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Rethinking drought definition and classification 认领 引用 被引量：1
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作者 Wen Wang Hao Wang 《Water Science and Engineering》 EI CAS CSCD 2025年第2期125-128,共4页
Accurate drought assessment demands thoughtful consideration of drought definition first of all.Drought is commonly defined as a prolonged period of below-average precipitation leading to water shortages that impact e... Accurate drought assessment demands thoughtful consideration of drought definition first of all.Drought is commonly defined as a prolonged period of below-average precipitation leading to water shortages that impact ecosystems,agriculture,and human societies.However,meteorologists,hydrologists,and agronomists often use different criteria to define drought,depending on their specific focus areas.For example,hydrologists define drought according to water deficits in some components of the hydrological cycle(such as precipitation,soil moisture,river flow,and groundwater)or its impacts on the level of services provided to public water supply,irrigation,or hydropower demands(Tate and Gustard,2000).Differences in drought definitions may result in great uncertainties in drought assessment(Satoh et al.,2021).We cannot expect the existence of any workable generalized objective definition of drought(Lloyd-Hughes,2014). 展开更多
关键词 drought assessment river flow public water supply precipitation drought definition hydrological cycle drought classification soil moisture
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Chinese Expert Consensus on the Definitions of Palliative Care and Hospice Care(2025) 认领 引用 被引量：23
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作者 Chinese Expert Consensus Working Group on the Definition of Palliative Care Xiao-Hong Ning +3 位作者 Yan-Ru Guo Duan-Qi Liu Yuan Qin Yu-Mei Wang 《Chinese Medical Sciences Journal》 CAS CSCD 2025年第2期89-99,共11页
Background and Objective The development of modern palliative care in China began in the 1980s and is currently in an accelerating phase.However,inconsistencies in terminology and concepts have hindered policy-making,... Background and Objective The development of modern palliative care in China began in the 1980s and is currently in an accelerating phase.However,inconsistencies in terminology and concepts have hindered policy-making,clinical practice,and academic research.The Terminology of Clinical Medicine(2023 edition)has determined huan-he-yi-liao(缓和医疗)and an-ning-liao-hu(安宁疗护)as the formal terms of"palliative care"and"hospice care",respectively.To align with these terms,this study aims to establish expert consensus definitions tailored to the Chinese context.Methods We systematically retrieved and collected domestic and international literature and policy documents related to the definition of palliative care,then deconstructed and analyzed the relevant conceptual elements of these definitions.Core expert panel built the initial recommended definition upon the conceptual elements and consensus definition of palliative care by the International Association for Hospice and Palliative Care(IAHPC)through two rounds of online discussions.After nomination and selection,61 professionals in the field of palliative care in China were invited to participate in the consensus expert group.Two rounds of Delphi consultation were conducted among the consensus experts,who were asked to score their agreement using Likert scale to the items in the initial recommended definition and the definition statements of palliative care and hospice care.Agreement rate of over 80%was considered as reaching consensus for each items.The core expert panel revised the items and the statements of recommended definitions based on the results from Delphi surveys.The final recommended definitions were formulated after feedback from patient and public involvement(PPI)group members.Results The response rates for the first and second round of Delphi surveys were 83.6%and 100.0%,respectively.The agreement rates of the items and statements of the recommended definitions exceeded 90%.Accordingly,the definitions based on Chinese expert consensus are recommended.Palliative care is an active holistic approach aimed at patients of all ages suffering from life-threatening illness and their families and caregivers.It seeks to improve their quality of life by preventing,assessing,and relieving physical,psychological,social,and spiritual suffering.Hospice care is an integral part of palliative care,focusing on holistic care for patients at the end of life and their families and caregivers.Its goal is to help patients to maintain dignity and achieve a good death by alleviating physical,psychological,social,and spiritual distress without intentionally hastening or postponing death,meanwhile improve the quality of life for families and caregivers.Conclusions This study has established the Chinese expert consensus definitions of palliative care and hospice care in China,as well as the relationship between the two.The definitions highlight the holistic nature of palliative care,providing a foundation for discipline development,clinical practice,and public communication. 展开更多
