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AI Facilitates the Construction and Practice of the“Project-Guided and Task-Driven”Teaching Model:Taking“The Working Process of Open-Loop Control Systems”as an Example
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作者 Xueming Peng 《Journal of Contemporary Educational Research》 2025年第10期270-276,共7页
Addressing issues such as the disconnect between theory and practice and low student engagement in control system education,this paper uses the course“The Working Process of Open-Loop Control Systems”as a case study... Addressing issues such as the disconnect between theory and practice and low student engagement in control system education,this paper uses the course“The Working Process of Open-Loop Control Systems”as a case study to explore the integration of AI technology with the“project-guided and task-driven”teaching model.By constructing a four-dimensional teaching framework of“situation-task-activity-evaluation,”AI tools are embedded in project practices such as the construction of a mechanical timed flower watering device and the optimization of a digital timed flower watering device,achieving precision,interactivity,and personalization in the teaching process.Teaching practice demonstrates that this model significantly enhances students’technical awareness,materialization capabilities,and engineering thinking,providing a reference for the teaching reform of technical courses in high school education. 展开更多
关键词 AI technology Project-guided TASK-DRIVEN open-loop control system Technical education
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Gain adaptive tuning method for fiber Raman amplifier based on two-stage neural networks and double weights updates
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作者 MU Kuanlin WU Yue 《Optoelectronics Letters》 2025年第5期284-289,共6页
We present a gain adaptive tuning method for fiber Raman amplifier(FRA) using two-stage neural networks(NNs) and double weights updates. After training the connection weights of two-stage NNs separately in training ph... We present a gain adaptive tuning method for fiber Raman amplifier(FRA) using two-stage neural networks(NNs) and double weights updates. After training the connection weights of two-stage NNs separately in training phase, the connection weights of the unified NN are updated again in verification phase according to error between the predicted and target gains to eliminate the inherent error of the NNs. The simulation results show that the mean of root mean square error(RMSE) and maximum error of gains are 0.131 d B and 0.281 d B, respectively. It shows that the method can realize adaptive adjustment function of FRA gain with high accuracy. 展开更多
关键词 gain adaptive tuning connection weights error predicted target gains training connection weights unified nn gain adaptive tuning method double weights updates fiber raman amplifier fra
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Perifornical UCN3 Neurons Regulate Overeating-Induced Weight Gain
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作者 Shanshan Lu Xinran Zhang +8 位作者 Wanqi Chen Baofang Zhang Haiyang Jing Yunlong Xu Fengling Li Chenyu Jiang Gaowei Chen Xiaofei Deng Yingjie Zhu 《Neuroscience Bulletin》 2025年第6期1103-1108,共6页
Dear Editor,Obesity is an increasingly prevalent global metabolic disorder,yet effctive long-term interventions remain elusive.Recent studies have highlighted a novel peptide,Urocortin 3(UCN3),which shows potential fo... Dear Editor,Obesity is an increasingly prevalent global metabolic disorder,yet effctive long-term interventions remain elusive.Recent studies have highlighted a novel peptide,Urocortin 3(UCN3),which shows potential for obesity intervention[1]. 展开更多
