最大熵和条件随机场模型相融合的藏文人名识别

藏文人名识别是藏文信息处理领域研究的难点之一,其识别效果直接影响到藏文自动分词的精度和相关应用系统的性能,包括藏汉翻译、藏文信息检索、文本分类等。该文在分析藏文人名构成规律和特点的基础上,提出了一种最大熵和条件随机场相融合的藏文人名识别方法。实验表明,该方法可以获取较好的识别效果,在我们的测试集上F-测度值到达了93.08%。     

基于Android平台的风机手持操作仪开发

基于Android平台开发了一款风机手持操作仪, 用于风机的日常监视、维护及设置。以TCP/IP协议和MODBUS协议为基础, 与风机主控系统实现基础数据通讯, 并通过交互界面上的触控操作来完成监视、维护及设置功能; 同时, 利用数据库技术实现对风机和用户数据的存储与管理, 并对用户关键信息进行加密处理以提升安全性。实际应用表明了该设备的可行性、有效性, 并且具备灵活、便携、经济等特点。     

Prediction of liquid film mass transfer coefficients in packed columns using liquid holdup

A unique characteristic linear dimension (d), defined as the cube root of the specific liquid holdup (h_sp) in the packed column, was used to correlate successfully the liquid film mass transfer coefficient k_La for gas absorption-desorption for sparingly soluble gases in liquids below loading. To produce this simple, dimensionless correlation, k_La data reported in literature were used, covering a wide range of physical properties of liquids, packings and operating conditions. This new approach showed operating holdup as an important factor in gas liquid mass transfer.     

移动传感器随机事件捕获

移动传感器在入侵检测的应用研究中,感兴趣区域主要考虑的是特定形状,如圆形或矩形。由于这种限制,很多研究结论通用性差。研究了感兴趣区域是任何形状的一个环;基于移动传感器的速度,移动模式和数量,建立了一个随机模型;分析多个或单个移动传感器沿环检测的性能。在模型中,当所有移动传感器检测时,它们被置以恒定的速度周期性地沿环移动。对于多个移动传感器,它们的速度都相同。入侵事件的模式为每次入侵到达环上一个随机点,抵达后停留一个随机时间长度。根据移动传感器的数量,导出了移动传感器对入侵漏捕概率和首次捕获入侵所需平均时间的一般表达式。最后,评估了移动传感器的检测性能。     

复合形退火的随机聚类算法

为了解决传统聚类算法易陷入局部最优解的问题,提出了一种复合形退火的随机聚类算法。该方法通过在聚类过程中设置退火准则,并且将退火过程中的生成复合形部分引入随机化的复合形节点,从而在加速收敛的过程中实现了较低的算法复杂度。理论分析及仿真实验证明,该方法的聚类效果好于传统的K-均值聚类方法,并且计算复杂度比目前基于人工智能的方法低。     

Improvement of cyclodextrin glucanotransferase as an antistaling enzyme by error-prone PCR

In an effort to improve the properties of cyclodextrin glucanotransferase (CGTase) as an antistaling enzyme, error-prone PCR was used to introduce random mutations into a CGTase cloned from alkalophilic Bacillus sp. I-5 (CGTase I-5). A mutant CGTase[3-18] with the three mutations M234T, F259I and V591A was selected by agar plate assay. Sequence alignment of various CGTases indicated that M234 and F259 are located in the vicinity of the catalytic sites of the enzyme and V591 in the starch binding domain E. The cyclization activity of CGTase[3-18] was dramatically decreased by 10-fold, while the hydrolyzing activity was increased by up to 15-fold. These mutations near subsite +1 (M234T) and at subsite +2 (F259I) are likely to alter the enzyme activity in a concerted manner, promoting hydrolysis of substrate while retarding cyclization. The addition of CGTase[3-18] reduced the retrogradation rate of bread by as much as did the commercial antistaling enzyme Novamyl during 7-day storage at 4 degrees C. No cyclodextrin (CD) was detected in bread treated with CGTase[3-18], whereas 21 mg of CD per 10 g of bread was produced in bread treated with wild-type CGTase.     

