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To address the issue of the in-phase state of charge(SOC) unbalancing in a cascaded H-bridge battery energy storage system, this paper proposes a novel control strategy based on nearest level modulation(NLM). Through NLM, this paper first calculates the number of sub-modules needed, then adjusts the priority of sub-modules in different SOC by the charging state, so that the sub-modules with larger SOC deviation converge to the average value. Considering that sub-modules with a large SOC deviation participating in charging or discharging may bring distortion of the PCS output, limiting the number of sub-modules with large deviations during the charging or discharging is needed, so that the sub-modules with large SOC deviation and sub-modules close to average SOC cooperate in charging/discharging process to reduce the distortion of PCS output. The simulation result verified the correctness of the strategy.

Two conjugated polymers (PuIDTBD and PuIDTQ) with unsymmetric side chains have been prepared for polymer solar cells using two other polymers (PIDTBD and PIDTQ) with symmetric side chains as control compounds. The combination of methyl and 4-hexylphenyl side chains on the same bridged carbon can ensure good solubility, decrease π-π stacking distances, and bring proper miscibility with PC71BM simultaneously. Therefore, the corresponding polymer solar cells (PSCs) based on donor polymers with unsymmetric side chains exhibited enhanced short-circuit current density (JSC) and power conversion efficiency (PCE) compared with those of control polymers. The PIDTBD and PIDTQ based devices possessed low PCE of 2.13% and 1.48%, while PCEs of devices based on PuIDTBD and PuIDTQ were improved to 3.93% and 4.12%, respectively. The results demonstrate that unsymmetric side chain engineering of conjugated polymers is an effective approach to achieve high performance PSCs.

The characteristics of meteorological conditions and pollutant concentrations were analyzed based on two pollution episodes before and after city heating in Beijing during February to March of 2019. The backward trajectory and WRF-CAMx models were used to analyze the evolution of pollutants before and after city heating, and the influences of meteorological conditions, regional transport, and secondary transformation on the episodes were discussed. There was little difference in the average

Asymmetrical side chains were widely used in conjugated molecules, but related stereoisomeric phenomenan is rarely investigated. Herein, two stereoisomers based on ladder-type acceptor IDT-BT-R with asymmetrical side chains were synthesized and their properties were studied. Compared to cis-IDT-BT-R, trans-IDT-BT-R with centrosymmetrical structure showed stronger crystallinity and more ordered molecular packing. As a result, trans-IDT-BT-R based photovoltaic devices exhibited higher charge transport properties and superior power conversion efficiency (PCE) up to 9.43%.

Monitoring data were used to analyze the relationships among relative humidity (RH), visibility, and PM

Olanzapine is an atypical antipsychotic for the treatment of schizophrenia, in which memory impairment is a core deficit. The methods of positive and negative syndrome scale (PANSS), Wechsler memory scale-4th edition (WMS-IV) and event-related potential (ERP) were used to study the effects of olanzapine on the cognitive function in the first-episode schizophrenic patients. We performed multicentre, randomized, double-blind, placebo-controlled, parallel-group clinical trial to study the cognitive functioning in Han Chinese first-episode schizophrenic patients in a 12-week treatment regime with olanzapine (129 cases) or placebo (132 cases). The results showed that (1) the patients with first-episode schizophrenia showed significant deficits in the long-term memory, short-term memory, immediate memory and memory quotient by WMS-IV assessment, and decreases the total scores, positive symptoms, negative symptoms and general psychopathology by PANSS assessment; (2) olanzapine could significantly improve the PANSS scores including total scores, positive symptoms, negative symptoms and general psychopathology in the first-episode schizophrenic patients; (3) olanzapine could significantly improve the short-term memory, immediate memory and memory quotient in the first-episode schizophrenic patients; and (3) although the latencies of P(2), N(2) and P(3) were significantly prolonged, P(2) and P(3) amplitudes were decreased and the latencies of N(1) did not change, olanzapine did not influence any P(300) items in the first-episode schizophrenic patients. The data suggested that that olanzapine could improve cognitive process, such as memorizing and extraction of the information although there were many changes of cognitive functions in Han Chinese first-episode schizophrenic patients.

