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Finite Element Analysis of Vehicle Load Effect on Harvesting Energy Properties of a Piezoelectric Unit
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作者 Chunhua Sun Hongbing Wang +1 位作者 Jie Liu Guangqing Shang 《Energy and Power Engineering》 2015年第10期500-508,共9页
To realize the goal of harvesting energy from pavement vibration on a large scale, a new type of piezoelectric harvesting units as the energy transducer has been proposed. The piezoelectric harvesting units are paved ... To realize the goal of harvesting energy from pavement vibration on a large scale, a new type of piezoelectric harvesting units as the energy transducer has been proposed. The piezoelectric harvesting units are paved 40 mm below the asphalt, which is the same as thickness of the top layer of typical asphalt pavement in China. The spacing distance is 2200 mm, which is the same as the one between two tires of a normal vehicle. A mathematical model of the unit is deduced on Meda empirical formula and Hamilton principle and piezoelectric equations. Effects of the external vehicle load on its harvesting energy properties and pavement deformation and stress are analyzed with the finite element method. The results show that the excited voltage is linearly variation with contact pressure while the harvested electrical energy exponential varies with contact pressure. The more the contact pressure is, the larger the harvested electrical energy and the deformation and stress are. The harvested electrical energy also increases with the load frequency. At least 100 mJ of electrical energy can be collected with the proposed piezoelectric harvesting unit. It shows that the technology application of the piezoelectric harvesting energy from pavement is promising. 展开更多
关键词 PAVEMENT Vibration PIEZOELECTRIC HARVESTING unit POSITIVE PIEZOELECTRIC effect FINITE Element Analysis
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Comprehensive therapeutic effect of the stroke rehabilitation unit in a medium-sized comprehensive community hospital
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作者 Xiaohua Fu Hong Wang Jia Sun Haiyan Sun Qingyang Song Yi Liu Hong Li 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第4期375-378,共4页
BACKGROUND: Acute stroke unit (stroke care unit) is developing in some domestic large-sized hospitals, but most stroke patients need stroke rehabilitation unit therapy, so setting stroke rehabilitation unit in medi... BACKGROUND: Acute stroke unit (stroke care unit) is developing in some domestic large-sized hospitals, but most stroke patients need stroke rehabilitation unit therapy, so setting stroke rehabilitation unit in medium-sized comprehensive community hospital (secondary hospital), where medical facility is relatively insufficient, is a new pathway to satisfy stroke patients. OBJECTIVE: To observe the comprehensive effect of developing stroke rehabilitation unit based on the facility of secondary hospital and its feasibility. DESIGN: Non-randomized concurrent controlled observation SETTING: Department of Neurology, Beijing Longfu Hospital PARTICIPANTS: Totally 264 stroke reconvalescents who suffered stroke for 7 days and received treatment in the Department of Neurology, Beijing Longfu Hospital during June 2003 to June 2005 were involved in the study. All the involved patients were confirmed by CT or MRI. The patients were scored by using Modified Edinbergh-Scandinavia stroke scale (SSS) 〉 16 points. Written informed consents were obtained from all the patients. The patients were assigned into 2 groups according to the willing of patients and their relatives: (1)treatment