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2011年无线通信与信号处理国际会议(WCSP 2011)

作者： Osamu MUTA Center for Japan-Egypt Cooperation in Science and Technology Graduate School of Information Science and Electrical Engineering Kyushu University 744 Motooka Nishi-ku Fukuoka-shi Fukuoka-ken 819-0395 Japan

As a solution to high peak-to-average power ratio (PAPR) problems in vector coding (VC) systems, phase control based methods such as selected mapping and partial transmit sequence have been investigated. In this paper, a phase sequence blind estimation method is presented for PAPR reduction based on phase control in multi-input multi-output (MIMO) adaptive modulated vector coding systems, where Turbo code is employed. On the receiver side, the phase sequence component is estimated using a maximum likelihood method which selects the most likelihood sequence among all candidate ones by exploiting softoutput information of the decoder. Computer simulation results show that when the number of candidate sequences in SLM is .. = 16, instantaneous power of the transmit signal at the CCDF of 10.6 can be reduced by about 4.5dB and 3.4dB for SISO and MIMO cases as compared to case without PAPR reduction, while almost the same block error rate (BLER) performance and the same throughput performance as case of the prefect phase sequence estimation are achieved in attenuated 6-path Rayleigh fading condition.

关键词： vector coding Peak-to-average power ratio (PAPR) PAPR reduction MIMO Turbo coding.

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Roundhouse Kick's TEAKWONDO Variability in Kinematic Coupling Assessed by Continuous Relative Phase and vector coding

Roundhouse Kick's TEAKWONDO Variability in Kinematic Couplin...

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Iranian Conference on Biomedical Engineering

作者： H. R. Barnamei M. R. Kharazi School of Biomedical Engineering Islamic Azad University of Science and Research Branch

ISBN: (纸本)9781467393522

This study aimed to investigate the kicking limb coordinative patterns adopted by Taekwondo practitioners (Taek-wondoka) during a roundhouse kick (Ap Dollio Chagi). Six Taekwondoka performed five repetitions of both kicks while kicking limb kinematics were recorded using a motion analysis system. Lower-limb coordination was quantified for hip and knee flexionextension from toe-off to kick completion, using the Continuous relative phase (CRP). For all trials, across all participants, CRP curve peaks and maximum and minimum were determined. The CRP analysis highlighted, during the central portion of both kicks, a delayed flexion of the hip with respect to the knee. Our findings suggested that there was a slight difference in the pattern and variability of inter-joint coordination presented by CRP. This difference may be caused by the velocity (temporal evolution) and the normalization procedure involved in calculating CRP.

关键词： Taekwondo VICON vector coding Motion Analysis

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Analysing patterns of coordination and patterns of control using novel data visualisation techniques in vector coding

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Foot 2020年 44卷 101678-101678页

作者： Needham, Robert A. Naemi, Roozbeh Hamill, Joseph Chockalingam, Nachiappan Centre for Biomechanics and Rehabilitation Technologies Staffordshire University Leek Road Stoke on Trent ST4 2DF United Kingdom School of Public Health and Health Sciences University of Massachusetts Amherst 30 Eastman Lane Amherst 01003 MA United States

Objective: vector coding is a non-linear data analysis technique that quantifies inter-segmental coordination and coordination variability. The traditional approach of reporting time-series data from vector coding can be problematic when overlaying multiple trials on the same illustration. The objective of this study was to describe and present novel data visualisations for displaying the coordination pattern, segmental dominancy, range of motion on an angle–angle diagram, and coordination variability. This allows for a comparison of data across multiple participants with a focus on single subject analysis. Methods: Novel data visualisation techniques that involve the use of colour and data bars to map and profile coordination pattern and coordination variability data. The introduction and profiling of inter-data point range of motion quantifies range of motion of the dominant segment on an angle-angle plot and illustrates patterns of movement control. As an example, the dataset used the Istituto Ortopedico Rizzoli foot model to describe rearfoot-forefoot and shank-foot coordination during stance. Results: The use of colour mapping provides the option to inspect an entire dataset and to compare data across multiple participants, groups, and segment couplings. Combining coupling angle mapping with segmental dominancy profiling offers an intuitive and instant summary on coupling angle distribution. The novel inclusion of inter-data point range of motion profiling provides meaning to the interpretation of segmental dominancy data and demonstrates distinct patterns of movement control. Conclusions: The use of colour mapping and profiling techniques highlighted differences in coordination pattern and coordination variability data across several participants that questions the interpretation and relevance of reporting group data. Colour mapping and profiling techniques are ideal reporting methods to compliment prospective multiple single-subject design studies and to clas

