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A pilot randomized controlled trial of KangminⅠdecoction as a treatment for atopic eczema
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作者 MA Tian XIAO Qingqing +11 位作者 FEI Xiaoya ZHAO Huaibo LIU Liu CHAI Yuanyuan SUN Xiaoying WANG Yifei XU Rong CHEN Jie ZHOU Mi QIN Wanzhang LI Bin LI Xin 《World Journal of Integrated Traditional and Western Medicine》 2025年第1期10-18,共9页
Background:Atopic eczema is the most common type of skin disorder in both children and adults.It is characterized by erythema,pruritus,papules,xeransis,and lichenification.The KangminⅠdecoction,a Chinese herbal medic... Background:Atopic eczema is the most common type of skin disorder in both children and adults.It is characterized by erythema,pruritus,papules,xeransis,and lichenification.The KangminⅠdecoction,a Chinese herbal medicine prepared with several ingredients and used to treat eczema,was formulated according to traditional Chinese medicine theory.Objectives:To investigate the efficacy and safety of KangminⅠdecoction for treating atopic eczema compared to that of loratadine.Methods:90 patients were enrolled at the Yueyang Hospital of Integrated Traditional Chinese and Western Medicine and randomly divided into the KangminⅠdecoction treatment group(n=45)and loratadine control group(n=45).Clinical efficacy was evaluated using the Eczema Area and Severity Index(EASI),Dermatology Life Quality Index(DLQI),adverse events(AEs),and recurrence rates,which were compared between the groups.Results:Compared to the loratadine control group(51.16%,18.60%),the KangminⅠdecoction group(7.72%,4.55%)displayed a significantly reduced effective rate(x^(2)=8.324,P=0.040)and recurrence rate(x^(2)=4.225,P=0.040).The incidence of AEs was similar between the groups(P=0.502).Conclusions:These results support further development of KangminⅠdecoction for the treatment of eczema.The KangminⅠdecoction showed good efficacy with a low recurrence rate and tolerable AEs.The main limitations of this study include the small sample size and the short treatment and follow-up periods.Larger controlled studies are needed to more adequately evaluate both safety and efficacy. 展开更多
关键词 Atopic eczema The KangminⅠdecoction pilot randomized controlled trial
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Effect of acupressure on postpartum low back pain, salivary cortisol, physical limitations, and depression: a randomized controlled pilot study 被引量:9
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作者 Cheng Hsuesh-Yu Carol Shieh +1 位作者 Wu Bei-Yu Cheng Yu-Fen 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2020年第1期128-136,共9页
OBJECTIVE:To investigate the effect of acupressure on postpartum low back pain(LBP),salivary cortisol,physical limitations,and postpartum depression.METHODS:Participants were 70 postpartum women who were randomly assi... OBJECTIVE:To investigate the effect of acupressure on postpartum low back pain(LBP),salivary cortisol,physical limitations,and postpartum depression.METHODS:Participants were 70 postpartum women who were randomly assigned to either an intervention(n=35)or a control(n=35)group.The intervention group received 10 acupressure sessions(1 session per day,5 d per week).The control group received 10 