649 resultados para iOS
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本论文对沿阶草族Ophiopogoneae(Endl.)Kunth的研究历史作了回顾,从染色体、形态学和解剖学角度对此族作了研究,并作了数值分类和分支 系统学分析的尝试,在此基础上探讨了这个族的系统学问题. 1)本论文对此族三属37种123居群的染色体数目、基数及核型不对称性作了研究,其中19种的染色体为首次报道.它们是:P.macrostegiaHance, P.yunnanensis Wang et Tang,P.ophiopogonoides Wang et Tang,O. sarmentosus Wang et Dai,O.tienensis Wang et Tang, O.sylvicola Wang et Tang, O.fooningensis Wang et Dai, O.mairei L6vl.,O.szechuanensis Wang et Tang, O.angustiatus (Wang et Tang) S.C.Chen, O.amblyphyllus Wang et Dai,O.clavatus Wright ex Oliver,O.clivioidesD.M.Zhang et Hong, O.longiscaposus D.M.Zhang et Hong,O.umbraticola Hance,O.fuiD.M.Zhang ntHong,O.zingiberaceus Wang et Dai,O.gangxiensisd.M.Zhang et Hong,O. lo fouense L6vl. 2)在此族中首次报道了2n = 2x = 34的异基数二倍体,同时在O.umbraticola,O.japonicus,O.cLarkei中报道了2n=68的异基数二倍体,过核型和减数分裂等证明异基数是在二倍体水平上形成,并发展成倍性系列的. 3)在此族中首次报道了B染色体的存在,已确证了两种(P.macrostegia和D.tienensis).一种尚需进一步确证(O.Larkei). 4)通过对随体位置的系统研究,发现在此族中随体位置具有分类价值. 5)通过对8个种内多倍体、4个多倍体种的研究,表明多倍体分布于较北、海拔较高的地方,而亚洲热带地区的种,则无多倍体,同时在具异基数种类和核型较不对称种类上亦有这种分布特征;在确定了分布的多度中心的基础上,提出喜马拉雅_横断山脉到川西、川南一带是沿阶草属和山麦冬属的近代分化中心. 6)通过染色体结构和数目几个角度的研究,表明球子草属与其他两属在。染色体水平上已发生很大分化,但其属内的分化则不表现在染色体上.其他二属内部则有基数、倍性和核型不对称方面的分化.综观此族,染色体具有由核 型对称向不对称、由二倍体向多倍体、由种内多倍体向多倍体种,由单一基数向种内异基数几个方向进化的趋势. 7)通过对此族的形态观察和分析,提出茎或根状茎分枝方式是属下分类的重要依据;认为本族植物的花序是由圆锥花序简化而来,但残留着圆锥花序特征;并提出了本族花、茎、叶、根几个方面的形态演化趋势. 8)通过对此族二属21种的子房解剖,发现三属均有半下位子房,因而认为子房半下位作为分属检索性状是不合适的.此外还观察到子房着生位置在种内亦有变异,对这种变异的意义进行了探讨. 9)通过此族三属46种2变种的数值分类处理,表明本族由球子草群和沿阶草一山麦冬群两大类群组成,山麦冬属仅是与沿阶草属一个组(葶花组)并列的分类单元,其内部分化较小,而沿阶草属则较大. 10)通过46个性状计算了山麦冬属和沿阶草属共6个广布的“群内总体相 似度”(IOS),表明山麦冬属3个种种内个体之间、种间个体之间的分化很小,且可能有杂交现象,结合染色体资料和分布特征,认为这个属的发生是个相当晚近的事件. 11)本文从形态和染色体角度,认为沿阶草族是一个自然类群;由分支系 统学分析表明,此族由二个单系类群(球子草属和沿阶草属)组成,沿阶草属含两个单系的组,其中各含3个系,山麦冬属为其中一个系.这一结果与数值 分类结果和染色体资料相符. 12)为避免单一分类方法可能导致的不合理结果,本文以自拟的一种综合分类方法,把谱系、进化、分化诸因素均予考虑,得出一个三维图象,以图象 上相对等径的球作为分类依据,得出的结果与分支系统学和数值分类结果基本一致.因此,山麦冬属作为与沿阶草属等阶的分类地位,应予重新考虑. 13)本文最后对这个族的全面修订提出几点建议. 14)此外,本文还描述了沿阶草属4个新种.
