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971.
以温和地区气候特征为基础,以人的热舒适度指标为目的,运用建筑气候学原理,从自然生态理念和智慧出发,分析论述了人——气候——建筑的“天人合一”关系,提出了温和地区建筑节能被动式设计的技术路线和设计措施. 相似文献
972.
Caricature is an interesting art to express exaggerated views of different persons and things through drawing. The face caricature is popular and widely used for different applications. To do this, we have to properly extract unique/specialized features of a person's face. A person's facial feature not only depends on his/her natural appearance, but also the associated expression style. Therefore, we would like to extract the neutural facial features and personal expression style for different applicaions. In this paper, we represent the 3D neutral face models in BU–3DFE database by sparse signal decomposition in the training phase. With this decomposition, the sparse training data can be used for robust linear subspace modeling of public faces. For an input 3D face model, we fit the model and decompose the 3D model geometry into a neutral face and the expression deformation separately. The neutral geomertry can be further decomposed into public face and individualized facial feature. We exaggerate the facial features and the expressions by estimating the probability on the corresponding manifold. The public face, the exaggerated facial features and the exaggerated expression are combined to synthesize a 3D caricature for a 3D face model. The proposed algorithm is automatic and can effectively extract the individualized facial features from an input 3D face model to create 3D face caricature. 相似文献
973.
Tze Leung Lai 《Sequential Analysis》2013,32(4):237-251
In the theory of asymptotically risk-efficient sequential estimation, one encounters uniform integrability of both positive and negative powers of stopping rules and moment convergence of randomly stopped statistics. We describe a simple approach to obtain these uniform integrability and moment convergence results, not only in the classical setting of i.i.d. observations but also for much more general stochastic sequences. We also use this approach to establish asymptotic risk efficiency of sequential estimators of means of stochastic sequences and to derive asymptotic approximations for the mean squared errors of ratio estimators. 相似文献
974.
Chane-Yu Lai Yu-Mei Kuo Jing-Shiang Hwang Tung-Sheng Shih 《Aerosol science and technology》2013,47(8):607-614
Certain measurement techniques (such as the asbestos method using phase contrast microscopy) require uniform deposits of the sample on a filter. The asbestos fiber analytical methods require such uniform deposition because the analysis only observes small, randomly chosen locations on the filter. In this study, a vibrating orifice monodisperse aerosol generator was used to generate methylene blue particles. The aerosols were dried by filtered compressed air and then neutralized by inducing a charge on the droplet stream that emerged from the vibrating orifice. An Aerodynamic Particle Sizer was used to measure the number concentration and size distribution of the generated aerosol particles. Meanwhile, the filter deposits were examined via image processing, combined with statistical methods for defining uniformity. In order to better define uniformity and make the indicator more universal, the uniformity was defined as the exponential of the negative CV (coefficient of variation) value which was a transformation for easily understanding the uniformity of the filter deposits. The experimental results demonstrated that, when aerosol counting was performed, the equal area approach was superior to the equivalent distance approach. 相似文献
975.
The chemical capture of CO2 by either aqueous Na2CO3 and K2CO3 or nonaqueous solutions of the amines 2‐amino‐2‐methyl‐1‐propanol (AMP) or piperazine (PZ) is described. The captured CO2 is stored as solid NaHCO3, KHCO3, and AMP or PZ carbamates. Solid NaHCO3 and KHCO3 are decomposed at 200 °C and 250 °C, respectively, to regenerate the carbonates for their reuse. In the experiments with AMP or PZ, the solid carbamates are decomposed at 80 °C–110 °C to regenerate the free amines. The absence of water in the desorption‐regeneration step is intriguing and could have the potential of reducing one of the major disadvantages of aqueous absorbents, namely the energy cost of the regeneration step and amine degradation, yet preserving the efficiency of the absorption in the liquid phase. 相似文献
976.
水泥生产工艺与混凝土耐久性的关系 总被引:4,自引:2,他引:2
1 影响混凝土耐久性的因素 水泥是混凝土的一种重要原料,它的性能对混凝土性能有十分重要的影响.混凝土诸多性能中耐久性非常重要,如果混凝土结构物没有达到预期使用年限而过早地被破坏,不但经济损失巨大而且危及人们的安全.黄士元等[1]将混凝土破坏的原因分为四大类:①磨损;②物理因素的破坏;③化学作用的破坏;④钢筋锈蚀造成的破坏. 相似文献
977.