sham acupressure sessions.Outcomes were assessed using a visual analogue scale(LBP intensity),salivary cortisol values(LBP biomarker),and Chinese versions of the Roland-Morris Disability Questionnaire(daily activity limitations),Oswes-try Disability Index(physical activity limitations),and the Edinburgh Postnatal Depression Scale(postpartum depression).RESULTS:Participants in the intervention group had significantly lower levels of LBP intensity,daily activity limitations,physical activity limitations,and postpartum depression than those in the control group.There was no significant between-group difference in salivary cortisol.CONCLUSION:Acupressure may reduce postpartum LBP intensity and limitations in daily and physical activity,and alleviate postpartum depressive symptoms.Acupressure should be offered in postpartum care settings as an alternative treatment for postpartum women with LBP. 展开更多
关键词 ACUPRESSURE Low back pain POSTPARTUM period DEPRESSION RANDOMIZED controlLED TRIAL pilot projects
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Investigation into the Independent Metering Control Performance of a Twin Spools Valve with Switching Technology-controlled Pilot Stage 被引量:8
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作者 Qi Zhong Huiming Bao +3 位作者 Yanbiao Li Haocen Hong Bin Zhang Huayong Yang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2021年第5期226-242,共17页
In hydraulic area,independent metering control(IMC)technology is an effective approach to improve system efficiency and control flexibility.In addition,digital hydraulic technology(DHT)has been verified as a reasonabl... In hydraulic area,independent metering control(IMC)technology is an effective approach to improve system efficiency and control flexibility.In addition,digital hydraulic technology(DHT)has been verified as a reasonable method to optimize system dynamic performance.Integrating these two technologies into one component can combine their advantages together.However,few works focused on it.In this paper,a twin spools valve with switching technologycontrolled pilot stage(TSVSP)is presented,which applied DHT into its pilot stage while appending IMC into its main stage.Based on this prototype valve,a series of numerical and experiment analysis of its IMC performance with both simulated load and excavator boom cylinder are carried out.Results showed fast and robust performance of pressure and flow compound control with acceptable fluctuation phenomenon caused by switching technology.Rising time of flow response in excavator cylinder can be controlled within 200 ms,meanwhile,the recovery time of rod chamber pressure under suddenly changed condition is optimized within 250 ms.IMC system based on TSVSP can improve both dynamic performance and robust characteristics of the target actuator so it is practical in valve-cylinder system and can be applied in mobile machineries. 展开更多
关键词 High speed on/off valve(HSV) Digital hydraulic technology(DHT) Switching pilot control Twin spools valve Independent metering control(IMC)
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Supported Rehabilitation for Individuals Who Have Experienced a Stroke: A Pilot Control Trial
