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991.
This study investigated the effects of screen layout on the usability of a large number of color combination options for customized product. Using an L18 orthogonal array, 18 interfaces were designed around four factors: color display, color name, color formation and alignment. Participants completed a color combination search task and a questionnaire concerning their satisfaction with the interfaces.Based on the search time and user satisfaction, the display of color samples by modular sections (itemized color chips) was found to be the optimal method of color selection. This arrangement reduced the number of combinations of color samples displayed on the screen and allowed efficient navigation of a large palette of color combinations. Vertical alignment aided the product color discrimination and reduced the search time. Users viewed various product color combinations directly with or without the aid of color names.

Relevance to industry

Because of the considerable observed reductions in search time and the superior reported degrees of satisfaction associated with the tested configurations for customized product color combination, the findings of this study have important ramifications for consumers and manufacturers of products as diverse as sofas, curtains, clothing, athletic shoes, cars, mobile phones and the other customized products.  相似文献   
992.
Based on importance measures and fuzzy integrals, a new assessment method for image coding quality is presented in this paper. The proposed assessment is based on two subevaluations. In the first subevaluation, errors on edges, textures, and flat regions are computed individually. The errors are then assessed using an assessment function. A global evaluation with Sugeno fuzzy integral is then obtained based on the importance measure of edge, texture, and flat region. In the second subevaluation, an importance measure is first established depending on the types of regions where errors occur, a subtle evaluation is then obtained using Sugeno fuzzy integral on all pixels of the image. A final evaluation is obtained based on the two subevaluations. Experimental results show that this new image quality assessment closely approximates human subjective tests such as mean opinion score with a high correlation coefficient of 0.963, which is a significant improvement over peak signal-to-noise ratio, picture quality scale, and weighted mean square error, three other image coding quality assessment methods, which have the correlation coefficients of 0.821, 0.875, and 0.716, respectively.  相似文献   
993.
脊波导在传播电磁波的过程中伴随有能量损耗,为了研究填充介质脊波导的衰减特性,本文采用有限元法借助Matlab软件计算了TE模式下部分填充介质倒梯形对称双脊波导的衰减常数和功率容量.分析了脊波导衰减常数和功率容量与脊波导尺寸、工作频率、填充介质相对介电常数之间的关系,给出关系曲线图.这些结果将丰富现有的填充非均匀介质脊波导的数据,为填充介质脊波导的设计和优化提供有价值的依据.  相似文献   
994.
A symbolic procedure is utilized to derive the analytical expressions of the component matrices resulting to the closed-form integration of a stiffness matrix of a hybrid finite element. In order to alleviate the expression growth problem, we employ special techniques, including the use of symmetry conditions, pattern search, and introduction of intermediate variables, so that the final form of the derived stiffness matrix is suitable for coding implementation. Application of the symbolic procedure is made on a hybrid three-dimensional 8-node solid element. The same procedure is equally applicable to other types of hybrid elements.  相似文献   
995.
In this paper, the finite‐time agreement problem of continuous‐time multi‐agent systems with communication delays is considered. First, the multi‐agent system researched in the paper is described. Second, some notations and lemmas used in the paper are given. Then, agreement protocols for continuous (but non‐smooth) multi‐agent systems are proposed, which ensure that the states of agents reach agreement in finite time. The stability analysis and simulations are presented to show the effectiveness of the method. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society  相似文献   
996.
针对目前纯软件实现的IP电话存在的使用不方便等缺陷,设计并实现了一种局域网IP电话系统。文章详细描述了该系统中下位机软件的设计及实现方法,并说明了软件设计中应注意的事项。  相似文献   
997.
We present a hierarchical test methodology for testing a SOC with heterogeneous cores, including the 1149.1-wrapped, P1500-wrapped, and BIST memory cores. We propose an 1149.1-based hierarchical test manager that also provides P1500 test control signals. This scheme includes a memory BIST interface, providing both serial and parallel access ports for BIST circuits. Our approach offers low area and pin overhead, and high flexibility  相似文献   
998.
