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Chinese Expert Consensus on the Definitions of Palliative Care and Hospice Care(2025) 被引量:2
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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》 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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Classification of forest vegetation with the application of iterative reallocation and model-based clustering
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作者 Naghmeh Pakgohar Javad Eshaghi Rad +4 位作者 Hossein Gholami Ahmad Alijanpour David W.Roberts Attila Lengyel Enrico Feoli 《Journal of Forestry Research》 2025年第5期103-112,共10页
Numerous clustering algorithms are valuable in pattern recognition in forest vegetation,with new ones continually being proposed.While some are well-known,others are underutilized in vegetation science.This study comp... Numerous clustering algorithms are valuable in pattern recognition in forest vegetation,with new ones continually being proposed.While some are well-known,others are underutilized in vegetation science.This study compares the performance of practical iterative reallocation algorithms with model-based clustering algorithms.The data is from forest vegetation in Virginia(United States),the Hyrcanian Forest(Asia),and European beech forests.Practical iterative reallocation algorithms were applied as non-hierarchical methods and Finite Gaussian mixture modeling was used as a model-based clustering method.Due to limitations on dimensionality in model-based clustering,principal coordinates analysis was employed to reduce the dataset’s dimensions.A log transformation was applied to achieve a normal distribution for the pseudo-species data before calculating the Bray-Curtis dissimilarity.The findings indicate that the reallocation of misclassified objects based on silhouette width(OPTSIL)with Flexible-β(-0.25)had the highest mean among the tested clustering algorithms with Silhouette width 1(REMOS1)with Flexible-β(-0.25)second.However,model-based clustering performed poorly.Based on these results,it is recommended using OPTSIL with Flexible-β(-0.25)and REMOS1 with Flexible-β(-0.25)for forest vegetation classification instead of model-based clustering particularly for heterogeneous datasets common in forest vegetation community data. 展开更多
关键词 CLASSIFICATION Heuristic clustering Finite mixture Forest ecosystems model-based clustering
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Evaluating fever of unknown origin definitions in a tertiary care setting:Implications for diagnostic criteria revision
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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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Model-Based System Multidisciplinary Design Optimization for Preliminary Design of a Blended Wing-Body Underwater Glider
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作者 WANG Zhi-long LI Jing-lu +3 位作者 WANG Peng DONG Hua-chao WANG Xin-jing WEN Zhi-wen 《China Ocean Engineering》 2025年第4期755-767,共13页
Unlike traditional propeller-driven underwater vehicles,blended-wing-body underwater gliders(BWBUGs)achieve zigzag gliding through periodic adjustments of their net buoyancy,enhancing their cruising capabilities while... Unlike traditional propeller-driven underwater vehicles,blended-wing-body underwater gliders(BWBUGs)achieve zigzag gliding through periodic adjustments of their net buoyancy,enhancing their cruising capabilities while mini-mizing energy consumption.However,enhancing gliding performance is challenging due to the complex system design and limited design experience.To address this challenge,this paper introduces a model-based,multidisciplinary system design optimization method for BWBUGs at the conceptual design stage.First,a model-based,multidisciplinary co-simulation design framework is established to evaluate both system-level and disciplinary indices of BWBUG performance.A data-driven,many-objective multidisciplinary optimization is subsequently employed to explore the design space,yielding 32 Pareto optimal solutions.Finally,a model-based physical system simulation,which represents the design with the largest hyper-volume contribution among the 32 final designs,is established.Its gliding perfor-mance,validated by component behavior,lays the groundwork for constructing the entire system’s digital prototype.In conclusion,this model-based,multidisciplinary design optimization method effectively generates design schemes for innovative underwater vehicles,facilitating the development of digital prototypes. 展开更多
关键词 model-based design multidisciplinary design optimization data-driven optimization blended-wingbody underwater glider(BWBUG) physical system simulation
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Rethinking drought definition and classification
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作者 Wen Wang Hao Wang 《Water Science and Engineering》 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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Nexus of certain model-based estimators in remote sensing forest inventory 被引量:1
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作者 Yan Zheng Zhengyang Hou +6 位作者 Goran Ståhl Ronald EMcRoberts Weisheng Zeng Erik Næsset Terje Gobakken Bo Li Qing Xu 《Forest Ecosystems》 CSCD 2024年第6期921-930,共10页
