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Longevity Internal Elixir—Tradition of Yue School in East Sichuan for Warding off Disease, Keeping in Good Health and Cultivating Mind
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作者 Grace·Tan 《Journal of Advances in Medicine Science》 2018年第4期121-124,共4页
With the continuous improvement of the national economy and people's quality of life, people's attention to human health and health is increasing. Taking exercise and reasonable diet and good living habits to ... With the continuous improvement of the national economy and people's quality of life, people's attention to human health and health is increasing. Taking exercise and reasonable diet and good living habits to adjust the body's meridian operation and promote the continuous optimization of human body function is an important way to achieve healthy development and optimize people's lifestyle. This paper describes the formation and development of Longevity Internal Elixir form Yue School in East Sichuan and its positive effects on human health. It analyzes the implementation methods and steps of Longevity Internal Elixir and points out the precautions and safeguards for the implementation of Longevity Internal Elixir. Through the analysis of this paper, it is clear that Longevity Internal Elixir plays an important role in the health of the people, exerts its role in promoting bodily functions. The implementation methods and safeguard measures of Longevity Internal Elixir are also clarified in this paper. 展开更多
关键词 YUE SCHOOL in East Sichuan warding OFF disease and Keeping in good health LONGEVITY INTERNAL ELIXIR
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Warding off Senility
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作者 TANG YUANKAI 《Beijing Review》 2010年第48期42-42,共1页
Fighting against mental deterioration in ageing lt’s commonly accepted by scientists that if the extension of life is possible,the secrets of senility must be uncovered.
关键词 warding off Senility
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不同载荷条件下三种内固定方式治疗PauwelsⅢ型股骨颈骨折的有限元分析 被引量:3
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作者 李正刚 尚学红 +5 位作者 吴张 李红 孙朝军 陈华东 孙哲 杨毅 《中国组织工程研究》 CAS 北大核心 2025年第3期455-463,共9页
背景:治疗PauwelsⅢ型股骨颈骨折的最佳内固定方式仍未达成共识,既往相关有限元分析大多采用单一简化载荷条件,对于常用内固定装置的生物力学特性还需进一步探究。目的:通过有限元方法分析空心加压螺钉、动力髋螺钉和股骨颈系统治疗Pauw... 背景:治疗PauwelsⅢ型股骨颈骨折的最佳内固定方式仍未达成共识,既往相关有限元分析大多采用单一简化载荷条件,对于常用内固定装置的生物力学特性还需进一步探究。目的:通过有限元方法分析空心加压螺钉、动力髋螺钉和股骨颈系统治疗PauwelsⅢ型股骨颈骨折在单腿站立载荷及侧方跌倒载荷条件下的生物力学特性。方法:通过CT扫描获取健康成人股骨DICOM数据,导入Mimics 15.0软件,得到骨组织的粗糙模型,再通过Geomagics软件对Mimics导出的数据进行优化处理,然后根据空心加压螺钉、动力髋螺钉和股骨颈系统的临床应用参数采用Pro/E软件建立3种内固定模型并与股骨模型组装,最后导入Ansys软件进行加载、计算,分析3种内固定模型在单腿站立载荷及侧方跌倒载荷的不同工况下股骨和内固定的应力分布和位移情况,以及股骨距和Ward三角区的应力特点。结果与结论:(1)单腿站立载荷及侧方跌倒载荷下,3种内固定模型的股骨近端应力均主要分布在股骨颈骨折端内上方,3种内固定模型的股骨近端、骨折端、Ward三角以及股骨距的应力峰值均为股骨颈系统内固定模型最小,空心加压螺钉内固定模型最大;(2)单腿站立载荷及侧方跌倒载荷下,3种内固定模型的股骨近端位移峰值均位于股骨头顶端,且位移峰值均为股骨颈系统内固定模型最小,空心加压螺钉内固定模型最大;(3)3种内固定模型在单腿站立及侧方跌倒载荷条件下内固定的位移峰值均位于内固定装置上方顶端,且位移峰值均为股骨颈系统内固定模型最小,空心加压螺钉内固定模型最大;(4)3种内固定模型在单腿站立及侧方跌倒载荷条件下内固定的应力均主要集中在内固定装置的骨折端附近区域,且内固定应力峰值均为股骨颈系统内固定模型最小,空心加压螺钉内固定模型最大;(5)结果表明,股骨颈系统的机械稳定性最佳,但是可能存在对于骨折端和股骨距应力遮挡的风险;股骨颈系统的内固定装置应力更为分散,内固定断裂风险更低。 展开更多