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The Internet of Things (IOT) concept and enabling technologies such as RFID offer the prospect of linking the real world of physical objects with the virtual world of information technology to improve visibility and traceability information within supply chains and across the entire lifecycles of products, as well as enabling more intuitive interactions and greater automation possibilities. There is a huge potential for savings through process optimization and profit generation within the IOT, but the sharing of financial benefits across companies remains an unsolved issue. Existing approaches towards sharing of costs and benefits have failed to scale so far. The integration of payment solutions into the IOT architecture could solve this problem. We have reviewed different possible levels of integration. Multiple payment solutions have been researched. Finally we have developed a model that meets the requirements of the IOT in relation to openness and scalability. It supports both hardware-centric and software-centric approaches to integration of payment solutions with the IOT. Different requirements concerning payment solutions within the IOT have been defined and considered in the proposed model. Possible solution providers include telcos, e-payment service providers and new players such as banks and standardization bodies. The proposed model of integrating the Internet of Things with payment solutions will lower the barrier to invoicing for the more granular visibility information generated using the IOT. Thus, it has the potential to enable recovery of the necessary investments in IOT infrastructure and accelerate adoption of the IOT, especially for projects that are only viable when multiple benefits throughout the supply chain need to be accumulated in order to achieve a Return on Investment (ROI). In a long-term perspective, it may enable IT-departments to become profit centres instead of cost centres. © 2010 - IOS Press and the authors. All rights reserved.
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The paper presents hydraulic conductivity, unconfined compression strength (UCS) and triaxial test results of an 11 year old slag-cement-bentonite (CB) cut-off wall material and identifies factors affecting their long-term performance. The laboratory tests were performed on three types of CB samples ranging from contaminated block field samples to uncontaminated laboratory cast samples. The results showed that hydraulic conductivity reduces till 3 years and UCS increases till 90 days, but there after it remains constant till 11 years of age. The mean hydraulic conductivity and UCS values of block field samples are inferior and have large variability than laboratory cured samples. Such variations are mainly because of heterogeneity caused by aggressive environment and impurities within the specimen. Consolidated undrained triaxial test found that under an effective confining pressure of less than 200 kPa, tension failure occurred since the minor principal stress dropped to zero value at failure. The research outcome is useful for understanding future liability of CB wall and improving their design. © 2009 IOS Press.
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An innovative technique based on optical fibre sensing that allows continuous strain measurement has recently been introduced in structural health monitoring. Known as Brillouin Optical Time-Domain Reflectometry (BOTDR), this distributed optical fibre sensing technique allows measurement of strain along the full length (up to 10km) of a suitably installed optical fibre. Examples of recent implementations of BOTDR fibre optic sensing in piles are described in this paper. Two examples of distributed optical fibre sensing in piles are demonstrated using different installation techniques. In a load bearing pile, optical cables were attached along the reinforcing bars by equally spaced spot gluing to measure the axial response of pile to ground excavation induced heave and construction loading. Measurement of flexural behaviour of piles is demonstrated in the instrumentation of a secant piled wall where optical fibres were embedded in the concrete by simple endpoint clamping. Both methods have been verified via laboratory works. © 2009 IOS Press.
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The increments of internal forces induced in a tunnel lining during earthquakes can be assessed with several procedures at different levels of complexity. However, the substantial lack of well-documented case histories still represents a difficulty in order to validate any of the methods proposed in literature. To bridge this gap, centrifuge model tests were carried out on a circular aluminium tunnel located at two different depths in dense and loose dry sand. Each model has been instrumented for measuring soil motion and internal loads in the lining and tested under several dynamic input signals. The tests performed represented an experimental benchmark to calibrate dynamic analyses with different approaches to account for soil-tunnel kinematic interaction. © 2009 IOS Press.
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Users’ initial perceptions of their competence are key motivational factors for further use. However, initial tasks on a mobile operating system (OS) require setup procedures, which are currently largely inconsistent, do not provide users with clear, visible and immediate feedback on their actions, and require significant adjustment time for first-time users. This paper reports on a study with ten users, carried out to better understand how both prior experience and initial interaction with two touchscreen mobile interfaces (Apple iOS and Google Android) affected setup task performance and motivation. The results show that the reactions to setup on mobile interfaces appear to be partially dependent on which device was experienced first. Initial experience with lower-complexity devices improves performance on higher-complexity devices, but not vice versa. Based on these results, the paper proposes six guidelines for designers to design more intuitive and motivating user interfaces (UI) for setup procedures. The preliminary results indicate that these guidelines can contribute to the design of more inclusive mobile platforms and further work to validate these findings is proposed.