Remote sensing(RS)facilitates forest inventory across a wide range of variables required by the UNFCCC as well as by other agreements and processes.The Conventional model-based(CMB)estimator supports wall-to-wall RS d... Remote sensing(RS)facilitates forest inventory across a wide range of variables required by the UNFCCC as well as by other agreements and processes.The Conventional model-based(CMB)estimator supports wall-to-wall RS data,while Hybrid estimators support surveys where RS data are available as a sample.However,the connection between these two types of monitoring procedures has been unclear,hindering the reconciliation of wall-to-wall and non-wall-to-wall use of RS data in practical applications and thus potentially impeding cost-efficient deployment of high-end sensing instruments for large area monitoring.Consequently,our objectives are to(1)shed further light on the connections between different types of Hybrid estimators,and between CMB and Hybrid estimators,through mathematical analyses and Monte Carlo simulations;and(2)compare the effects and explore the tradeoffs related to the RS sampling design,coverage rate,and cluster size on estimation precision.Primary findings are threefold:(1)the CMB estimator represents a special case of Hybrid estimators,signifying that wallto-wall RS data is a particular instance of sample-based RS data;(2)the precision of estimators in forest inventory can be greater for stratified non-wall-to-wall RS data compared to wall-to-wall RS data;(3)otherwise costprohibitive sensing,such as LiDAR and UAV,can support large scale monitoring through collecting RS data as a sample.These conclusions may reconcile different perspectives regarding choice of RS instruments,data acquisition,and cost for continuous observations,particularly in the context of surveys aiming at providing data for mitigating climate change. 展开更多
关键词 model-based inference Sampling Sample size Non-wall-to-wall Forest inventory
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Improved reservoir characterization by means of supervised machine learning and model-based seismic impedance inversion in the Penobscot field,Scotian Basin
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作者 Satya Narayan Soumyashree Debasis Sahoo +2 位作者 Soumitra Kar Sanjit Kumar Pal Subhra Kangsabanik 《Energy Geoscience》 EI 2024年第2期183-201,共19页
The present research work attempted to delineate and characterize the reservoir facies from the Dawson Canyon Formation in the Penobscot field,Scotian Basin.An integrated study of instantaneous frequency,P-impedance,v... The present research work attempted to delineate and characterize the reservoir facies from the Dawson Canyon Formation in the Penobscot field,Scotian Basin.An integrated study of instantaneous frequency,P-impedance,volume of clay and neutron-porosity attributes,and structural framework was done to unravel the Late Cretaceous depositional system and reservoir facies distribution patterns within the study area.Fault strikes were found in the EW and NEE-SWW directions indicating the dominant course of tectonic activities during the Late Cretaceous period in the region.P-impedance was estimated using model-based seismic inversion.Petrophysical properties such as the neutron porosity(NPHI)and volume of clay(VCL)were estimated using the multilayer perceptron neural network with high accuracy.Comparatively,a combination of low instantaneous frequency(15-30 Hz),moderate to high impedance(7000-9500 gm/cc*m/s),low neutron porosity(27%-40%)and low volume of clay(40%-60%),suggests fair-to-good sandstone development in the Dawson Canyon Formation.After calibration with the welllog data,it is found that further lowering in these attribute responses signifies the clean sandstone facies possibly containing hydrocarbons.The present study suggests that the shale lithofacies dominates the Late Cretaceous deposition(Dawson Canyon Formation)in the Penobscot field,Scotian Basin.Major faults and overlying shale facies provide structural and stratigraphic seals and act as a suitable hydrocarbon entrapment mechanism in the Dawson Canyon Formation's reservoirs.The present research advocates the integrated analysis of multi-attributes estimated using different methods to minimize the risk involved in hydrocarbon exploration. 展开更多
关键词 Reservoir characterization model-based inversion Multilayer perceptron(MLP) IMPEDANCE Petrophysical properties Scotian Basin
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Redefinition of the Global Stratotype Section and Point(GSSP)and new Standard Auxiliary Boundary Stratotype(SABS)for the base of Wuchiapingian Stage(Lopingian Series,Permian)in South China 被引量:2
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作者 Shu-zhong Shen Dong-xun Yuan +23 位作者 Yi-chun Zhang Charles M.Henderson Quan-feng Zheng Hua Zhang Min Zhang Yu Dai Hai-peng Xu Wen-qian Wang Qian Li Yue Wang Xiang-dong Wang Lin Mu Jahandar Ramezani Douglas H.Erwin Lucia Angiolini Fei-fei Zhang Zhang-shuai Hou Jun Chen Xi-yang Zhang Shu-han Zhang Qiong Wu Yong-xin Pan Michael Stephenson Shi-long Mei 《Episodes》 2024年第1期147-177,共31页
The Global Stratotype Section and Point(GSSP)of the base-Wuchiapingian Stage was formally ratified at the Penglaitan section in South China in 2005.However,the riverside GSSP section at Penglaitan and its auxiliary se... The Global Stratotype Section and Point(GSSP)of the base-Wuchiapingian Stage was formally ratified at the Penglaitan section in South China in 2005.However,the riverside GSSP section at Penglaitan and its auxiliary section at Tieqiao have been permanently flooded since 2020.We herein designate an excavated section at Penglaitan as the new GSSP and the Fengshan section as a new Standard Auxiliary Boundary Stratotype(SABS).In addition,we revised the original definition based on a detailed restudy of the conodont succession from the two sections.We define the GSSP of the base-Wuchiapingian by the First Appearance Datum(FAD)of Clarkina postbitteri within the lineage Jinogondolella granti→Clarkina postbitteri→C.dukouensis.It represents a major evolutionary turnover in conodonts from Jinogondolella to Clarkina and marks the end-Guadalupian extinction event.The U-Pb date of 259.51±0.21 Ma from the uppermost part of the Emeishan basalt is adopted for the GLB age.δ13Ccarb chemostratigraphy at the SABS exhibits several excursions between 3‰and 5‰across the GLB interval.Carbonate 87Sr/86Sr ratio is 0.707244 at the GLB.Remarkably,the SABS contains six normal and six reverse geomagnetic polarity zones in the uppermost Capitanian and three in the lowest Wuchiapingian. 展开更多