Oppositional defiant disorder (ODD) is a behavioral disorder of school-age population. It is well known that 5-HT dysfunction is correlated with impulsivity, which is one of the common characteristics of ODD. The enzyme tryptophan hydroxylase-2 (TPH-2) synthesizes 5-HT in serotonergic neurons of the midbrain raphe. The purposes of this study were to investigate the potential association of TPH-2 polymorphisms with susceptibility to ODD in a Han Chinese school population. Four polymorphisms (rs4570625, rs11178997, rs1386494 and rs7305115) of the TPH-2 gene were analyzed by using polymerase chain reaction and DNA microarray hybridization in a case–control study of 276 Han Chinese individuals (124 ODD and 152 controls). In single marker analyses,there was a significant difference in the genotype (χ 2 = 4.163, P = 0.041) and allele frequency (χ 2 = 3.930, P = 0.047) of rs1386494 between ODD and control groups. Haplotype analyses revealed higher frequencies of haplotypes TA (rs4570625-rs11178997), TAG (rs4570625-rs11178997-rs1386494), TAA (rs4570625-rs11178997-rs7305115) and TAGA (rs4570625-rs11178997-rs1386494-rs7305115), but lower frequencies of haplotypes GA (rs4570625-rs11178997) and GAG (rs4570625-rs11178997-rs1386494) in ODD compared to control groups. These findings suggest the role of these TPH-2 gene variants in susceptibility to ODD. Some haplotypes might be the risk factors for Chinese Han children with ODD, while others might be preventable factors.

A highly miniaturized simplified composite right/left handed (SCRLH) mushroom zeroth-order resonator (MZOR) is proposed for bandpass filter (BPF) design. By introducing the U slot etched around the metallic via, more flexible selection of the shunt inductance value can be achieved compared with the original one. As the length of U -slot increased, zeroth-order resonant frequency of the MZOR decreased, even 88% size reduction can be achieved. Finally, a bandpass filter based on the proposed MZOR is designed, fabricated and measured. The simulated and measured results are presented and good agreement is obtained.

A simplifled extended composite right/left-handed (SE- CRLH) transmission line (TL) is proposed for dual-band applications. The dual-band bandpass behavior is realized with a simplifled non-dual circuit with only two broadband balanced conditions. The dispersion relation and frequency response of SE-CRLH TL are analyzed by circuit analysis, Bloch-Floquet theorem, and full wave simulation. A demonstration of SE-CRLH structure is designed. The measurements are in agreement with simulations and theory.

A miniaturized ultra-wideband (UWB) bandpass fllter (BPF) with U-slot etched around the metallic via in the ground is proposed based on a simplifled composite right/left-handed transmission line (SCRLH TL) structure. The U-slot etched in the ground makes it feasible to reduce the overall size. A demonstration of FCC standard UWB bandpass fllter (BPF) is designed, fabricated and measured. Very good agreement is shown between measurement and simulation.

The lift and power requirements of a model dragonfly in forward flight are studied, using the method of numerically solving the Navier-Stokes equations. The graph of power against flight speed is U-shaped, suggesting that a dragonfly might have a preferred cruising speed. Considerable variation in the relative phase between fore- and hindwings results in only very small change in power requirement. This suggests theat the forewing-hingwing interaction is weak and furthermore, might explain why phase angles ranging from to are employed by dragonflies in hovering and forward flight.

