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51.
Fully human antibodies have minimal immunogenicity and safety profiles. At present, most potential antibody drugs in clinical trials are humanized or fully human. Human antibodies are mostly generated using the phage display method (in vitro) or by transgenic mice (in vivo); other methods include B lymphocyte immortalization, human–human hybridoma, and single-cell polymerase chain reaction. Here, we describe a structure-based computer-aided de novo design technology for human antibody generation. Based on the complex structure of human epidermal growth factor receptor 2 (HER2)/Herceptin, we first designed six short peptides targeting the potential epitope of HER2 recognized by Herceptin. Next, these peptides were set as complementarity determining regions in a suitable immunoglobulin frame, giving birth to a novel anti-HER2 antibody named “HF,” which possessed higher affinity and more effective anti-tumor activity than Herceptin. Our work offers a useful tool for the quick design and selection of novel human antibodies for basic mechanical research as well as for imaging and clinical applications in immune-related diseases, such as cancer and infectious diseases.  相似文献   
52.
This paper is devoted to analytical modeling of apparent wind load effects on a tether constraining a power kite performing a fast crosswind motion. The refined crosswind motion law generalized for accounting the kite control is derived in the case of equilibrium motion of the kite. The paper also presents the study of the effect of tether sag based on the mathematical model of a gently sloping tether line.  相似文献   
53.
《Ergonomics》2012,55(10):1373-1394
Measurements of vessel motion and consequent seasickness amongst passengers have been made on six ships, two hovercraft and a hydrofoil. Data are presented for 20 029 passengers surveyed on 114 voyages involving 370?hours of motion recordings. Vomiting incidence and illness rating were found to be linearly related to the root-mean-square magnitude of the vertical z-axis acceleration. Sickness increased with increasing duration of exposure and a measure of motion ‘dose’ is examined as a convenient way of combining the variables of stimulus magnitude and duration. High frequency motion in hovercraft at about 0·6?Hz was found to be less provoking of sickness than similar magnitudes at lower frequencies. Motion in axes other than the vertical correlated less highly with sickness, although there was some intercorrelation between axes. The results presented enable predictions to be made of seasickness occurrence in marine vessels and other forms of transport where low frequency vertical oscillations are encountered.  相似文献   
54.
《Ergonomics》2012,55(9):1958-1972
In designing a workstation, computer-aided human modelling programs can be used advantageously to analyse human-fit to the workstation components. The analysis is performed within a three-dimensional computer graphics environment. To illustrate the current state of development, six representative programs were selected: CYBERMAN, COMBIMAN, CREW CHIEF, JACK, SAMMIE, and MANNEQUIN. The programs differ considerably in terms of system requirement, operating characteristics, applicability and the various ergonomic evaluation functions available in the human modelling programs. The comparative analysis of the programs will aid the user to select the appropriate program for a particular workstation design.  相似文献   
55.
《Ergonomics》2012,55(12):1730-1738
Abstract

Two computer vision algorithms were developed to automatically estimate exertion time, duty cycle (DC) and hand activity level (HAL) from videos of workers performing 50 industrial tasks. The average DC difference between manual frame-by-frame analysis and the computer vision DC was ?5.8% for the Decision Tree (DT) algorithm, and 1.4% for the Feature Vector Training (FVT) algorithm. The average HAL difference was 0.5 for the DT algorithm and 0.3 for the FVT algorithm. A sensitivity analysis, conducted to examine the influence that deviations in DC have on HAL, found it remained unaffected when DC error was less than 5%. Thus, a DC error less than 10% will impact HAL less than 0.5 HAL, which is negligible. Automatic computer vision HAL estimates were therefore comparable to manual frame-by-frame estimates.

Practitioner Summary: Computer vision was used to automatically estimate exertion time, duty cycle and hand activity level from videos of workers performing industrial tasks.  相似文献   
56.
Primary accelerometer calibration is carried out under the assumption that a vibration exciter gives a rectilinear motion to an accelerometer to be calibrated. However practical vibration given by the vibration exciter includes parasitic motion such as transverse, rocking, and bending motion. Such parasitic motion would give two serious effects on primary calibration results, transverse motion effect and vibration distribution effect. Transverse motion effect is caused by an inner product of the vectors of both transverse motion and transverse sensitivity. On the other hand, the vibration distribution effect is caused by relative motion between a sensing point of accelerometer and a spot sensed by the interferometer. As these effects have close interaction between parasitic motion and measuring instruments, it would be very difficult to evaluate them by measuring independently each component.  相似文献   
57.
李玥  勒世清  陈德芳 《激光杂志》2021,42(3):179-183
为了解决传统方法容易受到噪声、光照等因素影响,导致目标检测精度与标刻效果降低的问题,在考虑目标运动状态基础上提出一种激光在线跟踪标刻方法.首先根据激光点构建对应运动模型,并通过迭代计算求解获取出目标运动激光点和实际像素坐标,实现激光对实际目标的自主瞄准,并得出目标运动粗略范围;使用改进粒子滤波法进一步精细定位,由此计算...  相似文献   
58.
ISAR成像系统与技术发展综述   总被引:1,自引:0,他引:1  
高分辨率雷达可以对非合作目标进行远距离二维成像,其在战略防御、反卫星、战术武器以及雷达天文学等方面都有重要的应用价值。文中首先介绍了国外典型的地基雷达、舰载雷达、机载雷达成像系统,接着阐述了各种逆合成孔径雷达(ISAR)运动补偿、成像技术以及不同ISAR成像技术的应用范围和发展现状。最后对雷达成像技术发展中应进一步研究的问题进行了展望。  相似文献   
59.
Taking fully into consideration the fact that one human action can be intuitively considered as a sequence of key poses and atomic motions in a particular order, a human action recognition method using multi-layer codebooks of key poses and atomic motions is proposed in this paper. Inspired by the dynamics models of human joints, normalized relative orientations are computed as features for each limb of human body. In order to extract key poses and atomic motions precisely, feature sequences are segmented into pose feature segments and motion feature segments dynamically, based on the potential differences of feature sequences. Multi-layer codebooks of each human action are constructed with the key poses extracted from pose feature segments and the atomic motions extracted from motion feature segments associated with each two key poses. The multi-layer codebooks represent action patterns of each human action, which can be used to recognize human actions with the proposed pattern-matching method. Three classification methods are employed for action recognition based on the multi-layer codebooks. Two public action datasets, i.e., CAD-60 and MSRC-12 datasets, are used to demonstrate the advantages of the proposed method. The experimental results show that the proposed method can obtain a comparable or better performance compared with the state-of-the-art methods.  相似文献   
60.
We propose an efficient scheme for camera motion characterization in MPEG‐compressed video. The proposed scheme detects six types of basic camera motions through threshold‐based qualitative interpretation, in which fixed thresholds are applied to motion model parameters estimated from MPEG motion vectors (MVs). The efficiency and robustness of the scheme are validated by the experiment with real compressed video sequences.  相似文献   
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