关键词 weight gain OVEREATING UROCORTIN OBESITY
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Path of Enhancing the Sense of Gain Among Community Residents in Island Tourism Destinations in the Context of Culture and Tourism Integration:A Case Study of Weizhou Island
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作者 FANG Changgan CAO Yang 《Journal of Landscape Research》 2025年第1期74-80,84,共8页
Weizhou Island,located in Beihai,Guangxi Province,is recognized as the largest paleovolcanic island in China,characterized by its relatively young geological age.The development of island tourism has progressively est... Weizhou Island,located in Beihai,Guangxi Province,is recognized as the largest paleovolcanic island in China,characterized by its relatively young geological age.The development of island tourism has progressively established it as a significant tourist attraction within Beihai,transforming the area into a prominent leisure and tourism resort.As tourism on Weizhou Island continues to develop both in scope and in depth,it has increasingly influenced the sense of gain among the local community residents.Currently,in alignment with the strategic objective of achieving common prosperity,it is crucial to comprehend and enhance the sense of gain experienced by residents in island tourism destinations,as this is vital for the achievement of this overarching goal.Taking the residents of Weizhou Island in Beihai as the subjects,this paper constructs their sense of gain related to tourism,employing grounded theory.It posits that the residents’sense of gain comprises four primary dimensions:sense of economic gain,sense of social gain,sense of cultural gain,and sense of environmental gain.Additionally,the paper examines the factors that influence these dimensions.Based on this foundation,effective strategies are proposed to enhance the sense of gain among community residents in island tourism destinations,thereby promoting the sustainable development of island tourism. 展开更多
关键词 Sense of gain Island tourism Weizhou Island Beihai Sustainable development
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Vibration-induced bias error reduction using loop gain compensation for high-precision fiber optic gyroscopes
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作者 CHEN Heyu QIN Xuexin +2 位作者 XIE Huan KONG Linghai ZHENG Yue 《Journal of Systems Engineering and Electronics》 2025年第1期224-232,共9页
Vibration-induced bias deviation,which is generated by intensity fluctuations and additional phase differences,is one of the vital errors for fiber optic gyroscopes(FOGs)operating in vibration environment and has seve... Vibration-induced bias deviation,which is generated by intensity fluctuations and additional phase differences,is one of the vital errors for fiber optic gyroscopes(FOGs)operating in vibration environment and has severely restricted the applications of high-precision FOGs.The conventional methods for suppressing vibration-induced errors mostly concentrate on reinforcing the mechanical structure and optical path as well as the compensation under some specific operation parameters,which have very limited effects for high-precision FOGs maintaining performances under vibration.In this work,a technique of suppressing the vibration-induced bias deviation through removing the part related to the varying gain from the rotation-rate output is put forward.Particularly,the loop gain is extracted out by adding a gain-monitoring wave.By demodulating the loop gain and the rotation rate simultaneously under distinct frequencies and investigating their quantitative relationship,the vibrationinduced bias error is compensated without limiting the operating parameters or environments,like the applied modulation depth.The experimental results show that the proposed method has achieved the reduction of bias error from about 0.149°/h to0.014°/h during the random vibration with frequencies from20 Hz to 2000 Hz.This technique provides a feasible route for enhancing the performances of high-precision FOGs heading towards high environmental adaptability. 展开更多
