948 resultados para Sarpi, Paolo, 1552-1626
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云南蒙自石榴干腐病助故阮以菌丝体和分生抢子在僵果、干 腐果及其他感病部位越冬。翌年经风雨、昆虫和人为活动在果园广为传播。石榴 花、幼果、果实期均可感病发病, 等筒花丝最易感病。果实发病率达一, 重者达一。采取综合治理措施, 其中重要的是在首次连续降雨前利去干 花丝、套袋和树冠多次喷清水, 提前水解、淡化干花丝、伤口渗出液的微酸性度, 可 控制该病的发生危害, 危害率由原来的一现降为一。
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Details are given of the results of research conducted at the SEAFDEC Aquaculture Department on abalone (Haliotis asinina). The following areas are covered: reproductive biology; induced spawning; raising abalone in the hatchery; and, cage culture trials.
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在pH 3.0时,去除85和95~105 USP u/mg粗品肝素钠的杂蛋白分别使用 0.05%和0.03%的YNB 99一l。120 USP u/mg以上的粗品在pH中性下直接使用0.05% 的YNB 99—1即可。在氧化精制中,加入0.005%的YNB 99—1可使HzOz用量减少至 1.5%,氧化时间缩短至12 h。精品效价170 USP u/mg以上,产品收率90%以上。
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Most previous work on trainable language generation has focused on two paradigms: (a) using a statistical model to rank a set of generated utterances, or (b) using statistics to inform the generation decision process. Both approaches rely on the existence of a handcrafted generator, which limits their scalability to new domains. This paper presents BAGEL, a statistical language generator which uses dynamic Bayesian networks to learn from semantically-aligned data produced by 42 untrained annotators. A human evaluation shows that BAGEL can generate natural and informative utterances from unseen inputs in the information presentation domain. Additionally, generation performance on sparse datasets is improved significantly by using certainty-based active learning, yielding ratings close to the human gold standard with a fraction of the data. © 2010 Association for Computational Linguistics.
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The tensile response of single crystal films passivated on two sides is analysed using climb enabled discrete dislocation plasticity. Plastic deformation is modelled through the motion of edge dislocations in an elastic solid with a lattice resistance to dislocation motion, dislocation nucleation, dislocation interaction with obstacles and dislocation annihilation incorporated through a set of constitutive rules. The dislocation motion in the films is by glide-only or by climb-assisted glide whereas in the surface passivation layers dislocation motion occurs by glide-only and penalized by a friction stress. For realistic values of the friction stress, the size dependence of the flow strength of the oxidised films was mainly a geometrical effect resulting from the fact that the ratio of the oxide layer thickness to film thickness increases with decreasing film thickness. However, if the passivation layer was modelled as impenetrable, i.e. an infinite friction stress, the plastic hardening rate of the films increases with decreasing film thickness even for geometrically self-similar specimens. This size dependence is an intrinsic material size effect that occurs because the dislocation pile-up lengths become on the order of the film thickness. Counter-intuitively, the films have a higher flow strength when dislocation motion is driven by climb-assisted glide compared to the case when dislocation motion is glide-only. This occurs because dislocation climb breaks up the dislocation pile-ups that aid dislocations to penetrate the passivation layers. The results also show that the Bauschinger effect in passivated thin films is stronger when dislocation motion is climb-assisted compared to films wherein dislocation motion is by glide-only. © 2012 Elsevier Ltd.
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We derive a random-coding upper bound on the average probability of error of joint source-channel coding that recovers Csiszár's error exponent when used with product distributions over the channel inputs. Our proof technique for the error probability analysis employs a code construction for which source messages are assigned to subsets and codewords are generated with a distribution that depends on the subset. © 2012 IEEE.
