基于视频的现实人物运动创作

提出一种根据用户指定的人体运动和观察视角生成真实感视频的方法.首先采集演员进行少数基本运动时的多视角视频数据库,并使用无标记运动捕捉的方法获得任意时刻人体对应的骨骼和3D模型.其次,用户对人体骨架指定运动并设定视角,以此定义目标视频.实验结果验证了文中方法能够利用有限的数据库合成演员在用户指定运动和视角下的真实感视频.     

基于GIS的黑龙江省多年平均降水量空间插值分析比较

以黑龙江省分辨率为90m的数字高程模型(DEM)的数据为基础,结合ArcGIS软件,分析黑龙江省83个气象站点1971—2018年的降水资料,采用克里金法(Kriging)、反距离权重法(IDW)、径向基函数法(RBF)、全局多项式插值法(GPI)和趋势面法(TS)五种方法进行空间插值模拟.结果表明,黑龙江省年平均降水量东多西少,具有自边缘到中心逐渐增加的特征.西南部和西北部(漠河和北极村)的降水量大多在500mm以下,部分中部地区的降水量超过700mm.总体年平均降水量在400mm—700mm之间,大部分地区属于半湿润区.在该研究区域中,通过克里金指数模型插值方法获得结果的准确性优于其他插值方法.     

Maximizing learning without sacrificing the fun: Stealth assessment,adaptivity and learning supports in educational games

In this study, we investigated the validity of a stealth assessment of physics understanding in an educational game, as well as the effectiveness of different game-level delivery methods and various in-game supports on learning. Using a game called Physics Playground, we randomly assigned 263 ninth- to eleventh-grade students into four groups: adaptive, linear, free choice and no-treatment control. Each condition had access to the same in-game learning supports during gameplay. Results showed that: (a) the stealth assessment estimates of physics understanding were valid—significantly correlating with the external physics test scores; (b) there was no significant effect of game-level delivery method on students' learning; and (c) physics animations were the most effective (among eight supports tested) in predicting both learning outcome and in-game performance (e.g. number of game levels solved). We included student enjoyment, gender and ethnicity in our analyses as moderators to further investigate the research questions.     

网络法律浅析

随着当今网络技术的迅猛发展,人们的行为和生活越来越受到其影响,发生着改变,故调整其行为规范的网络相关法律法规也越来越受到人们的关注。从法理学角度出发对网络法律进行构建与研究,在此基础上规范其基本理念和适用原则,对于建立完善网络法律体系尤为重要。本文从法理学角度出发,对网络法律的基本理念和原则进行了简要探析。     

Collective modes and a theory of response ofd-wave superconductors

We present a theory of the response ofd-wave superconductors to weak applied fields, by taking account of the Coulomb interaction and all the collective degrees of freedom as well as crystal symmetry. We choose two representative phases: the d phase, which has point nodes in the energy gap, and theY _2–1 phase, which has line as well as point nodes. The former is a self-consistent solution for cubic as well as spherical symmetries and the latter is one for spherical, cubic, and hexagonal symmetries. We obtain obviously gauge-invariant expressions for the order-parameter fluctuations and the currents, having forms common not only to thed-wave states, but also to thep-wave states studied earlier. We also investigate the collective excitations; in the long-wavelength limit for spherically symmetric systems, there are, on the frequency-temperature plane, seven branches for eachd-wave phase considered, in addition to the common plasma mode and orbital Goldstone modes resulting from the spontaneous breakdown of the rotational invariance. In theY _2–1-phase two eigenmodes are found to become gapless at a finite temperature, below which they are purely imaginary. This implies instability of the phase. The effect of crystal anisotropy on the collective spectra is also studied.A preliminary report on the present work was published inJpn. J. Appl. Phys. Suppl. 26-3, 167 (1987).     

Analysis of weakly guiding cladded acoustic fibers of hexagonal crystal symmetry

An approximate analysis of the weakly guiding cladded acoustic fiber consisting of a core and infinite thick cladding both with hexagonal crystal symmetry is presented. The crystalline Z axis is parallel to the fiber axis. Weak guidance conditions require that the stiffness constants of the core are slightly less than those of the cladding, and the density of the core and cladding are almost the same. Approximate dispersion and cutoff equations are derived for all pure guided modes. Dispersion curves of several lower-order guided torsional, radial-axial and flexural modes are evaluated using both exact and approximate formulas and they are in good agreement. A simple approximate dispersion equation for leaky (longitudinal-type) modes is also obtained.     

