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51.
52.
为准确识别管道系统运行工况,提高对油气管道突发事故的响应速度,综合提升管网安全管理水平,提出1种基于时序片段的油气管道运行工况识别方法。首先,构建基于概率分布的状态变化识别模型,提取油气管道中不同运行状态点;其次,建立基于时间序列片段的工况识别模型,快速识别不同时间长度内油气管道运行工况;最后,以国内某成品油管道为例进行方法验证。研究结果表明:该方法可有效识别成品油管道阀门开关状态、泵异常停机和阀门内漏3种运行工况。对比传统的识别方法,该方法可降低状态变化点的漏报率,提升管道运行工况识别的准确率。研究结果可为油气管道系统运行工况识别提供新的借鉴方法。 相似文献
53.
Hierarchical perception of fertility signals and nestmate recognition cues in two dolichoderine ants
Laurent Cournault Jean-Christophe de Biseau 《Behavioral ecology and sociobiology》2009,63(11):1635-1641
In social insects, queens are likely to “honestly” inform their nestmates of their presence and fertility status through pheromonal
communication. Cuticular hydrocarbons (CHCs) have been reported to be effective nestmate discriminators and strongly suspected
to act as fertility signals, at least in some species. The use of the same chemical bouquet (i.e., the CHC profile) to convey
two fundamentally different information seems puzzling. However, a recent threshold model proposes a hierarchy in the discriminating
processes, i.e., fertility signals can only be perceived if nestmate recognition has been reached (Le Conte and Hefetz, Annu
Rev Entomol 53:523–542, 2008). Here, we developed a simple behavioral bioassay based on chemical recruitment toward a queen placed outside the nest in
two dolichoderine ants (Linepithema humile and Tapinoma erraticum), which allowed us to investigate the interplay between fertility signaling and colonial recognition. Using queen corpses
of various origins (nestmates or aliens) and physiological states (fertile or infertile; mated or unmated), we demonstrated
that nestmate recognition cues clearly override fertility signals under our experimental conditions. Indeed, while nestmate
infertile queens were largely ignored by the workers, nestmate fertile queens (mated or not) induced worker recruitment, whereas
alien fertile queens did not and were aggressed by the workers. 相似文献
54.
This paper models the dissolved oxygen (DO) dynamics in the Orbetello lagoon as a function of the physico-chemical and ecological system variables, including the submerged vegetation, nutrients, and hydrodynamics. It should be viewed as the concluding sequel to a previous paper describing the dynamics of the lagoon ecosystem [Giusti, E., Marsili-Libelli, S., 2006. An integrated model for the Orbetello lagoon ecosystem, Ecol. Model. 196, 379–394] by introducing the missing DO dynamics. The model considers the oxygen demand originating from the decay of carbonaceous and nitrogenous compounds, as well as photosynthesis and natural reaeration by winds and currents as the oxygen producing processes. With a fixed-parameter set the model could accurately reproduce each single circadian DO cycle, but in the long run it failed to extend this fit and could not accommodate the large DO fluctuations induced by the seasonal variability. In order to enhance the model flexibility, a fuzzy pattern recognition algorithm was designed to classify the circadian DO patterns into four typical behaviours, related to the season, and estimate the corresponding parameters, with the overall model output being a fuzzy combination of these sets. The paper discusses several methods to patch the parameter sets and compares their performance in tracking long-term DO variations. A final assessment of the model validity is obtained by incorporating the whole DO dynamics (model, fuzzy pattern recognition and parameter combination) into the general lagoon model and producing a consistently correct series of DO daily distributions over a yearly cycle. Thus the paper contains both a practical and a methodological aspect. The practical one is the linking of all the lagoon dynamics to the dissolved oxygen kinetics in order to clarify to what extent macroalgae and macrophytes influence the oxygen balance. The methodological aspect consists of extending the validity of short-term models to long time-horizons through a patching technique supported by fuzzy pattern recognition. 相似文献
55.
