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1.
迷卡斗蟋鸣声的声学特征及其生物学意义   总被引:2,自引:0,他引:2  
首次利用计算机技术对迷卡斗蟋Velarifictorusmicado (Saussure)的鸣声特征及其生物学意义进行了研究。结果表明 :迷卡斗蟋在不同性比条件下 ,鸣声的声学特征不同。雄性独处时发出召唤声 ;2只以上的雄性在一起时会发出警戒声、挑战声或胜利声 ;1雄 1雌在一起时会发出欢迎声、求爱声 ,如果雌性不理会雄性的求爱时则会发出一种催促声。利用计算机 ,除了对人们用耳辨别的 3种鸣声 (召唤声、求偶声和争斗声 )进行客观记录外 ,还可以对以前所称的“求偶声”和“争斗声”进行更细致地分析和比较。根据其生物学意义 ,作者首次将其鸣声分为 7种 ,并对这 7种鸣声在功率谱和时域两方面进行了比较 ,发现迷卡斗蟋在不同行为下有不同的鸣声特征 ,传递不同的信息。  相似文献   
2.
In this article, the spectral features of first heart sounds (S1) and second heart sounds (S2), which comprise the mechanical heart valve sounds obtained after aortic valve replacement (AVR) and mitral valve replacement (MVR), are compared to find out the effect of mechanical heart valve replacement and recording area on S1 and S2. For this aim, the Welch method and the autoregressive (AR) method are applied on the S1 and S2 taken from 66 recordings of 8 patients with AVR and 98 recordings from 11 patients with MVR, thereby yielding power spectrum of the heart sounds. Three features relating to frequency of heart sounds and three features relating to energy of heart sounds are obtained. Results show that in comparison to natural heart valves, mechanical heart valves contain higher frequency components and energy, and energy and frequency components do not show common behaviour for either AVR or MVR depending on the recording areas. Aside from the frequency content and energy of the sound generated by mechanical heart valves being affected by the structure of the lungs–thorax and the recording areas, the pressure across the valve incurred during AVR or MVR is a significant factor in determining the frequency and energy levels of the valve sound produced. Though studies on native heart sounds as a non-invasive diagnostic method has been done for many years, it is observed that studies on mechanical heart valves sounds are limited. The results of this paper will contribute to other studies on using a non-invasive method for assessing the mechanical heart valve sounds.  相似文献   
3.
Sounds and vibrations play vital roles in intra- and inter-specific communication of many insect taxa, for sexual display, defence and social recruitment. In Lepidoptera, sound production occurs in larvae, pupae and adults and has evolved in response to selection of sexual or defensive traits. About 75% of the 6000 estimated lycaenid butterflies are associated with ants (termed “myrmecophilous species”) and many species produce acoustic emissions during pre-imaginal development. It was initially believed that these acoustic emissions were only produced by myrmecophilous species, but later studies showed that the ability to produce sounds may be universal among this butterfly family. The acoustic repertoire of the late-instar larvae of 12 lycaenid species (Polyommatinae and Lycaeninae), showing different degrees of interaction with ants, was analysed by investigating 12 acoustic parameters measured on the call fundamental unit (pulse). All samples produced species-specific calls whose spectra were characterized by harmonic frequency components. The inter-specific call diversity better reflects the level of association with ants than the taxonomic relationships between species. Our results support the hypothesis that the ability to emit acoustic signals is widespread in lycaenids, and that these emissions play a role in myrmecophilous interactions.  相似文献   
4.
研究了普氏蹄蝠(Hipposideros pratti)不同状态(飞行、悬挂)下的回声定位声波特征、形态特征和生态特征(捕食策略、捕食地和食物类型).结果表明,普氏蹄蝠的回声定位声波为CFFM型,在不同状态下,主频率有一定的差异,飞行状态的主频率略低于悬挂状态,表明普氏蹄蝠是利用多谱勒补偿效应来适应飞行速度引起的主频率变化,以进行准确的定位和有效的捕食;同时飞行状态下声脉冲时间、声脉冲间隔时间及FM带宽略低于悬挂状态,而声脉冲重复率和能率环略高于悬挂状态,表明普氏蹄蝠在不同状态下利用不同特征的声波进行捕食.由回声定位声波推断和野外观察可知,普氏蹄蝠可能在树冠周围以盘旋方式(在昆虫高峰期)或以捕蝇器式(在昆虫高峰期之后)捕食中等偏大的振翅昆虫(如甲虫).  相似文献   
5.
肺音信号分析系统研制   总被引:2,自引:0,他引:2  
本文研制的肺音信号检测与分析系统,具有肺音信号采集、肺音图显示、肺音信号的 时域分析等项功能。  相似文献   
6.
Sounds produced by male cichlids Metriaclima zebra during aggressive interactions were recorded to conduct a detailed analysis and to search for potential individual acoustic signatures. Fish from two different size groups (small and large individuals) were analysed. The two groups were significantly different for all acoustic variables considered; six of seven features demonstrated a significant interindividual variability and most of them were correlated with the size of the emitter. A cross-validated and permuted discriminant function analysis (pDFA) separated the two groups and correctly classified around 50% of the sounds to the correct individuals. Acoustic features that best distinguished among males were the instantaneous frequency of sounds and the modulation of pulse amplitude. These results suggest that acoustic signals could bear information about individual identity. The long-term stability of this signature is likely to be weak since the signature of a growing individual may change over time.  相似文献   
7.