group, in which, there were 134 patients, 76 males and 58 females, aged 43 to 74 years; cerebral infarction was found in 116 cases and cerebral hemorrhage in 18 cases;(2) control group, in which, there were 130 patients, 66 males and 64 females, aged 45 to 77 years, cerebral infarction was found in 115 cases and cerebral hemorrhage in 15 cases. There were significant differences in baseline data of the patients between two groups. METHODS: A same basic treatment was conducted in the patients of the two groups. (1) Patients in the treatment group admitted to stroke rehabilitation unit and received comprehensive rehabilitation treatment. The rehabilitation flow-sheet: randomization-letting the patients of treatment group go into the unit-making comprehensive assessment in the initial stage-making therapy plan-talking with patients and their other family members-general rehabilitation-making metaphase assessment-adjusting therapy plan-making final assessment-letting the patients discharge and doing follow-up visits. (2) The patients in the control group admitted to common wards, and they were encouraged to do activities by themselves in the early stage, but did not receive rehabilitation training under the instructions from professional physicians. MAIN OUTCOME MEASURES: The following assessments were conducted on admission and 7 and 28 days after admission: (1) Severity of stroke and motor function: scored as 0 to 45 points by SSS, the higher points, the severer damage. (2)Activities of daily living: Evaluated by Barthel index, 110 points in total, 110 points meant normal, 0 point meant extremely poor. (3)Mental status: evaluated by Hopkin's symptom scale with a 5-point scoring. The symptom was scored with low to high points. (4)Cognitive function: Quantification measurement was conducted with LOTCA method. The higher points, the better therapeutic effects. RESULTS: (1) Three cases dropped out and one died in the treatment group, 11 cases dropped out and 4 died in the control group. (2)The neurologic impairment points on 7 and 28 days after therapy in the treatment group were lower than those in the control group separately [7 days:(9.73±6.43) points vs. (12.63± 7.87) points, t =2.28, P〈 0.05;28 days:(7.88±4.81) points vs. (9.84±7.03)points, t =2.04, P〈 0.05]. Barthel index on 7 and 28 days after therapy in the treatment group were higher than those in the control group separately [7 days:(54.28±8.38) points vs. (39.76±7.31) points, t =2.206, P 〈 0.05; 28 days: (89.72±7.94) points vs. (67.34±8.63) points, t =2.812, P 〈 0.01]. (4) Patients were allocated into different age groups based on age and evaluated with LOTCA. Results showed that there were no significant differences among different age groups (P 〉 0.05). (5) Totally 160 patients in the two groups accomplished the Hopkin's test, among them, 94 (58.7%) had different mental disorders; Among the patients with mental disorder, depression, obsessive-compulsive and anxiety were found mostly, being 53.8%, 52.5% and 46.2%, respectively. CONCLUSION: (1) Developing stroke rehabilitation unit therapy in the secondary hospital can obviously improve the motor function and activities of daily living of stroke reconvalescents. (2) More than half of the stroke reconvalescents accompany the symptoms of depression, obsessive-compulsive, anxiety and other mental disorders. (3) The cognitive function of stroke reconvalescents is not related to age. 展开更多
关键词 Comprehensive therapeutic effect of the stroke rehabilitation unit in a medium-sized comprehensive community hospital
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A zinc(Ⅱ) MOF based on secondary building units of infinite wavy-shaped chain exhibiting obvious luminescent sense effects