基于神经网络的火灾探测系统 总被引:13,自引:1,他引:12
本文提出了一种基于神经网络的火灾探测方法,其对火灾的各种状态进行了识别,提高了早期发现火灾的能力,实验结果表明,该方法在火灾自动探测中是一种十分有效的方法。 相似文献
56.
Magne Friberg Namphung Vongvanich Anna-Karin Borg-Karlson Darrell J Kemp Sami Merilaita Christer Wiklund 《Behavioral ecology and sociobiology》2008,62(6):873-886
Animal courtship rituals are important for species recognition, and a variety of cues might be utilized to recognize conspecific
mates. In this paper, we investigate different species-recognition mechanisms between two sympatric butterfly sister species:
the wood white (Leptidea sinapis) and Real’s wood white (Leptidea reali). We show that males of both species frequently court heterospecific females both under laboratory and field conditions.
The long-lasting elaborate courtships impose energetic costs, since the second courtship of males that were introduced to
two subsequent conspecific females lasted on average only one fourth as long as the first courtship. In this paper, we demonstrate
that premating reproductive isolation is dependent on female unwillingness to accept heterospecific mates. We studied female
and male courtship behavior, chemical signaling, and the morphology of the sexually dimorphic antennae, one of the few male
traits visible for females during courtship. We found no differences in ultraviolet (UV) reflectance and only small differences
in longer wavelengths and brightness, significant between-species differences, but strongly overlapping distributions of male
L. sinapis and L. reali antennal morphology and chemical signals and minor differences in courtship behavior. The lack of clear-cut between-species
differences further explains the lack of male species recognition, and the overall similarity might have caused the long-lasting
elaborate courtships, if females need prolonged male courtships to distinguish between con- and heterospecific suitors. 相似文献
57.
Daniel T. Blumstein Louise Cooley Jamie Winternitz Janice C. Daniel 《Behavioral ecology and sociobiology》2008,62(3):457-468
We conducted four experiments to determine whether yellow-bellied marmots, Marmota flaviventris, discriminate among predator vocalizations, and if so, whether the recognition mechanism is learned or experience-independent.
First, we broadcast to marmots the social sounds of coyotes, Canis latrans, wolves, Canis lupus, and golden eagles, Aquila chrysaetos, as well as conspecific alarm calls. Coyotes and eagles are extant predators at our study site, while wolves have been absent
since the mid-1930s. In three follow-up experiments, we reversed the eagle call and presented marmots with forward and reverse
calls to control for response to general properties of call structure rather than those specifically associated with eagles,
we tested for novelty by comparing responses to familiar and unfamiliar birds, and we tested for the duration of predator
sounds by comparing a wolf howl (that was much longer than the coyote in the first experiment) with a long coyote howl of
equal duration to the original wolf. Marmots suppressed foraging and increased looking most after presentation of the conspecific
alarm call and least after that of the coyote in the first experiment, with moderate responses to wolf and eagle calls. Marmots
responded more to the forward eagle call than the reverse call, a finding consistent with a recognition template. Marmots
did not differentiate vocalizations from the novel and familiar birds, suggesting that novelty itself did not explain our
results. Furthermore, marmots did not differentiate between a wolf howl and a coyote howl of equal duration, suggesting that
the duration of the vocalizations played a role in the marmots’ response. Our results show that marmots may respond to predators
based solely on acoustic stimuli. The response to currently novel wolf calls suggests that they have an experience-independent
ability to identify certain predators acoustically. Marmots’ response to predator vocalizations is not unexpected because
25 of 30 species in which acoustic predator discrimination has been studied have a demonstrated ability to respond selectively
to cues from their predators. 相似文献
58.