目的:比较顺式阿曲库铵和阿曲库铵在小儿全麻中对气道功能的影响。方法:选取72名3-9岁患儿,男42例,女30例,采用随机表法将其分为观察组和对照组,每组36例。两组麻醉诱导都采用异丙酚,芬太尼,咪达唑仑。观察组使用顺式阿曲库铵0.15mg/kg,对照组组阿曲库铵0.5 mg/kg,比较两组小儿在插管后5 min、10 min、15 min、20 min患儿P_(ET)CO_2、P-PEAK、听诊呼吸音(粗、细湿啰音)、SPO_2变化四项指标来研究顺式阿曲库铵和阿曲库铵对呼吸系统的影响。结果:观察组注药后5 min、10 min、15 min、20 min时间点P_(ET)CO_2,P-PEAK变化趋势不明显,听诊呼吸音、SPO_2无明显变化(P0.05)。对照组在注药后的4个时间段P_(ET)CO_2、P-PEAK、听诊呼吸音、SPO_2有显著变化,随时间延长,P_(ET)CO_2,P-PEAK有明显增高,SPO_2逐渐下降情况(P0.05)。观察组和对照组相比,5 min、10 min、15 min、20 min各时间点观察组SPO_2高于对照组,PETCO_2、P-PEAK明显低于对照组,啰音发生的概率低于对照组,各时间点各项指标比较差异有统计学意义(P0.05)。结论:顺式阿曲库铵术中对小儿气道功能影响较小,肌松作用理想,可广泛应用于小儿临床麻醉。  相似文献   
8.
Calls emitted by the brown meagre Sciaena umbra (L., fam. Sciaenidae) were recorded at the Natural Marine Reserve of Miramare (Trieste, Italy) in seven nocturnal surveys (12-h continuous sampling) during the summer of 2009. Calls consist of pulses, with the main energy content below 2 kHz and mean peak frequency of c. 270 Hz. Pulses were short, with an average duration of 20 ms and a pulse period of 100 ms. Sounds lasted approximately 500 ms. Three types of sound patterns were recognized: irregular (I), regular (R) and the chorus (C). Their acoustic parameters are described showing that I, R and C differ in pulse duration, pulse peak frequency and pulse period. Occurrence of the three call types changes throughout the night: the R pattern occurred mainly at dawn and dusk, C predominated after nightfall, while I calls were produced sporadically during the whole nocturnal period. Our results indicate that S. umbra has a pronounced nocturnal rhythm in vocalizing behaviour and highlight how the diagnostic time–frequency pattern of S. umbra calls can be used to identify the species in the field. Considering that the abundance of S. umbra is currently declining, the information presented here will be relevant in developing non-invasive and low-cost monitoring acoustic systems for managing S. umbra conservation and fishery along the Mediterranean Sea.  相似文献   
9.
We examined sexual selection by Drosophila littoralis, D. montana, and D. ezoana females on male courtship sounds to determine whether the females use absolute or relative criteria when choosing their mates. Behavior of the females was observed, when they were courted by a single male producing normal sounds, or by a single wing-manipulated male producing abnormal sounds; and when they were courted by one or both of these males in a choice situation. The females usually accepted short-winged (but not wingless) males producing abnormal sounds, if they had no alternatives. However, if they heard the sound produced by a normal male, they rejected the deficient male. Drosophila littoralis and D. ezoana females selected between two wing-manipulated males with different wing areas. Our results suggest that the females choose their mates on the basis of relative criteria if the signals emitted by the courting males are within the range of acceptable cues.  相似文献   
10.
The aims of this study were to (i) assess the efficacy of passive acoustic monitoring (PAM) for detecting Arctic Charr at their spawning grounds and (ii) characterize the overall acoustic soundscape of these sites. PAM was carried out over three Arctic Charr spawning grounds in the UK, one lotic and two lentic. 24-h cycles of recordings were collected prior to and during the Arctic Charr spawning season, which was determined from data returns by simultaneous net monitoring. Acoustic analysis consisted of manual quantification of sound sources, Acoustic Complexity Index (ACI) calculation and spectral analysis in 1/3 octave band (SPL; dB re 1 μPa). In the lotic spawning ground, prior to the beginning of Arctic Charr spawning, SPL and ACI showed a restricted range of variation throughout the 24-h, while during spawning the night values of SPL and ACI were found to significantly increase, concurrently with the rate of gravel noise induced by fish spawning activities and fish air passage sounds. Both prior to and during the Arctic Charr run, the lentic soundscape was characterized by diel variation due to the daytime presence of anthropogenic noise and the night-time presence of insect calls, while only a few occurrences of fish air passage sounds and gravel noise were recorded. These findings suggest that PAM over Arctic Charr spawning grounds could provide meaningful information to be used in developing management plans for this threatened species, such as determining the location and time of arrival, diel pattern and length of spawning activities.  相似文献   
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