Intermediate temperature solid oxide fuel cell based on fully integrated plasma-sprayed components

This work addresses the fabrication of membrane-type solid oxide fuel cells (SOFCs) operating at medium temperatures, where all components are fabricated by plasma spray technology, and the evaluation of the performance of the SOFC single unit in a temperature range of 500 to 800 °C. Single cells composed of LaSrMgO₃ cathodes, LaSrGaMgO₃ (LSGM) electrolytes, and Ni/yttria-stabilized zirconia anodes were fabricated in successive atmospheric plasma-spraying processes. Plasma-spraying processes have been optimized and tailored to each layer to achieve highly porous cathode and anode layers as well as high-density electrolyte layers. A major effort has been devoted to the production of the LSGM electrolyte that has a high density and is free of cracks. Electrochemical impedance spectroscopy was used to investigate the conductivity of the electrode layers, and particularly the resistance of the electrolyte layer. It revealed that the heat treatment had a great influence on the specific conductivity of the sprayed electrolyte layers and that the specific conductivity of the heat-treated layers was dramatically increased to the same magnitude as is typical for sintered LSGM pellets. The experimental results have demonstrated that the plasma-spraying process has a great potential for the integrated fabrication of medium-temperature SOFC units. The original version of this article was published as part of the ASM Proceedings, Thermal Spray 2003: Advancing the Science and Applying the Technology, International Thermal Spray Conference (Orlando, FL), May 5–8, 2003, Basil R. Marple and Christian Moreau, Ed., ASM International, 2003.     

The T Cell Repertoires from Nickel Sensitized Joint Implant Failure Patients

Nickel (Ni²⁺) is one of the most common allergens, affecting around 10–15% of the general population. As the demand for orthopedic implant surgery rises, the number of surgical revisions due to joint implant failure also increases. There is evidence that some patients develop joint failure due to an immune response to a component of the implant, and we have found that Ni²⁺ is an especially important cause. Hence, understanding the mechanisms by which Ni²⁺ allergy induces joint implant failure becomes a critical research question. The structural basis of Ni²⁺ activation of pathogenic T cells is still not clear. The purpose of this study was to characterize Ni²⁺-reactive T cell repertoires derived from the peripheral blood of joint failure patients due to Ni²⁺ sensitization using single-cell sequencing techniques. We stimulated the proliferation of Ni²⁺ -reactive T cells from two implant failure patients in vitro, and sorted them for single-cell VDJ sequencing (10× genomics). We identified 2650 productive V-J spanning pairs. Both TCR α chains and β chains were enriched. TRBV18 usage is the highest in the P7 CD4+ population (18.1%), and TRBV5-1 usage is the highest in the P7 CD8+ population (12.1%). TRBV19 and TRBV20-1 segments are present in a high percentage of both P7 and P9 sequenced T cells. Remarkably, the alpha and beta chain combination of TRAV41-TRBV18 accounts for 13.5% of the CD4+ population of P7 patient. Compared to current Ni specific T cell repertoire studies of contact dermatitis, the Vα and Vβ usages of these joint implant failure patients were different. This could be due to the different availability of self-peptides in these two different tissues. However, TRBV19 (Vβ17) was among frequently used TCR β chains, which are common in previous reports. This implies that some pathogenic T cells could be similar in Ni²⁺ hypersensitivities in skin and joints. The alignment of the TCR CDR3β sequences showed a conserved glutamic acid (Glu) that could potentially interact with Ni²⁺. The study of these Ni²⁺ specific TCRs may shed light on the molecular mechanism of T cell activation by low molecular weight chemical haptens.     

致密油藏直井多层缝网压裂产量递减分析

垂向多层发育的致密油藏常采用缝网压裂进行开采,从而改善储层渗透率,提高油井产量。为此建立直井多层缝网压裂不稳定渗流数学模型,压裂后各层划分为人工裂缝区、改造区和未改造区。绘制分析Blasingame产量递减典型曲线,曲线分为7个流动阶段,总裂缝长度一定时,裂缝半长短的储层流体渗流率先到达未改造区,流体渗流阻力大,Blasingame曲线靠下;总改造体积一定时,各层改造体积差异越大,Blasingame曲线越靠下。用所建立的模型,对实测生产资料进行解释,获得各层裂缝半长、改造区渗透率等相关地层参数,该模型对进行多层缝网压裂直井产量分析具有指导意义。     

基于Windows的液压实时测试浅析

本文通过分析WINDOWS实时处理的局限性，提出了解决问题的几种机制；同时以液压元件的实时测试中断程序的实现为例说明了机制的应用，研究表明，这种机制较传统方法实用、有效。