SUMMARYThe aerodynamics and forewing-hindwing interaction of a model dragonfly in forward flight are studied, using the method of numerically solving the Navier-Stokes equations. Available morphological and stroke-kinematic parameters of dragonfly (Aeshna juncea) are used for the model dragonfly. Six advance ratios (J; ranging from 0 to 0.75) and, at each J, four forewing-hindwing phase angle differences(γd; 180°, 90°, 60° and 0°) are considered. The mean vertical force and thrust are made to balance the weight and body-drag, respectively, by adjusting the angles of attack of the wings, so that the flight could better approximate the real flight.At hovering and low J (J=0, 0.15), the model dragonfly uses separated flows or leading-edge vortices (LEV) on both the fore- and hindwing downstrokes; at medium J (J=0.30, 0.45), it uses the LEV on the forewing downstroke and attached flow on the hindwing downstroke; at high J (J=0.6, 0.75), it uses attached flows on both fore- and hindwing downstrokes. (The upstrokes are very lightly loaded and, in general, the flows are attached.)At a given J, at γd=180°, there are two vertical force peaks in a cycle, one in the first half of the cycle, produced mainly by the hindwing downstroke, and the other in the second half of the cycle, produced mainly by the forewing downstroke; atγ d=90°, 60° and 0°, the two force peaks merge into one peak. The vertical force is close to the resultant aerodynamic force[because the thrust (or body-drag) is much smaller than vertical force (or the weight)]. 55-65% of the vertical force is contributed by the drag of the wings.The forewing-hindwing interaction is detrimental to the vertical force (and resultant force) generation. At hovering, the interaction reduces the mean vertical force (and resultant force) by 8-15%, compared with that without interaction; as J increases, the reduction generally decreases (e.g. at J=0.6 and γd=90°, it becomes 1.6%). A possible reason for the detrimental interaction is as follows: each of the wings produces a mean vertical force coefficient close to half that needed for weight support, and a downward flow is generated in producing the vertical force; thus, in general, a wing moves in the downwash-velocity field induced by the other wing, reducing its aerodynamic forces.

In this letter, a compact and high selectivity dual-band dual-mode microstrip bandpass filter (BPF) with the source-load coupling is proposed using the single short-circuited stub-loaded stepped-impedance resonator.The resonator can generate two resonant modes in each band. The short-circuited stub at the central can only adjust the even mode resonant frequencies, whereas the odd mode ones are fixed. The resonator utilizes the odd and even mode resonators' fundamental resonant frequencies and second harmonic ones to generate the first and second passbands, respectively. Five transmission zeros are created near the passband edges and in the upper-stopband to improve the selectivity. Simulation and measurement results of the dual-band BPF operated at 1.575 and 5.2 GHz demonstrate that the proposed filter is feasible. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:79–81, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26508

In this paper, an improved Volterra series with physical knowledge for modeling RF power amplifiers is presented. The parameters of this model can be extracted in digital domain since the model is analyzed based on the envelope signals. To simplify the classical Volterra series, a physical feedback behavioral model is applied to describe power amplifiers. Considering the fading memory effect a new feedback form is presented. The pruned Volterra series is modified depending on the matching network theory to make this model more accurate.