关键词 palliative care hospice care China Delphi definition
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Evaluating fever of unknown origin definitions in a tertiary care setting:Implications for diagnostic criteria revision 认领 引用
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作者 Pathik Dhangar Prasan Kumar Panda +6 位作者 Ravi Kant Rohit Gupta Ruchi Dua Ashutosh Tiwari Sandeep Saini Kavita Khoiwal Yogesh Bahurupi 《World Journal of Experimental Medicine》 2025年第2期103-108,共6页
BACKGROUND Fever of unknown origin(FUO)remains a diagnostic challenge and was originally defined in 1961.Its classic criteria include fever≥38.3°C(≥101°F)on multiple occasions,fever lasting three weeks or ... BACKGROUND Fever of unknown origin(FUO)remains a diagnostic challenge and was originally defined in 1961.Its classic criteria include fever≥38.3°C(≥101°F)on multiple occasions,fever lasting three weeks or longer,and a diagnosis after one week of inpatient evaluation.However,these criteria may not fully encompass the varied clinical presentations seen in resource-limited settings such as India.The adaptation of FUO definitions to local healthcare contexts is crucial for enhancing diagnostic accuracy and optimizing patient outcomes.AIM To investigate the applicability of revised FUO criteria in a tertiary care setting in India.METHODS This longitudinal-exploratory study at All India Institute of Medical Sciences Rishikesh(January 2018–December 2022)analyzed 228 adult patients with fever≥99.1°F lasting over three days.Patients diagnosed within three days of admission were excluded.Data were collected retrospectively and prospectively using predefined FUO definitions based on durations of nondiagnosis(3-21 days,>21 days),temperature ranges(99.1°F-100.9°F,≥101°F),and hospitalization durations(3-7 days,>7 days).Descriptive statistics and comparative tests(Fisher's exact test,χ2 test)evaluated outcomes across definitions.RESULTS Among the proposed FUO definitions,Definition B(fever lasting 3-21 days,temperatures between 99.1°F-100.9°F,hospitalization>7 days)predominated(40.8%),while only 2.2%met the classical criteria.Notably,36.5%of Definition B patients remained undiagnosed after 7-10 days,despite 94%undergoing diagnostic workups within 21 days.Infection emerged as the leading etiology across definitions,without significant variation in outcomes or mortality during hospitalization(χ2=27.937,P=0.142).CONCLUSION Adapting FUO criteria to local contexts improves diagnostic accuracy and treatment.Definition B(40.8%prevalence)showed practical utility,with higher mortality in patients discharged on empirical'Anti-tuberculosis therapy'. 展开更多
关键词 Empirical therapy New definition Pyrexia of unknown origin Tuberculosis
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西门子SOMATOM Definition AS大孔径CT故障维修五例 认领 引用 被引量：1
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作者 刘学彦 徐辉煌 《医疗装备》 2025年第24期86-89,共4页
目前,精准放射治疗已成为提高肿瘤治疗效果的关键手段。但传统CT设备因孔径受限,难以满足肥胖患者、特殊体位固定装置或复杂解剖部位的扫描需求,导致放射治疗定位精度受限,进而影响患者的诊疗质量。西门子SOMATOM Definition AS大孔径C... 目前,精准放射治疗已成为提高肿瘤治疗效果的关键手段。但传统CT设备因孔径受限,难以满足肥胖患者、特殊体位固定装置或复杂解剖部位的扫描需求,导致放射治疗定位精度受限,进而影响患者的诊疗质量。西门子SOMATOM Definition AS大孔径CT采用64排128层陶瓷探测器,最薄扫描层厚为0.6 mm,Z轴宽度为3.84 cm,机架孔径为78 cm,最快转速为0.3 s/圈[1],最大扫描速度为20 cm/s。该设备可对从多个角度穿过受检者的X线开展光电转换、放大、滤噪、模数转换等信号处理工作,生成的源数据再经计算机后处理重建为清晰可见的灰阶图像,从而为临床诊断提供精确的影像结果。 展开更多
关键词 Definition AS CT 大孔径 故障分析 故障维修
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A note on the definition of fractional derivatives applied in rheology 认领 引用 被引量：1
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作者 Fan Yang Ke-Qin Zhu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第6期866-876,共11页
