Decentralised control for complex systems - An invited survey

© 2014 Inderscience Enterprises Ltd. With the advancement of science and technology, practical systems are becoming more complex. Decentralised control has been recognised as a practical, feasible and powerful tool for application to large scale interconnected systems. In this paper, past and recent results relating to decentralised control of complex large scale interconnected systems are reviewed. Decentralised control based on modern control approaches such as variable structure techniques, adaptive control and backstepping approaches are discussed. It is well known that system structure can be employed to reduce conservatism in the control design and decentralised control for interconnected systems with similar and symmetric structure is explored. Decentralised control of singular large scale systems is also reviewed in this paper

Study on the relationship between expression patterns of cocaine-and amphetamine regulated transcript and hormones secretion in porcine ovarian follicles

Background: Cocaine-and amphetamine regulated transcript (CART) is an endogenous neuropeptide, which is widespread in animals, plays a key role in regulation of follicular atresia in cattle and sheep. Among animal ovaries, CART mRNA was firstly found in the cattle ovaries. CART was localized in the antral follicles oocytes, granulosa and cumulus cells by immunohistochemistry and in situ hybridization. Further research found that secretion of E2 was inhibited in granulosa cells with a certain dose of CART, the effect depends on the stage of cell differentiation, sug- gesting that CART could play a crucial role in regulating follicle atresia. The objective of this study was to character- ize the CART expression model and hormones secretion in vivo and vitro in pig follicle granulosa cells, preliminarily studied whether CART have an effect on granulosa cells proliferation and hormones secretion in multiparous animals such as pigs. Methods: The expression levels of CART mRNA in granulosa cells of different follicles were analyzed using qRT-PCR technology. Immunohistochemistry technology was used to localize CART peptide. Granulosa cells were cultured in medium supplemented with different concentrations of CART and FSH for 168 h using Long-term culture system, and observed using a microscope. The concentration of Estradiol (E2) and progesterone (P) in follicular fluids of different test groups were detected by enzyme linked immunosorbent assay (ELISA). Results: Results showed that expression level of CART mRNA was highest in medium follicles, and significantly higher than that in large and small follicles (P \u3c 0.05). Immunohistochemical results showed that CART were expressed both in granulosa cells and theca cells of large follicles, while CART were detected only in theca cells of medium and small follicles. After the granulosa cells were cultured for 168 h, and found that concentrations of E2 increase with concen- trations of follicle-stimulating hormone (FSH) increase when the CART concentration was 0 μM. And the concentra- tion of FSH reached 25 ng/mL, the concentration of E2 is greatest. It shows that the production of E2 needs induction of FSH in granulosa cells of pig ovarian follicles. With the increasing of CART concentrations (0.01, 0.1, 1 μM), E2 con- centration has a declining trend, when the FSH concentrations were 25 and 50 ng/mL in the medium, respectively. Conclusions: These results suggested that CART plays a role to inhibit granulosa cells proliferation and E2 production, which induced by FSH in porcine ovarian follicular granulosa cells in vitro, but the inhibition effect is not significant. So we hypothesis CART maybe not a main local negative regulatory factor during porcine follicular development, which is different from the single fetal animals

H

This paper investigates the problem of H∞ fuzzy control for a class of nonlinear singular Markovian jump systems with time delay. This class of systems under consideration is described by Takagi-Sugeno (T-S) fuzzy models. Firstly, sufficient condition of the stochastic stabilization by the method of the augmented matrix is obtained by the state feedback. And a designed algorithm for the state feedback controller is provided to guarantee that the closed-loop system not only is regular, impulse-free, and stochastically stable but also satisfies a prescribed H∞ performance for all delays not larger than a given upper bound in terms of linear matrix inequalities. Then H∞ fuzzy control for this kind of systems is also discussed by the static output feedback. Finally, numerical examples are given to illustrate the validity of the developed methodology