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作者 Charlotte Gaynor Laura Devaux +3 位作者 Morley Stephanie Kate Petropoulou Brendon Stubbs Andrew Soundy 《Open Journal of Therapy and Rehabilitation》 2016年第2期87-98,共12页
The purpose of this study was to pilot an innovative and supported intervention for individuals with a stroke. A pilot control trial with qualitative interviews was undertaken within a university- community setting. T... The purpose of this study was to pilot an innovative and supported intervention for individuals with a stroke. A pilot control trial with qualitative interviews was undertaken within a university- community setting. Thirteen individuals who had experienced a stroke for periods of least 6 months (6 male, average 71 years) were assigned to the intervention group and 7 individuals (2 male, average age 67.9 years) assigned to the control group. Eight individuals from the intervention group completed a single interview. The procedures that related to recruitment and retention and data collection methods were considered. Outcome measures including;self-efficacy, falls self-efficacy and group membership, for both groups were taken at baseline, 11 weeks, 22 weeks. There was an additional assessment at 52 weeks for the intervention group. The structured interview was designed to focus on experiences of the intervention. Self-efficacy remained stable across time for both groups. An improvement in falls self-efficacy was noted in the intervention group at 11 weeks. Consistent improvement (from baseline) was observed in the identity scale across the 52 weeks. Qualitative data provided additional findings related to identity and confidence. Details considering recruitment and retention are also provided. This pilot study provided data that can be used for a further full-scale trial to be considered. 展开更多
关键词 STROKE pilot controlled Trial EXERCISE REHABILITATION
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浅析奥维互动地图3D视角和DJI Pilot飞控软件在森林资源调查监测中的应用技术
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作者 覃道彪 《内蒙古林业调查设计》 2025年第2期58-60,75,共4页
随着科技的不断进步,森林资源调查监测领域正经历着一场技术革命。文章探析使用奥维互动地图制作调查图层底图,结合大疆无人机和DJI Pilot飞控软件进行无人机航点规划与飞行控制,实现森林资源的高效、精准调查和监测,具体流程包括调查... 随着科技的不断进步,森林资源调查监测领域正经历着一场技术革命。文章探析使用奥维互动地图制作调查图层底图,结合大疆无人机和DJI Pilot飞控软件进行无人机航点规划与飞行控制,实现森林资源的高效、精准调查和监测,具体流程包括调查图层底图的制作、无人机航点的规划与导入、利用奥维互动地图3D视角进行作业区域的三维可视化,以及运用手控无人机进行航点飞拍,以期提高数据采集的速度和质量、增强森林资源的实时监控能力。 展开更多
关键词 森林资源调查监测 奥维互动地图 DJI pilot飞控软件 大疆无人机
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基于分段曲线补偿的先导手柄非线性误差优化方法
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作者 田保珍 原晋阳 权鹏程 《起重运输机械》 2026年第2期22-27,共6页
在挖掘机的工作体系中,先导手柄作为人与挖掘机进行交互的直接部件,其操控精度对人机协同作业效率具有重要影响。为提升挖掘机手柄操控的精准性,文中针对手柄在转动过程中产生的非线性误差问题开展系统性误差补偿机制探索。首先对先导... 在挖掘机的工作体系中,先导手柄作为人与挖掘机进行交互的直接部件,其操控精度对人机协同作业效率具有重要影响。为提升挖掘机手柄操控的精准性,文中针对手柄在转动过程中产生的非线性误差问题开展系统性误差补偿机制探索。首先对先导手柄在转动时产生的误差数据进行科学划分;其次使用Matlab结合最小二乘法与样条插值法求解各误差区间对应的补偿曲线方程,建立非线性误差的补偿模型;在SolidWorks中进行三维建模,并通过ADAMS动力学仿真平台对所提补偿方案进行动态性能验证。仿真结果表明:分段曲线补偿方法能有效提升先导手柄转动时操纵角与触头位移的线性关系,显著降低了非线性误差,从而验证了该补偿方法的可行性,为提升手柄操控精准性提供了技术支持。 展开更多
关键词 先导手柄 压盘 操纵角 误差补偿 模型 优化方法
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Prediction of pilot workload in helicopter landing after one engine failure 被引量:4
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作者 Zhiming YU Xufei YAN Renliang CHEN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2020年第12期3112-3124,共13页
