The fuzzy-logic control of active suspensions without suspension-gap degeneration

V tem prispevku uporabljamo model vozila s štirimi prostostnimi stopnjami z željo, da načrtamo in preverimo zmogljivosti aktivnega vzmetenja, ki ga logično mehko krmilimo, ne da bi kakorkoli zmanjšali delovno področje vzmetenja. Težnja k ničnemu premiku vzmetene mase utegne izničiti delovno razdaljo vzmetenja. Zato v tej raziskavi predlagamo nov pristop. Silostne izvršilnike vgradimo vzporedno z vzmetenjem. Osnovna zamisel, da predlagamo logično mehki krmilnik, izhaja iz dejstva, da je uspesen, iz moznosti, da taksen krmilnik uporabimo v vozilnih sistemih in iz moznosti, da s pomočjo logično mehkega algoritma premagamo upadanje zračnosti vzmetenja.Udobnost vožnje izboljšamo, tako da znižamo velikost gibov karoserije vozila. Poskakovanje karoserije in zibanje vozila modeliramo tako v časovnem (v primeru potovanja po nagnjeni stopničasti poti) kot v frekvenčnem prostoru. Rezultate simulacije primerjamo z rezultati pasivnega vzmetenja. Na koncu raziskave razpravljamo o zmogljivosti krmilnika s stalisča udobnosti voznje, o prednosti predlaganega pristopa in o izboljšanju zmogljivosti sistema.In this paper a four-degrees-of-freedom vehicle model is used in order to design and check the performance of fuzzy-logic-controlled (FLC) active suspensions without causing any degeneration in the suspensions\u27 working limits. Aiming at a zero displacement for a sprung mass might finish the suspensionsć working distance. Therefore, in this paper a new approach is proposed. The force actuators are mounted parallel to the suspensions. The main idea behind proposing a fuzzy-logic controller is its success, the ability to use these types of controllers on vehicle systems and the ability to overcome the suspension-gap degeneration problem within the fuzzy-control algorithm. The improvement in the ride comfort is achieved by decreasing the amplitudes of the motions of the vehicle body. The body bounce and the pitch motions of the vehicle are simulated in both the time domain, in the case of travelling over a ramp-step road profile, and in the frequency domain. The simulation results are compared with the results from passive suspensions. At the end of the paper , the performance of the controller, the advantage of theproposed approach and the improvement in the system performance are discussed in terms of the ride comfort

The interplay of within-species perceptual predispositions and experience during song ontogeny in zebra finches ( Taeniopygia guttata

Vocal acquisition in songbirds and humans shows many similarities, one of which is that both involve a combination of experience and perceptual predispositions. Among languages some speech sounds are shared, while others are not. This could reflect a predisposition in young infants for learning some speech sounds over others, which combines with exposure-based learning. Similarly, in songbirds, some sounds are common across populations, while others are more specific to populations or individuals. We examine whether this is also due to perceptual preferences for certain within-species element types in naive juvenile male birds, and how such preferences interact with exposure to guide subsequent song learning. We show that young zebra finches lacking previous song exposure perceptually prefer songs with more common zebra finch song element types over songs with less common elements. Next, we demonstrate that after subsequent tutoring, birds prefer tutor songs regardless of whether these contain more common or less common elements. In adulthood, birds tutored with more common elements showed a higher song similarity to their tutor song, indicating that the early bias influenced song learning. Our findings help to understand the maintenance of similarities and the presence of differences among birds' songs, their dialects and human languages

A dynamic, sex-specific expression pattern of genes regulating thyroid hormone action in the developing zebra finch song control system

The zebra finch (Taeniopygia guttata) song control system consists of several series of interconnected brain nuclei that undergo marked changes during ontogeny and sexual development, making it an excellent model to study developmental neuroplasticity. Despite the demonstrated influence of hormones such as sex steroids on this phenomenon, thyroid hormones (THs) - an important factor in neural development and maturation - have not been studied in this regard. We used in situ hybridization to compare the expression of TH transporters, deiodinases and receptors between both sexes during all phases of song development in male zebra finch. Comparisons were made in four song control nuclei: Area X, the lateral magnocellular nucleus of the anterior nidopallium (LMAN), HVC (used as proper name) and the robust nucleus of the arcopallium (RA). Most genes regulating TH action are expressed in these four nuclei at early stages of development. However, while general expression levels decrease with age, the activating enzyme deiodinase type 2 remains highly expressed in Area X, HVC and RA in males, but not in females, until 90days post-hatch (dph), which marks the end of sensorimotor learning. Furthermore, the L-type amino acid transporter 1 and TH receptor beta show elevated expression in male HVC and RA respectively compared to surrounding tissue until adulthood. Differences compared to surrounding tissue and between sexes for the other TH regulators were minor. These developmental changes are accompanied by a strong local increase in vascularization in the male RA between 20 and 30dph but not in Area X or HVC. Our results suggest that local regulation of TH signaling is an important factor in the development of the song control nuclei during the song learning phase and that TH activation by DIO2 is a key player in this process.status: publishe

Representative photomicrographs illustrating the distribution of chrondroitin sulfate immunoreactivity (Green signal) and of parvalbumin-immunoreactive cells (red signal) as observed in in parasagittal sections of male (C, C) and female (B, D) zebra finch brains.