关键词 股骨颈骨折 内固定 有限元分析 生物力学 单腿站立 侧方跌倒 股骨距 Ward三角
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Digital health technologies/interventions in smart ward development for elderly patients with diabetes:A perspective from China and beyond 被引量:1
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作者 Wei Yang Juan Lu +5 位作者 Si-Cong Si Wei-Hua Wang Jing Li Yi-Xin Ma Huan Zhao Jia Liu 《World Journal of Diabetes》 2025年第4期62-73,共12页
Diabetes is highly prevalent among the elderly worldwide,with the highest number of diabetes cases in China.Yet,the management of diabetes remains unsatisfactory.Recent advances in digital health technologies have fac... Diabetes is highly prevalent among the elderly worldwide,with the highest number of diabetes cases in China.Yet,the management of diabetes remains unsatisfactory.Recent advances in digital health technologies have facilitated the establishment of smart wards for diabetes patients.There is a lack of smart wards tailored specifically for older diabetes patients who encounter unique challenges in glycemic control and diabetes management,including an increased vulnerability to hypoglycemia,the presence of multiple chronic diseases,and cognitive decline.In this review,studies on digital health technologies for diabetes in China and beyond were summarized to elucidate how the adoption of digital health technologies,such as real-time continuous glucose monitoring,sensor-augmented pump technology,and their integration with 5th generation networks,big data cloud storage,and hospital information systems,can address issues specifically related to elderly diabetes patients in hospital wards.Furthermore,the challenges and future directions for establishing and implementing smart wards for elderly diabetes patients are discussed,and these challenges may also be applicable to other countries worldwide,not just in China.Taken together,the smart wards may enhance clinical outcomes,address specific issues,and eventually improve patient-centered hospital care for elderly patients with diabetes. 展开更多
关键词 Diabetes Elderly care Digital health technology Smart ward Wearable devices Continuous glucose monitoring Sensor-augmented pump
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三峡库区湿地植物群落类型、物种多样性与生物量变化特征
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作者 殷凡 郑杰 +3 位作者 陈洋溢 耿倩雯 刘俊臣 李昌晓 《生态学报》 北大核心 2025年第14期6923-6933,共11页
为了明确三峡库区湿地不同植物群落类型物种多样性与生物量变化特征及其影响因素,研究选取三峡库区湿地生态系统为研究对象,采用Ward聚类的方法对三峡库区湿地植物群落进行分类,并利用回归分析方法明确库区湿地植物群落的物种多样性与... 为了明确三峡库区湿地不同植物群落类型物种多样性与生物量变化特征及其影响因素,研究选取三峡库区湿地生态系统为研究对象,采用Ward聚类的方法对三峡库区湿地植物群落进行分类,并利用回归分析方法明确库区湿地植物群落的物种多样性与地上生物量之间的关系。结果表明,三峡库区湿地植物群落有8个类型,即芦竹群落、长芒稗-酸模叶蓼群落、白茅-牛鞭草群落、狼耙草-牛鞭草群落、狗牙根群落、西来稗群落、异型莎草-狗牙根群落、艾-狗牙根群落,不同群落类型之间的物种多样性和地上生物量有显著的差异(P<0.05)。回归分析结果明确研究区湿地植物群落的地上生物量与物种多样性水平呈显著的线性负相关关系,表明三峡库区湿地植物群落物种多样性与地上生物量之间存在一定的权衡关系。结构方程模型对地理因子、气候因子和土壤因子对物种多样性和地上生物量的直接和间接影响分析发现,地理因子通过调控气候和土壤因子间接影响物种多样性和地上生物量,气候和土壤因子均直接影响物种多样性和地上生物量。研究结果揭示了环境因子对物种多样性和地上生物量的综合调控机制,为三峡库区湿地及类似湿地生态系统的植物群落保护和恢复提供参考。 展开更多
关键词 湿地植物群落 Ward聚类 物种多样性 生物量-多样性关系
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A Study of Disease Writing in Sing,Unburied,Sing