关键词 vibration-induced error fiber optic gyroscope(FOG) loop gain
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Diversity Gain of an Interweave Cognitive MIMO Wire-Tap Channel
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作者 Atefeh Roostaei Mostafa Derakhtian 《China Communications》 2025年第9期162-181,共20页
The quality of spectrum sensing plays a significant role in determining the outage probability during the data transmission phase in an interweave cognitive radio network.If the secondary user(SU)fails to detect the p... The quality of spectrum sensing plays a significant role in determining the outage probability during the data transmission phase in an interweave cognitive radio network.If the secondary user(SU)fails to detect the primary user(PU)activity,it can re-sult in interference that limits the system performance.Additionally,since the wireless medium is broadcast in nature,there is a risk of eavesdroppers intercepting the cognitive users’data.Therefore,it is crucial to consider secrecy in the system analysis.In this paper,we analyze the secrecy outage probability(SOP)at the secondary receiver and derive the secret diversity gain for an interweave cognitive multiple-input multiple-output(MIMO)fading channel in the presence of an eavesdropper.Our study takes into account the ef-fects of the fading channel,the PU interference,and the eavesdropper on both spectrum sensing and data transmission phases.We demonstrate that utilizing all the antennas for sensing eliminates the limiting effects of missed detection probability and PU interference on the secret diversity gain.As a result,the cognitive user can achieve the same level of secret diversity gain as a conventional non-cognitive system(CNCS).Our an-alytical results are further validated through simula-tions. 展开更多
关键词 cognitive radio diversity gain MIMO physical layer security secrecy outage probability spectrum sensing
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STAP with adaptive calibration of array mutual coupling and gain/phase errors
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作者 Quanyang BI Dan LI Jianqiu ZHANG 《Chinese Journal of Aeronautics》 2025年第7期545-556,共12页
To address the significant degradation of Space-Time Adaptive Processing(STAP)performance when the array elements have mutual coupling and gain/phase errors,a STAP algorithm with adaptive calibration for the above two... To address the significant degradation of Space-Time Adaptive Processing(STAP)performance when the array elements have mutual coupling and gain/phase errors,a STAP algorithm with adaptive calibration for the above two array errors is proposed in this article.First,based on a defined error matrix that simultaneously considers both array mutual coupling and gain/phase errors,a STAP signal model including these errors is given.Then,utilizing the defined signal model,it is demonstrated that the estimation of the defined error matrix can be formulized as a standard convex optimization problem with the low-rank structure of the clutter covariance matrix and the subspace projection theory.Once the defined error matrix is estimated by solving the convex optimization problem,it is illustrated that a STAP method with adaptive calibration of the mutual coupling and gain/phase errors is coined.Analyses also show that the proposed adaptive calibration algorithm only needs one training sample to construct the adaptive weight vector.Therefore,it can achieve a good detection performance even with severe non-homogeneous clutter environments.Finally,the simulation experiments verify the effectiveness of the proposed algorithm and the correctness of the analytical results. 展开更多