It is known that there exist obivious differences between the two most commonly used definitions of fractional derivatives-Riemann-Liouville(R-L)definition and Caputo definition.The multiple definitions of fractional ... It is known that there exist obivious differences between the two most commonly used definitions of fractional derivatives-Riemann-Liouville(R-L)definition and Caputo definition.The multiple definitions of fractional derivatives in fractional calculus have hindered the application of fractional calculus in rheology.In this paper,we clarify that the R-L definition and Caputo definition are both rheologically imperfect with the help of mechanical analogues of the fractional element model(Scott-Blair model).We also clarify that to make them perfect rheologically,the lower terminals of both definitions should be put to∞.We further prove that the R-L definition with lower terminal a→∞and the Caputo definition with lower terminal a→∞are equivalent in the differentiation of functions that are smooth enough and functions that have finite number of singular points.Thus we can define the fractional derivatives in rheology as the R-L derivatives with lower terminal a→∞(or,equivalently,the Caputo derivatives with lower terminal a→∞)not only for steady-state processes,but also for transient processes.Based on the above definition,the problems of composition rules of fractional operators and the initial conditions for fractional differential equations are discussed,respectively.As an example we study a fractional oscillator with Scott-Blair model and give an exact solution of this equation under given initial conditions. 展开更多
关键词 Fractional derivatives Rheology Riemann-Liouville definition Caputo definition
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On the definition of fractional derivatives in rheology 认领 引用 被引量：1
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作者 Fan Yang Ke-Qin Zhu 《Theoretical & Applied Mechanics Letters》 EI CAS 2011年第1期62-65,共4页
During the last two decades fractional calculus has been increasingly applied to physics,especially to rheology.It is well known that there are obivious differences between Riemann-Liouville(R-L)definition and Caputo ... During the last two decades fractional calculus has been increasingly applied to physics,especially to rheology.It is well known that there are obivious differences between Riemann-Liouville(R-L)definition and Caputo definition,which are the two most commonly used definitions of fractional derivatives.The multiple definitions of fractional derivatives have hindered the application of fractional calculus in rheology.In this paper,we clarify that the R-L definition and Caputo definition are both Theologically unreasonable with the help of the mechanical analogues of the fractional element model.We also find that to make them more reasonable Theologically,the lower terminals of both definitions should be put to—∞.We further prove that the R-L definition with lower terminal—∞and the Caputo definition with lower terminal—∞are equivalent in the differentiation of functions that are smooth enough and functions that have finite number of singular points.Thus we can define the fractional derivatives in rheology as the R-L derivatives with lower terminal—∞(or,equivalently,the Caputo derivatives with lower terminal—∞)not only for steady-state processes,but also for transient processes. 展开更多
关键词 fractional derivative Caputo definition Riemann-Liouville definition Scott-Blair model
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Improving sessile serrated adenoma detection rates with high definition colonoscopy:A retrospective study 认领 引用 被引量：3
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作者 Abhinav Sehgal Soorya Aggarwal +2 位作者 Rohan Mandaliya Thomas Loughney Mark C Mattar 《World Journal of Gastrointestinal Endoscopy》 2022年第4期226-234,共9页
BACKGROUND Sessile serrated adenomas(SSAs)are important premalignant lesions that are difficult to detect during colonoscopy due to poor definition,concealment by mucous caps,and flat appearance.High definition(HD)col... BACKGROUND Sessile serrated adenomas(SSAs)are important premalignant lesions that are difficult to detect during colonoscopy due to poor definition,concealment by mucous caps,and flat appearance.High definition(HD)colonoscopy may uniquely aid in the detection of these inconspicuous lesions compared to standard definition(SD)colonoscopes.In the absence of existing clinical guidelines to obligate the use of HD colonoscopy for colorectal cancer screening in average-risk patients,demonstrating the benefit of HD colonoscopy on SSA detection rate(SSADR)may help strengthen the evidence to recommend its use in all settings.AIM To evaluate the benefit of HD colonoscopy compared to SD colonoscopy on SSADR in average-risk patients undergoing screening colonoscopy.METHODS Data from screening colonoscopies for patients aged 50-76 years two years before and two years after the transition from SD colonoscopy to HD colonoscopy at our large,academic teaching center were collected.Patients with symptoms of colorectal disease,positive occult blood test,history of colon polyps,cancer,polyposis syndrome,inflammatory