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991.
992.
993.
Behavioral cues to deception are instrumental in detecting deception. As one of the primary sources of deception behavior, text has been analyzed at the level of sub-sentence or message but not the discourse of interaction. Additionally, empirical studies on cues to deception in the case of multiple receivers remain nonexistent. To fill these voids, we propose a discourse framework and six hypotheses about deception behaviors in a multi-receiver environment. The deception behaviors are operationalized by discourse features based on an analysis of real-world data. The results of statistical analysis validate the efficacy of discourse features in discriminating deceivers from truth-tellers. 相似文献
994.
Traditional methods based on the product of exponentials (POE) formula are parametrically continuous and complete for the calibration of the kinematic parameters of serial robots. However, these methods are not minimal due to the constraints of joint twists. This paper puts forward a new POE-based model, whose parameters are totally independent and conform to the formula of minimality. This is the first model that simultaneously satisfies the requirements of parametric continuity, completeness, and minimality with uniform and generic modeling rules. The proposed approach avoids the operations of normalization and orthogonalization which are necessary redundancy elimination steps with the traditional model. Simulations on a SCARA robot and experiments on an ABB IRB 120 robot prove that the new model outperforms in convergence, accuracy, and efficiency. 相似文献
995.
介绍粉煤灰混凝土多孔砖生产的原材料选择、粉煤灰性能、混合料处理、坯体成型与养护等工艺技术及其利废节能的优越性. 相似文献
996.
汽车用塑料注塑新技术的进展 总被引:1,自引:0,他引:1
综述了汽车用塑料的注射成型技术的进展,简单介绍了气体辅助注射成型(GAIM)、水辅助注射成型、熔芯注射成型、反应注射/增强反应注射(RIM/RRIM)成型等技术的特点、生产的汽车部件及最新动向。 相似文献
997.
Solutions of rare earth modifier (RES) and epoxy chloropropane (ECP) grafting modification method were used for the surface treatment of aramid fiber. Tensile properties of both the aramid/epoxy composites and single fibers were tested. The effects of RES concentration on tensile properties of aramid/epoxy composites were investigated in detail to explore an optimum amount of rare earth elements in solution for modifying aramid fiber. The fracture surface morphologies of tensile specimens were observed and analyzed with the aid of SEM. The experimental results show that rare earth treatment is superior to ECP grafting treatment in promoting interfacial adhesion between the aramid fiber and epoxy matrix. Meanwhile, the tensile strengths of single fibers were almost not affected by RES treatment. The optimum performance is obtained when the content of rare earth elements is 0.5 wt %. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1037–1041, 2004 相似文献
998.
In the present study, the stability condition for semi-discrete difference schemes of hyperbolic conservation laws obtained from Fourier analysis is simplified. This stability condition can be applied only to linear difference schemes with constant coefficients implemented with periodic boundary treatment. It could often give useful results for other cases, such as schemes with variable coefficients, schemes for nonperiodic problem and nonlinear problem. However, this condition usually leads to a trigonometric inequality, which makes it not convenient to use. For explicit difference schemes on uniform grids, this trigonometric inequality can be converted to polynomial form. Furthermore, if the scheme is a high-order one, the polynomial can be factorized into a simple form. Thus, it is much easier to solve than the inequality obtained directly from Fourier analysis. For compact difference schemes and conservative schemes, similar results are obtained. Some applications of this new stability criterion are shown, including judging the stability of two schemes, proving the upstream central schemes to be stable, constructing a stable upwind dissipation relation preserving (DRP) scheme and constructing an optimized weighted essentially non-oscillatory (WENO) scheme. Since WENO schemes are nonlinear schemes, the stability analysis in the present study is performed on their underlying linear schemes. According to the numerical tests, the underlying linear scheme should be stable, otherwise the corresponding WENO scheme may display instability. These applications demonstrate that this criterion is convenient and efficient for judging the linear stability of semi-discrete difference schemes and constructing stable upwind difference schemes. 相似文献
999.
Optimization of reduction potential for electroseparation was studied for the recovery of gold, copper, and lead from acidic
solution. A linear sweep voltammetric method enabled us to determine characteristic reduction potentials for each metal and
the kinetics of the metal deposition indicated by current-voltage curves. In order to precipitate the metal species sequentially,
reduction potentials were examined for the individual and mixed solutions of Au(III), Cu(II), and Pb(II). The three metals
were reasonably well isolated from the mixed solutions such as Cu(II)/ Pb(II) and Au(III)/Cu(II)/Pb(II) in the order of the
corresponding reduction potentials, in particular, the mass transfer controlled reduction potentials, obtained from linear
sweep voltammetry (LSV) measurement. 相似文献
1000.
本文阐述了折流杆换热器CAD系统的开发方法,包括:把大量线图、数表进行数据程序化,利用ADSRX技术、PDB界面设计技术和参数化图形设计技术对折流杆换热器的一百多种类型、三万多种规格的零部件进行了设计,将数据信息采用数据文件和数据库的方式进行了集成和管理,从而实现折流杆换热器工艺、机械、零部件子系统的集成。 相似文献