取代酚对日本长腿蛙蝌蚪急性毒性的QSAR研究

用Hartree-Fock(HF)和DFT-B3LYP方法,分别在较高基组6-31G**和6.311G**水平下,全优化计算了21种取代酚化合物.从中获得分予最高占用和最低空轨道能(EHOMO和ELUMO)、前线轨道能级差(△E＝EHOMO-ELUMO)、分子总能量(ET)、氧原了所带的最高正电荷(QH+)、最负原子的静电荷(Q-)、分子偶极矩(μ)和分子体积(V)等描述符.结合文献中标题化合物对日本长腿蛙蝌蚪的毒性值(-logLC50)和辛醇/水分配系数(logKow),由线性同归方法成功建立包含10gKow、ELUMO和Q-的三参数QSAR模型.其中,模型(5)的复相关系数R2=0.944 8,交叉验证系数Q2=0.920 5,标准偏差SE=0.187,Fisher检验值F=98.390,故其预测能力较好.由此推断,标题物对日本长腿蛙蝌蚪的毒性作用分为2步,首先穿过细胞壁在细胞内富集,以logKow和Q-描述;其次与亲核试剂发生亲电反应,以风ELUMO表示.     

Multiple Condensation filters for road detection and tracking

In this paper, we present a novel and robust road tracking system for vision-based personal navigation. Novelty of the work includes the use of multiple Condensation filters to track the road of arbitrary shape and automatic switching between trackers according to road conditions. The approach allows the road to be represented as a simple hyperbola. It also supports the representation of the road as a sequence of connected arcs/segments so that information from a digital map can be integrated into tracking. The parameters of the hyperbola road model are estimated using multiple vanishing points located in image strips. The road tracking method is robust in dealing with complex road shapes, background clutters, shadows, and road markings. Experiments using real videos demonstrate the robustness of our approach.     

“Scenario”在产品设计教学中的运用

作为决策过程中一个重要的阶段性方法,在产品设计的教学中引入"scenario"方法是非常有意义的,它以自己独特的图象表达方法,生动有趣地引导学生积极主动地思考解决问题的办法,使学生不再像以前仅凭文字描述来凭空想像,而是以更加具象的图形故事作为彼此交流的媒介。     

工业设计之创新思维方法浅析

工业设计是科学和艺术的综合体,创新思维在工业设计中具有十分重要的作用。它不仅决定了产品的外观,甚至还影响着产品的制造和使用过程。我国著名教育家陶行知先生认为,"处处是创造之地""天天是创造之时""人人是创造之人"。中国是制造大国,却不是设计大国。中国设计的原创性产品很少,中国的创新能力也亟待加强。但是随着科技的进步,中国的设计能力也在突飞猛进地发展。可以相信,未来的中国一定会成为一个设计大国。     

Positive periodic solutions of neutral predator–prey model with Beddington–DeAngelis functional response

By using a continuation theorem based on coincidence degree theory, some new sufficient conditions are obtained for the existence of positive periodic solutions for a neutral predator–prey model with the Beddington–DeAngelis functional response.     

A robust motion estimation with center-biased diamond search and its parallel architecture for motion-compensated de-interlace

For motion compensated de-interlace, the accuracy and reliability of the motion vectors have a significant impact on the performance of the motion compensated interpolation. In order to improve the robustness of motion vector, a novel motion estimation algorithm with center-biased diamond search and its parallel VLSI architecture are proposed in this paper. Experiments show that it works better than conventional motion estimation algorithms in terms of motion compensation error and robustness, and its architecture overcomes the irregular data flow and achieves high efficiency. It also efficiently reuses data and reduces the control overhead. So, it is highly suitable for HDTV applications.     

Image compression-encryption scheme combining 2D compressive sensing with discrete fractional random transform

Multimedia Tools and Applications - Most of the existing image encryption algorithms based on compressive sensing are too complex to operate. An image compression-encryption scheme with simple...     

项目教学在高职《音视频编辑与制作》课程中的探索与实践

以《音视频编辑与制作》课程为例,按照“以培养学生职业能力为核心,以实际工作过程为导向,以多媒体作品的制作流程为主线”的总体设计要求,构建和设计项目课程的教学内容,并对该课程在项目教学改革做了深入的探索与实践.     

空间教学中学生职业核心能力的培养——以“单片机技术应用”课程为例

空间教学是当前高职院校流行的辅助教学活动。以"单片机技术应用"课程为例探讨在空间教学实施过程中如何培养学生的学习兴趣,提高教学水平和效果,培养学生的职业核心能力。