bowel disease or family history of colon cancer or polyps were excluded.Patients whose endoscopists did not perform colonoscopies both before and after scope definition change were also excluded.Differences in individual endoscopist SSADR,average SSADR,and overall SSADR with SD colonoscopy vs HD colonoscopy were also evaluated for significance.RESULTS A total of 3657 colonoscopies met eligibility criteria with 2012 colonoscopies from the SD colonoscopy period and 1645 colonoscopies from the HD colonoscopy period from a pool of 11 endoscopists.Statistically significant improvements of 2.30%in mean SSADR and 2.53%in overall SSADR were noted with HD colonoscopy(P=0.00028 and P=0.00849,respectively).On the individual level,three endoscopists experienced statistically significant benefit with HD colonoscopy(+5.74%,P=0.0056;+4.50%,P=0.0278;+4.84%,P=0.03486).CONCLUSION Our study suggests that HD colonoscopy statistically significantly improves sessile serrated adenoma detection rate in the screening of average risk patients during screening colonoscopy.By improving the detection and removal of these lesions,adoption of HD colonoscopy may reduce the significant premalignant burden of sessile serrated adenomas. 展开更多
关键词 Colonoscopy High definition Standard definition Sessile serrated adenoma Colorectal cancer screening
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Definition and classification system of glacial lake for inventory and hazards study 认领 引用 被引量：22
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作者 姚晓军 刘时银 +2 位作者 韩磊 孙美平 赵琳林 《Journal of Geographical Sciences》 SCIE CSCD 2018年第2期193-205,共13页
Glacial lakes are not only the important refresh water resources in alpine region, but also act as a trigger of many glacial hazards such as glacial lake outburst flood （GLOF） and debris flow. Therefore, glacial lak... Glacial lakes are not only the important refresh water resources in alpine region, but also act as a trigger of many glacial hazards such as glacial lake outburst flood （GLOF） and debris flow. Therefore, glacial lakes play an important role on the cryosphere, climate change and alpine hazards. In this paper, the issues of glacial lake were systematically discussed, then from the view of glacial lake inventory and glacial lake hazards study, the glacial lake was defined as natural water mainly supplied by modern glacial meltwater or formed in glacier moraine＇s depression. Furthermore, a complete classification system of glacial lake was proposed based on its formation mechanism, topographic feature and geographical position. Glacial lakes were classified as 6 classes and 8 subclasses, i.e., glacial erosion lake （including cirque lake, gla- cial valley lake and other glacial erosion lake）, moraine-dammed lake （including end mo- raine-dammed lake, lateral moraine-dammed lake and moraine thaw lake）, ice-blocked lake （including advancing glacier-blocked lake and other glacier-blocked lake）, supraglacial lake, subglacial lake and other glacial lake. Meanwhile, some corresponding features exhibiting on remote sensing image and quantitative indices for identifying different glacial lake types were proposed in order to build a universal and operational classification system of glacial lake. 展开更多
关键词 glacial lake glacier definition classification inventory hazard
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Consensus on the definition of colorectal anastomotic leakage: A modified Delphi study 认领 引用 被引量：12
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作者 Claire PM van Helsdingen Audrey CHM Jongen +2 位作者 Wouter J de Jonge Nicole D Bouvy Joep PM Derikx 《World Journal of Gastroenterology》 SCIE CAS 2020年第23期3293-3303,共11页
BACKGROUND Despite the emerging knowledge about colorectal anastomotic leakage(CAL)through the increasing number of clinical and experimental studies, there is no generally accepted definition of CAL. Because of the w... BACKGROUND Despite the emerging knowledge about colorectal anastomotic leakage(CAL)through the increasing number of clinical and experimental studies, there is no generally accepted definition of CAL. Because of the wide variety of definitions used in literature, comparison of study outcomes and quality of care is complicated.AIM To reach consensus on the definition of CAL using a modified Delphi method.METHODS The RAND/UCLA appropriateness method was used. The expert panel consisted of international colorectal surgeons and researchers who had published three or more articles about CAL. The consensus process consisted of two online distributed questionnaires and a third round with a recommendation. In the questionnaires participants were asked to rate the appropriateness of