Observer‐based H ∞ control for networked systems with bounded random delays and consecutive packet dropouts

This paper is concerned with the H _∞ control problem for a class of systems with bounded random delays and consecutive packet dropouts that exist in both sensor‐to‐controller channel and controller‐to‐actuator channel during data transmission. A new model is developed to describe possible random delays and packet dropouts by two groups of Bernoulli distributed stochastic variables. To avoid the state augmentation, a full‐order observer‐based feedback controller is designed via LMI approach. Based on the Lyapunov theory, a sufficient condition is provided to guarantee the closed‐loop networked system to be asymptotically mean‐square stable and achieve the prescribed H _∞ disturbance‐rejection‐attenuation level. The simulation examples illustrate the effectiveness of the proposed method. Copyright © 2013 John Wiley & Sons, Ltd.     

Response to walnut olfactory and visual cues by the parasitic wasp Diachasmimorpha juglandis

Diachasmimorpha juglandis is a specialist parasitoid attacking fly larvae in the genus Rhagoletis that feed exclusively on walnut fruit husks. In a free-foraging assay comparing response to uninfested, infested, and mechanically damaged fruits, we first determined that D. juglandis use host feeding damage on the fruit as a cue for host presence. In another free-foraging assay that used artificial walnut models and wind tunnel experiments, D. juglandis distinguished infested from uninfested fruits by using either olfactory or visual cues separately. However, the response rate of wasps in the wind tunnel was raised considerably when visual cues were also available. We analyzed the volatile compounds emitted by cohorts of uninfested, mechanically damaged, and infested fruits 1, 3, 5, 8, and 10 days after oviposition by flies into the infested fruits. Total volatile emissions did not differ significantly among treatments, but quantitative changes in volatiles distinguished infested fruits from uninfested and damaged fruits. The fact that parasitoids did not distinguish between infested and damaged fruits in assays where damage was visible indicates that they rely on visual cues when those are available.     

高矣物的特性对双水相相图和头孢氨苄及7-ADCA分配行为的影响

A series of ethylene oxide(EO)-propylene oxide (PO) random co-polymers (EOPO) were used to form aqueous two-phase systems (ATPS) with ammonium sulfate.Effects of EOPO′s properties on the phase separation behaviors and on the partition of cephalexin and 7-aminodesacetoxicephalosporanic acid(7-ADCA) in ATPS were investigated.Both the molar mass and molar ratio of EO to PO of EOPO could greatly influence partition behaviors of cephalexin and 7-ADCA as well as the binodal curve of ATPS. With the increase of molar mass of co-polymer or the decrease of molar ratio of EO to PO,the critical point of ATPS decreased,the binodal curve became more asymmetry,and both cephalexin and 7-ADCA followed the same tendency to partition into the polymer-poor bottom phase.The experimental results shows that it is feasible to partition cephalexin and 7-ADCA in either the polymer-rich top phase or the polymer-poor bottom phase by choosing a specific phase-forming EOPO.     

Flight and landing behavior ofTrypodendron lineatum (Coleoptera: Scolytidae) in response to different semiochemicals

The responses of the striped ambrosia beetle,Trypodendron lineatum (Olivier) (Coleoptera: Scolytidae), to modified drainpipe traps baited with the host attractant ethanol, the aggregation pheromone lineatin, both alone and in combination, were studied in a wind tunnel. Exposure of males to ethanol increased their frequency of steady, upwind flight; however, only lineatin was effective in inducing them to land on and enter the traps. In contrast, exposure of females to either ethanol or lineatin alone resulted in an increased frequency of trap landing and entry. Both compounds released simultaneously did not significantly increase the frequency of trap landing and entry for either sex. These responses are consistent with the life history strategies used by both sexes to seek and colonize suitable host material.