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作者 Kai Li Kunhuan He +3 位作者 Quanwen Li Bin Xia Qinglun Wang Yinghui Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第2期499-501,共3页
A new metal-organic framework (MOF),{[Zn_7 (BPS)_4 (OH)_6 (H_2O)_2]·5 H_2O]_n}(1), (H_2 BPS=4,4′-bibenzoic acid-2,2′-sulfone), based on a wavy and infinite chain-shaped secondary building units, has been synthe... A new metal-organic framework (MOF),{[Zn_7 (BPS)_4 (OH)_6 (H_2O)_2]·5 H_2O]_n}(1), (H_2 BPS=4,4′-bibenzoic acid-2,2′-sulfone), based on a wavy and infinite chain-shaped secondary building units, has been synthesized under solvothermal conditions and characterized by single crystal X-ray diffraction and further confirmed by PXRD, TGA and IR spectrum. The solid-state emission spectra reveal that compound 1 presents strong luminescence emission bands at room temperature. The fluorescent properties of compound 1 in diverse organic solvents indicated that 1 has palpable luminescent sense effects for DMF and DMAC. 展开更多
关键词 METAL-ORGANIC frameworks Secondary building unit SOLID-STATE emission spectra Fluorescent properties LUMINESCENT SENSE effectS
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复合人工湿地对污水厂尾水净化效果及微生物群落研究
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作者 景茜 国洁 +1 位作者 龚嘉星 罗晓 《水处理技术》 北大核心 2026年第1期132-136,152,共6页
为研究人工湿地对城镇污水处理厂尾水的净化效果及其微生物群落特征,以七节河复合湿地为研究对象,进行了一年的跟踪监测,考察复合湿地各处理单元对NH_(4)^(+)-N、COD_(Cr)、TP的去除效果,并通过高通量测序技术分析了水体和沉积物微生物... 为研究人工湿地对城镇污水处理厂尾水的净化效果及其微生物群落特征,以七节河复合湿地为研究对象,进行了一年的跟踪监测,考察复合湿地各处理单元对NH_(4)^(+)-N、COD_(Cr)、TP的去除效果,并通过高通量测序技术分析了水体和沉积物微生物群落的特征和差异。结果表明,大部分月份复合湿地出水水质达到《地表水环境质量标准》(GB 3838-2002)Ⅲ类水质标准,2月、3月、5月、8月、10月存在超标现象。沉积物中的细菌多样性和丰富度均高于水体,微生物中高丰度的绿弯菌门可在一定程度上指示出水情况。 展开更多
关键词 人工湿地 污水厂尾水 净化效果 净化单元 微生物群落
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塔群效应对间冷塔热力特性的影响及其流场优化
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作者 陈亚思 刘伟 +3 位作者 程菲 黄茂原 米玉鸿 赵元宾 《中国电机工程学报》 北大核心 2026年第4期1519-1529,I0018,共12页
环境风对自然通风干式冷却塔(间冷塔)冷却性能产生不利影响。在塔群环境,迎风侧塔受环境风的冲击作用更大。研究环境风条件下迎风侧塔的流场优化措施对其冷却性能及其背风侧塔冷却性能的影响,对于间冷塔塔群布置及塔群效应抑制具有重要... 环境风对自然通风干式冷却塔(间冷塔)冷却性能产生不利影响。在塔群环境,迎风侧塔受环境风的冲击作用更大。研究环境风条件下迎风侧塔的流场优化措施对其冷却性能及其背风侧塔冷却性能的影响,对于间冷塔塔群布置及塔群效应抑制具有重要的意义。该文针对某2×660MW间冷机组间接空冷塔塔群,建立气侧流动传热的三维数值模型;结合百叶窗导流装置与气侧均流装置的间冷塔内外流场协同优化,在塔群环境中,研究不同侧风条件和机组负荷时内外流场协同优化对迎风侧塔空气流场和热力特性的优化机制。结果表明:在侧风环境下,间冷塔内外流场协同优化显著提高了迎风侧塔的冷却性能;当环境风速为2.9m/s、机组负荷为100%时,增设内外流场协同优化装置可使迎风侧塔出水温度降低0.964℃,使背风侧塔降低0.628℃。综上,迎风侧塔内外流场协同优化,可有效抑制环境风对间冷塔塔群环境中迎风侧塔和背风侧塔冷却性能的不利影响。 展开更多
关键词 自然通风干式冷却塔 塔群效应 机组负荷 环境侧风 耦合空气动力场优化
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基于不同培养基与微生物检测方法的口腔综合治疗台水路消毒效果评价
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作者 王芃鹏 黄燕春 +4 位作者 王璐 游佳 李小静 陈西卉 张菊 《中华医院感染学杂志》 北大核心 2026年第1期131-134,共4页
目的 探讨不同培养基及微生物检测方法组合下口腔综合治疗台水路(DUWLs)消毒效果评价差异,为DUWLs水样检测提供科学依据。方法 采用随机抽样法对成都市某区15家基层医疗机构35台口腔综合治疗台进行水样采集。每份水样分别采用2种培养基(... 目的 探讨不同培养基及微生物检测方法组合下口腔综合治疗台水路(DUWLs)消毒效果评价差异,为DUWLs水样检测提供科学依据。方法 采用随机抽样法对成都市某区15家基层医疗机构35台口腔综合治疗台进行水样采集。每份水样分别采用2种培养基(R2A培养基、NA培养基)、3种微生物检测方法(倾注法、涂抹法、滤膜法)共6种组合进行微生物检测。采用χ2检验分析不同培养基与微生物检测方法间DUWLs消毒效果合格率差异。结果 最终采集DUWLs样本量为122份,共制作培养基平板732份。针对不同培养基及微生物检测方法进行分层分析,结果发现采用倾注法及涂抹法的两个培养基间DUWLs消毒效果合格率差异较大,具有统计学意义(P<0.001),采用倾注法的两种培养基合格率分别为97.54%(119/122)、72.13%(88/122);采用涂抹法的两种培养基合格率分别为94.26%(115/122)、77.87%(95/122)。采用R2A培养基的3种微生物检测方法对DUWLs消毒效果合格率分别为72.13%(88/122)、77.87%(95/122)、90.98(111/122),差异具有统计学意义(P<0.001)。结论 R2A培养基与倾注法或涂抹法的组合更能准确评价DUWLs消毒效果,建议在条件允许情况下尽量采用该组合进行DUWLs水样微生物检测。 展开更多
关键词 口腔综合治疗台 水样检测 检验方法 消毒效果 R2A培养基
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After Effects特效在电视栏目片头中的应用研究与实现 被引量:1
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作者 伍丽媛 宋健华 《电脑知识与技术》 2015年第3期225-227,232,共4页