关键词： Coordination Coupling angle mapping Segmental dominancy profiling Variability vector coding

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LOW-COMPLEXITY vector SOURCE coding FOR DISCRETE LONG SEQUENCES WITH UNKNOWN DISTRIBUTIONS 49

LOW-COMPLEXITY VECTOR SOURCE CODING FOR DISCRETE LONG SEQUEN...

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49th IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP)

作者： Woldemariam, Leah Liu, Hang Scaglione, Anna Cornell Univ Dept Elect & Comp Engn Cornell Tech Ithaca NY 14850 USA

ISBN: (纸本)9798350344868;9798350344851

In this paper, we propose a source coding scheme that represents data from unknown distributions through frequency and support information. Existing encoding schemes often compress data by sacrificing computational efficiency or by assuming the data follows a known distribution. We take advantage of the structure that arises within the spatial representation and utilize it to encode run-lengths within this representation using Golomb coding. Through theoretical analysis, we show that our scheme yields an overall bit rate that nears entropy without a computationally complex encoding algorithm and verify these results through numerical experiments.

关键词： Data compression run-length coding vector coding bit analysis

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Partial Scrambling PAPR Reduction for Multi-Code vector coding in Adaptive Modulated MIMO Systems

Partial Scrambling PAPR Reduction for Multi-Code Vector Codi...

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International OFDM Workshop

作者： Osamu MUTA Center for Japan-Egypt Cooperation in Science and Technology Kyushu University

ISBN: (纸本)9783800733606

Multi-Input Multi-Output (MIMO) vector coding (VC) transmission with adaptive modulation is an effective technique to enhance transmission performance in frequency selective wireless channels. The VC is a kind of code-division multiplexing (CDM) by which eigenvectors of channel autocorrelation matrix are used as spreading code. A major disadvantage of the VC is that the transmit signal exhibits high peak-to average power ratio (PAPR), which causes nonlinear distortion and/or power efficiency degradation at a power amplifier, similarly to OFDM and CDM systems. As a solution to this problem, selected mapping (SLM) PAPR reduction techniques have been studied. This paper presents a partial scrambling SLM PAPR reduction method for multi-code VC transmission in adaptive modulated MIMO systems. In this method, PAPR of the transmit signal is reduced to scramble bit sequence mapped on limited number of code vectors in VC systems. In addition, the maximum amplitude of transmit signal in each transmission block is reduced only when the maximum peak amplitude exceeds a given threshold value. Simulation results clarify that the partial scrambling method achieves better average throughput performance than the conventional method, although almost identical PAPR reduction performance is obtained for MIMO VC systems in an attenuated six-path Rayleigh fading condition.

关键词： vector coding Peak-to-average power ratio (PAPR) PAPR reduction MIMO

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Fatigue-induced modifications to trunk and lower-limb coordination mode during drop vertical jump and sidestep cutting tasks in female handball athletes

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GAIT & POSTURE 2025年 117卷 45-53页

作者： Pereira, Dayanne R. Moura, Felipe A. Moraes, Renato Lopes, Ana Luiza de C. Mochizuki, Luis Santiago, Paulo R. P. Bedo, Bruno L. S. Univ Sao Paulo Sch Phys Educ & Sport Lab Technol & Sport Performance Sao Paulo Brazil Univ Estadual Londrina Sport Sci Dept Lab Appl Biomech Londrina Brazil Univ Sao Paulo Sch Phys Educ & Sport Ribeirao Preto Biomech & Motor Control Lab Ribeirao Preto Brazil Univ Estadual Campinas Fac Phys Educ Campinas SP Brazil Univ Sao Paulo Sch Arts Sci & Humanities Sao Paulo Brazil