statements using a 1-9 Likert scale. Consensus was defined as a panel median between 1-3 or 7-9 without disagreement. In the final round a recommendation was formed regarding the definition of CAL and the expert panel was asked if they agreed or disagreed.RESULTSTwenty-three authors participated in the first round and twenty-one finished the second round. After two rounds consensus was reached on 37 items(80%) in nine different categories. The International Study Group of Rectal Cancer definition is the most frequently advised general definition by our panel. Consensus was reached regarding the clinical symptoms of CAL, which serum markers contributes to the suspicion of CAL, which radiological and perioperative findings should be considered as CAL, which grading system is appropriate and if there should be a range of postoperative days in the definition. Eventually, 19 experts completed all three rounds of which 16(84%) agreed with our final recommendations for the definition of CAL.CONCLUSION A consensus-based recommendation for the definition of CAL was formed using our modified Delphi method that can be widely incorporated in the field. 展开更多
关键词 Anastomotic leak Consensus Colorectal surgery Postoperative complication Morbidity Colorectal anastomosis Definition
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Gait Definition and Successive Gait-transition Method Based on Energy Consumption for a Quadruped 认领 引用 被引量：8
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作者 ZHAO Danpu XU Jing +2 位作者 WU Dan CHEN Ken LI Chengrong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第1期29-37,共9页
In nature, to realize the smooth motion for different speeds, the continuous gait transition is usually required for the quadrupeds. Thus, the gait simulation of quadrupeds is a requisite step to obtain the stable and... In nature, to realize the smooth motion for different speeds, the continuous gait transition is usually required for the quadrupeds. Thus, the gait simulation of quadrupeds is a requisite step to obtain the stable and energy-efficient gait for the walking machines. In this paper, the definitions of the two gait parameters, phasic difference and duty factor are presented, which can determine the gait of the quadrupeds. Then, several typical gaits of the quadrupeds are analyzed such that the seven standard gaits and corresponding parameters are summarized. Additionally, the variance law of the two parameters, which determine the relationship of gait transition, is analyzed. Furthermore, the quadruped gait derivative spectrum (QGDS) is proposed and the gait definition of the quadrupeds is presented. To minimize the power consumption, the choice criterion of gait, the optimal gait in terms of the motion speed, duty factory, and power consumption for the walking machines, is developed. Last, the continuous variance of the gait is implemented by the simulation of the gait transition from walk to trot, which evaluate the choice criterion and transition of gait. 展开更多
关键词 gait definition standard gaits quadruped gait-transition
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Definition of colorectal anastomotic leakage:A consensus survey among Dutch and Chinese colorectal surgeons 认领 引用 被引量：8
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作者 Stefanus J van Rooijen Audrey CHM Jongen +4 位作者 Zhou-qiao Wu Jia-fu Ji Gerrit D Slooter Rudi MH Roumen Nicole D Bouvy 《World Journal of Gastroenterology》 SCIE CAS 2017年第33期6172-6180,共9页
AIM To determine the level of consensus on the definition of colorectal anastomotic leakage(CAL)among Dutch and Chinese colorectal surgeons.METHODS Dutch and Chinese colorectal surgeons were asked to partake in an onl... AIM To determine the level of consensus on the definition of colorectal anastomotic leakage(CAL)among Dutch and Chinese colorectal surgeons.METHODS Dutch and Chinese colorectal surgeons were asked to partake in an online questionnaire.Consensus in the online questionnaire was defined as>80%agreement between respondents on various statements regarding a general definition of CAL,and regarding clinical and radiological diagnosis of the complication.RESULTS Fifty-nine Dutch and 202 Chinese dedicated colorectal surgeons participated in the online survey.Consensus was found on only one of the proposed elements of a general definition of CAL in both countries:‘extravasation of contrast medium after rectal enema on a CT scan'.Another two were found relevant according to Dutch surgeons:‘necrosis of the anastomosis found during reoperation',and‘a radiological collection treated with percutaneous drainage'.No consensus was found for all other proposed elements that may be included in a general definition.CONCLUSION There is no universally accepted definition of CAL in the Netherlands and China.Diagnosis of CAL based on clinical manifestations remains a point of discussion in both countries.Dutch surgeons are more likely to report‘subclinical'leaks as CAL,which partly explains the higher reported Dutch CAL rates. 展开更多