随着计算机技术的不断发展,After Effects功能不断提升,越来越被广大影视后期制作者喜爱,其中After Effects特效常被用于制作栏目片头,在主题表现中起着举足轻重的作用。文章主要介绍After Effects及其特效,并通过一个实例制作展现... 随着计算机技术的不断发展,After Effects功能不断提升,越来越被广大影视后期制作者喜爱,其中After Effects特效常被用于制作栏目片头,在主题表现中起着举足轻重的作用。文章主要介绍After Effects及其特效,并通过一个实例制作展现After Effects特效在栏目片头中运用。 展开更多
关键词 Aftere Efects 栏目片头 特效 插件 电视栏目
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四级康复护理活动方案配合物理康复疗法促进重症监护室获得性衰弱患者早期康复的效果
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作者 张跃强 王颖 +2 位作者 李春朋 袁俊红 卫晓静 《河南医学研究》 2026年第4期719-722,共4页
目的探究四级康复护理活动方案配合物理康复疗法对促进重症监护室获得性衰弱(ICU-AW)患者的早期康复作用。方法前瞻性研究,收集2023年7月至2024年12月河南省人民医院重症医学科108例患者,用随机数字表法划分两组,即研究组与对照组,各54... 目的探究四级康复护理活动方案配合物理康复疗法对促进重症监护室获得性衰弱(ICU-AW)患者的早期康复作用。方法前瞻性研究,收集2023年7月至2024年12月河南省人民医院重症医学科108例患者,用随机数字表法划分两组,即研究组与对照组,各54例,分别给予四级康复护理活动方案配合物理康复疗法、单纯物理康复疗法。对比两组患者肌力、急性生理学与慢性健康状况评分Ⅱ(APACHEⅡ)、ICU活动量表(IMS)评分、生活自理能力及ICU-AW发生率。结果干预后,研究组MRC、IMS及Barthel指数评分高于对照组(P<0.05);APACHEⅡ评分低于对照组(P<0.05)。对照组ICU-AW发生率高于研究组(P<0.05)。结论四级康复护理活动方案配合物理康复疗法能够有效预防或减少ICU-AW的发生,并提升患者肌力水平、自理能力以及ICU活动能力,缓解病情严重程度。 展开更多
关键词 四级康复护理活动方案 物理康复 重症监护室获得性衰弱 康复效果
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考虑时空效应的小域估计模型的理论发展与应用研究
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作者 李采霞 于力超 《数理统计与管理》 北大核心 2026年第1期49-66,共18页
小域估计是抽样调查领域中的重要问题,当区域样本量较小甚至为零时,直接估计法难以满足参数估计精度要求,借助相关区域或相关时点的辅助信息提高参数的估计精度十分必要。基于模型的小域估计通过建立混合模型利用共同参数融合不同区域... 小域估计是抽样调查领域中的重要问题,当区域样本量较小甚至为零时,直接估计法难以满足参数估计精度要求,借助相关区域或相关时点的辅助信息提高参数的估计精度十分必要。基于模型的小域估计通过建立混合模型利用共同参数融合不同区域的信息成为目前小域估计的主流方法,但常规的小域估计模型没有考虑区域之间的空间相关性,以及目标区域的历史调查数据。为此,本文分别将常规的域层次和单元层次小域估计模型拓展为考虑时间效应、考虑空间效应和同时考虑时空效应的小域估计模型。然后,基于这些考虑时空效应的小域估计模型中线性参数的经验最优线性无偏预测(EBLUP),阐释了其估计过程中未知参数的限制极大似然(REML)估计方法,以及使用参数自助法计算预测量均方误差(MSE)的方法。最后,利用广西壮族自治区14个地级市2018-2020年的城镇登记失业率数据对模型的参数估计效果进行实证分析,结果显示:同时考虑时间和空间效应的小域估计模型下目标参数估计效果更好,基于分析结果,从加大教育投资力度、繁荣第三产业市场以及加强地区间剩余劳动力转移等方面提出了稳定就业市场的政策建议。 展开更多
关键词 小域估计 域层次模型 单元层次模型 时空效应 参数自助法
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基于失效模式与效应分析法的护理管理对PICU医院感染的控制效果分析
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作者 黄玘宁 黄文娟 +1 位作者 刘莉莉 刘文静 《贵州医药》 2026年第2期289-291,共3页
目的 儿科重症监护病房(PICU)医院感染采取基于失效模式与效应分析法(FMEA)共同应用的效果分析。方法 选取本院收治的90例PICU患儿,根据抽签法分为联合组与对照组每组45例,对照组开展常规的PICU护理流程,联合组在传统护理模式的基础上结... 目的 儿科重症监护病房(PICU)医院感染采取基于失效模式与效应分析法(FMEA)共同应用的效果分析。方法 选取本院收治的90例PICU患儿,根据抽签法分为联合组与对照组每组45例,对照组开展常规的PICU护理流程,联合组在传统护理模式的基础上结合FMEA方法进行风险管理,比较两组控制感染效果、满意度。结果 护理后,联合组PICU患儿病原检出率相比对照组更低(P<0.05);联合组患儿医院感染的发生率低于对照组(P<0.05);护理后,联合组临床护理满意度优于对照组(P<0.05)。结论 儿科PICU医院感染采取FMEA具有较好的控制效果,可有效减少医院感染情况的发生,提升临床护理满意度。 展开更多
关键词 基于失效模式与效应分析法 儿科重症监护病房 医院感染 控制效果 护理满意度
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利用轨迹数据计算典型人类活动空间特征的时间聚合效应
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作者 赵志远 祝章伟 +2 位作者 吴升 汪艳霞 胡慧芳 《地理科学》 北大核心 2026年第3期542-553,共12页
轨迹记录数据被广泛用于计算人类活动空间特征和挖掘人类活动规律。当原始轨迹数据记录的时间采样间隔不同时,对移动对象位置信息的时间观测尺度随之变化,计算的人类活动特征数值和分析结果可能会受到影响,即为时间聚合效应。为此,本研... 轨迹记录数据被广泛用于计算人类活动空间特征和挖掘人类活动规律。当原始轨迹数据记录的时间采样间隔不同时,对移动对象位置信息的时间观测尺度随之变化,计算的人类活动特征数值和分析结果可能会受到影响,即为时间聚合效应。为此,本研究利用志愿者123 d长时序高频采样的手机数据,从4个维度选择了6个典型的人类活动空间特征指标进行分析。研究结果显示:(1)基于轨迹记录数据计算的典型人类活动空间特征存在时间聚合效应,即随时间采样间隔增加,指标数值整体被低估,但不同指标被低估程度存在差异;(2)对短持续时间活动存在依赖的指标(如日出行距离、日出行频次、日出行空间结构)受影响程度显著,侧重刻画长持续活动时空特征的指标(如日最大活动范围、日活动锚点个数量等)受影响程度较低,综合性指标(如活动位置熵)受影响程度居中;(3)采样时间间隔超过30 min时,除了日出行距离之外,其他指标变化程度在个体之间的一致性较好。本研究关于时间聚合效应的定量化评估结果有助于深化对基于轨迹数据的人类活动空间特征分析结果的理解,提升决策支撑的科学性。 展开更多
关键词 手机位置数据 人类移动性 时间聚合效应 时间采样间隔 可塑时间单元问题(MTUP)
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Acupuncture's Role in Solving the Opioid Epidemic: Evidence, Cost-Effectiveness, and Care Availability for Acupuncture as a Primary, Non-Pharmacologic Method for Pain Relief and Management-White Paper 2017 被引量:35