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作者 SU Xue-qi 《Journal of Literature and Art Studies》 2025年第5期357-365,共9页
This paper examines the disease writing in Jesmyn Ward’s Sing,Unburied,Sing,focusing on its metaphorical implications at three levels.Through an analysis of three central diseases-Mam’s cancer,Leonie’s drug addicti... This paper examines the disease writing in Jesmyn Ward’s Sing,Unburied,Sing,focusing on its metaphorical implications at three levels.Through an analysis of three central diseases-Mam’s cancer,Leonie’s drug addiction,and Kayla’s fever and vomiting,this study reveals how Ward employs illness as a lens to critique systemic racism,social injustice,and intergenerational trauma in the American South.Mam’s cancer symbolizes emotional repression and historical wounds inflicted upon Black Americans,while Leonie’s addiction reflects both personal escapism and the destructive consequences of racial and social marginalization.Kayla’s symptoms,along with other people’s symtom of vomiting,serve as visceral expressions of psychological rejection and resistance to oppression.Drawing on Sontag’s theories of illness as metaphor,the paper argues that Ward’s disease narratives transcend individual suffering,exposing the pervasive“diseases”of racism and inequality in society.The novel’s portrayal of illness underscores the resilience of Black communities and the urgent need for collective healing from cultural trauma. 展开更多
关键词 SING Unburied SING Jasmine Ward disease writing
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Identification of risk factors for Clostridium difficile infection in older adult hospitalized patients with pressure ulcers
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作者 Qin Jiang Dong-Xin Liu +3 位作者 Wei Lu Hong-Fei Sang Xiao-Mei Gong Yu-Lei Li 《World Journal of Gastroenterology》 2025年第36期122-128,共7页
BACKGROUND Clostridium difficile(C.difficile)infection(CDI)is a common healthcare-associated infection.Older adult hospitalized patients with pressure ulcers are more sus-ceptible because of low immunity and disordere... BACKGROUND Clostridium difficile(C.difficile)infection(CDI)is a common healthcare-associated infection.Older adult hospitalized patients with pressure ulcers are more sus-ceptible because of low immunity and disordered flora,but their specific risk factors are unknown.This study hypothesizes that the use of antibiotics for more than 2 weeks,the use of proton pump inhibitors(PPIs),and the use ofβ-lactam antibiotics are independent risk factors for CDI in this population.METHODS A total of 120 older adults hospitalized with pressure ulcers from 2020 to 2023 were enrolled in the wound repair ward of the hospital.Stool samples were collected for anaerobic culture,C.difficile glutamate dehydrogenase(GDH)anti-gen and toxin detection,and multivariate logistic regression was used to analyze risk factors.RESULTS Among 120 older adults hospitalized patients with pressure ulcers,39 tested po-sitive for C.difficile,with an incidence rate of 32.5%.Thirty-nine patients(32.5%)were positive for GDH antigen.Twelve patients(10.0%)were positive for toxin A/B.Multivariate analysis shows that the use of antibiotics for more than 2 weeks,the use of proton pump inhibitors,and the use ofβ-lactam antibiotics are independent risk factors for CDI(all P values<0.05).CONCLUSION From 2020 to 2023,the incidence of CDI in 120 hospitalized older adult patients with pressure ulcers was 32.5%,and three independent risk factors were identified. 展开更多