This paper presents a method to predict the pilot workload in helicopter landing after one engine failure.The landing procedure is simulated numerically via applying nonlinear optimal control method in the form of per... This paper presents a method to predict the pilot workload in helicopter landing after one engine failure.The landing procedure is simulated numerically via applying nonlinear optimal control method in the form of performance index,path constraints and boundary conditions based on an augmented six-degree-of-freedom rigid-body flight dynamics model,solved by collocation and numerical optimization method.UH-60 A helicopter is taken as the sample for the demonstration of landing after one engine failure.The numerical simulation was conducted to find the trajectory of helicopter and the controls from pilot for landing after one engine failure with different performance index considering the factor of pilot workload.The reasonable performance index and corresponding landing trajectory and controls are obtained by making a comparison with those from the flight test data.Furthermore,the pilot workload is evaluated based on wavelet transform analysis of the pilot control activities.The workloads of pilot control activities for collective control,longitudinal and lateral cyclic controls and pedal control during the helicopter landing after one engine failure are examined and compared with those of flight test.The results show that when the performance index considers the factor of pilot workload properly,the characteristics of amplitudes and constituent frequencies of pilot control inputs in the optimal solution are consistent with those of the pilot control inputs in the flight test.Therefore,the proposed method provides a tool of predicting the pilot workload in helicopter landing after one engine failure. 展开更多
关键词 Engine failure Nonlinear optimal control method pilot control activity pilot workload Wavelet transform analysis
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Augmented flight dynamics model for pilot workload evaluation in tilt-rotor aircraft optimal landing procedure after one engine failure 被引量:11
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作者 Xufei YAN Renliang CHEN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第1期92-103,共12页
An augmented flight dynamics model is developed to extend the existing flight dynamics model of tilt-rotor aircraft for optimal landing procedure analysis in the event of one engine failure.Compared with the existing ... An augmented flight dynamics model is developed to extend the existing flight dynamics model of tilt-rotor aircraft for optimal landing procedure analysis in the event of one engine failure.Compared with the existing flight dynamics model, the augmented model involves with more pilot control information in cockpit and is validated against the flight test data. Based on the augmented flight dynamics model, the optimal landing procedure of XV-15 tilt-rotor aircraft after one engine failure is formulated into a Nonlinear Optimal Control Problem(NOCP), solved by collocation and numerical optimization method. The time histories of pilot controls in cockpit during the optimal landing procedure are obtained for the