关键词 Colorectal anastomotic leakage Colorectal surgery Definition Complication
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Poorly cohesive cells gastric carcinoma including signet-ring cell cancer:Updated review of definition,classification and therapeutic management 认领 引用 被引量：10
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作者 Vincent Drubay Frederiek Nuytens +3 位作者 Florence Renaud Antoine Adenis Clarisse Eveno Guillaume Piessen 《World Journal of Gastrointestinal Oncology》 SCIE 2022年第8期1406-1428,共23页
While the incidence of gastric cancer(GC)in general has decreased worldwide in recent decades,the incidence of diffuse cancer historically comprising poorly cohesive cells-GC(PCC-GC)and including signet ring cell canc... While the incidence of gastric cancer(GC)in general has decreased worldwide in recent decades,the incidence of diffuse cancer historically comprising poorly cohesive cells-GC(PCC-GC)and including signet ring cell cancer is rising.Literature concerning PCC-GC is scarce and unclear,mostly due to a large variety of historically used definitions and classifications.Compared to other histological subtypes of GC,PCC-GC is nevertheless characterized by a distinct set of epidemiological,histological and clinical features which require a specific diagnostic and therapeutic approach.The aim of this review was to provide an update on the definition,classification and therapeutic strategies of PCC-GC.We focus on the updated histological definition of PCC-GC,along with its implications on future treatment strategies and study design.Also,specific considerations in the diagnostic management are discussed.Finally,the impact of some recent developments in the therapeutic management of GC in general such as the recently validated taxane-based regimens(5-Fluorouracil,leucovorin,oxaliplatin and docetaxel),the use of hyperthermic intraperitoneal chemotherapy as well as pressurized intraperitoneal aerosol chemotherapy and targeted therapy have been reviewed in depth for their relative importance for PCC-GC in particular. 展开更多
关键词 Poorly cohesive cells gastric carcinoma Review Definition Classification Therapeutic management
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Definitions of Pseudocapacitive Materials: A Brief Review 认领 引用 被引量：70
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作者 Yuqi Jiang Jinping Liu 《Energy & Environmental Materials》 SCIE EI CAS 2019年第1期30-37,共8页
Pseudocapacitive materials generally offer both high capacitance and high rate capability, which has stimulated great efforts in developing the materials system and related energy storage devices. In recent years, how... Pseudocapacitive materials generally offer both high capacitance and high rate capability, which has stimulated great efforts in developing the materials system and related energy storage devices. In recent years, however, with the extensive use of nanomaterials in batteries, fast redox kinetics comparable to pseudocapacitive have been achieved in many kinds of battery materials due to the much shortened ion diffusion lengths and highly exposed surface/interface as a result of nanosize effect. Consequently, the terms"pseudocapacitive materials" and "battery materials" are becoming more and more confusing. In this review, different opinions on the definition of pseudocapacitive materials and the evolution of the definitions as well as the resulting confusion will be firstly reviewed. Then, to accurately distinguish pseudocapacitive and battery materials, method with the consideration of both the electrochemical signatures(CVs and GCD) and quantitative kinetics analysis as a supplement is proposed. Finally, we end this review by discussing the possible device configurations of asymmetric supercapacitors and hybrid supercapacitors. The present review will help understanding the differences between pseudocapacitive materials and battery materials, and thus avoiding the definition confusion. 展开更多
关键词 definition electrochemical signatures pseudocapacitive material quantitative kinetics analysis
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Global climate change:impact of heat waves under different definitions on daily mortality in Wuhan,China 认领 引用 被引量：4
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作者 Yunquan Zhang Renjie Feng +4 位作者 Ran Wu Peirong Zhong Xiaodong Tan Kai Wu Lu Ma 《Global Health Research and Policy》 2017年第1期276-284,共9页