关键词 Older adult patients Pressure ulcers Wound repair ward Clostridium difficile INFECTION Risk factors DETECTION
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Evidence-based Design of Naturalized Decoration in HSCT Wards of Peking University First Hospital
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作者 DENG Huiwen WANG Xiaobo +1 位作者 WANG Yuxin WANG Hefei 《Journal of Landscape Research》 2025年第1期68-73,共6页
In this study,the evidence-based design(EBD)of naturalized decoration in hematopoietic stem cell transplantation(HSCT)wards of Peking University First Hospital was explored to improve patients’psychological state and... In this study,the evidence-based design(EBD)of naturalized decoration in hematopoietic stem cell transplantation(HSCT)wards of Peking University First Hospital was explored to improve patients’psychological state and rehabilitation environment by introducing natural elements.Based on questionnaire surveys and literature research,the EBD method was adopted to propose a naturalized decoration scheme for HSCT wards,and a satisfaction evaluation was conducted after construction and use.The research results show that naturalized decoration can effectively enhance the satisfaction and comfort of patients and medical staff,verifying its positive effects in HSCT wards. 展开更多
关键词 Naturalized decoration Evidence-based design HSCT wards Patient rehabilitation Satisfaction evaluation
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Analysis of the Effect of Safety Culture Construction in Nursing Management of Infectious Disease Area
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作者 Xing Wang Jing Wang +1 位作者 Yu Wu Yang Yu 《Journal of Clinical and Nursing Research》 2025年第3期100-105,共6页
Objective:To explore the effect of applying safety culture construction in nursing management of infectious disease areas.Methods:During the one-year period from January 2024 to December 2024,patients admitted to the ... Objective:To explore the effect of applying safety culture construction in nursing management of infectious disease areas.Methods:During the one-year period from January 2024 to December 2024,patients admitted to the infectious disease area of our hospital were randomly selected for the study.92 patients were divided into two groups using a computerized double-blind method for intervention.The control group received routine nursing management,while the observation group applied safety culture construction management.The effects of nursing management in the two groups were studied and compared.Results:Before management,the nursing management quality scores of the two groups were evaluated,showing little difference in various scores,and