关键词 gain/phase error Mutual coupling Subspace projection Space-time adaptive processing Adaptive calibration
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Effect of multidisciplinary nursing intervention on interdialytic weight gain and quality of life among chronic hemodialysis patients:A randomized controlled trial
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作者 Rashmimala PRADHAN Pravati TRIPATHY Debaprasad KAR 《Journal of Integrative Nursing》 2025年第1期12-20,共9页
Objectives:This study was conducted to determine the effect of multidisciplinary nursing intervention(MNI)on interdialytic weight gain(IDWG)and quality of life(QoL)among chronic hemodialysis patients.Materials and Met... Objectives:This study was conducted to determine the effect of multidisciplinary nursing intervention(MNI)on interdialytic weight gain(IDWG)and quality of life(QoL)among chronic hemodialysis patients.Materials and Methods:Quantitative research approach with randomized-controlled,single-blind trial was conducted among 120 chronic hemodialysis patients in Institute of Medical Sciences and SUM Hospital Bhubaneswar,Odisha,India from February 2023 to February 2024.Participants were randomly assigned into the experimental group(n1=65)and control group(n2=55)by block randomization methods.The experimental group received the intervention phase up to the 6th week,along with the usual treatment,and the control group received only standard treatment up to the end of the study.After that,they received the diet chart plan and fluid distribution timetable.Results:Significant improvements were found in IDWG and QoL for the experimental group.The experimental group exhibited a sharp decline in weight gain within the group(F=20.05,P<0.001)between the group(F=13.02,P<0.001),interaction effects between the groups across the time point(F=5.67,P<0.005).Kidney disease QoL scores(KDQOL^(TM)36)increased from 49.38±9.56 to 58.63±6.04 in the experimental group,compared to an increase from 50.84±9.25 to 52.04±8.02 in the control group.Conclusion:This trial showed that MNIs significantly reduced IDWG and improved KDQOL^(TM)36 scores,with the experimental group outperforming the control,highlighting the intervention’s effectiveness. 展开更多
关键词 Hemodialysis patients interdialytic weight gain multidisciplinary nursing intervention quality of life randomized controlled trials
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Fishing Ship Trajectory Tracking Control Based on the Closed-Loop Gain Shaping Algorithm Under Rough Sea
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作者 SONG Chun-yu GUO Te-er SUI Jiang-hua 《China Ocean Engineering》 2025年第2期365-372,共8页