Background:There was no consistent definition for heat wave worldwide,while a limited number of studies have compared the mortality effect of heat wave as defined differently.This paper aimed to provide epidemiologica... Background:There was no consistent definition for heat wave worldwide,while a limited number of studies have compared the mortality effect of heat wave as defined differently.This paper aimed to provide epidemiological evidence for policy makers to determine the most appropriate definition for local heat wave warning systems.Methods:We developed 45 heat wave definitions(HWs)combining temperature indicators and temperature thresholds with durations.We then assessed the impact of heat waves under various definitions on non-accidental mortality in hot season(May-September)in Wuhan,China during 2003-2010.Results:Heat waves defined by HW14(daily mean temperature≥99.0th percentile and duration≥3 days)had the best predictive ability in assessing the mortality effects of heat wave with the relative risk of 1.63(95%CI:1.43,1.89)for total mortality.The group-specific mortality risk using official heat wave definition of Chinese Meteorological Administration was much smaller than that using HW14.We also found that women,and the elderly(age≥65)were more susceptible to heat wave effects which were stronger and longer lasting.Conclusion:These findings suggest that region specific heat wave definitions are crucial and necessary for developing efficient local heat warning systems and for providing evidence for policy makers to protect the vulnerable population. 展开更多
关键词 Climate change Temperature Heat wave Definition Mortality China
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西门子Definition AS 128层螺旋CT故障维修3例 认领 引用 被引量：15
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作者 肖吴进 孙小磊 +1 位作者 汪缨 张晖 《医疗卫生装备》 CAS 2022年第3期106-108,共3页
分析了西门子Definition AS 128层螺旋CT出现的检查床升降偶发中断、主机无法上传患者数据至工作站、检查床无法正常移动等故障原因,并给出了科学有效的解决方法,为工程技术人员维修此类故障提供了参考。
关键词 西门子Definition AS 128层螺旋CT 网络通信 故障维修
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西门子Definition双源CT罕见故障维修案例分析 认领 引用 被引量：9
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作者 孙小磊 张晖 汪缨 《医疗卫生装备》 CAS 2020年第11期106-108,共3页
简要介绍了CT稳定运行的重要性,详细分析了西门子Definition双源CT的滤过器运动电动机过流罕见故障并给出了具体的排除方法,保障了机器的正常运行,节省了维修成本,为同行维修类似故障提供了参考。
关键词 西门子Definition双源CT 滤过器 运动电动机 故障维修
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Circulation Indices of the Aleutian Low Pressure System:Definitions and Relationships to Climate Anomalies in the Northern Hemisphere 认领 引用 被引量：4
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作者 王盘兴 汪学良 +2 位作者 智海 王玉坤 孙晓娟 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2012年第5期1111-1118,共8页
In this study, a group of indices were defined regarding intensity （P）, area （S） and central position （λc, Фc） of the Aleutian low （AL） in the Northern Hemisphere in winter, using seasonal and monthly mean h... In this study, a group of indices were defined regarding intensity （P）, area （S） and central position （λc, Фc） of the Aleutian low （AL） in the Northern Hemisphere in winter, using seasonal and monthly mean height field at 1000-hPa. These indices were calculated over 60 winter seasons from 1948/1949 to 2007/2008 using reanalysis data. Climatic and anomalous characteristics of the AL were analyzed based on these indices and relationships between the AL, and general circulations were explored using correlations between indicesP, λc, and Pacific SST, as well as Northern Hemisphere temperature and precipitation. The main results are these： （1） AL is the strongest in January, when the center shifts to the south and west of its climatological position, and it is the weakest in December when the center shifts to the north and east. （2） AL intensity （P） is negatively correlated with its longitude （λc）： a deeper low occurs toward the east and a shallower low occurs toward the west. On a decadal scale, the AL has been persistently strong and has shifted eastward since the 1970s, but reversal signs have been observed in recent years. （3） The AL is stronger and is located toward the east during strong E1 Nifio winters and vice versa during strong La Nifia years; this tendency is particularly evident after 1975. The AL is also strongly correlated with SST in the North Pacific. It intensifies and moves eastward with negative SST anomalies, and it weakens and moves westward with positive SST anomalies. （4） Maps of significance correlation between AL intensity and Northern Hemisphere temperature and rainfall resemble the PNA teleconnection pattern in mid-latitudes in the North Pacific and across North America. The AL and the Mongolian High are two permanent atmospheric pressure systems adjacent to each other during boreal winter over the middle and high latitudes in the Northern Hemisphere, but their relationships with the E1 Nifio/La Nifia events and with temperature and precipitation in the Northern Hemisphere are significantly different. 展开更多