the difference was not statistically significant(P>0.05).Through the implementation of nursing management,the scores of the two groups were significantly improved,and the observation group had significantly higher scores compared to the control group(P<0.05).Compared to the incidence of nursing risk events,the observation group(6.52%)was significantly lower than the control group(30.43%),and there was a significant difference between the two groups(P<0.05).The observation group had significantly higher satisfaction scores for nursing skills,health education,service attitude,and professionalism compared to the control group,indicating patient satisfaction with safety culture construction(P<0.05).Conclusion:Applying safety culture construction in nursing management of infectious disease areas has a preventive effect on nursing risk events and is beneficial for improving patients’risk cognition level. 展开更多
关键词 Safety culture construction Infectious diseases Ward nursing Nursing management
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Influence of Car Park Proximity on Air Pollutant Concentrations at a Level 5 Hospital Outpatient Ward
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作者 Zolani Ndlovu Meshack Hawi +1 位作者 Hiram Ndiritu James Kimotho 《Computational Water, Energy, and Environmental Engineering》 2025年第1期37-60,共24页
Air quality is a critical factor in maintaining health and well-being, influencing both current conditions and future outcomes. Hospitals are one of the sensitive areas of our society, for they are built as sanctuarie... Air quality is a critical factor in maintaining health and well-being, influencing both current conditions and future outcomes. Hospitals are one of the sensitive areas of our society, for they are built as sanctuaries for treatment and recovery, making the quality of paramount importance. This study investigates the impact of traffic-related emissions on indoor air quality within a Level 5 Hospital outpatient ward. Measurements were taken over five consecutive days, revealing that while CO2 levels generally remained within safe limits, there were instances where concentrations exceeded 3000 ppm, categorizing them as “Hazardous.” Notably, particulate matter (PM2.5 and PM10) levels fluctuated significantly, with peak concentrations observed during working hours correlating with increased vehicle activity. The data indicated that PM2.5 levels reached as high as 75 µg/m3, with 91.68% of recorded values exceeding the World Health Organization’s (WHO) and Environmental Protection Agency 24-hour mean threshold of 25 µg/m3. Similarly, PM10 concentrations peaked at 120 µg/m3, with 61.19% of values surpassing the WHO threshold of 50 µg/m3, both of which pose serious health risks, particularly to vulnerable populations such as pregnant women, infants, and the elderly. Additionally, the study highlighted the critical role of wind direction in pollutant dispersion, with specific patterns contributing to elevated indoor concentrations. These findings underscore the urgent need for targeted interventions and proactive air quality management strategies in healthcare facilities, including the strategic design of hospital wards away from primary emission sources and the promotion of electric vehicle use to mitigate traffic-related emissions. 展开更多