This paper proposes a separated trajectory tracking controller for fishing ships at sea state level 6 to solve the trajectory tracking problem of a fishing ship in a 6-level sea state,and to adapt to different working... This paper proposes a separated trajectory tracking controller for fishing ships at sea state level 6 to solve the trajectory tracking problem of a fishing ship in a 6-level sea state,and to adapt to different working environments and safety requirements.The nonlinear feedback method is used to improve the closed-loop gain shaping algorithm.By introducing the sine function,the problem of excessive control energy of the system can be effectively solved.Moreover,an integral separation design is used to solve the influence of the integral term in conventional PID controllers on the transient performance of the system.In this paper,a common 32.98 m large fiberglass reinforced plastic(FRP)trawler is adopted for simulation research at the winds scale of Beaufort No.7.The results show that the track error is smaller than 3.5 m.The method is safe,feasible,concise and effective and has popularization value in the direction of fishing ship trajectory tracking control.This method can be used to improve the level of informatization and intelligence of fishing ships. 展开更多
关键词 trajectory tracking control nonlinear feedback control fishing ship closed-loop gain shaping algorithm rough sea
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Design and implementation of automatic gain control algorithm for Ocean 4A scatterometer
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作者 LIU Yongqing LIU Peng +3 位作者 ZHAI Limin LIU Shuyi JIA Yan ZHANG Xiangkun 《Journal of Systems Engineering and Electronics》 2025年第2期344-352,共9页
The Ocean 4A scatterometer, expected to be launched in 2024, is poised to be the world’s first spaceborne microwave scatterometer utilizing a digital beamforming system. To ensure high-precision measurements and perf... The Ocean 4A scatterometer, expected to be launched in 2024, is poised to be the world’s first spaceborne microwave scatterometer utilizing a digital beamforming system. To ensure high-precision measurements and performance sta-bility across diverse environments, stringent requirements are placed on the dynamic range of its receiving system. This paper provides a detailed exposition of a field-programmable gate array (FPGA)-based automatic gain control (AGC) design for the spaceborne scatterometer. Implemented on an FPGA, the algo-rithm harnesses its parallel processing capabilities and high-speed performance to monitor the received echo signals in real time. Employing an adaptive AGC algorithm, the system gene-rates gain control codes applicable to the intermediate fre-quency variable attenuator, enabling rapid and stable adjust-ment of signal amplitudes from the intermediate frequency amplifier to an optimal range. By adopting a purely digital pro-cessing approach, experimental results demonstrate that the AGC algorithm exhibits several advantages, including fast con-vergence, strong flexibility, high precision, and outstanding sta-bility. This innovative design lays a solid foundation for the high-precision measurements of the Ocean 4A scatterometer, with potential implications for the future of spaceborne microwave scatterometers. 展开更多
关键词 spaceborne scatterometer automatic gain control(AGC) field-programmable gate array(FPGA) signal acquisition.
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Compact,gain-enhanced 5G mmWave antenna with metallic ground-backed reflector for high-speed railway communication systems
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作者 Dunya Zeki Mohammed Ahmed J.A.Al-Gburi 《High-Speed Railway》 2025年第4期281-292,共12页