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作者 arthur yin fan david w.miller +11 位作者 bonnie bolash matthew bauer john mcdonald sarah faggert hongjian he yong ming li amy matecki lindy camardella mel hopper koppelman jennifer a.m.stone lindsay meade john pang 《Journal of Integrative Medicine》 SCIE CAS CSCD 2017年第6期411-425,共15页
The United States (U.S.) is facing a national opioid epidemic, and medical systems are in need of non- pharmacologic strategies that can be employed to decrease the public's opioid dependence. Acupuncture has emerg... The United States (U.S.) is facing a national opioid epidemic, and medical systems are in need of non- pharmacologic strategies that can be employed to decrease the public's opioid dependence. Acupuncture has emerged as a powerful, evidence-based, safe, cost-effective, and available treatment modality suitable to meeting this need. Acupuncture has been shown to be effective for the management of numerous types of pain conditions, and mechanisms of action for acupuncture have been described and are understandable from biomedical, physiologic perspectives. Further, acupuncture's cost-effectiveness can dramatically decrease health care expenditures, both from the standpoint of treating acute pain and through avoiding addiction to opioids that requires costly care, destroys quality of life, and can lead to fatal overdose. Numerous federal regulatory agencies have advised or mandated that healthcare systems and providers offer non-pharmacologic treatment options for pain. Acupuncture stands out as the most evidence-based, immediately available choice to fulfil these calls. Acupuncture can safely, easily, and cost-effectively be incorporated into hospital settings as diverse as the emergency department, labor and delivery suites, andneonatal intensive care units to treat a variety of commonly seen pain conditions. Acupuncture is already being successfully and meaningfully utilized by the Veterans Administration and various branches of the U.S. Military, in some studies demonstrably decreasing the volume of opioids prescribed when included in care. 展开更多
关键词 ACUPUNCTURE opioid epidemic pain opiate dependency effectiveness safety COST-effectIVENESS mechanism united States
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Evaluation of Economic, Social Effects of Renewable Energy Technologies 被引量:2
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作者 Lucio Laureti Marco Giuseppe Lupis Rogges Alberto Costantiello 《Journal of Environmental Protection》 2018年第11期1143-1154,共12页
What is sustainability? Does it only concern the environment or even socio-economic policies? It is only a question of ethics or a redefinition of industrial policy oriented towards the use of renewable energy, it can... What is sustainability? Does it only concern the environment or even socio-economic policies? It is only a question of ethics or a redefinition of industrial policy oriented towards the use of renewable energy, it can bring benefits both atmospheric and social employment. The need for the development of renewable sources can be in tune with the correct management of the territory in consideration of the fact that these sources involve the widespread implementation of small and medium-sized plants. A model of economic development based on renewable sources should respect the peculiarities and characteristics of the territories involved. It should also think of the territory as a “value” to be strengthened and used in a sustainable and integrated way and no longer as a passive platform on which to install plants. Solar thermal and photovoltaic, biomass, geothermal, hydrological, wind power are some of the sources the various