关键词 Air Quality Hospital Wards Vehicle Emissions Particulate Matter Wind Direction Scalar dispersion Carpark and Driveway
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Evaluating the impact of virtual reality on reducing restrictive practices in psychiatric wards
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作者 Akpoveta Eguono Deborah Uchenna Esther Okpete Haewon Byeon 《World Journal of Psychiatry》 2025年第2期268-273,共6页
This manuscript critically evaluates the randomized controlled trial(RCT)conducted by Phiri et al,which assessed the effectiveness of virtual reality(VR)training for psychiatric staff in reducing restrictive practices... This manuscript critically evaluates the randomized controlled trial(RCT)conducted by Phiri et al,which assessed the effectiveness of virtual reality(VR)training for psychiatric staff in reducing restrictive practices(RPs).Specifically,this RCT investigated the impact of VR on the handling of aggressive patients by psychiatric staff compared to traditional training methods.Despite significant reductions in perceived discrimination in the VR group,there were no major improvements in self-efficacy or anxiety levels.The system usability scale rated the VR platform highly,but it did not consistently outperform traditional training methods.Indeed,the study shows the potential for VR to reduce RPs,although fluctuations in RP rates suggest that external factors,such as staff turnover,influenced the outcomes.This manuscript evaluates the study’s methodology,results,and broader implications for mental health training.Additionally,it highlights the need for more comprehensive research to establish VR as a standard tool for psychiatric staff education,focusing on patient care outcomes and real-world applicability.Finally,this study explores future research di-rections,technological improvements,and the potential impact of policies that could enhance the integration of VR in clinical training. 展开更多
关键词 Virtual reality Restrictive practices Psychiatric wards De-escalation techniques Staff training Generalized anxiety disorder System usability scale Burnout prevention
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Jerry W.Ward,Jr.:A Personal Critique
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作者 John Zheng 《外国语文研究》 2025年第2期18-30,共13页
Jerry W.Ward,Jr.(1943-2025)is a renowned African American scholar and poet.This article presents a critique of Dr.Ward by remembering him as a literary scholar and critic,educator,mentor,and cultural and academic amba... Jerry W.Ward,Jr.(1943-2025)is a renowned African American scholar and poet.This article presents a critique of Dr.Ward by remembering him as a literary scholar and critic,educator,mentor,and cultural and academic ambassador to China and the world.It reveals the uniqueness in Dr.Ward’s critical thinking about African American culture,tradition and history,his importance as an internationally known scholar,his originality in his poetic art,and the value of his legacy for African American literature and its scholarship. 展开更多