The serum neutralization (SN) test has been regarded as the “gold standard” for seroconversion following foot-and-mouth disease virus (FMDV) vaccination, although a high-level biosafety laboratory is necessary. ELISA is one alternative, and its format is constantly being improved. For instance, standard polyclonal antisera have been replaced by monoclonal antibodies (MAbs) for catching and detecting antibodies, and inactive viruses have been replaced by virus-like particles (VLPs). To the best of current knowledge, however, no researchers have evaluated the performances of different MAbs as tracers. In previous studies, we successfully identified site 1 and site 2 MAbs Q10E and P11A. In this study, following the established screening platform, the VLPs of putative escape mutants from sites 1 to 5 were expressed and used to demonstrate that S11B is a site 3 MAb. Additionally, the vulnerability of VLPs prompted us to assess another diagnostic antigen: unprocessed polyprotein P1. Therefore, we established and evaluated the performance of blocking ELISA (bELISA) systems based on VLPs and P1, pairing them with Q10E, P11A, S11B, and the non-neutralizing TSG MAb as tracers. The results indicated that the VLP paired with S11B demonstrated the highest correlation with the SN titers (R2 = 0.8071, n = 63). Excluding weakly positive serum samples (SN = 16–32, n = 14), the sensitivity and specificity were 95.65% and 96.15% (kappa = 0.92), respectively. Additionally, the P1 pairing with Q10E also demonstrated a high correlation (R2 = 0.768). We also discovered that these four antibodies had steric effects on one another to varying degrees, despite recognizing distinct antigenic sites. This finding indicated that MAbs as tracers could not accurately detect specific antibodies, possibly because MAbs are bulky compared to a protomeric unit. However, our results still provide convincing support for the application of two pairs of bELISA systems: VLP:S11B-HRP and P1:Q10E-HRP.  相似文献   
999.
To date, the increase in reactive oxygen species (ROS) production for effectual photodynamic therapy (PDT) treatment still remains challenging. In this study, a facile and effective approach is utilized to coat mesoporous silica (mSiO2) shell on the ligand-free upconversion nanoparticles (UCNPs) based on the LiYF4 host material. Two kinds of mesoporous silica-coated UCNPs (UCNP@mSiO2) that display green emission (doped with Ho3+) and red emission (doped with Er3+), respectively, were successfully synthesized and well characterized. Three photosensitizers (PSs), merocyanine 540 (MC 540), rose bengal (RB), and chlorin e6 (Ce6), with the function of absorption of green or red emission, were selected and loaded into the mSiO2 shell of both UCNP@mSiO2 nanomaterials. A comprehensive study for the three UCNP@mSiO2/PS donor/acceptor pairs was performed to investigate the efficacy of fluorescence resonance energy transfer (FRET), ROS generation, and in vitro PDT using a MCF-7 cell line. ROS generation detection showed that as compared to the oleate-capped and ligand-free UCNP/PS pairs, the UCNP@mSiO2/PS nanocarrier system demonstrated more pronounced ROS generation due to the UCNP@mSiO2 nanoparticles in close vicinity to PS molecules and a higher loading capacity of the photosensitizer. As a result, the three LiYF4 UCNP@mSiO2/PS nanoplatforms displayed more prominent therapeutic efficacies in PDT by using in vitro cytotoxicity tests.  相似文献   
1000.
Platinum catalyst for CO oxidation has been studied for decades,due to its high activity and good stability.In this work,we prepared three different lantha num oxide or hydroxide supports(LaOx(OH)y),and deposited platinum(Pt) with 0.5 at% via an impregnation approach to synthesize Pt/LaOx(OH)y catalysts.However,we find that these catalysts perform a poor stability for the CO oxidation reaction.The fresh and used samples were comprehensively characterized by multiple techniques including power X-ray diffraction(XRD),X-ray absorption fine structure(XAFS),transmission electron microscopy(TEM),temperature-programmed reduction by carbon monoxide(CO-TPR) and thermogravimetric analysis(TGA),to demonstrate that the oxidized platinum atoms or clusters,without any component of Pt-Pt metallic bond,are highly dispersed on the surface of LaOx(OH)y.Furthermore,the as-formed lanthanum carbonate(La2O2CO3) during the exposure to ambient circumstances or in the reaction atmosphere of CO+O2,severely impair the reactivity of Pt/LaOx(OH)y.On the basis of the obtained experimental results,we have drawn a conclusion that the oxidized PtOx atoms or PtxOy clusters are the active species for CO oxidation,while the formation of lanthanum carbonate is the origin of deactivation on reactivity.  相似文献   
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