The Mona Lisa identification: Evidence from a computer analysis

A recent computer-aided study identified the model immortalized in Leonardo da Vinci's celebratedMona Lisa to be none other than the artist himself. A follow-up investigation empolying similar techniques identifies the subject of asecond HiddenMona Lisa by the same artist. Analysis of photographic and x-ray images indicates that Leonardo first created a sketch of Isabella, Duchess of Aragon, which he later painted over with theMona Lisa, using himself as the model.     

丙烯酸酯类无皂LIPN阻尼材料的合成和动态力学性能

采用无皂乳液分步聚合法合成了一系列LIPN阻尼材料，利用动态粘弹谱研究了其动态力学性能。结果表明：网络组分的相容性对阻尼性能的影响显，第三个网络的引入，显地改善了网络组分间的相容性，得到了阻尼性能优良的材料；交联剂用量在一定范围内变化有助于提高涂膜的阻尼性能；通过引入含羧基的共聚组分，提高了材料的高温阻尼性能。     

日语「~(だ)からね」句式研究

本文从日语教育的角度对日汉对译时「~(だ)からね」的句法意义进行分析。表明原因理由的「(だ)からね」有时被译为连词"因为",但从实例来看更多情况并不译成"因为"。反过来,汉语句中在表示判断主张原因和理由,虽然没有使用连词"因为"等特定的形式,但在译成日语时常常使用「(だ)からね」这一形式。汉语不用标志性的"因为"之类的连词也能表明上下文的逻辑关系,而日语在表达事物间的逻辑关系时却要用「(だ)からね」之类的形式加以明示。     

土坝在设计和运行中防治白蚁危害的研究

以往在水库大坝发生白蚁危害病情后,方采取工程措施进行除险加固。为把白蚁控制在危害之前,本文结合工程典型实例,根据气候、土壤、植被等建坝外部环境条件和白蚁生存需具备的土、水、食料基本因素,考虑白蚁具有喜温好湿、畏光避风、蔓延等生物特性,通过填筑坝料土质分析,研究了水库蓄水坝体浸润性、坝土级配及湿度与白蚁生存之间的关系,并提出相应对策以达到防患于未然。结果表明,坝体结构设计时,通过截断白蚁吸水水源,增加坝体干燥区,缩限白蚁生存空间;通过调整坝料级配,防止白蚁筑巢;合理采用护坡,切断白蚁食源。同时,结合水库运行管理,采取"预防为主,综合防治"的措施,使坝体周边一定范围内成为无蚁区,防止白蚁蔓延至坝,维护水库大坝的安全。     

基于Elastos操作系统的图形引擎的设计与实现

Elastos图形系统Vinci是Elastos操作系统的一个子系统,负责在屏幕上绘制像素、文本和用户界面（包括窗口、菜单、对话框）等。图形引擎的体系结构决定了此系统的简易性、灵活性、效率和稳定性,所以它的设计又显得至关重要。分别介绍了基于Elastso操作系统的图形系统Vinci、此图形引擎的设计需求,在此基础上根据图形系统的引擎功能设计需求结合nitros图形系统Vinci自有的特点,实现了Vinci引擎的设计,使得基于Vinci系统的Elastos操作系统可以完成各种各样的操作。     

A comparative runtime analysis of heuristic algorithms for satisfiability problems

The satisfiability problem is a basic core NP-complete problem. In recent years, a lot of heuristic algorithms have been developed to solve this problem, and many experiments have evaluated and compared the performance of different heuristic algorithms. However, rigorous theoretical analysis and comparison are rare. This paper analyzes and compares the expected runtime of three basic heuristic algorithms: RandomWalk, (1+1) EA, and hybrid algorithm. The runtime analysis of these heuristic algorithms on two 2-SAT instances shows that the expected runtime of these heuristic algorithms can be exponential time or polynomial time. Furthermore, these heuristic algorithms have their own advantages and disadvantages in solving different SAT instances. It also demonstrates that the expected runtime upper bound of RandomWalk on arbitrary k-SAT (k?3) is O(n(k−1)), and presents a k-SAT instance that has Θ(n(k−1)) expected runtime bound.     

Quadratic optimal neural fuzzy control for synchronization of uncertain chaotic systems

This paper presents a novel quadratic optimal neural fuzzy control for synchronization of uncertain chaotic systems via H^∞ approach. In the proposed algorithm, a self-constructing neural fuzzy network (SCNFN) is developed with both structure and parameter learning phases, so that the number of fuzzy rules and network parameters can be adaptively determined. Based on the SCNFN, an uncertainty observer is first introduced to watch compound system uncertainties. Subsequently, an optimal NFN-based controller is designed to overcome the effects of unstructured uncertainty and approximation error by integrating the NFN identifier, linear optimal control and H^∞ approach as a whole. The adaptive tuning laws of network parameters are derived in the sense of quadratic stability technique and Lyapunov synthesis approach to ensure the network convergence and H^∞ synchronization performance. The merits of the proposed control scheme are not only that the conservative estimation of NFN approximation error bound is avoided but also that a suitable-sized neural structure is found to sufficiently approximate the system uncertainties. Simulation results are provided to verify the effectiveness and robustness of the proposed control method.     

Rectangle packing with additional restrictions

We formulate a generalization of the NP-complete rectangle packing problem by parameterizing it in terms of packing density, the ratio of rectangle areas, and the aspect ratio of individual rectangles. Then we show that almost all restrictions of this problem remain NP-complete and identify some cases where the answer to the decision problem can be found in constant time.     

普通钠钙玻璃SCC特性的测试与分析

本文探索出一种玻璃材料SCC特性的有效测试方法,并对普通钠钙玻璃在水,甲醇和甲酰胺三种介质申的SCC特性进行了测试与分析。结果表明,其da/dt-K_I曲线均无平台阶段,这是因为三种介质均是普通钠钙玻璃的活性促进剂。三种介质的SCC敏感性依次为水>甲醇>甲酰胺。进一步讨论认为,SCC敏感性与介质的未共享电子轨道的非对称性及给质子键的活性成正相关关系。