countries must constantly invest. This publication is based on these concepts starting from an analysis of the employment data of the OECD “Organisation for Economic Co-operation and Development countries”, comparing them successively with the results of renewable energy productivity. The analysis was performed by analyzing a sample of 22 countries over a period of 20 years, after which the regression curve for the variables with the OLS method was created. This econometric method has allowed us to analyze the impact that renewable technologies have on the parameters of social welfare and in particular on unemployment. 展开更多
关键词 RENEWABLE Energy SECTOR UNEMPLOYMENT Panel unit ROOTS CAUSALITY Fixed effectS Model Social effectS Sustainability
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A Novel Approach for the Effective Thermal Conductivity of Porous Ceramics 被引量:8
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作者 ZHU Qiang ZHANG Fan-wei +2 位作者 ZHANG Yue ZHANG Da-hai LI Zhong-ping 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2006年第B12期244-247,共4页
A new approach in combination of the effective medium theory with the equivalent unit in numerical simulation was developed to study the effective thermal conductivity of porous ceramics. The finite element method was... A new approach in combination of the effective medium theory with the equivalent unit in numerical simulation was developed to study the effective thermal conductivity of porous ceramics. The finite element method was used to simulate the heat transfer process which enables to acquire accurate results through highly complicated modeling and intensive computation. An alternative approach to mesh the material into small cells was also presented. The effective medium theory accounts for the effective thermal conductivity of cells while the equivalent unit is subsequently applied in numerical simulation to analyze the effective thermal conductivity of the porous ceramics. A new expression for the effective thermal conductivity, allowing for some structure factors such as volume fraction of pores and thermal conductivity, was put forward, and the results of its application was proved to be close to those of the mathematical simulation. 展开更多
关键词 effective thermal conductivity porous ceramics equivalent unit numerical simulation
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Discussion on Key Points of Wind Load of Jack-up Unit
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作者 林一 胡安康 +1 位作者 熊飞 蒋玮 《China Ocean Engineering》 SCIE EI CSCD 2014年第1期127-138,共12页
The anti-overturning ability and structure safety of jack-up unit in in-place condition are often affected by environment loads, especially wind load. According to the MODU rule, the projected area method is used for ... The anti-overturning ability and structure safety of jack-up unit in in-place condition are often affected by environment loads, especially wind load. According to the MODU rule, the projected area method is used for calculating the wind load. However, the calculated results are conservative and not good for structure optimization design. In this paper, a 400 ft jack-up is studied as an example. Based on the wind tunnel test and numerical simulation method, some key points of wind load calculation, such as shielding effect, lift effect and shape coefficient of component, are discussed. The study shows that the points mentioned above, which are ignored in the MODU rule calculation, result in the conservative result. 展开更多
关键词 jack-up unit wind load shielding effect lift effect shape coefficient
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呼吸衰竭患者ICU获得性吞咽障碍恢复时间与住院时间的关联