To explore the changes and the clinical significance of 5-hydroxytryptamine (5-HT), dopamine (DA) levels in serum and cerebrospinal fluid (CSF) of patients with delayed encephalopathy (DEACMP) after acute carbon monoxide poisoning.The dynamic detection of 5-HT and DA levels in serum and CSF from 42 patients with DEACMP was performed with high performance liquid chromatography (HPLC). The condition changes of patients with DEACMP were analyzed with three types of scales: the activity of daily living scale (ADL), information memory concentration test (IMCT) and Hasegawa's dementia scale (HDS); these changes were compared with those from 38 other encephalopathy patients and 38 non-encephalopathy patients, respectively.Before treatment, the serum 5-HT and DA levels [(662.61 ± 178.50) and (155.74 ± 60.32) nmol/L, respectively] of DEACMP group were both significantly lower than those [(914.08 ± 198.04) and (225.70 ± 48.53) nmol/L] of non-encephalopathy group (P0.05); the serum DA level of DEACMP group was also significantly lower than that [(243.57 ± 66.94) nmol/L] of other encephalopathy group (P0.05); the serum 5-HT level of DEACMP group was not significantly different from that [(729.54 ± 299.87) nmol/L] of other encephalopathy group (P0.05). After treatment, the serum 5-HT and DA levels [(714.08 ± 170.47) and (192.18 ± 33.07 nmol/L, respectively)] of DEACMP group elevated to various extent, but only serum DA level was significantly higher than that before treatment (P0.05). Before treatment, the CSF 5-HT and DA levels of DEACMP group were significantly lower than those of non-encephalopathy group and those of other encephalopathy group (P0.05). After treatment, the CSF 5-HT level (232.44 ± 54.28 nmol/L) was similar to normal level and significantly higher than that before treatment (P0.05); the CSF DA level [(56.83 ± 12.85) nmol/L] of DEACMP group increased only slightly (P0.05). In DEACMP group, ADL score (50.64 ± 7.23), HDS score (8.55 ± 8.08) and IMCT score (4.95 ± 7.30) before treatment were significantly different from those (8.5 ± 8.08, 4.95 ± 7.30 and 15.64 ± 10.90) after treatment (P0.01). In DEACMP group, there wasa negative correlation between DA level changes and HDS score changes, when the DA levels and HDS scores before treatment were compared with those after treatment (P0.05).The dynamic changes of 5-HT and DA levels in serum and CSF of patients with DEACMP consisted basically with the patient's condition change. The dynamically detected 5-HT and DA levels can be used as the biological indicators to reflect the condition change and treatment effects of DEACMP patients.

A Miniaturized bandpass filter by utilizing complementary split ring resonators (CSRRs) array loaded halfmode substrate integrated waveguide (HMSIW) is proposed. By etching several CSRRs on the bottom metal plane of the HMSIW, a bandpass are realized below the cutoff frequency of the HMSIW. The application of the HMSIW and CSRR combination technique for the design of miniaturized bandpass filter is then illuminated by equivalent circuit model. A demonstration of band-pass filter are designed, fabricated and measured. Very good agreement is shown between measurement and simulation.

SUMMARYThe longitudinal stabilization control of a hovering model insect was studied using the method of computational fluid dynamics to compute the stability and control derivatives, and the techniques of eigenvalue and eigenvector analysis and modal decomposition, for solving the equations of motion (morphological and certain kinematical data of hoverflies were used for the model insect).The model insect has the same three natural modes of motion as those reported recently for a hovering bumblebee: one unstable oscillatory mode, one stable fast subsidence mode and one stable slow subsidence mode. Controllability analysis shows that although unstable, the flight is controllable. For stable hovering, the unstable oscillatory mode needs to be stabilized and the slow subsidence mode needs stability augmentation. The former can be accomplished by feeding back pitch attitude, pitch rate and horizontal velocity to produce \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \({\delta}{\bar{{\phi}}}\) \end{document} orδα 2; the latter by feeding back vertical velocity to produce δΦ or δα1 (δΦ, \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \({\delta}{\bar{{\phi}}}\) \end{document}, δα1and δα2 denote control inputs: δΦ and \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \({\delta}{\bar{{\phi}}}\) \end{document} represent changes in stroke amplitude and mean stroke angle, respectively; δα1represents an equal change whilst δα2 a differential change in the geometrical angles of attack of the downstroke and upstroke).

A super-ultra-wideband (UWB) bandpass filter (BPF) with fractional bandwidth of 138% and wide upper stopband is proposed based on a simplified composite right/left-handed transmission line (SCRLH TL) structure. The non-uniform periodical structure can help the SCRLH TL to realise a wider passband, while the complementary split-ring resonators are etched in the ground plane to achieve better performance of the upper stopband. In addition, the slots carved around the via make it feasible to reduce the overall size. The super-UWB BPF has been designed, fabricated and measured. Good agreement is shown between measurement and simulation.