关键词 circulation indices the Aleutian Low definitions and relationships climate anomalies
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Considerations on the concept, definition, and diagnosis of amyotrophic lateral sclerosis 认领 引用 被引量：7
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作者 Ren-Shi Xu Min Yuan 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第9期1723-1729,共7页
The concept, definition, and diagnosis of amyotrophic lateral sclerosis(ALS) currently present some problems. This article systematically reviews the literature on the history, current concepts, definition, and diagno... The concept, definition, and diagnosis of amyotrophic lateral sclerosis(ALS) currently present some problems. This article systematically reviews the literature on the history, current concepts, definition, and diagnosis of ALS, and discloses the present problems based on the retrieved literature and the authors' clinical experience. The current concepts and definitions of ALS have not yet been unified or standardized in clinical practice, and are sometimes vague or inaccurate, which can cause difficulties for neurologists in the clinical treatment of ALS. The concept and definition of ALS need to be further ascertained, and the current diagnostic criteria for ALS require further development. The identification of effective and objective biomarkers may be a feasible method for the early and accurate diagnosis of ALS. Therefore, future research should focus on the identification of reliable biomarkers—especially neuroimaging biomarkers—through autopsy. Standardizing the concept and definition of ALS and formulating clear diagnostic criteria will largely avoid many uncertainties in the future clinical research and treatment of ALS, which will greatly benefit patients. 展开更多
关键词 amyotrophic lateral sclerosis clinical symptoms concept definition diagnosis familial amyotrophic lateral sclerosis motor neuron disease muscle atrophy
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Siemens Definition AS128 CT维修5例 认领 引用 被引量：4
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作者 仲建生 刘蕾 +2 位作者 闫瑾 陈奇兵 夏云成 《医疗卫生装备》 CAS 2023年第3期116-120,共5页
介绍了Siemens Definition AS128 CT的硬件构成,分析并总结了该设备在日常使用中出现的检查床水平移动后机架掉电、图像重建系统(image reconstruction system,IRS)计算机硬盘故障、开机时F1开关脱开、“Exam”按钮灰化等故障产生的原... 介绍了Siemens Definition AS128 CT的硬件构成,分析并总结了该设备在日常使用中出现的检查床水平移动后机架掉电、图像重建系统(image reconstruction system,IRS)计算机硬盘故障、开机时F1开关脱开、“Exam”按钮灰化等故障产生的原因及维修思路,为临床工程技术人员排除相似故障提供了参考。 展开更多
关键词 Siemens Definition AS128 CT 故障维修 故障排除
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Formal Definition of a User-Adaptive and Length-Optimal Routing Graph for Complex Indoor Environments 认领 引用 被引量：9
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作者 GOETZ Marcus ZIPF Alexander 《Geo-Spatial Information Science》 EI 2011年第2期119-128,共10页
Car routing solutions are omnipresent and solutions for pedestrians also exist.Furthermore,public or commercial buildings are getting bigger and the complexity of their internal structure has increased.Consequently,th... Car routing solutions are omnipresent and solutions for pedestrians also exist.Furthermore,public or commercial buildings are getting bigger and the complexity of their internal structure has increased.Consequently,the need for indoor routing solutions has emerged.Some prototypes are available,but they still lack semantically-enriched modelling (e.g.,access constraints,labels,etc.) and are not suitable for providing user-adaptive length-optimal routing in complex buildings.Previous approaches consider simple rooms,concave rooms,and corridors,but important characteristics such as distinct areas in huge rooms and solid obstacles inside rooms are not considered at all,although such details can increase navigation accuracy.By formally defining a weighted indoor routing graph,it is possible to create a detailed and user-adaptive model for route computation.The defined graph also contains semantic information such as room labels,door accessibility constraints,etc.Furthermore,one-way paths inside buildings are considered,as well as three-dimensional building parts,e.g.,elevators or stairways.A hierarchical structure is also possible with the presented graph model. 展开更多
关键词 3D indoor navigation 3D indoor routing city modelling formal definition routing graph buildings
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