A Novel method for monitoring urban dew condensation and its application

Rosa predstavlja unos vlage bitan za održavanje razine vode gradskih ekosustava. Rosu, koja je važan ekološki faktor gradskih ekosustava, lišće biljaka lako apsorbira i tako se opskrbljuje hranjivim tvarima (N, P i K). Osim toga, stvaranje rose važno je u pročišćavanju zraka. Ipak, ima malo internacionalno prihvaćenih standardnih metoda ili instrumenata trenutačno raspoloživih za mjerenje količine rose u urbanim ekosustavima, zbog male količine rose. U svrhu točnog mjerenja kondenzacije vodene pare noću i procjene učinaka stvrdnjavanja površine na tokove vode blizu površine, u radu se prati kondenzacija rose i kombinira rosa s indeksom površine lista te se predlaže nova metoda za praćenje i izračunavanje količine rose u različitim površinama urbanih ekoloških sustava. Grad Changchun u Kini uzet je kao primjer i predloženom metodom se promatrala kondenzacija rose u njegovim različitim funkcionalnim područjima u razdoblju u kojem nema smrzavanja (travanj 2016. do listopada 2016.). Konačno su se analizirali glavni meteorološki faktori koji utječu na kondenzaciju rose sumirajući pravilo kondenzacije vlage; uz to, dobio se intenzitet rose i njezina godišnja količina u različitim krajolicima. Rezultati pokazuju da su područja zelenog pojasa važna mjesta za nakupljanje rose. Redosljed krajolika po intenzitetu rose: područje zelenog pojasa, goli krajolik i krajolik s cestom (P < 0.01). Relativna vlažnost je glavni čimbenik od utjecaja na promjenu količine vodene pare. Količine rose se smanjuju idući od zelenog pojasa do golog krajolika i ceste i iznose 61.43, 0.56, i 1.23 mm. Prema omjeru za svaki krajolik godišnja količina rose je u Changchunu 22.98 mm. Sustav za mjerenje količine rose poboljšan je u urbanim dijelovima i dodana mu je količina dobivena kondenzacijom pare noću s različitih površina. Metoda daje teoretske reference za dalje istraživanje o vodenim tokovima blizu površine.Dew is crucial moisture input for the water balance of urban ecosystems. Dew, which is an important environmental factor of urban ecosystem, can be easily absorbed by plant leaves and provide nutrients (N, P, and K) to plants. Moreover, dew formation is important in air purification. However, few internationally accepted standard methods or instruments are currently available for measuring dew amount in urban ecosystems because of the small dew amount. In order to accurately measure the night water vapour condensation and evaluate the effects of surface hardening to near-surface water cycle, this study monitored dew condensation and combined dew with leaf area index, and a novel method was proposed for monitoring and calculating dew amount in different underlying surfaces in urban ecosystems. The Changchun City in China was considered as an example and the proposed method was used to observe dew condensation in different functional areas of the city during the frost-free period (April 2016 to October 2016). Finally, the main meteorological factors affecting dew condensation were analyzed by summarizing the rule of vapour condensation; moreover, dew intensity and annual dewfall of different landscapes were obtained. Results indicate that greenbelt landscapes are important sites for dew deposition. The landscapes of dew intensity, in descending order, are greenbelt landscape, bare landscape, and road landscape (P < 0.01). Relative humidity is the main factor affecting water vapour migration. Dewfall amounts in the greenbelt, road, and bare landscapes are 61.43, 0.56, and 1.23 mm, respectively. The annual dewfall is 22.98 mm in Changchun according to the proportion of each landscape. The dew-monitoring method system in urban area is improved and the wet deposition from vapour condensation of different surfaces underlying at night is added. The method provides theoretical reference for further research on revealing the near-surface water cycle

Radio AGN Selection and Characterization in Three Deep-Drilling Fields of the Vera C. Rubin Observatory Legacy Survey of Space and Time

The Australia Telescope Large Area Survey (ATLAS) and the VLA survey in the XMM-LSS/VIDEO deep field provide deep ($\approx 15$ ${\mu}$Jybeam$^{-1}$) and high-resolution ($\approx$ 4.5--8 arcsec) radio coverage of the three XMM-SERVS fields (W-CDF-S, ELAIS-S1, and XMM-LSS). These data cover a total sky area of 11.3 deg$^2$ and contain $\approx 11000$ radio components. Furthermore, about 3~deg$^2$ of the XMM-LSS field also has deeper MIGHTEE data that achieve a median RMS of 5.6 ${\mu}$Jy beam$^{-1}$ and detect more than 20000 radio sources. We analyze all these radio data and find source counterparts at other wavebands utilizing deep optical and IR surveys. The nature of these radio sources is studied using radio-band properties (spectral slope and morphology), and the IR-radio correlation. %and spectral energy distribution. Radio AGNs are selected and compared with those selected using other methods (e.g. X-ray). We found 1656 new AGNs that were not selected using X-ray and/or MIR methods. We constrain the FIR-to-UV SEDs of radio AGNs using {\sc cigale} and investigate the dependence of radio AGN fraction upon galaxy stellar mass and star-formation rate.Comment: 25 pages, 21+3 figures, 8+1 tables, MNRAS accepted (final version). The catalogues are available from https://personal.psu.edu/wnb3/xmmservs/zhu2023-tables-2023-04-12.tar.zi

