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A novel topology with controllable wideband baseband impedance for power amplifiers

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 308-315页

作者： yao yao Zhijiang DAI Mingyu LI School of Intelligent Technology and Engineering Chongqing University of Science and TechnologyChongqing400065China School of Microelectronics and Communication Engineering Chongqing UniversityChongqing400065China

This paper presents a novel topology to control the baseband impedance of a power amplifier(PA)to avoid performance deterioration in concurrent dual-band mode.This topology can avoid pure resonance of capacitors and inductors LC,which leads to a high impedance at some frequency points.Consequently,it can be applied to transmitters that are excited by broadband signals.In particular,by adjusting the circuit parameters and increasing stages,the impedance of the key frequency bands can be flexibly controlled.A PA is designed to support this design idea.Its saturated output power is around 46.7 dBm,and the drain efficiency is>68.2%(1.8-2.3 GHz).Under concurrent two-tone excitation,the drain efficiency reaches around 40%even under 5.5 dB back-off power with the tone spacing from 10 MHz to 500 MHz.These results demonstrate that the proposed topology is capable of controlling wideband baseband impedance.

关键词： Baseband impedance Concurrent dual-band Power amplifier

New progress of small-molecule drugs in the treatment of inflammatory bowel disease

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Chinese Medical Journal 2024年第5期137卷 556-558页

作者： Dongying yao Zhihua Ran Department of Gastroenterology Zhou Pu Hospital affiliated to Shanghai University of Health&Medical SciencesShanghai 201318China

With the advent of small-molecule drugs,treatment of inflammatory bowel disease(IBD)has reached a new stage.In contrast to biologics,small-molecule drugs can be made into oral dosage forms with a short half-life and are suitable for administration 1–2 times a day.Small-molecule drugs work by inhibiting the transmission of key intracellular signaling pathways in the pathogenesis of ulcerative colitis(UC)and Crohn’s disease(CD)[Figure 1].They do not induce anti-drug antibodies in patients or lead to loss of response after treatment.

关键词： drugs treatment inflammatory

Fresh-Keeping Decision and Coordination of Fresh Agricultural Product Supply Chain Considering Carbon Cap-and-Trade under Different Dominance

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Journal of Systems Science and Systems Engineering 2024年第1期33卷 30-51页

作者： Yang Yang Guanxin yao China Institute for Agricultural Equipment Industrial Development Jiangsu UniversityZhenjiang212013China Jiangsu Modern Logistics Research Base Yangzhou UniversityYangzhou225009China

In the context of low carbon,this paper discussed the impact of the carbon cap-and-trade policy on the fresh-keeping decision-making of two-echelon fresh agricultural product supply chains under different dominance,and designed cost-sharing contracts to coordinate the supply chain of fresh agricultural products dominated by suppliers and retailers respectively.The results showed that:dominance has no effect on the fresh-keeping decision and total revenue of fresh agricultural product supply chain,but it affects the internal income distribution,and dominance does not always bring more benefits;the implementation of carbon cap-and-trade reduces the fresh-keeping decision-making of fresh agricultural products supply chain and reduces the free-rider income of followers;the role of higher carbon trading price is twofold,which not only brings about the speculation of leading enterprises,but also promotes the application of low-carbon technologies;consumers’high preference for freshness,low-cost and high-efficiency low-carbon technology are all conducive to improving the fresh-keeping efforts and benefits of the supply chain;cost-sharing contracts can coordinate the supply chain of fresh agricultural products.

关键词： Dominant power carbon cap-and-trade policy fresh agricultural product supply chain fresh-keeping decision-making

Analysis of influencing factors of anxiety and depression in patients with periodontitis

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World Journal of Psychiatry 2024年第1期14卷 141-147页

作者： yao Kong Department of Stomatology Xinxiang Central HospitalXinxiang 453000Henan ProvinceChina

BACKGROUND Periodontitis is a chronic oral disease caused by pathogenic microorganisms that corrode tooth tissue,form periodontal pockets,absorb alveolar bone,and finally lead to tooth loss.During treatment,patients are prone to anxiety,tension,and other negative emotions,which affect their ability to face the disease and may also lead to aggravation of the original condition and affect oral health.Therefore,it is important to improve the negative psychology of patients with periodontitis to clarify the factors that may lead to negative psychological emotions.AIM To investigate the risk factors that may lead to anxiety and depression in patients with periodontitis.METHODS One hundred patients with periodontitis were selected between March 2022 and March 2023 at our hospital.All patients were assessed with the Zung Self-rating Depression Scale(SDS)(≥53 points indicate a depressive state)and Zung Selfrating Anxiety Scale(SAS)(≥50 points indicates an anxious state).In this study,patients who experienced anxiety or depression were included in the occurrence group and those without anxiety or depression were included in the nonoccurrence group.The baseline data of the two groups were compared to explore the risk factors for anxiety and depression in patients with periodontitis.RESULTS A total of 100 patients with periodontitis were included in this study.According to the SDS,38 patients(38.00%)developed depression,with an average SDS score of(68.52±5.85)points.According to the SAS,40 patients(40.00%)developed anxiety,and the average SAS score was(72.15±4.15)points.In this study,56 patients with anxiety or depression were included.Compared with the nonoccurrence group,the occurrence group had higher ages(≥60 years),lower level of hope(low level),educational level(high school or below),disease perception(poor),and sleep disorder(yes).The negative coping dimension scores of the simplified coping style questionnaire(SCSQ)and Dental Fear Scale(DFS)in the occurrence group were higher,whereas the score of the positive coping