Background: Examining movement patterns in athletic activities is crucial for understanding the mechanisms and contributing factors linked to lower limb injuries, with the knee joint being particularly vulnerable in team sports like handball. Research question: How does a handball-specific fatigue protocol affect trunk-knee and hip-knee intersegmental coordination during the drop vertical jump (DVJ) and sidestep cutting maneuver (SCM) in handball players? Methods: Twenty female handball athletes participated, performing three trials of each task before and after undergoing the fatigue protocol. Using a motion capture system, the trunk, hip, and knee joint angles were recorded in all three planes and time-normalized to 100% of the stance phase. A vector coding technique evaluated coordination nodes. Results: This study indicated significant post-fatigue alterations in coordination modes, especially in the sagittal plane for DVJ and SCM tasks. There was an increase in knee phase modes and a decrease in in-phase modes for hip-knee coordination during the DVJ task, with transverse plane coordination being affected only in the SCM task. Movement variability decreased in the frontal and transverse planes post-fatigue, suggesting a neuromuscular strategy to simplify task execution. Significance: Fatigue's significant impact on movement coordination and variability. It demonstrates the importance of considering the specificity of the task performed when setting up injury prevention training to mitigate the negative effects of fatigue and reduce the risk of injuries.

关键词： Fatigue Coordination vector coding Handball Sidestep cutting Drop vertical jump

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Knee coordination during landing in ballet-trained female dancers and non-dancers

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JOURNAL OF BIOMECHANICS 2025年 185卷 112684-112684页

作者： Williams, Leah E. Dennis, Justin D. Pamukoff, Derek N. Western Univ Sch Kinesiol 1151 Richmond St London ON N6A 3K7 Canada Univ Waterloo Dept Kinesiol & Hlth Sci Waterloo ON Canada Univ North Carolina Dept Exercise & Sports Sci Chapel Hill NC USA

Dance is a prevalent activity in females who are at a greater risk for traumatic knee injuries compared with males. However, dancers have a lower injury incidence than other athletes, and landing techniques obtained from training may limit accessory frontal plane movement. Frontal and sagittal plane kinematics, kinetics, and knee coordination patterns were compared between 18 ballet-trained female dancers and 18 non-dancers throughout the landing phase of a drop vertical jump. Dancers landed with greater peak knee flexion (-113.23 f 15.1 degrees vs. -99.3 f 16.2 degrees;p = 0.013, d = 0.890) and lower peak knee abduction (-1.15 f 4.28 degrees vs. -7.26 f 6.26 degrees;p = 0.002, d = 1.145) compared with controls. Dancers had smaller external knee flexion moments (0.14 f 0.02 vs. 0.17 f 0.05 BWxHt, p = 0.043, d = 0.702), smaller peak external knee abduction moments (0.024 f 0.011 vs. 0.0036 f 0.014 BWxHt, p = 0.046, d = 0.680), and smaller peak vertical ground reaction force (1.57 f 0.22 vs. 1.92 f 0.43 BW, p = 0.005, d = 1.008) compared with controls. Dancers also utilized a coordination pattern that included less in-phase motion (p < 0.001) between the sagittal and frontal knee coupling and more exclusive shank motion (p = 0.027) between the thigh and shank in the frontal plane compared with controls. There were no differences between the groups in exclusive sagittal plane (p = 0.386), exclusive frontal plane (p = 0.708), or anti-phase (p = 0.443) motion between the sagittal and frontal knee coupling compared with controls. Dancers undergo extensive landing training, which may contribute to less frontal plane knee motion. As such, dancers' ability to flex the knee without additional and simultaneous knee abduction during landing may help to mitigate their acute knee injury risk.

关键词： Joint coordination vector coding Dancers Knee abduction

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Exertion and pain do not alter coordination variability in runners with iliotibial band syndrome

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CLINICAL BIOMECHANICS 2017年 47卷 73-78页

作者： Hafer, Jocelyn F. Brown, Allison M. Boyer, Katherine A. Univ Massachusetts Dept Kinesiol Amherst MA 01003 USA Rutgers State Univ Sch Hlth Profess Dept Rehabil & Movement Sci Newark NJ USA