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The interplay between robotics and neuromechanics facilitates discoveries in both fields: nature provides roboticists with design ideas, while robotics research elucidates critical features that confer performance advantages to biological systems. Here, we explore a system particularly well suited to exploit the synergies between biology and robotics: high-speed antenna-based wall following of the American cockroach (Periplaneta americana). Our approach integrates mathematical and hardware modeling with behavioral and neurophysiological experiments. Specifically, we corroborate a prediction from a previously reported wall-following template - the simplest model that captures a behavior - that a cockroach antenna-based controller requires the rate of approach to a wall in addition to distance, e.g., in the form of a proportional-derivative (PD) controller. Neurophysiological experiments reveal that important features of the wall-following controller emerge at the earliest stages of sensory processing, namely in the antennal nerve. Furthermore, we embed the template in a robotic platform outfitted with a bio-inspired antenna. Using this system, we successfully test specific PD gains (up to a scale) fitted to the cockroach behavioral data in a "real-world" setting, lending further credence to the surprisingly simple notion that a cockroach might implement a PD controller for wall following. Finally, we embed the template in a simulated lateral-leg-spring (LLS) model using the center of pressure as the control input. Importantly, the same PD gains fitted to cockroach behavior also stabilize wall following for the LLS model. © 2008 IEEE.
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目的了解武汉市饮用水中浮游藻类的污染情况。方法分别于1999-2001年春、夏、秋、冬对武汉市不同水源供水区末梢水和同一地点水箱水进行4次采样,进行藻类形态学检测。结果生活饮用水中浮游藻类有蓝藻门(Cyanophyta)、隐藻门(Cryptohyta)、金藻门(Chrysophyta)、硅藻门(Bacillariophyta)、裸藻门(Euglenophyta)、绿藻门(Chlorophyta)等6个门,56个属、97个种藻类(其中67个鉴定到种,30个鉴定到属)。城市末梢水中浮游藻类检出为89%,饮水水
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在同一实验条件下,通过8周生长实验比较研究了不同玉米淀粉含量的饲料对长吻和异育银鲫生长、饲料利用和鱼体组成的影响,以探讨肉食性和杂食性鱼类对玉米淀粉利用的差异。长吻的实验饲料是5种等氮等脂、玉米淀粉含量分别为0、5%、10%、15%和20%的半精制饲料。异育银鲫的实验饲料是5种等氮等脂、玉米淀粉含量分别为6%、12%、18%、24%和30%的半精制饲料。每天饱食投喂鱼两次。实验结果表明:对于长吻,玉米淀粉含量为5%和10%饲料组的特定生长率显著高于另外3组(Duncan s多重比较,P<0.05)。
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The paper considers the feedback stabilization of periodic orbits in a planar juggler. The juggler is "blind," i.e, he has no other sensing capabilities than the detection of impact times. The robustness analysis of the proposed control suggests that the arms acceleration at impact is a crucial design parameter even though it plays no role in the stability analysis. Analytical results and convergence proofs are provided for a simplified model of the juggler. The control law is then adapted to a more accurate model and validated in an experimental setup. © 2007 IEEE.
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The paper studies the properties of a sinusoidally vibrating wedge billiard as a model for 2-D bounce juggling. It is shown that some periodic orbits that are unstable in the elastic fixed wedge become exponentially stable in the nonelastic vibrating wedge. These orbits are linked with certain classical juggling patterns, providing an interesting benchmark for the study of the frequency-locking properties in human rhythmic tasks. Experimental results on sensorless stabilization of juggling patterns are described. © 2006 IEEE.
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Changing the ratio of light-harvesting pigments was regarded as an efficient way to improve the photosynthesis rate in microalgae, but the underlying mechanism is still unclear. In the present study, a mutant of Anabeana simensis (called SP) was selected from retrieved satellite cultures. Several parameters related with photosynthesis, such as the growth, photosynthesis rate, the content of photosynthetic pigment, low temperature fluorescence spectrum (77K) and electron transport rate, were compared with those of the wild type. It was found that the change in the ratio of light-harvesting pigments in the mutant led to more efficient light energy transfer and usage in mutant than in the wild type. This may be the reason why the mutant had higher photosynthesis and growth rates.