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作者 尚晓卉 田小红 +2 位作者 刘宁宁 李跃 伏冉 《东南大学学报(医学版)》 2026年第1期119-127,共9页
目的:探究呼吸衰竭患者ICU获得性吞咽障碍恢复时间与住院时间的关联及阈值效应。方法:采用便利抽样法,选取2020年7月至2024年8月本院呼吸衰竭伴ICU获得性吞咽障碍患者为研究对象。收集患者的一般资料;Spearman相关分析吞咽障碍恢复时间... 目的:探究呼吸衰竭患者ICU获得性吞咽障碍恢复时间与住院时间的关联及阈值效应。方法:采用便利抽样法,选取2020年7月至2024年8月本院呼吸衰竭伴ICU获得性吞咽障碍患者为研究对象。收集患者的一般资料;Spearman相关分析吞咽障碍恢复时间与住院时间的相关性;多因素线性回归分析住院时间的影响因素;采用平滑曲线拟合吞咽障碍恢复时间与住院时间之间的剂量-反应关系;阈值效应分析定量影响,并对不同特征人群进行分层亚组分析。结果:203例患者住院时间为9~45 d,中位住院时间为18(14,21)d;吞咽障碍恢复时间为12~289 h,中位恢复时间为62(29,84)h。Spearman相关分析显示,吞咽障碍恢复时间与住院时间呈正相关(r=0.576,P<0.05)。多因素线性回归显示,吞咽障碍恢复时间、有营养风险、APACHEⅡ评分≥15分是呼吸衰竭伴ICU获得性吞咽障碍患者住院时间的影响因素(均P<0.05),可共同解释住院时间61.8%的变异度。平滑曲线显示,调整全部协变量后吞咽障碍恢复时间与住院时间存在正向非线性关系,患者的住院时间随吞咽障碍恢复时间增加而有延长趋势。调整全部协变量后,吞咽障碍恢复时间和住院时间的关联存在阈值效应(P_(for likelihood ratio test)=0.003)。当吞咽障碍恢复时间<62 h时,吞咽障碍恢复时间与住院时间的关联并不显著(β=0.035,95%CI:-0.022~0.092,P>0.05);而当吞咽障碍恢复时间≥62 h时,随吞咽障碍恢复时间每增加1 h,患者住院时间延长0.121 d(β=0.121,95%CI:0.102~0.140,P<0.05)。吞咽障碍恢复时间与住院时间的关系在不同性别、年龄、体质量指数、高血压、糖尿病、冠心病、APACHEⅡ评分、营养风险人群中差异无统计学意义(交互作用,均P>0.05)。结论:呼吸衰竭伴ICU获得性吞咽障碍患者吞咽障碍恢复时间与APACHEⅡ评分、营养风险均影响住院时间;吞咽障碍恢复时间与住院时间还存在独立正向非线性关联,当吞咽障碍恢复时间≥62 h时住院时间明显延长。 展开更多
关键词 呼吸衰竭 ICU 获得性吞咽障碍 住院时间 恢复时间 平滑曲线 阈值效应
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Characterizing the Urban Temperature Trend Using Seasonal Unit Root Analysis:Hong Kong from 1970 to 2015
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作者 Wai-Ming TO Tat-Wai YU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第12期1376-1385,共10页
This paper explores urban temperature in Hong Kong using long-term time series. In particular, the characterization of the urban temperature trend was investigated using the seasonal unit root analysis of monthly mean... This paper explores urban temperature in Hong Kong using long-term time series. In particular, the characterization of the urban temperature trend was investigated using the seasonal unit root analysis of monthly mean air temperature data over the period January 1970 to December 2013. The seasonal unit root test makes it possible to determine the stochastic trend of monthly temperatures using an autoregressive model. The test results showed that mean air temperature has increased by 0.169~ C (10 yr) - 1 over the past four decades. The model of monthly temperature obtained from the seasonal unit root analysis was able to explain 95.9% of the variance in the measured monthly data -- much higher than the variance explained by the ordinary least-squares model using annual mean air temperature data and other studies alike. The model accurately predicted monthly mean air temperatures between January 2014 and December 2015 with a root-mean-square percentage error of 4.2%. The correlation between the predicted and the measured monthly mean air temperatures was 0.989. By analyzing the monthly air temperatures recorded at an urban site and a rural site, it was found that the urban heat island effect led to the urban site being on average 0.865~C warmer than the rural site over the past two decades. Besides, the results of correlation analysis showed that the increase in annual mean air temperature was significantly associated with the increase in population, gross domestic product, urban land use, and energy use, with the R2 values ranging from 0.37 to 0.43. 展开更多
关键词 urban temperature trend urban heat island effect seasonal unit root tests long-term time series
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数字还是单位更重要:颜色的调节作用
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作者 李晓明 周慧雯 +1 位作者 苏静怡 孟员 《心理科学》 北大核心 2025年第1期153-163,共11页