Joseph J. Nocera Philip D. Taylor Laurene M. Ratcliffe 《Behavioral ecology and sociobiology》2008,62(11):1769-1777
Migrating animals face numerous mortality risks, such as novel predators with which they may not be accustomed. Most animals
can recognize predators innately; however, additional predator information can be collected to enhance familiarity. Because
migrating birds rarely participate in mobs, they may seek alternative information sources such as cues provided by other birds
that can provide information on predator location, identity, and degree of threat. We predicted that Nearctic–Neotropical
migrants (hereafter, “migrants”) would react to vocal antipredator cues (e.g., mob-calls) of species residing in areas through
which they migrate. To test this, we conducted experiments in Belize during spring migration, using playbacks of mob-calls
of black-capped chickadees (Poecile atricapillus) and blue-gray tanagers (Thraupis episcopus); tanagers are familiar to all birds in Belize; chickadees are novel to residents but familiar to migrants. This also allowed
us to assess response to novel and out-of-context antipredator signals. Resident birds did not respond to novel chickadee
mob-calls, but did respond to familiar tanager calls. Birds overwintering south of our study area, which were migrating during
our study, responded most strongly to chickadee playbacks. Conversely, individuals of species that include our study area
in their winter range did not respond to either playback. This is the first evidence that birds react to vocal antipredator
cues during migration, which may be a strategy used by migrants to learn about predators. Although residents failed to recognize
a foreign cue, migrating birds responded most strongly to the out-of-context chickadee cue, associated with breeding grounds
>2,000 km northward.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
59.
Margaret J. Couvillon Francis L.W. Ratnieks 《Behavioral ecology and sociobiology》2008,62(7):1099-1105
In group-level recognition, discriminators use sensory information to distinguish group members and non-members. For example,
entrance guards in eusocial insect colonies discriminate nestmates from intruders by comparing their odour with a template
of the colony odour. Despite being a species-rich group of eusocial bees closely related to the honey bees, stingless bee
nestmate recognition is a relatively little-studied area. We studied Frieseomelitta varia, a common Brazilian species of stingless bee known as marmelada. By measuring the rejection rates of nestmate and non-nestmate
worker bees by guards, we were able to show that guards became significantly less accepting (from 91 to 46%) of nestmates
that had acquired odour cues from non-nestmate workers; however, guards did not become significantly more accepting (from
31 to 42%) of non-nestmates that had acquired equivalent amounts of odour cues from the guard’s nestmates. These data strongly
suggest that guards use an “undesirable–absent” system in recognition, whereby incoming conspecific workers are only accepted
if undesirable cues are absent, despite the presence of desirable cues. We suggest that an undesirable–absent system is adaptive
because robbing by conspecifics may be an important selective factor in F. varia, which would lead to selection for a non-permissive acceptance strategy by guards. 相似文献
60.
以浦阳江流域(浦江县段)为研究区,从流域面源污染空间特征入手,提出浦阳江流域岸边带建设的重点区域。采用DPeRS面源污染负荷估算模型,具体分析了2018年浦阳江流域面源污染负荷空间分布特征,并采用面向对象方法提取了岸线和河流生态缓冲带土地覆盖类型,以汇水区为单元,结合面源污染估算结果识别了浦阳江流域河流生态缓冲带重点区。结果表明:浦阳江流域中部和中北部地区面源污染排放负荷较高,面源污染入河负荷高值区主要集中于中下游地区;该流域31个汇水区中,TN和NH4+-N重点汇水区有17个,主要分布在流域的中部和东北部;TP和COD重点汇水区有12个,集中分布于流域中部;浦阳江流域河流生态缓冲带范围内,植被类型和非植被类型面积占比分别为65.49%和34.51%,其中耕地面积占比29.36%,建筑用地占比11.89%;综合浦阳江流域面源污染重点汇水区和河流生态缓冲带现状遥感提取结果,筛选出的重点区包括下游地区的7号汇水区和中游地区的18~25号汇水区所在的河流生态缓冲带。今后,可针对其重点区域设计生态防护工程,也应结合源头减量、过程拦截、末端消纳与资源循环利用的防控策略,综合削减面源污染物入河量。 相似文献