Bounded real lemmas for positive descriptor systems

A well known result in the theory of linear positive systems is the existence of positive definite diagonal matrix (PDDM) solutions to some well known linear matrix inequalities (LMIs). In this paper, based on the positivity characterization, a novel bounded real lemma for continuous positive descriptor systems in terms of strict LMI is first established by the separating hyperplane theorem. The result developed here provides a necessary and sufficient condition for systems to possess H?H? norm less than ? and shows the existence of PDDM solution. Moreover, under certain condition, a simple model reduction method is introduced, which can preserve positivity, stability and H?H? norm of the original systems. An advantage of such method is that systems? matrices of the reduced order systems do not involve solving of LMIs conditions. Then, the obtained results are extended to discrete case. Finally, a numerical example is given to illustrate the effectiveness of the obtained results

Altered Functional and Causal Connectivity of Cerebello-Cortical Circuits between Multiple System Atrophy (Parkinsonian Type) and Parkinson’s Disease

Lesions of the cerebellum lead to motor and non-motor deficits by influencing cerebral cortex activity via cerebello-cortical circuits. It remains unknown whether the cerebello-cortical “disconnection” underlies motor and non-motor impairments both in the parkinsonian variant of multiple system atrophy (MSA-P) and Parkinson’s disease (PD). In this study, we investigated both the functional and effective connectivity of the cerebello-cortical circuits from resting-state functional magnetic resonance imaging (rs-fMRI) data of three groups (26 MSA-P patients, 31 PD patients, and 30 controls). Correlation analysis was performed between the causal connectivity and clinical scores. PD patients showed a weakened cerebellar dentate nucleus (DN) functional coupling in the posterior cingulate cortex (PCC) and inferior parietal lobe compared with MSA-P or controls. MSA-P patients exhibited significantly enhanced effective connectivity from the DN to PCC compared with PD patients or controls, as well as declined causal connectivity from the left precentral gyrus to right DN compared with the controls, and this value is significantly correlated with the motor symptom scores. Our findings demonstrated a crucial role for the cerebello-cortical networks in both MSA-P and PD patients in addition to striatal-thalamo-cortical (STC) networks and indicated that different patterns of cerebello-cortical loop degeneration are involved in the development of the diseases

The Most Obscured AGNs in the XMM-SERVS Fields

We perform X-ray spectral analyses to derive the characteristics (e.g., column density, X-ray luminosity) of ≈10,200 active galactic nuclei (AGNs) in the XMM-Spitzer Extragalactic Representative Volume Survey, which was designed to investigate the growth of supermassive black holes across a wide dynamic range of cosmic environments. Using physical torus models (e.g., Borus02) and a Bayesian approach, we uncover 22 representative Compton-thick (CT; NH > 1.5 × 1024 cm−2) AGN candidates with good signal-to-noise ratios as well as a large sample of 136 heavily obscured AGNs. We also find an increasing CT fraction (fCT) from low (z 0.75) redshift. Our CT candidates tend to show hard X-ray spectral shapes and dust extinction in their spectral energy distribution fits, which may shed light on the connection between AGN obscuration and host-galaxy evolution

The Most Obscured AGNs in the XMM-SERVS Fields

We perform X-ray spectral analyses to derive characteristics (e.g., column density, X-ray luminosity) of $\approx$10,200 active galactic nuclei (AGNs) in the XMM-Spitzer Extragalactic Representative Volume Survey (XMM-SERVS), which was designed to investigate the growth of supermassive black holes across a wide dynamic range of cosmic environments. Using physical torus models (e.g., Borus02) and a Bayesian approach, we uncover 22 representative Compton-thick (CT; $N_{\rm H} \;>\; 1.5\times10^{24}\; \rm cm^{-2}$) AGN candidates with good signal-to-noise ratios as well as a large sample of 136 heavily obscured AGNs. We also find an increasing CT fraction (\fct ) from low ($z<0.75$) to high ($z>0.75$) redshift. Our CT candidates tend to show hard X-ray spectral shapes and dust extinction in their SED fits, which may shed light on the connection between AGN obscuration and host-galaxy evolution.Comment: 12 pages, 9 figures, accepted for publication in Ap