关键词 Jerry W.Ward Jr. African American literature remembrance critique
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基于Ward系统聚类的中国农用地整治实施状况分析 被引量:38
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作者 项晓敏 金晓斌 +2 位作者 杜心栋 孙伟 周寅康 《农业工程学报》 EI CAS CSCD 北大核心 2015年第6期257-265,共9页
为科学分析当前中国农用地整治的实施特征和空间格局特点,厘清实施状态与规划目标的协调状态,该文基于土地整治项目管理信息,以县域为研究单元,通过整治强度、整治潜力和整治难度3项指标,采用Ward系统聚类法,对2006-2012年中国农用地整... 为科学分析当前中国农用地整治的实施特征和空间格局特点,厘清实施状态与规划目标的协调状态,该文基于土地整治项目管理信息,以县域为研究单元,通过整治强度、整治潜力和整治难度3项指标,采用Ward系统聚类法,对2006-2012年中国农用地整治实施状况进行综合分区,并结合既定的规划目标,对实施状态进行了定量分析,得出以下结论:1)高整治强度区主要位于华北平原、三江平原、长江三角洲等传统农区;高整治潜力区主要位于青甘农牧区、黄土高原区等半湿润半干旱地区;高整治难度区主要位于秦巴山地和云贵高原等地形较为复杂的地区。2)研究期内中国农用地整治实施状态可划分为"中高-低-中"(Ⅰ类)、"中-中低-中"(Ⅱ类)、"中高-中高-中高"(Ⅲ类)、"低-中-高"(Ⅳ类)和"高-中低-中"(Ⅴ类)等5种类型,其中以Ⅲ类最为集中,Ⅰ类和Ⅱ类次之,Ⅳ类、Ⅴ类数量较少且分布零散。3)从实施状态与整治规划的协调性看,实施现状与规划确定的农用地整治重点区域、高标准基本农田建设示范县,以及基本农田整治重大工程等重点任务,均存在一定偏差;从与表征经济发展、粮食生产、土地整治活动的分区对比来看,区域差异不甚明显,整治重点尚不突出。该研究成果可为中国土地整治规划评价和宏观制度设计提供参考。 展开更多
关键词 土地利用 整治 规划 农用地 实施状态 协调性 Ward系统聚类
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基于BP模型和Ward法的北京市平谷区乡村地域功能评价与分区 被引量:55
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作者 唐林楠 刘玉 +1 位作者 潘瑜春 任艳敏 《地理科学》 CSCD 北大核心 2016年第10期1514-1521,共8页
构建乡村地域功能评价指标体系,借助BP神经网络模型揭示平谷区"生产-生活-生态"功能分异特征;运用Ward法划分功能区,服务于平谷区乡村转型发展和功能区布局。结果表明:1在多项功能综合作用下,平谷区基本形成了"平原地区... 构建乡村地域功能评价指标体系,借助BP神经网络模型揭示平谷区"生产-生活-生态"功能分异特征;运用Ward法划分功能区,服务于平谷区乡村转型发展和功能区布局。结果表明:1在多项功能综合作用下,平谷区基本形成了"平原地区生产功能较强、镇中心及周边村域生活功能明显、山地区以生态功能为主"的功能分布格局。2基于评价结果和空间属性,平谷区划分为西部平原生产区、东部山地生态生产区、中部平原城市生活区、中部近郊平原生活区、东部丘陵生态生活区和北部山地生态区。其中,西部平原生产区、中部平原城市生活区、北部山地生态区是平谷三生空间功能发展的优势区域,分布相对集中。按照"强功能重优化、中等功能重提升、弱功能重改善"的原则提升乡村地域功能,促进地区均衡发展。 展开更多
关键词 乡村地域功能 评价 BP模型 Ward法 平谷区
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中亚热带天然阔叶林林层划分新方法-最大受光面法 被引量:28
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作者 庄崇洋 黄清麟 +2 位作者 马志波 郑群瑞 王宏 《林业科学》 EI CAS CSCD 北大核心 2017年第3期1-11,共11页
【目的】依据林木树冠是否接受到垂直光照和林木树冠接受到垂直光照的程度提出林层划分新方法——最大受光面法,为揭示中亚热带天然阔叶林垂直结构的自然分异规律提供新方法。【方法】在典型中亚热带天然阔叶林中,采用最大受光面法将林... 【目的】依据林木树冠是否接受到垂直光照和林木树冠接受到垂直光照的程度提出林层划分新方法——最大受光面法,为揭示中亚热带天然阔叶林垂直结构的自然分异规律提供新方法。【方法】在典型中亚热带天然阔叶林中,采用最大受光面法将林分划分为受光层和非受光层;在受光层中,以林木树高为聚类因子采用离差平方和法(ward法)对受光层进一步分层。【结果】通过最大受光面法将5块典型中亚热带天然阔叶林标准地划分为受光层Ⅰ和非受光层Ⅱ,其中受光层包括Ⅰ_1和Ⅰ_2亚层;最大受光面法林层划分结果显示,5块标准地的受光层和非受光层的分界面高度(即第Ⅰ,Ⅱ层分界面高度)分别为17.0,16.5,17.0,17.0和16.0 m;Ⅰ_1和Ⅰ_2亚层的分界面高度分别为25.0,27.0,25.0,22.9和25.0 m;划分林层后,Ⅰ_1,Ⅰ_2和Ⅱ层的每公顷蓄积量,相邻的Ⅰ_1,Ⅰ_2和Ⅱ层间的高差和Ⅰ_1,Ⅰ_2,Ⅱ层平均胸径均符足林层划分国家标准(GBT 26424—2010)。【结论】CVPA-H曲线的变化规律证实了最大受光面的存在,在野外只需判断林木树冠是否接受到垂直光照和林木树冠是否明显突出(即接受到垂直光照的程度)即可实现林层划分,无需测量每株林木树高,野外操作简单易行;林层划分结果与剖面图判断结果的对比和各层测树因子都符合林层划分国家标准(GBT 26424—2010)等,验证了最大受光面法划分林层的科学性;最大受光面法能较好地反映中亚热带天然阔叶林垂直结构的自然分异规律,该方法依据林木树冠是否能接受到垂直光照和接受到垂直光照的程度进行林层划分,体现了林木对垂直光照和空间资源竞争的结果,具有一定的生物学意义。 展开更多
关键词 中亚热带 天然阔叶林 林层划分 最大受光面 ward法聚类
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中国住宅出让地价发育特征及其影响因素分析 被引量:17
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作者 韩娟 金晓斌 +3 位作者 张志宏 孙伟 徐心茹 周寅康 《地理科学》 CSSCI CSCD 北大核心 2017年第4期573-584,共12页