evaluation of pilot workload. An evaluation method which can synthetically quantify the pilot workload in time and frequency domains is proposed with metrics of aggressiveness and cutoff frequencies of pilot controls. The scale of the pilot workload is compared with those of the shipboard landing procedures, bob-up/bob-down and dash/quickstop maneuvers of UH-60 helicopter. The results show that the aggressiveness of pilot collective and longitudinal controls for the tilt-rotor aircraft optimal landing procedure after one engine failure are higher than those for UH-60 helicopter shipboard landing procedures up to the condition of sea state 4, while the pilot cutoff frequency of collective control is lower than that of the bob-up/bob-down maneuver but the pilot cutoff frequency of longitudinal control is higher than that of the dash/quick-stop maneuver. The evaluated pilot workload level is between Cooper–Harper HQR Level 2 and Level 3. 展开更多
关键词 LANDING PROCEDURE ONE engine failure OPTIMAL control problem pilot WORKLOAD Tilt-rotor aircraft
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新疆硫磺沟煤田火烧区地热双水平井施工技术
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作者 赵俊杰 吴纪修 +2 位作者 李宽 张恒春 曹龙龙 《钻探工程》 2026年第1期134-140,共7页
本研究以新疆煤田火灾治理为背景,借鉴国外Eavor‐Loop等闭式地热系统(CLGS)工程经验,旨在通过提取地下热能使煤田火烧区降温,以恢复火烧区煤炭资源开采,并实现地下热能利用的双重目标。采用闭式双水平井取热方案,设计了“稳斜+造斜+水... 本研究以新疆煤田火灾治理为背景,借鉴国外Eavor‐Loop等闭式地热系统(CLGS)工程经验,旨在通过提取地下热能使煤田火烧区降温,以恢复火烧区煤炭资源开采,并实现地下热能利用的双重目标。采用闭式双水平井取热方案,设计了“稳斜+造斜+水平+造斜+稳斜”的五段制井眼轨道双水平井轨迹。针对煤田火烧区高温破碎地层特性,创新采用“小口径先导孔+大口径回拖扩孔”工艺完成施工,提出了适用于新疆硫磺沟煤田火烧区高温岩层的高效、低成本钻探和换热取热技术方案。针对施工中遇到的井下高温(>170℃)、地层不稳定和全井段大井斜等挑战,采取多种钻完井工艺方法,优化钻井液体系和设备,应用耐高温测量仪器及井下动力钻具,解决了钻遇煤田火区时地层松散破碎、失返漏失、异常高温等问题。为未来煤田火区钻完井施工形成可推广的技术范式。 展开更多
关键词 煤田火烧区 地热井 双水平井 导向孔钻进 回拖扩孔 煤田火灾治理
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大数据治理提升了公共服务满意度吗?——基于国家级大数据综合试验区的合成控制法检验
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作者 唐慧 崔冠云 《四川行政学院学报》 2026年第1期37-50,103,共15页
数字时代到来催生了大数据治理的广泛实践,各级政府将大数据治理的政策创新视为提升公共服务的重要抓手。然而,这些政策创新的实际效果如何,是否真正实现了技术赋能治理的预期目标,仍需进一步检验。文章以国家级大数据综合试验区的设立... 数字时代到来催生了大数据治理的广泛实践,各级政府将大数据治理的政策创新视为提升公共服务的重要抓手。然而,这些政策创新的实际效果如何,是否真正实现了技术赋能治理的预期目标,仍需进一步检验。文章以国家级大数据综合试验区的设立这一政策试点为例,借助合成控制法评估大数据治理对公共服务满意度的影响。结果显示,国家级大数据综合试验区的设立可以显著提升公共服务满意度,但呈现出显著的时空异质性特征。一方面,在空间维度上,西部地区城市呈现“先抑后扬”的改善趋势,而东部地区城市表现为短期提升后持续回落。另一方面,在时间维度上,政策效果呈现动态演变特征,反映了技术治理成效的阶段性特点。研究表明,单纯的技术供给无法自动转化为治理效能,其积极作用的发挥需要辅以制度弹性和以公众为中心的价值取向。通过差异化的政策工具箱设计、需求侧治理机制创新等方式,推动大数据治理从“技术驱动”向“价值驱动”转型,切实提升公共服务满意度。 展开更多
关键词 大数据治理 公共服务满意度 国家级大数据综合试验区 合成控制法
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Testing the feasibility and effects of a self-management support intervention for patients with cancer and their family caregivers to reduce pain and related symptoms (ANtiPain): Study protocol of a pilot study
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作者 Antje Koller Monika Hasemann +2 位作者 Karin Jaroslawski Sabina De Geest Gerhild Becker 《Open Journal of Nursing》 2014年第2期85-94,共10页