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Human listeners can identify vowels regardless of speaker size, although the sound waves for an adult and a child speaking the ’same’ vowel would differ enormously. The differences are mainly due to the differences in vocal tract length (VTL) and glottal pulse rate (GPR) which are both related to body size. Automatic speech recognition machines are notoriously bad at understanding children if they have been trained on the speech of an adult. In this paper, we propose that the auditory system adapts its analysis of speech sounds, dynamically and automatically to the GPR and VTL of the speaker on a syllable-to-syllable basis. We illustrate how this rapid adaptation might be performed with the aid of a computational version of the auditory image model, and we propose that an auditory preprocessor of this form would improve the robustness of speech recognisers.
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Ferr?, S. and King, R. D. (2004) A dichotomic search algorithm for mining and learning in domain-specific logics. Fundamenta Informaticae. IOS Press. To appear
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This thesis presents several routes towards achieving artificial opal templates by colloidal self-assembly of polystyrene (PS) or poly(methyl methacrylate) (PMMA) spheres and the use of these template for the fabrication of V2O5 inverse opals as cathode materials for lithium ion battery applications. First, through the manipulation of different experimental factors, several methods of affecting or directing opal growth towards realizing different structures, improving order and/or achieving faster formation on a variety of substrates are presented. The addition of the surfactant sodium dodecyl sulphate (SDS) at a concentration above the critical micelle concentration for SDS to a 5 wt% solution of PMMA spheres before dip-coating is presented as a method of achieving ordered 2D PhC monolayers on hydrophobic Au-coated silicon substrates at fast and slow rates of withdrawal. The effect that the degree of hydrophilicity of glass substrates has on the ordering of PMMA spheres is next investigated for a slow rate of withdrawal under noise agitation. Heating of the colloidal solution is also presented as a means of affecting order and thickness of opal deposits formed using fast rate dip coating. E-beam patterned substrates are shown as a means of altering the thermodynamically favoured FCC ordering of polystyrene spheres (PS) when dip coated at slow rate. Facile routes toward the synthesis of ordered V2O5 inverse opals are presented with direct infiltration of polymer sphere templates using liquid precursor. The use of different opal templates, both 2D and 3D partially ordered templates, is compared and the composition and arrangement of the subsequent IO structures post infiltration and calcination for various procedures is characterised. V2O5 IOs are also synthesised by electrodeposition from an aqueous VOSO4 solution at constant voltage. Electrochemical characterisation of these structures as cathode material for Li-ion batteries is assessed in a half cell arrangement for samples deposited on stainless steel foil substrates. Improved rate capabilities are demonstrated for these materials over bulk V2O5, with the improvement attributed to the shorter Li ion diffusion distances and increased electrolyte infiltration provided by the IO structure.
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Three-dimensional vanadium pentoxide (V2O5) material architectures in the form of inverse opals (IOs) were fabricated using a simple electrodeposition process into artificial opal templates on stainless steel foil using an aqueous solution of VOSO4.χH2O with added ethanol. The direct deposition of V2O5 IOs was compared with V2O5 planar electrodeposition and confirms a similar progressive nucleation and growth mechanism. An in-depth examination of the chemical and morphological nature of the IO material was performed using X-ray crystallography, X-ray photoelectron spectroscopy, Raman scattering and scanning/transmission electron microscopy. Electrodeposition is demonstrated to be a function of the interstitial void fraction of the artificial opal and ionic diffusivity that leads to high quality, phase pure V2O5 inverse opals is not adversely affected by diffusion pathway tortuosity. Methods to alleviate electrodeposited overlayer formation on the artificial opal templates for the fabrication of the porous 3D structures are also demonstrated. Such a 3D material is ideally suited as a cathode for lithium ion batteries, electrochromic devices, sensors and for applications requiring high surface area electrochemically active metal oxides.
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In recent years international policies have aimed to stimulate the use of information and communication technologies (ICT) in the field of health care. Belgium has also been affected by these developments and, for example, health electronic regional networks ("HNs") are established. Thanks to a qualitative case study we have explored the implementation of such innovations (HN) to better understand how health professionals collaborate through the HN and how the HN affect their relationships. Within the HNs studied a common good unites the actors: the continuity of care for a better quality of care. However behind this objective of continuity of care other individual motivations emerge. Some controversies need also to be resolved in order to achieve cooperative relationships. HNs have notably to take national developments into account. These developments raise the question of the control of medical knowledge and medical practice. Professional issues, and not only practical changes, are involved in these innovations. © 2008 The authors and IOS Press. All rights reserved.
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p.229-237