关键词： Periodontitis Anxiety Depression Mental state Influencing factor

Limits of Uneven Battery Power in Modular Multilevel Converter-based Battery Energy Storage Systems

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 686-695页

作者： yao Pan Xiaofeng Sun Wei Zhao Xin Li yao Cai Institute of Electrical Engineering Yanshan UniversityQinhuangdao 066004China

For modular multilevel converter-based battery energy storage systems (MMC-BESS), uneven power among batteries of SMs will be deduced by battery aging, battery fault, etc., which will degrade performance and even lead to system failure. For maintaining the balance of capacitor voltage, this paper analyzes the limits of the uneven power of batteries, which are presented as the current limits in this paper. According to analysis, an analytical method is proposed that only the dc and fundamental frequency components of the arm current are used to calculate current limits. With the current limits it is able to evaluate the reasonability of power distribution among batteries. Meanwhile, increase of fundamental frequency component will enhance the current limits, and the dc component determines the size relationship between the absolute values of the upper and lower current limits. Finally, simulation model and experiment prototype are built for verifying the theoretical analysis and current limits calculation method, and satisfactory results are provided.

关键词： Arm current balance of capacitor voltage current limits MMC-BESS uneven power

Reinforcement learning based adaptive control for uncertain mechanical systems with asymptotic tracking

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Defence Technology（防务技术） 2024年第4期34卷 19-28页

作者： Xiang-long Liang Zhi-kai yao yao-wen Ge Jian-yong yao School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China College of Automation&College of Artificial Intelligence Nanjing University of Post and TelecommunicationNanjing210023China

This paper mainly focuses on the development of a learning-based controller for a class of uncertain mechanical systems modeled by the Euler-Lagrange formulation.The considered system can depict the behavior of a large class of engineering systems,such as vehicular systems,robot manipulators and satellites.All these systems are often characterized by highly nonlinear characteristics,heavy modeling uncertainties and unknown perturbations,therefore,accurate-model-based nonlinear control approaches become unavailable.Motivated by the challenge,a reinforcement learning(RL)adaptive control methodology based on the actor-critic framework is investigated to compensate the uncertain mechanical dynamics.The approximation inaccuracies caused by RL and the exogenous unknown disturbances are circumvented via a continuous robust integral of the sign of the error(RISE)control approach.Different from a classical RISE control law,a tanh(·)function is utilized instead of a sign(·)function to acquire a more smooth control signal.The developed controller requires very little prior knowledge of the dynamic model,is robust to unknown dynamics and exogenous disturbances,and can achieve asymptotic output tracking.Eventually,co-simulations through ADAMS and MATLAB/Simulink on a three degrees-of-freedom(3-DOF)manipulator and experiments on a real-time electromechanical servo system are performed to verify the performance of the proposed approach.

关键词： Adaptive control Reinforcement learning Uncertain mechanical systems Asymptotic tracking

Lesson Learned from COVID-19 Retrospective Study: An Entropy-Based Clinical-Interpretable Scorecard for Mortality Risk Control at ICU Admission

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Tsinghua Science and Technology 2024年第1期29卷 34-45页

作者： Chong yao Chonghui Huangqi Anpeng Huang Laboratory of Network Information Security Beihang UniversityBeijing 100191China Andrew and Erna Viterbi School of Engineering University of Southern CaliforniaLos AnglesCA 90089USA Beijing Goodwill Information and Technology Co. Ltd.and Mobile Health LaboratoryPeking UniversityBeijing 100871China