Despite effective treatment options, more than 40% of cancer patients receive inadequate pain management. Our previous pilot study resulted in substantial adaptations of a cancer pain self-management intervention, the... Despite effective treatment options, more than 40% of cancer patients receive inadequate pain management. Our previous pilot study resulted in substantial adaptations of a cancer pain self-management intervention, the German PRO-Self? Plus Pain Control Program originally developed in the United States. This program will be implemented into clinical practice at the Medical Center-University of Freiburg. The purpose of this multiple methods pilot study is to test the implementation regarding feasibility and effects in clinical practice. In a randomized, wait-list controlled pilot study, adult oncology in-patients of a palliative care consultation service with pain >3/10 will be recruited. The intervention will be performed by a specialized advanced practice nurse with an in-hospital visit and, after discharge, via phone calls and visits. The follow-up will be personalized according to a clinical algorithm that factors in pain intensity, satisfaction with pain management, and patient adherence. The intervention includes structured and tailored components and is based on three key strategies: information, skill building and nurse coaching. The specific aims of this study are threefold: 1) to test the feasibility of the study and intervention procedures;2) to establish effect sizes of main outcome variables (e.g. decrease pain intensity, reduce the number of patients with pain as main symptom) for subsequent power calculation;3) to explore participants’ experiences with pain self-management support and their view of burden and benefit from study participation in a qualitative substudy. During the study period, which includes three data collection time points (T0 before, T1 one week and T2 six weeks after discharge), data will be collected via field notes of study nurses and questionnaires of patients. The results of this pilot study will build the basis for a larger comparative effectiveness study in which long term outcomes of a cancer pain self-management intervention in clinical practice will be evaluated. 展开更多
关键词 NEOPLASMS PAIN Patient Education pilot RANDOMIZED controlled TRIAL
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新型研发机构GMP中试平台推动CGT产品孵化的天津实践
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作者 原辉 张红海 +5 位作者 陈继生 司远 吴爽 李姗姗 程涛 张英驰 《中国细胞生物学学报》 2026年第1期234-240,共7页
中试是科研成果从实验室走向规模化生产的关键环节,是跨越科技成果转化“死亡之谷”的核心桥梁。细胞产品作为“活的药物”,其生产工艺复杂、质量控制难度极高。近年来,随着细胞与基因治疗产业的快速发展,传统的小规模实验室制备已难以... 中试是科研成果从实验室走向规模化生产的关键环节,是跨越科技成果转化“死亡之谷”的核心桥梁。细胞产品作为“活的药物”,其生产工艺复杂、质量控制难度极高。近年来,随着细胞与基因治疗产业的快速发展,传统的小规模实验室制备已难以满足临床转化与产业化需求。因此,建设符合药品生产质量管理规范(GMP)要求的中试平台已刻不容缓。该文以细胞生态海河实验室GMP中试平台为例,总结在硬件建设、GMP体系建设和科研立项等方面的实践举措,为同类项目提供参考与借鉴。 展开更多
关键词 细胞与基因治疗 新型研发机构 中试平台 药品生产质量管理规范 质量保证 质量控制
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预喷耦合EGR对甲醇/柴油双燃料发动机燃烧和排放的影响
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作者 黄粉莲 朱广豪 +2 位作者 万明定 王正江 雷基林 《安全与环境学报》 北大核心 2025年第10期4018-4031,共14页