基于中国土地市场网2009~2013年招、拍、挂出让的住宅用地数据,以县级行政区域作为研究单元,建立区域住宅地价综合模型,选取地价水平、地价增长率和交易宗数作为评价指标,采用Ward系统聚类法,综合分析了中国住宅出让地价的发育特征,利... 基于中国土地市场网2009~2013年招、拍、挂出让的住宅用地数据,以县级行政区域作为研究单元,建立区域住宅地价综合模型,选取地价水平、地价增长率和交易宗数作为评价指标,采用Ward系统聚类法,综合分析了中国住宅出让地价的发育特征,利用多分类Logistic回归模型探索了各类地价发育形态的潜在影响因素。结果表明:1研究期内中国住宅出让地价总体呈现东高西低、沿海高于内陆、城市群带动周边区域发展、城市群内部围绕中心城市增长等空间格局特征;中西部地价高增长的单元多于东部,西北、东北中南部、四川盆地、河西走廊以及长江中下游地区是地价高增长的聚集区;住宅市场活跃度呈阶梯状变化,活跃度较高的地区主要分布在山东半岛、长三角、长江中游、辽宁中部、哈尔滨、成渝、滇中、呼包鄂等城市群。2根据综合特征,中国住宅出让地价空间发育可分为成熟稳健型、发展完善型、成长发展型、萌芽起步型和成长受阻型5类,相邻发育形态在空间关系上表现出互为邻里的特征。3各类发育区的主要影响因素差异显著。区位条件、居民收入和财政收入是地价发育成熟度的主要影响因素;人均GDP、国土开发度提升将促进地价形态发育程度;而人口吸引力不足、基础设施建设相对滞后等将导致地价形态发育受阻。 展开更多
关键词 住宅出让地价 发育形态 Ward聚类 LOGISTIC回归 县域
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考虑灵敏度一致性的外网静态等值新理论研究 被引量:18
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作者 余娟 张勉 +2 位作者 朱柳 颜伟 赵霞 《中国电机工程学报》 EI CSCD 北大核心 2013年第10期64-70,17,共7页
提出一种新的外网静态等值理论,该理论不仅可以保证等值前后系统潮流状态的一致性,还能保证如下两类灵敏度关系在等值前后的一致性:非发电机节点电压与发电机节点电压之间的灵敏度关系、非发电机节点电压与非发电机节点注入电流之间的... 提出一种新的外网静态等值理论,该理论不仅可以保证等值前后系统潮流状态的一致性,还能保证如下两类灵敏度关系在等值前后的一致性:非发电机节点电压与发电机节点电压之间的灵敏度关系、非发电机节点电压与非发电机节点注入电流之间的灵敏度关系。已有的外网静态等值方法往往只能保证潮流状态的一致性,所以文中所提等值理论更为严格,从而能获得更高的外网等值精度。基于节点电压方程,以潮流状态和两类灵敏度关系在等值前后应保持一致为前提条件,结合Ward等值理论推导所提外网静态等值网络及其参数。IEEE39节点系统和广东电网的仿真结果表明所提理论的准确性和有效性。 展开更多
关键词 外网静态等值 灵敏度 WARD等值 静态安全分析
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谐波对多馈入直流输电系统换相失败的影响 被引量:28
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作者 王玲 文俊 +2 位作者 李亚男 刘婷婷 赵国鹏 《电工技术学报》 EI CSCD 北大核心 2017年第3期27-34,共8页
从换相失败的产生机理出发,分析出谐波引起换相失败的根本原因,提出了电压时间面积的分析方法,同时定义并计算出了5、7、11、13次主导谐波分别导致换相失败时的换相失败临界偏移角和临界比例系数。以实际上海多馈入直流输电系统为例,通... 从换相失败的产生机理出发,分析出谐波引起换相失败的根本原因,提出了电压时间面积的分析方法,同时定义并计算出了5、7、11、13次主导谐波分别导致换相失败时的换相失败临界偏移角和临界比例系数。以实际上海多馈入直流输电系统为例,通过电网等效谐波模型及Ward等值算法,利用Matlab计算出背景谐波造成的直流接入点电压偏移量,给出各谐波引起换相失败的临界条件并进行了仿真验证。最后提出了直流工程中防止谐波引起换相失败应满足的条件。所得结论对于交直流电网的规划与运行有实际参考作用。 展开更多
关键词 多馈入直流输电系统 谐波干扰 关断角 换相失败临界比例系数 WARD等值
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电力系统电磁暂态仿真外部系统等值方法综述 被引量:22
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作者 林济铿 闫贻鹏 +1 位作者 刘涛 郑卫洪 《电力系统自动化》 EI CSCD 北大核心 2012年第11期108-115,共8页
对实际电力系统进行电磁暂态仿真,往往耗时很长。如何有效地对外部系统进行等值以减小仿真系统的规模,长期以来是电磁暂态仿真研究领域中的一个重要课题。对该领域迄今为止主要外部系统等值方法进行了分类,给出了各类方法的基本过程,分... 对实际电力系统进行电磁暂态仿真,往往耗时很长。如何有效地对外部系统进行等值以减小仿真系统的规模,长期以来是电磁暂态仿真研究领域中的一个重要课题。对该领域迄今为止主要外部系统等值方法进行了分类,给出了各类方法的基本过程,分析了其优缺点;并对该领域今后的发展趋势及关键问题的突破作了展望。 展开更多
关键词 电力系统 电磁暂态仿真 外部系统等值 WARD等值
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甘草化学成分快速定性分析与化学模式识别研究 被引量:33
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作者 孙立丽 游广娇 +2 位作者 任晓亮 王萌 邓雁如 《中华中医药杂志》 CAS CSCD 北大核心 2018年第5期2074-2079,共6页
目的:采用超高效液相色谱-串联四极杆飞行时间质谱(UPLC-Q-TOF-MSE)建立甘草化学成分的快速定性分析方法,并采用超高效相色谱(UPLC)指纹图谱与化学模式识别结合进而分析72批次甘草间化学成分的差异性,为甘草的质量控制与评价提供实验依... 目的:采用超高效液相色谱-串联四极杆飞行时间质谱(UPLC-Q-TOF-MSE)建立甘草化学成分的快速定性分析方法,并采用超高效相色谱(UPLC)指纹图谱与化学模式识别结合进而分析72批次甘草间化学成分的差异性,为甘草的质量控制与评价提供实验依据。方法:运用时间依赖型MSE扫描方式采集甘草样品的质谱数据,快速鉴定甘草的主要化学成分,并采用Ward’s Method对UPLC指纹图谱数据进行探索性数据分析,获取分类信息,最后采用对偶传播人工神经网络分析不同分类组别的化学成分差异。结果:共鉴定了57个化合物,Ward’s Method分析将72批甘草样本区分为4组,利用对偶传播人工神经网络获取了甘草不同组别间的显著性差异成分。结论:本方法可以快速、全面实现甘草化学成分的定性分析,比较甘草间的化学成分差异性,为甘草质量等级标准的建立提供了参考依据。 展开更多
关键词 甘草 UPLC-Q-TOF-MSE 化学模式识别 Ward’s METHOD 对偶传播人工神经网络
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