Background: Iliotibial band syndrome is a common overuse running injury which results in altered mechanics. While injuries alter discrete mechanics, they may also cause a change in coordination variability, the stride-to stride organization of runners' movement patterns. Uninjured and injured runners may experience a change in coordination variability during a run to exertion due to fatigue, pain, or a combination of these factors. The aim of the current study was to determine if runners with iliotibial band syndrome and uninjured runners display different segment coordination variability across the course of a run to exertion. Methods: 3D kinematics were collected as 13 uninjured runners and 12 runners with iliotibial band syndrome ran on a treadmill. A modified vector coding technique was used to calculate coordination variability during stance for segment couples of interest. Coordination variability was compared between uninjured and injured runners at the beginning and end of the run. The influence of pain on coordination variability was also examined. Findings: There were no differences in coordination variability at the beginning or end of the run between uninjured runners and those with iliotibial band syndrome. The change in coordination variability due to the run was not different between uninjured runners, injured runners who experienced no change in pain, and injured runners who did experience a change in pain. Interpretation: Runners do not constrain the patterns of segment motion they use in response to exertion nor does it appear that occurrence of pain during running results in a differential change in coordination variability.

关键词： Dynamical systems analysis vector coding Running injury

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Influence of Previous Iliotibial Band Syndrome on Coordination Patterns and Coordination Variability in Female Runners

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JOURNAL OF APPLIED BIOMECHANICS 2019年第5期35卷 305-311页

作者： Foch, Eric Milner, Clare E. Cent Washington Univ Dept Hlth Sci Ellensburg WA 98926 USA Drexel Univ Dept Phys Therapy & Rehabil Sci Philadelphia PA 19104 USA

It is unknown if female runners who have sustained multiple iliotibial band syndrome occurrences run differently compared with runners who developed the injury once or controls. Therefore, the purpose of this study was to determine if differences existed in coordination patterns and coordination variability among female runners with recurrent iliotibial band syndrome, 1 iliotibial band syndrome occurrence, and controls. Overground running trials were collected for 36 female runners (n = 18 controls). Lower extremity coordination patterns were examined during running via a vector coding analysis. Coordination variability was calculated via the ellipse area method. Separate 1-way (group) Kruskal-Wallis tests were performed to compare each coordination pattern and coordination variability. Lower extremity coordination between frontal plane hip-transverse plane hip, frontal plane pelvis-frontal plane thigh, and frontal plane thigh-transverse plane shank was similar among groups and so may not be related to the risk of iliotibial band syndrome. Runners with 1 iliotibial band syndrome occurrence demonstrated greater coordination variability for 2 of 3 couplings compared with both controls and runners with recurrent iliotibial band syndrome. Thus, the number of previous injury episodes may influence coordination variability in female runners with a history of iliotibial band syndrome.

关键词： vector coding overuse injury hip pelvis thigh

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Combination Suicide Gene Delivery with an Adeno-Associated Virus vector Encoding Inducible Caspase-9 and a Chemical Inducer of Dimerization Is Effective in a Xenotransplantation Model of Hepatocellular Carcinoma

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BIOCONJUGATE CHEMISTRY 2019年第6期30卷 1754-1762页

作者： Khan, Nusrat Bammidi, Sridhar Chattopadhyay, Sourav Jayandharan, Giridhara R. Indian Inst Technol Dept Biol Sci & Bioengn Kanpur 20816 Uttar Pradesh India

Current treatment approaches for hepatocellular carcinoma (HCC) have a narrow therapeutic index and alternate modes of treatment are thus required. We have utilized a gene delivery vector containing inducible caspase 9 (iCasp9) gene, which is a synthetic analogue based on the mammalian caspase 9 and fused to a human FK506 binding protein that allows its conditional dimerization to a synthetic, small molecule [chemical inducer of dimerization, AP20187] and results in target cell apoptosis. In our studies, we have tested these synthetic vectors based on an adeno-associated virus platform for their potential anti-tumorigenic effect in human HCC cells in vitro and in a HCC tumor model developed in nude mice. Our data demonstrates that the iCasp9-AP20187 bioconjugate is able to trigger terminal effectors of cellular apoptosis and presents a viable approach for the potential treatment of HCC.

关键词： vector coding Gene transfer Nude Mice Adeno-Associated Virus Heterologous Transplantation composite vector Caspase 9 Viral vector suicide gene Hepatocellular Cancer Genetic Therapy CASP9 gene dimerization Target cells Human-centered computing

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