<p>Panels A_B illustrate differences in HVC, panels C-D concern RA. The magnification bar in D (20 μm) also applies to all other panels.</p

Sex differences in the percentage of DAPI cells that were immunoreactive for parvalbumin (%PV-ir cells) or were surrounded by perineuronal nets (%PNN cells), in the percentage of PV-ir cells surrounded by PNN (%PV with PNN) and in the percentage of PNN surrounding PV-ir cells (%PNN with PV) in 4 song control nuclei, HVC (used as a proper name), RA (robust nucleus of the arcopallium), Area X of the basal ganglia and LMAN (lateral magnocellular nucleus of the anterior nidopallium).

<p>The figure shows the mean ± SEM of data in males (black bars) and females (open bars). Numbers of data in each case are listed in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0123199#pone.0123199.t001" target="_blank">Table 1</a>. ** = p<0.01, * = p<0.05 and (*) = 0.10</p

A dynamic, sex-specific expression pattern of genes regulating thyroid hormone action in the developing zebra finch song control system

The zebra finch (Taeniopygia guttata) song control system consists of several series of interconnected brain nuclei that undergo marked changes during ontogeny and sexual development, making it an excellent model to study developmental neuroplasticity. Despite the demonstrated influence of hormones such as sex steroids on this phenomenon, thyroid hormones (THs) - an important factor in neural development and maturation - have not been studied in this regard. We used in situ hybridization to compare the expression of TH transporters, deiodinases and receptors between both sexes during all phases of song development in male zebra finch. Comparisons were made in four song control nuclei: Area X, the lateral magnocellular nucleus of the anterior nidopallium (LMAN), HVC (used as proper name) and the robust nucleus of the arcopallium (RA). Most genes regulating TH action are expressed in these four nuclei at early stages of development. However, while general expression levels decrease with age, the activating enzyme deiodinase type 2 remains highly expressed in Area X, HVC and RA in males, but not in females, until 90days post-hatch (dph), which marks the end of sensorimotor learning. Furthermore, the L-type amino acid transporter 1 and TH receptor beta show elevated expression in male HVC and RA respectively compared to surrounding tissue until adulthood. Differences compared to surrounding tissue and between sexes for the other TH regulators were minor. These developmental changes are accompanied by a strong local increase in vascularization in the male RA between 20 and 30dph but not in Area X or HVC. Our results suggest that local regulation of TH signaling is an important factor in the development of the song control nuclei during the song learning phase and that TH activation by DIO2 is a key player in this process

Sex differences in the numbers of DAPI positive cells, in numbers of parvalbumin-immunoreactive (PV-ir) cells, of perineuronal nets (PNN) and in PV-ir cells surrounded by PN (PV+PNN), and in the intensity and percentage of surface covered by chondroitin sulfate-immunoreactive material (PNN intensity and PNN fraction area) in 4 song control nuclei and 3 auditory and 3 visual areas of the zebra finch brain.

<p>In each case the table lists the mean + SEM (in parentheses) of values in males and females, followed by the associated F and p obtained in the corresponding ANOVA (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0123199#sec002" target="_blank">methods</a> for detail of statistical analyses). The sample size in each case is indicated in a last column separately for all cell counts first and then for PNN intensity and fractional areas.</p><p>*** = p<0.001</p><p>** = p<0.01, = p<0.05 and</p><p>(*) = 0.10</p><p>Sex differences in the numbers of DAPI positive cells, in numbers of parvalbumin-immunoreactive (PV-ir) cells, of perineuronal nets (PNN) and in PV-ir cells surrounded by PN (PV+PNN), and in the intensity and percentage of surface covered by chondroitin sulfate-immunoreactive material (PNN intensity and PNN fraction area) in 4 song control nuclei and 3 auditory and 3 visual areas of the zebra finch brain.</p

Sex differences in the percentage of DAPI cells that were immunoreactive for parvalbumin (%PV-ir cells) or were surrounded by perineuronal nets (%PNN cells), in the percentage of PV-ir cells surrounded by PNN (%PV with PNN) and in the percentage of PNN surrounding PV-ir cells (%PNN with PV) in 3 auditory areas (Field L; the dorsal lateral mesencephalic nucleus, MLd; the medial nucleus of the dorsolateral thalamus, DLM), and 3 visual areas (the nucleus rotondus, ROT; the nucleus spiriformis lateralis, SpL; the nucleus subpretectalis, SP).

<p>The figure shows the mean ± SEM of data in males (black bars) and females (open bars). Numbers of data in each case are listed in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0123199#pone.0123199.t001" target="_blank">Table 1</a>. * = p<0.05 and (*) = 0.10</p