This research presents a compact,high-gain millimeter-wave antenna tailored for reliable 5 G communication in high-speed railway environments.The proposed antenna supports dual-band operation at 28 GHz(n257/n258)and 3... This research presents a compact,high-gain millimeter-wave antenna tailored for reliable 5 G communication in high-speed railway environments.The proposed antenna supports dual-band operation at 28 GHz(n257/n258)and 38 GHz(n260),enabling robust Vehicle-to-Infrastructure(V2I)links required for next-generation railway systems.The radiator occupies only 12 mm×8mm on a Rogers 6010LM substrate(ε_(r)=10.2,h=0.64 mm).A Metallic Ground-Backing(MGB)reflector,positioned 9mm behind the patch—λ/4 at 28 GHz—enhances forward radiation,suppresses back-lobes,and ensures highly directional coverage along railway tracks.The antenna achieves measured peak gains of 7.96 dBi at 28 GHz and 8.20 dBi at 38 GHz,with excellent impedance matching and stable radiation patterns under mobility scenarios.Its unique combination of compact footprint,reflectoraided gain enhancement,and stable dual-band performance under dynamic conditions distinguishes it from conventional millimeter-wave solutions,making it a strong candidate for 5G-based high-speed railway communication modules and arrays. 展开更多
关键词 Millimeter-wave antenna Metallic ground backing reflector gain enhanced 28/38 GHz COMPACT High-speed railway
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经验获益还是时间损失?老化心态对时尚消费的影响机制
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作者 王静 王雪华 范秀成 《心理学报》 北大核心 2026年第1期151-165,I0012-I0016,共20页
人口老龄化已成为全球性现象,积极应对老龄化的有效举措之一是大力发展银发经济。为充分释放老年人口消费潜力,需洞察不同老化心态对老年消费行为的影响。本研究通过1个调查和4个实验,检验了老年人看待过去时“经验获益”(vs.“时间损失... 人口老龄化已成为全球性现象,积极应对老龄化的有效举措之一是大力发展银发经济。为充分释放老年人口消费潜力,需洞察不同老化心态对老年消费行为的影响。本研究通过1个调查和4个实验,检验了老年人看待过去时“经验获益”(vs.“时间损失”)心态对时尚消费的作用机制和边界条件。研究表明:相比“时间损失”心态,“经验获益”心态将提升时尚消费意愿,老化威胁感知在老化心态与时尚消费的关系中起中介作用。同时,死亡凸显调节不同老化心态对时尚消费的影响。低死亡凸显情况下,持“经验获益”(vs.“时间损失”)老化心态的个体更偏好时尚消费;而高死亡凸显情况下,两者之间差异消失。本文从“经验获益”与“时间损失”视角,剖析老化心态及其对时尚消费的作用,丰富了老年消费、时尚消费和年老身份建构方面的文献。 展开更多
关键词 老化心态 时尚消费 老化威胁感知 时间损失 经验获益
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红松一代种子园半同胞子代遗传变异与优良家系选择
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作者 陆斐 刘刚 +7 位作者 吕伟伟 王丽丽 吕重阳 赵溪月 裴乙达 杨淳博 罗见 刘克俭 《东北林业大学学报》 北大核心 2026年第2期9-17,共9页
为了选择优良家系及单株,以吉林省永吉县红松(Pinus koraiensis)一代种子园自由授粉子代,20 a林龄45个半同胞家系为材料,通过测定树高、胸径、单株材积等生长性状,进行方差分析、遗传变异分析,估算各性状遗传参数和育种值。结果表明:家... 为了选择优良家系及单株,以吉林省永吉县红松(Pinus koraiensis)一代种子园自由授粉子代,20 a林龄45个半同胞家系为材料,通过测定树高、胸径、单株材积等生长性状,进行方差分析、遗传变异分析,估算各性状遗传参数和育种值。结果表明:家系间树高、胸径和单株材积均存在极显著差异(P<0.01),参试家系生长性状呈现丰富的遗传变异,家系间表型变异系数范围为14.33%~52.08%,遗传变异系数范围为6.85%~27.23%,单株材积的表型变异系数和遗传变异系数最大(分别为48.31%、17.69%),其中单株材积的家系遗传力高达0.517,显著高于树高(0.461)和胸径(0.447),表明其具有更高的遗传改良潜力。生长性状间呈显著正相关,胸径与单株材积的相关性最高(r=0.959)。通过最佳线性无偏预测(BLUP)法估算目标性状育种值,并结合邓肯(Duncan)多重比较法分析性状表型差异显著性,筛选出9个优良家系,目标性状遗传增益显著,其中树高、胸径、单株材积遗传增益分别为9.17%、16.96%、42.96%。采用性状综合评价法在优良家系内选择70株优良单株,其树高、胸径、单株材积平均遗传增益分别为7.02%、15.47%、38.18%。 展开更多
关键词 红松 半同胞子代 遗传变异 育种值 优良家系 优良单株 遗传增益
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人才流失,还是人才获得?:人口迁移对迁出地教育人力资本积累的影响及其机制
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作者 任远 张简妮 《人口与经济》 北大核心 2026年第1期74-90,共17页
我国正在经历着超大规模的人口迁移流动,加剧了区域人口增减分化,使地区发展面临诸多挑战。利用人口普查和人口抽样调查的微观数据,研究分析我国人口迁移流动过程中的“人才流失”和“人才获得”现象,分析人口迁移对迁出地教育人力资本... 我国正在经历着超大规模的人口迁移流动,加剧了区域人口增减分化,使地区发展面临诸多挑战。利用人口普查和人口抽样调查的微观数据,研究分析我国人口迁移流动过程中的“人才流失”和“人才获得”现象,分析人口迁移对迁出地教育人力资本积累的影响及其机制。迁出的人口具有相对较高的受教育程度,对迁出地来说,人口迁出表现出劳动力资源和人才的流失,但是迁移对于迁出地教育人力资本积累的总体作用仍然是积极的。实证研究表明,我国人口迁移流动对迁出地而言是一种“人才流失”,更客观具有“人才获得”的作用。人才的迁出相较于普通劳动力的迁出,对于地区人力资本积累的促进作用表现得更加明显。基于迁移前景的激励作用、迁移者家庭汇款的收入效应,会提高家庭教育投资的意愿和能力;人口迁出地政府为了应对人口外迁和人力资本流失所进行的补偿性教育投资,会使得迁出地的教育人力资本在人口迁出的过程中呈现增长。研究对如何扩大“人才获得”效应、推动迁移过程中的迁出地教育人力资本积累和地方发展,以及对促进实现区域平衡协调发展提出建议。 展开更多
关键词 人才流失 人才获得 教育人力资本 教育投资 人口迁移
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公众获得感何以影响政治认同——基于制度化政治参与和政治价值观的分析
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作者 郑建君 吴润琏 《吉林大学社会科学学报》 北大核心 2026年第1期48-58,267,共12页