Shao-Ching Liao Chia-Sheng Lai Di-Di Yeh M. Habibur Rahman Chain-Shu Hsu Hsin-Lung Chen Show-An Chen 《Reactive and Functional Polymers》2009,69(7):498-506
The structures of an amphiphilic conjugated graft copolymer, poly(2,3-diphenyl-5-(trimethylene-heptadeca(oxyethylene)-methoxy-phenylene vinylene) (denoted as PVEO17) composing of a conjugated DP-PPV backbone and PEO side chains, in bulk and solutions with tetrahydrofuran (THF) and water have been investigated by small-angle X-ray scattering (SAXS). In bulk state, the DP-PPV main chains in PVEO17 stacked to form flat disk microdomains dispersed in the PEO side-chain matrix. The corresponding wide angle X-ray scattering pattern revealed the existence of crystallinity of the PEO side chains. The structure of the polymer in solution was affected by the solvent quality and the polymer concentration. PVEO17 chains were relatively well dispersed in THF. In aqueous solutions, however, the amphiphilic PVEO17 chains aggregated significantly over the concentration range of 1–8 wt%, where the polymer was found to self-organize to form cylindrical micelles with the aggregation number increasing with the increase of concentration. The photophysical properties characterized by UV–Vis and photoluminescence spectroscopy were strongly affected by the aggregation state of the polymer. 相似文献
978.
编者按:Communications of ACM 2000年第9期有一个关于"会话式界面"的专栏,集中发表了7篇文章,代表了这个方向的研究和应用现状.长期以来,人们总是在不断探索更加适合于人使用的计算机界面.有人预计,会话式界面会成为下一个"浪潮".现将该专栏的客座编辑Jennifer Lai的引言译出,引言中简略介绍了该专栏7篇文章的内容. 相似文献
979.
Lai M.-I. Wu T.-Y. Hsieh J.-C. Wang C.-H. Jeng S.-K. 《Microwaves, Antennas & Propagation, IET》2009,3(1):47-54
A basic antenna structure to design pattern and pattern/frequency reconfigurable antennas is proposed. The structure consists of an L-shaped slot, PIN diodes, lumped capacitors and bias networks. The PIN diodes and the lumped capacitors located at specific positions are used to create short circuits across the slot. By carefully controlling these diodes, the induced current distribution around the slot can be changed, resulting in different antenna radiation patterns. Thus, a pattern reconfigurable antenna can be achieved. The proposed structure is then extended to design frequency/pattern reconfigurable antennas by introducing varactor diodes. Two compact reconfigurable antennas based on the proposed structure are designed and implemented to prove the design concepts. The experiment results fully demonstrated the performances of the proposed designs. Owing to the compact size and ease on manufacture, the proposed structure can be a promising solution in compact wireless devices such as smart phones and notebook computers. 相似文献
980.
SH Wong Y Xu T Zhang G Griffiths SL Lowe VN Subramaniam KT Seow W Hong 《Canadian Metallurgical Quarterly》1999,10(1):119-134
Syntaxin 1, synaptobrevins or vesicle-associated membrane proteins, and the synaptosome-associated protein of 25 kDa (SNAP-25) are key molecules involved in the docking and fusion of synaptic vesicles with the presynaptic membrane. We report here the molecular, cell biological, and biochemical characterization of a 32-kDa protein homologous to both SNAP-25 (20% amino acid sequence identity) and the recently identified SNAP-23 (19% amino acid sequence identity). Northern blot analysis shows that the mRNA for this protein is widely expressed. Polyclonal antibodies against this protein detect a 32-kDa protein present in both cytosol and membrane fractions. The membrane-bound form of this protein is revealed to be primarily localized to the Golgi apparatus by indirect immunofluorescence microscopy, a finding that is further established by electron microscopy immunogold labeling showing that this protein is present in tubular-vesicular structures of the Golgi apparatus. Biochemical characterizations establish that this protein behaves like a SNAP receptor and is thus named Golgi SNARE of 32 kDa (GS32). GS32 in the Golgi extract is preferentially retained by the immobilized GST-syntaxin 6 fusion protein. The coimmunoprecipitation of syntaxin 6 but not syntaxin 5 or GS28 from the Golgi extract by antibodies against GS32 further sustains the preferential interaction of GS32 with Golgi syntaxin 6. 相似文献