragmentation of cells resulting in decreases in the number of active mitochondria per cell. Decreases in the Delta Psi(m) in fragmented cells occurred late in the execution phase. Both JSP and LAT failed to prevent STS-induced release of cytochrome c from mitochondria followed by the activation of caspases 3 and 9, the cleavage of poly (ADP-ribose) polymerase (PARP) and apoptotic nuclear fragmentation. However, both drugs prevented STS-induced apoptotic cell fragmentation and decreases in the Delta Psi(m). These results indicate that physicochemical states of actin filaments play a certain role in the execution phase of STS-induced apoptotic processes. 相似文献
7.
It is well known that exercise produces analgesic effects (exercise-induced hypoalgesia (EIH)) in animal models and chronic pain patients, but the brain mechanisms underlying these EIH effects, especially concerning the emotional aspects of pain, are not yet fully understood. In this review, we describe drastic changes in the mesocorticolimbic system of the brain which permit the induction of EIH effects. The amygdala (Amyg) is a critical node for the regulation of emotions, such as fear and anxiety, which are closely associated with chronic pain. In our recent studies using neuropathic pain (NPP) model mice, we extensively examined the association between the Amyg and EIH effects. We found that voluntary exercise (VE) activated glutamate (Glu) neurons in the medial basal Amyg projecting to the nucleus accumbens (NAc) lateral shell, while it almost completely suppressed NPP-induced activation of GABA neurons in the central nucleus of the Amyg (CeA). Furthermore, VE significantly inhibited activation of pyramidal neurons in the ventral hippocampus-CA1 region, which play important roles in contextual fear conditioning and the retrieval of fear memory. This review describes novel information concerning the brain mechanisms underlying EIH effects as a result of overcoming the fear-avoidance belief of chronic pain. 相似文献
8.
Kami D Takeda S Itakura Y Gojo S Watanabe M Toyoda M 《International journal of molecular sciences》2011,12(6):3705-3722
Nanoparticle technology is being incorporated into many areas of molecular science and biomedicine. Because nanoparticles are small enough to enter almost all areas of the body, including the circulatory system and cells, they have been and continue to be exploited for basic biomedical research as well as clinical diagnostic and therapeutic applications. For example, nanoparticles hold great promise for enabling gene therapy to reach its full potential by facilitating targeted delivery of DNA into tissues and cells. Substantial progress has been made in binding DNA to nanoparticles and controlling the behavior of these complexes. In this article, we review research on binding DNAs to nanoparticles as well as our latest study on non-viral gene delivery using polyethylenimine-coated magnetic nanoparticles. 相似文献
9.
Channel electrodes are used to characterize the photochemical DISP2 mechanism in respect of the photoelectro-reductions of
- 1. (i) 9,10-diphenylanthracene,
- 2. (ii) benzophenone and
- 3. (iii) 4-fluorobenzophenone.
10.
ABSTRACT A preliminary study aimed at comparing Classical Dynamic Neural Modelling (CDNM) and Hybrid Neural Modelling (HNM) to describe thermal dewatering process in a fluidized bed is presented Two schemes of HN modelling were developed to find the most efficient way of combining a classical mathematical model of the process and Artificial Neural Network (ANN). CDN model was developed using “moving window” technique. In the first scheme of HNM a feed-forward ANN was trained to predict evaporation rate and heat flux in the drying process. In the second scheme of the HN model, ANN was used to determine heat transfer coefficient only. Excellent prediction of drying process by HNM is proved. 相似文献