民心是最大的政治,民心向背是人民群众对政治系统认同状况的直接体现。作为公众美好生活感知的重要组成部分,获得感对政治认同具有重要的预测作用,而现有研究对二者之间作用机制的关注相对缺乏。文章基于认知-情感系统理论构建了一个有... 民心是最大的政治,民心向背是人民群众对政治系统认同状况的直接体现。作为公众美好生活感知的重要组成部分,获得感对政治认同具有重要的预测作用,而现有研究对二者之间作用机制的关注相对缺乏。文章基于认知-情感系统理论构建了一个有调节的中介模型,以探讨公众获得感对政治认同的影响机制及作用条件。采用问卷调查方法从全国31个省(自治区、直辖市)获得有效数据11000份,假设检验结果显示:在公众获得感对政治认同的正向影响中,制度化政治参与发挥部分中介作用;同时,政治价值观对制度化政治参与在公众获得感与政治认同关系间的中介效应具有正向调节作用,即在公众获得感与政治认同的关系中,个体济世兴邦政治价值观水平越高,制度化政治参与的中介作用越强。研究发现加深了对公众获得感影响政治认同的机制及作用条件的认识和理解,为全面提升人民群众获得感、激发制度化政治参与、加强政治认同建设等提供了有益的实证支持与实践启示。 展开更多
关键词 获得感 政治认同 制度化政治参与 政治价值观 被调节的中介模型
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单开关耦合电感倍压型组合拓扑变换器
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作者 荣德生 邢雪 孙瑄瑨 《电力系统及其自动化学报》 北大核心 2026年第1期42-50,共9页
为解决直流变换器在高压应用场景中增益不足与效率受限的瓶颈问题,基于耦合电感倍压技术提出一种新型组合拓扑结构的DC/DC变换器。该方案融合Boost与Sepic电路结构优势,引入耦合电感倍压单元及无源钳位网络构建电流输入型架构,在保证输... 为解决直流变换器在高压应用场景中增益不足与效率受限的瓶颈问题,基于耦合电感倍压技术提出一种新型组合拓扑结构的DC/DC变换器。该方案融合Boost与Sepic电路结构优势,引入耦合电感倍压单元及无源钳位网络构建电流输入型架构,在保证输入电流连续的情况下还可实现漏感能量回收与全开关器件零电流开通。对变换器工作原理进行了详细分析,并提供了其在连续模式下的性能参数及临界条件。结果表明,新拓扑具备高电压增益与低电压应力优势。此外,实验搭建200 W原理样机,验证了变换器的高效运行特性,并有效支撑了理论分析的准确性。 展开更多
关键词 耦合电感 高增益 电流输入型 无源钳位 零电流开关
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基于人工磁导体结构的一维5G毫米波宽角扫描阵列天线
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作者 马战刚 张卿 +1 位作者 冯思润 赵鲁豫 《电子与信息学报》 北大核心 2026年第2期784-793,共10页
随着5G毫米波技术的快速发展,对天线的高增益、宽波束覆盖和小尺寸提出了更高要求。该文基于人工磁导体(AMC)结构,设计了一种毫米波频段的具有大角域扫描能力的单极化一维阵列天线。通过利用AMC结构的同相反射特性,天线阵列在提升带宽... 随着5G毫米波技术的快速发展,对天线的高增益、宽波束覆盖和小尺寸提出了更高要求。该文基于人工磁导体(AMC)结构,设计了一种毫米波频段的具有大角域扫描能力的单极化一维阵列天线。通过利用AMC结构的同相反射特性,天线阵列在提升带宽和增益的同时,实现了显著的宽角扫描能力。天线单元采用单极化设计,通过堆叠式结构优化电流分布,改善了带宽和端口隔离度。阵列以4.6 mm(26 GHz时的0.4波长)间距组阵,加载AMC结构后,阵中天线单元的增益提升至5 dBi,且相邻单元的方形贴片参与辐射,进一步展宽了辐射方向图。仿真结果表明,天线阵列覆盖23.7~28 GHz频段,最大增益达13.8 dBi,在26 GHz时实现了±80°的宽角扫描性能。此外,加工测试验证了设计的可行性,实测结果与仿真吻合良好,隔离度优于-15 dB。该文的创新点在于通过AMC结构优化天线单元的辐射特性,结合独特的阵列设计,实现了宽频带、高增益和宽角扫描的平衡,为5G毫米波终端天线的设计提供了新的思路。 展开更多
关键词 5G毫米波 AMC结构 宽角扫描 高增益 阵列天线
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一种高增益软开关准Z源DC-DC变换器
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作者 张涛 白文龙 +3 位作者 张丽 韩庆林 李云飞 张亚飞 《太阳能学报》 北大核心 2026年第2期8-17,共10页
针对传统准Z源DC-DC变换器存在电压增益低和器件电压应力高的问题,提出一种高增益软开关准Z源DC-DC变换器(HGSS-QZS)。通过三绕组耦合电感匝比和开关管占空比共同调节,可提高升压能力和增益调节的自由度;并利用钳位电路吸收耦合电感的... 针对传统准Z源DC-DC变换器存在电压增益低和器件电压应力高的问题,提出一种高增益软开关准Z源DC-DC变换器(HGSS-QZS)。通过三绕组耦合电感匝比和开关管占空比共同调节,可提高升压能力和增益调节的自由度;并利用钳位电路吸收耦合电感的漏感能量,降低漏感引起的电压尖峰。首先详细分析HGSS-QZS变换器的工作原理,推导出电压增益、器件电压电流应力和效率损耗,其次进行参数设计并与现有变换器对比。表明HGSS-QZS变换器具有电压增益高、器件电压应力低、软开关和效率高的优点。最后搭建200 W实验样机,结合仿真与实验对比验证了HGSS-QZS变换器的有效性和可行性。 展开更多
关键词 DC-DC变换器 准Z源 高增益 光伏发电 软开关 耦合电路 三绕组
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面向机械通气的自适应增益与负压辅助协同控制方法研究
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作者 石岩 刘卉 +2 位作者 杜晓辉 郁红漪 赵朝义 《液压气动与密封》 2026年第3期1-7,共7页
针对机械通气精确控制难题,构建正负压统一框架,提出自适应增益-负压协同控制方法。该策略依据流量与肺弹性自适应调整增益,并将负压作为负载进行前馈补偿。仿真数据表明,相比固定PI控制导致的8~9 L/min尖峰流量振荡,该方法能将吸气流... 针对机械通气精确控制难题,构建正负压统一框架,提出自适应增益-负压协同控制方法。该策略依据流量与肺弹性自适应调整增益,并将负压作为负载进行前馈补偿。仿真数据表明,相比固定PI控制导致的8~9 L/min尖峰流量振荡,该方法能将吸气流量峰值稳定在6~8 L/min,且波形平滑。结果证实,该方法在不同工况下可显著降低压力误差,在保证潮气量前提下减小驱动压,为航空及医疗呼吸支持提供了智能控制路径。 展开更多
关键词 机械通气 负压辅助通气 自适应增益控制 肺力学模型 压力控制
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员工下行时间比较对工作获得感的影响机制
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作者 许科 金瑶 赵国祥 《心理研究》 2026年第1期68-76,共9页
员工工作中的“获得”感受并非来源于绝对收益,而是将自己的收益与投入相权衡,将自身与参照物相对比后产生的体验。本研究基于资源保存理论,发放了397份三个时间点的问卷,揭示了下行时间比较对员工工作获得感的影响机制。结果表明:(1)... 员工工作中的“获得”感受并非来源于绝对收益,而是将自己的收益与投入相权衡,将自身与参照物相对比后产生的体验。本研究基于资源保存理论,发放了397份三个时间点的问卷,揭示了下行时间比较对员工工作获得感的影响机制。结果表明:(1)下行时间比较对工作获得感有显著正向影响;(2)工作重塑在下行时间比较与工作获得感之间起部分中介作用;(3)社会比较作为重要的边界条件,负向调节了直接路径与中介模型。本研究构建并验证了“社会比较优先,时间比较补位”的动态心理资源调适模型,深化了学界对时间比较和社会比较关系的理解,同时也从实证层面阐明了工作获得感的双路径实现机制,既依赖于认知层面的“内观内省”,也可通过行为层面的“重塑之行”最终达成。 展开更多
关键词 下行时间比较 工作获得感 工作重塑 社会比较
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