With severe acute respiratory syndrome coronavirus 2 spreading globally and causing 2019 coronavirus disease(COVID-19),a challenge that we unprepared for was about how to optimally plan and distribute limited top-medical resources for patients in need of urgent care.To address this challenge,physicians desperately needed a scientific tool to methodically differentiate between cases with varying severity.In this study,the unique data of COVID-19 intensive care unit(ICU)patients provided by the national medical team in Wuhan were classified into discrete and continuous variable types.All continuous data were discretized using an entropy-based method and transformed into serial information margins,in which each information margin is related to a specific symptom or clinical meaning.Finally,all these native and processed discrete data were used to configure a readable scorecard through logistic regression,which is the desired scientific tool aforementioned.A total of 322 ICU patients(age:[median:64,interquartile range:54-75],males:178[55.28%],and death:72[22.36%])were included in the study.Probabilities of mortality in COVID-19 patients can be evaluated using a scorecard model(calibration slope:1.343,Brier:0.048,Dxy=0.972,and population stability index=0.071),with desired model performances(accuracy=0.948,area under curve=0.99,sensitivity=1,and specificity=0.939).This new model can interpret clinical meanings from complex data,and compare it with existing machine learning methods through a black-box mechanism.This new data-information model answers a critical question of how a computing algorithm produces clinically meaningful results that will help physicians logically allocate medical resources for COVID-19 patients.Notably,this tool has limitations,giving that this research is a retrospective study.Hopefully,this tool will be tested further and optimized for adaptation to similar clinical cases in the future.

关键词： COVID-19 scorecard clinical-interpretable machine learning ICU admission control

Expression Recognition Method Based on Convolutional Neural Network and Capsule Neural Network

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Computers, Materials & Continua 2024年第4期79卷 1659-1677页

作者： Zhanfeng Wang Lisha yao School of Computer Science and Artificial Intelligence Chaohu UniversityHefei238000China School of Big Data and Artificial Intelligence Anhui Xinhua UniversityHefei230088China

Convolutional neural networks struggle to accurately handle changes in angles and twists in the direction of images,which affects their ability to recognize patterns based on internal feature levels. In contrast, CapsNet overcomesthese limitations by vectorizing information through increased directionality and magnitude, ensuring that spatialinformation is not overlooked. Therefore, this study proposes a novel expression recognition technique calledCAPSULE-VGG, which combines the strengths of CapsNet and convolutional neural networks. By refining andintegrating features extracted by a convolutional neural network before introducing theminto CapsNet, ourmodelenhances facial recognition capabilities. Compared to traditional neural network models, our approach offersfaster training pace, improved convergence speed, and higher accuracy rates approaching stability. Experimentalresults demonstrate that our method achieves recognition rates of 74.14% for the FER2013 expression dataset and99.85% for the CK+ expression dataset. By contrasting these findings with those obtained using conventionalexpression recognition techniques and incorporating CapsNet’s advantages, we effectively address issues associatedwith convolutional neural networks while increasing expression identification accuracy.

关键词： Expression recognition capsule neural network convolutional neural network

Icariin attenuates vascular endothelial dysfunction by inhibiting inflammation through GPER/Sirt1/HMGB1 signaling pathway in type 1 diabetic rats

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Chinese Journal of Natural Medicines 2024年第4期22卷 293-306页

作者： yao Wenhui TAO Rongpin WANG Kai DING Xuansheng School of Basic Medicine and Clinical Pharmacy China Pharmaceutical UniversityNanjing211198China

Icariin, a flavonoid glycoside, is extracted from Epimedium. This study aimed to investigate the vascular protective effects of icariin in type 1 diabetic rats by inhibiting high-mobility group box 1 (HMGB1)-related inflammation and exploring its potential mechanisms. The impact of icariin on vascular dysfunction was assessed in streptozotocin (STZ)-induced diabetic rats through vascular reactivity studies. Western blotting and immunofluorescence assays were performed to measure the expressions of target proteins. The release of HMGB1 and pro-inflammation cytokines were measured by enzyme-linked immunosorbent assay (ELISA). The results revealed that icariin administration enhanced acetylcholine-induced vasodilation in the aortas of diabetic rats. It also notably reduced the release of pro-inflammatory cytokines, including interleukin-8 (IL-8), IL-6, IL-1β, and tumor necrosis factor-alpha (TNF-α) in diabetic rats and high glucose (HG)-induced human umbilical vein endothelial cells (HUVECs). The results also unveiled that the pro-inflammatory cytokines in the culture medium of HUVECs could be increased by rHMGB1. The increased release of HMGB1 and upregulated expressions of HMGB1-related inflammatory factors, including advanced glycation end products (RAGE), Toll-like receptor 4 (TLR4), and phosphorylated p65 (p-p65) in diabetic rats and HG-induced HUVECs, were remarkably suppressed by icariin. Notably, HMGB1 translocation from the nucleus to the cytoplasm in HUVECs under HG was inhibited by icariin. Meanwhile, icariin could activate G protein-coupled estrogen receptor (GPER) and sirt1. To explore the role of GPER and Sirt1 in the inhibitory effect of icariin on HMGB1 release and HMGB-induced inflammation, GPER inhibitor and Sirt1 inhibitor were used in this study. These inhibitors diminished the effects of icariin on HMGB1 release and HMGB1-induced inflammation. Specifically, the GPER inhibitor also negated the activation of Sirt1 by icariin. These findings suggest that icariin activates GPER and increases the exp

关键词： Icariin Diabetes Inflammation Vascular endothelial dysfunction GPER HMGB1