研究基于三维计算流体动力学(Computational Fluid Dynamics,CFD)仿真软件,构建了甲醇/柴油双燃料发动机的CFD模型,并耦合详细的化学反应动力学机理,探究了预喷策略耦合废气再循环(Exhaust Gas Recycle,EGR)对甲醇/柴油双燃料发动机燃... 研究基于三维计算流体动力学(Computational Fluid Dynamics,CFD)仿真软件,构建了甲醇/柴油双燃料发动机的CFD模型,并耦合详细的化学反应动力学机理,探究了预喷策略耦合废气再循环(Exhaust Gas Recycle,EGR)对甲醇/柴油双燃料发动机燃烧及排放特性的影响。结果显示:当预喷油量(Pilot Injection Quantity,PIQ)不变,预喷时刻(Pilot Injection Timing,PIT)从-10℃A提前至-20℃A时,缸压和温度峰值升高,燃烧始点、燃烧中心提前,指示热效率提升;NO_(x)排放量升高,PIT在-20℃A时达到峰值,CO排放量降低,PIT在-20℃A时最低。当PIT从-20℃A提前至-30℃A时,缸压和温度峰值降低,CA10、CA50推后,指示热效率降低;NO_(x)排放量降低,CO排放量升高。但随着PIT的提前,碳烟、碳氢化合物(Hydrocarbons,HC)、CH_(3) OH和HCHO排放量呈降低趋势。当PIT不变,随着PIQ的增加,缸压和放热率的峰值升高,且放热率演变为双峰,CA10、CA50提前,指示热效率提升;NO_(x)排放量升高,较大的PIQ可使碳烟、HC、CO、CH_(3) OH和HCHO排放量保持在较低水平。随着EGR的增加,在不同预喷策略下,缸压和放热率峰值降低,CA10、CA50提前,指示热效率降低,但指示热效率均高于原机;NO_(x)排放量降低,碳烟、HC、CO、CH_(3) OH和HCHO排放量升高。当EGR增至35%时,不同预喷策略下CO排放量均高于原机;当EGR高于15%时,HCHO排放量高于原机;当EGR增至25%时,除HCHO排放量外,其余排放量均低于原机。研究最终选取预喷策略(预喷正时为-20℃A+预喷比例为5%)并耦合EGR(25%)作为最优方案,该方案使NO_(x)、碳烟、HC、CO、CH_(3) OH排放量分别较原机下降15%、2%、20.5%、1.5%、4.3%,指示热效率较原机提高了2.27百分点。 展开更多
关键词 环境工程学 反应活性控制压燃 预喷策略 废气再循环 非常规排放
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民航飞行员和管制员的时距知觉特征
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作者 罗渝川 李洪艳 +1 位作者 金雪琪 邓雪梅 《心理技术与应用》 2025年第4期246-253,共8页
采用时间二分任务,考察飞行员、管制员、普通人三组职业人群(每组各70名男性)在7个刺激时距(300ms、450ms、600ms、750ms、900ms、1050ms、1200ms)的时距知觉。结果发现,在750ms、900ms、1050ms、1200ms的时距判断上,飞行员的长反应比... 采用时间二分任务,考察飞行员、管制员、普通人三组职业人群(每组各70名男性)在7个刺激时距(300ms、450ms、600ms、750ms、900ms、1050ms、1200ms)的时距知觉。结果发现,在750ms、900ms、1050ms、1200ms的时距判断上,飞行员的长反应比例均显著高于管制员和普通人。而且,在1200ms的时距知觉判断上,管制员的长反应比例显著高于普通人。另外,飞行员的主观相等点显著低于普通人。此外,飞行员的韦伯比例显著低于管制员和普通人。可见,相较于管制员和普通人群,飞行员倾向于高估长时距的时间,其时间敏感性更强。相较于普通人群,管制员更倾向于高估长时距。研究结果有助于初步了解民航飞行员和管制员的时距知觉特征,为以后开展保障飞行安全训练提供理论支持。 展开更多
关键词 时距知觉 飞行员 管制员 民航
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基于领航一致性控制的5G时间敏感网络车车通信时间同步方法 被引量:1
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作者 陈永 张娜 +1 位作者 陶瑄 张冰旺 《铁道学报》 北大核心 2025年第5期68-76,共9页
在高速铁路下一代5G时间敏感网络(5G-TSN)下实现车车通信时间同步,对于保障高速列车行车安全至关重要。针对现有车车时间同步方法未考虑链路传输延时抖动、数据丢包等因素,导致车车通信时间同步主从时钟偏移估计不准确、稳定性差等问题... 在高速铁路下一代5G时间敏感网络(5G-TSN)下实现车车通信时间同步,对于保障高速列车行车安全至关重要。针对现有车车时间同步方法未考虑链路传输延时抖动、数据丢包等因素,导致车车通信时间同步主从时钟偏移估计不准确、稳定性差等问题,提出一种基于领航一致性控制的5G-TSN车车通信时间同步方法。建立5G-TSN下基于领航追随多智能体理论的车车通信时间同步模型;设计车车通信时间同步一致性控制协议,通过追随列车时钟状态误差动态调整,完成5G-TSN下车车通信的同步误差补偿,能够有效实现车车通信时间同步。试验结果表明,与事件触发控制和卡尔曼滤波同步比较方法相比,所提方法具有更好的稳定性和同步性能。 展开更多
关键词 时间同步 5G时间敏感网络 车车通信 领航追随 一致性控制
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Temporal Prediction of Aircraft Loss-of-Control: A Dynamic Optimization Approach
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作者 Chaitanya Poolla Abraham K. Ishihara 《Intelligent Control and Automation》 2015年第4期241-248,共8页
Loss of Control (LOC) is the primary factor responsible for the majority of fatal air accidents during past decade. LOC is characterized by the pilot’s inability to control the aircraft and is typically associated wi... Loss of Control (LOC) is the primary factor responsible for the majority of fatal air accidents during past decade. LOC is characterized by the pilot’s inability to control the aircraft and is typically associated with unpredictable behavior, potentially leading to loss of the aircraft and life. In this work, the minimum time dynamic optimization problem to LOC is treated using Pontryagin’s Maximum Principle (PMP). The resulting two point boundary value problem is solved using stochastic shooting point methods via a differential evolution scheme (DE). The minimum time until LOC metric is computed for corresponding spatial control limits. Simulations are performed using a linearized longitudinal aircraft model to illustrate the concept. 展开更多
关键词 pilot ASSISTANCE Loss of control Aircrafts Dynamic Optimization TEMPORAL PREDICTION Pontryagin Maximum Principle Differential Evolution Stochastic SHOOTING Point Methods