数量信息由具体数字和表明其本质的单位构成,研究通过2个预研究和3个实验旨在基于解释水平理论探讨不同颜色(黑白或彩色)背景下数字与单位信息在数量信息评估中的相对优势及其对随后选择偏好的影响。结果发现,颜色会调节数量信息判断过... 数量信息由具体数字和表明其本质的单位构成,研究通过2个预研究和3个实验旨在基于解释水平理论探讨不同颜色(黑白或彩色)背景下数字与单位信息在数量信息评估中的相对优势及其对随后选择偏好的影响。结果发现,颜色会调节数量信息判断过程中的数字效应与单位效应,进而影响其选择偏好。具体而言,个体在彩色条件下会更关注数字信息,表现为数字效应;在黑白条件下则会更关注单位信息,表现为单位效应。这可能因为不同颜色条件下个体的解释水平(黑白-高解释水平、彩色-低解释水平)会发生变化,进而影响了其对数字与单位的关注程度,从而表现出不同的数量效应。 展开更多
关键词 颜色 数字效应 单位效应 解释水平理论
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运用HFMEA结合环节质量强化管理对呼吸重症监护病房VAP防控效果的研究
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作者 李国飞 钟小锋 +2 位作者 王舒扬 王泳 罗艺 《中国感染控制杂志》 北大核心 2026年第1期68-75,共8页
目的探讨医疗失效模式与效应分析(HFMEA)结合环节质量强化管理作为联合策略对呼吸重症监护病房(RICU)呼吸机相关肺炎(VAP)的防控效果,为优化临床感染控制流程提供依据。方法采用回顾性研究方法,对照组选取2023年1—12月武汉市肺科医院R... 目的探讨医疗失效模式与效应分析(HFMEA)结合环节质量强化管理作为联合策略对呼吸重症监护病房(RICU)呼吸机相关肺炎(VAP)的防控效果,为优化临床感染控制流程提供依据。方法采用回顾性研究方法,对照组选取2023年1—12月武汉市肺科医院RICU接受常规管理进行VAP防控的有创机械通气患者;试验组选取2024年1—12月同一医院、同一科室采用HFMEA联合环节质量强化管理进行VAP防控的同类患者。比较两组患者的VAP防控关键环节质量评分、防控措施依从率、VAP发病率及不同管理模式下医务人员满意度等方面的差异。结果对照组129例患者,机械通气日1526 d;试验组161例患者,机械通气日1409 d。VAP防控关键环节质量评分总分对照组为(60.15±5.52)分,试验组为(90.00±4.05)分;试验组总分及各环节质量评分均高于对照组,差异均有统计学意义(均P<0.05)。VAP防控核心措施依从率对照组为62.64%,试验组为85.09%;试验组总依从率及各项措施的依从率均高于对照组,差异均有统计学意义(均P<0.05)。试验组患者的平均机械通气时间为(8.75±4.20)d,较对照组的(11.83±5.80)d缩短,差异具有统计学意义(P<0.001)。试验组VAP发病率为9.23‰,对照组为19.00‰,差异有统计学意义(P=0.026)。试验组医护人员工作满意度为93.94%,对照组为72.73%,差异具有统计学意义(P=0.007),且试验组“非常满意”比率更高(27.27%VS 15.15%)及“不满意”比率更低(6.06%VS 27.27%)。结论运用HFMEA结合环节质量强化管理的联合策略,有助于提升VAP防控措施的执行效能,降低VAP发病率,并提升医务人员对VAP防控的满意度。 展开更多
关键词 医疗失效模式与效应分析 环节质量强化管理 呼吸重症监护病房 呼吸机相关肺炎 感染控制
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Effect of Training Nurses in ICU in Immediate Care Post Cardiac Surgery
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作者 Fathia Saeed Salih’s Mohamed 《World Journal of Cardiovascular Surgery》 2023年第10期154-158,共5页
The specialty of cardiovascular surgical nursing has advanced patient care significantly both before and after surgery, and it is now a well-established field. The primary goal of cardiovascular surgical nursing is to... The specialty of cardiovascular surgical nursing has advanced patient care significantly both before and after surgery, and it is now a well-established field. The primary goal of cardiovascular surgical nursing is to optimize the patient's recovery and prevent complications. Immediate nursing care for post-operative cardiac patients in a state of controlled shock due to fluid shift and varying vascular tone. Aim of the Study: Assessment of nurse’s knowledge and performance after the training program of nursing care immediately after a patient arrives from cardiac surgery. Methods: This pre and post-intervention study was conducted at cardiac centers in Sudan Alshaab and Ahmed Gasim Cardiac Center. The aim of the study was to evaluate the impact on nurses’ performance after training program post open-heart surgery. In the initial phase of the study, all 98 nurses working in the intensive care units at Alshaab and Ahmed Gasim cardiac centers were designated as the study group and evaluated before the intervention. Subsequently, the same group was reassessed after the intervention (phase 2), allowing for a comparison of the pre- and post-intervention results. The assessment involved the use of a specifically designed questionnaire and an observation checklist developed in accordance with the standards recommended by the American Nurses Association (phase 3). Result: Descriptive analysis was performed using the Chi-square test, the difference in the performance between the study group before intervention and after the intervention was assessed by the mean of chi-square significantly was taken as p < 0.05. 展开更多
关键词 effect TRAINING IMMEDIATE Nursing Care Intensive unit
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