Making sky lanterns from polygonal meshes

Releasing sky lanterns is a popular way of celebrating festivals and ceremonies in the Asian countries. This paper presents a computer-aided approach to help novice users to design flyable sky lantern with desired shape. Given a closed up-right 3D model with a user-specified cutting on the bottom, our system optimizes the shape by regularizing the boundary, smoothing the geometry and improving the volume-to-area ratio to make it feasible for flying. The optimized shape is then approximated by a set of developable patches. Next, through a physical analysis step that tests the flying condition and determines the optimal size, the approximated shape is flattened into 2D patches, which can be printed out and glued together to form the airbag. Finally, the user can attach the airbag to a bamboo frame and assemble the fuel cell. We successfully apply our prototype system to design and construct real sky lanterns.     

降膜波动特性的研究

本文提出了一种测定膜厚的新方法－双电导探针法，测定了高湍流降膜的厚度沿降膜管管程的变化情况，探讨了径向平均膜厚及膜厚的概率密度分布沿管程的变化规律，证明降膜的波动特性同时受到液相雷诺数和管程的影响。并对平均膜厚和液相雷诺数作了经验关联，得出NT＝（δ^ )^2/3 [8.92(ReL/4)^5/2 6.0×10^-6(ReL/4)^9/2]^2/15。     

Effect of reactive diluents on properties of unsaturated polyester/montmorillonite nanocomposites

Unsaturated polyester (UP)/montmorillonite (MMT) nanocomposite was prepared by using hydroxypropylacrylate (HPA) as a reactive diluent instead of conventional styrene monomer and the effect of polarity of reactive diluent on properties of nanocomposite was investigated. X‐ray and mechanical test data indicated that mixing for an extended period of time is essential to enhance the physical properties of nanocomposites in the UP/Cloisite 6A system. This was attributed to the high polarity of HPA that may disturb the preintercalation of UP resin into the galleries of MMT. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 238–242, 2004     

微波介质陶瓷及其展望

综述了微波介质陶瓷材料的特性和发展现状，介绍了几种重要的微波介质陶瓷体系，讨论了微波介质陶瓷性能的影响因素，指出了改善其性能的途径和微波介质陶瓷的预期进展。     

新型离子液体气相色谱固定相研究

合成了一种用作新型气相色谱固定相的室温离子液体[C7H17NO] [(CF3SO2)2N]-,并考察其色谱性能。该固定相具有较好的成膜性、较高的柱效、较强的极性,对正构烷烃、芳香族化合物以及一些位置异构体具有良好的分离效果。     

Structure Aware Visual Cryptography

Visual cryptography is an encryption technique that hides a secret image by distributing it between some shared images made up of seemingly random black‐and‐white pixels. Extended visual cryptography (EVC) goes further in that the shared images instead represent meaningful binary pictures. The original approach to EVC suffered from low contrast, so later papers considered how to improve the visual quality of the results by enhancing contrast of the shared images. This work further improves the appearance of the shared images by preserving edge structures within them using a framework of dithering followed by a detail recovery operation. We are also careful to suppress noise in smooth areas.     

水稻全生育期应用腐植酸液肥的效果初报

腐植酸液肥——科力素(KLS)对水稻生长发育影响较大。试验表明,水稻苗床施用KLS明显刺激秧苗生长,处理区根长、根数、地上地下百株鲜重及带蘖率都好于对照区。不同生育时期喷施KLS,水稻发育加快,自返青期开始到成熟期都有不同程度提前,一般早熟3～5d。产量增加幅度为4.7%～21.1%,平均增产11.3%,亩增效37.44～204.48元,平均为99.2元,产投比约为12∶1。     

方坯连铸高效化二冷技术

建立了方坯高效连铸二冷数学模型,提出了喷嘴有效喷淋系数和二冷有效比水量的概念.依据二冷均匀冷却的思想,重新设计并优化了二冷喷淋结构和喷嘴的布置,增加了一个二冷喷淋段.提出了新的二冷水模型,即Qi=a bv cv2=d(△T-30) F;二冷各段的喷水量与拉速、浇铸温度、钢水成分和二冷水温相关.实践证明,经优化后的二冷结构和二冷水模型合理,拉速大幅度提高,150×150 mm2断面的最高拉速达3.8～4.0 m/min;铸坯质量明显改善,产量显著提高,经济效益显著.     

谈陶瓷材料对草坪灯的介入

陶瓷与自然有着天然的联系,能带给人们回归自然的审美情趣。陶瓷材料制作的灯具以其自然多变的机理、色调和形 状,比其他材料的灯具更易与景现环境融为一体。本文通过对草坪灯现状的分析,根据陶瓷材料的特点,提出陶瓷介入 草坪灯,对丰富室外环境审美客体有着积极的意义。     

热溶过滤法脱除煤焦油沥青中喹啉不溶物的研究

以5种煤焦油沥青为原料,喹啉为溶剂,研究了热溶过滤法脱除喹啉不溶物(QI)等杂质的效应,目的是制备QI含量较低的净化沥青。结果表明:热溶过滤法可以有效地脱除喹啉不溶物,QI脱除率随滤网网目增加而提高,但阻力增加,脱除时间变长。综合考虑脱除率和实际可操作性,采用1000目的滤布,QI含量可以降到0.3%以下,基本能达到要求。采用凝胶色谱对QI脱除后沥青的组成和分子量分布的研究表明,热溶过滤脱除了沥青中的大分子组分,分子量减小,分子量分布变窄。