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碳排放双控效果评估与绿色创新机制:基于自由贸易试验区建设的证据 被引量:2
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作者 李少林 邵东旭 薛寒忆 《环境科学》 北大核心 2025年第3期1558-1572,共15页
伴随着先行先试改革创新经验的复制推广与制度型开放内涵的不断深化,探索绿色低碳模式上升为国家推动自由贸易试验区高质量发展的一项重要举措.聚焦自由贸易试验区制度创新核心任务,测度量化了各片区绿色投资自由化和绿色贸易便利化水平... 伴随着先行先试改革创新经验的复制推广与制度型开放内涵的不断深化,探索绿色低碳模式上升为国家推动自由贸易试验区高质量发展的一项重要举措.聚焦自由贸易试验区制度创新核心任务,测度量化了各片区绿色投资自由化和绿色贸易便利化水平,运用组群-时期平均处理效应估计法(CATT)、插补法(imputation)和堆叠法(stacked DID)等前沿方法探究了自由贸易试验区的碳排放双控效应.结果表明:①自由贸易试验区的分批次设立使碳排放总量下降27.40%,碳排放强度下降14.30%.②自由贸易试验区通过外资进入的绿色创新溢出效应、本土企业的绿色创新直接效应和数字贸易的绿色创新间接效应实现碳排放双控.③市场准入负面清单的全面实施、我国与其他国家签订实施自由贸易协定和国际绿色贸易壁垒的增大,均对自由贸易试验区的碳排放双控产生了显著的正向调节效应.④自由贸易试验区的碳排放双控效应存在显著的空间溢出特征,在其周边550 km的半径表现出最大效能,使周边城市碳排放总量下降18.30%,碳排放强度下降10.10%.⑤异质性分析表明,制度创新水平和政府职能转变程度较高地区比较低地区的碳排放总量控制效果分别高出13.10%和13.70%,碳排放强度控制效果分别高出8.40%和3.40%“;一带一路”沿线城市碳排放总量控制效果比非沿线城市高出9.60%,碳排放强度高出8.80%;开通中欧班列的城市碳排放总量控制效果比未开通城市高出16.80%,碳排放强度高出7.50%.在对接国际经贸规则和实现高质量发展方面,自由贸易试验区须重点关注新注册登记外资企业进入的绿色低碳资质审查和突破绿色贸易技术性壁垒的先行先试,以高水平开放协同助力我国碳排放双控进程. 展开更多
关键词 碳排放双控 绿色创新 自由贸易试验区 数字贸易 双重差分
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基于知识图谱的新能源汽车交流充电故障研究 被引量:2
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作者 郑春伟 李海岗 +2 位作者 杨秀芳 孟婕 杨全占 《农业装备与车辆工程》 2025年第6期55-59,共5页
新能源汽车的广泛应用使交流充电系统的可靠性成为影响用户体验和产业发展的关键因素,但交流充电故障致因复杂且多维交互,传统诊断方法难以满足高精度和系统性需求。知识图谱技术凭借其整合故障特征和逻辑关系的能力,为故障诊断提供了... 新能源汽车的广泛应用使交流充电系统的可靠性成为影响用户体验和产业发展的关键因素,但交流充电故障致因复杂且多维交互,传统诊断方法难以满足高精度和系统性需求。知识图谱技术凭借其整合故障特征和逻辑关系的能力,为故障诊断提供了新思路,相比传统方法更具优势。以新能源汽车交流充电控制导引电路为基础,结合实际车辆充电监测数据和专家知识,构建了故障知识图谱,并设计了基于事件控制逻辑的故障诊断流程。实践应用结果表明,该流程能快速、准确定位故障点,平均诊断时间缩短35%,且普适性强,适用于多种新能源汽车品牌和型号。 展开更多
关键词 新能源汽车 交流充电故障 知识图谱 交流充电控制导引电路 故障诊断流程
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用能权交易试点政策对全要素能源效率的影响 被引量:1
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作者 束云霞 向斌 +1 位作者 吴玉鸣 鲍曙明 《经济地理》 北大核心 2025年第7期35-45,共11页
提高能源效率可以缓解能源需求压力、推动经济低碳转型,进而实现节能减排与绿色发展。文章在计算2006—2021年中国30个省份全要素能源效率的基础上,将用能权交易试点政策视为一项准自然实验,运用双重差分法、合成控制法等方法探究了用... 提高能源效率可以缓解能源需求压力、推动经济低碳转型,进而实现节能减排与绿色发展。文章在计算2006—2021年中国30个省份全要素能源效率的基础上,将用能权交易试点政策视为一项准自然实验,运用双重差分法、合成控制法等方法探究了用能权交易试点政策对全要素能源效率的影响效果及其作用机制。结果表明:(1)用能权交易试点政策显著提高了全要素能源效率,且这一结论在经过一系列检验后依然稳健。(2)用能权交易试点政策可以通过能源消费结构转型、产业结构升级和绿色技术创新提高全要素能源效率。(3)用能权交易试点政策对福建的全要素能源效率影响最大,四川次之,河南最小,对浙江虽短期出现影响但影响并不显著。研究结论为推进能源市场化改革、提升全要素能源效率提供了理论和实证依据,并为创新城市治理模式、实现可持续发展提供了经验参照。 展开更多
关键词 用能权交易试点 全要素能源效率 能源消费结构 双重差分法 合成控制法 试点省份
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文化资源转化与经济动能跃迁:国家文化试验区政策对城市多维发展的影响——以景德镇国家陶瓷文化传承创新试验区为例 被引量:1
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作者 熊智伟 张毅威 王国财 《景德镇学院学报》 2025年第4期1-9,共9页
在全面推进传统文化创造性转化与创新性发展的国家战略背景下,文化传承创新试验区成为激活区域特色资源、破解传统产业城市转型困境的重要政策探索。本文以2019年设立的景德镇国家陶瓷文化传承创新试验区为例,基于2006—2022年景德镇、... 在全面推进传统文化创造性转化与创新性发展的国家战略背景下,文化传承创新试验区成为激活区域特色资源、破解传统产业城市转型困境的重要政策探索。本文以2019年设立的景德镇国家陶瓷文化传承创新试验区为例,基于2006—2022年景德镇、九江、佛山等城市面板数据,以多维政策效应评估为切入点,构建文化赋能与绿色减排双轮驱动的研究框架;基于合成控制法与中介效应模型,从旅游经济增长与工业污染减排两个层面,量化检验景德镇国家陶瓷文化传承创新试验区建设的多维影响效应。研究发现:1.试验区政策对景德镇发展具有显著促进作用,政策实施后,旅游收入与国内旅游人数增长率较合成对照组高;2.政策通过文化事业支持与文化遗产活化,显著提升了旅游经济规模与质量;3.文化设施的完善促进了公众环保意识提升与产业结构优化,景德镇减排效应在中介模型中通过“文化认同—技术升级”路径实现。研究表明,该政策刺激下的文化资源经济转化需兼顾短期政策赋能与长期创新协同,为同类城市依托文化禀赋实现高质量发展提供经验证据。 展开更多
关键词 国家文化试验区 陶瓷产业 区域经济 合成控制法
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