关键词 Wuchiapingian stage PERMIAN revised original definition standard auxiliary boundary stratotype global stratotype section point U Pb dating standard auxiliary boundary stratotype sabs
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Model-Based Systems Engineering Approach to Design a Human Settlement to Better Serve Displaced People
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作者 Anicet Adjahossou 《Open Journal of Applied Sciences》 2024年第4期865-880,共16页
The challenge of transitioning from temporary humanitarian settlements to more sustainable human settlements is due to a significant increase in the number of forcibly displaced people over recent decades, difficultie... The challenge of transitioning from temporary humanitarian settlements to more sustainable human settlements is due to a significant increase in the number of forcibly displaced people over recent decades, difficulties in providing social services that meet the required standards, and the prolongation of emergencies. Despite this challenging context, short-term considerations continue to guide their planning and management rather than more integrated, longer-term perspectives, thus preventing viable, sustainable development. Over the years, the design of humanitarian settlements has not been adapted to local contexts and perspectives, nor to the dynamics of urbanization and population growth and data. In addition, the current approach to temporary settlement harms the environment and can strain limited resources. Inefficient land use and ad hoc development models have compounded difficulties and generated new challenges. As a result, living conditions in settlements have deteriorated over the last few decades and continue to pose new challenges. The stakes are such that major shortcomings have emerged along the way, leading to disruption, budget overruns in a context marked by a steady decline in funding. However, some attempts have been made to shift towards more sustainable approaches, but these have mainly focused on vague, sector-oriented themes, failing to consider systematic and integration views. This study is a contribution in addressing these shortcomings by designing a model-driving solution, emphasizing an integrated system conceptualized as a system of systems. This paper proposes a new methodology for designing an integrated and sustainable human settlement model, based on Model-Based Systems Engineering and a Systems Modeling Language to provide valuable insights toward sustainable solutions for displaced populations aligning with the United Nations 2030 agenda for sustainable development. 展开更多
关键词 Humanitarian Settlement Human Settlement Sustainability Systems Engineering model-based Systems Engineering Systems Modeling Language
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Masseter Vestibular Evoked Myogenic Potentials in Individuals with definite Meniere’s Disease:An Exploratory Study
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作者 Saloni Gugle Anuj Kumar Neupane 《Journal of Otology》 2025年第3期149-156,共8页
Background:The masseter vestibular evoked myogenic potential(mVEMP) is a novel test that has been explored in various brainstem lesions. However, it has not yet been studied in individuals with definite Meniere's ... Background:The masseter vestibular evoked myogenic potential(mVEMP) is a novel test that has been explored in various brainstem lesions. However, it has not yet been studied in individuals with definite Meniere's disease. Therefore, the current study aimed to investigate m VEMP responses in individuals with definite Meniere's disease and compare them with those of a reference group.Method:The present study investigated narrowband Claus Elberling chirp-evoked m VEMP responses in 22 ears diagnosed with definite Meniere's disease and 22 ears with hearing sensitivity ≤ 15 dB HL across three stimulation frequencies.Results:m VEMP responses in participants with definite Meniere's disease varied from normal to reduced or absent across three octave frequencies. These individuals exhibited significantly reduced P11-N21 peak-to-peak amplitudes compared to those in the reference group. Although a frequency tuning shift toward 1000 Hz was observed, the inter-frequency amplitude ratio of m VEMP was not found to be a sensitive parameter for detecting individuals with definite Meniere's disease. Additionally, no association was found between the degree of hearing loss or the duration of the disease and m VEMP responses. Conclusion: Participants with definite Meniere's disease exhibited reduced P11-N21 amplitude and a tuning shift toward 1000 Hz. These findings suggest the involvement of the vestibulo-trigeminal reflex pathway in this condition. 展开更多
关键词 mVEMP definite Meniere's disease NB CE-chirp frequency tuning AMPLITUDE
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The Njiki’s Fundamental Theorem-Definition on Fractions in the Mathematical Set ℚ and by Extension in ℝ and ℂ, for the Purpose of Leading to the Construction of Some Algebraic Structures as Its Theoretical Applications and for the Practical Ones
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作者 Jean Claude Njiki 《American Journal of Computational Mathematics》 2024年第3期358-379,共22页
The purpose of the research in the NJIKI’s fundamental THEOREM-DEFINITION on fractions in the mathematical set ℚand by extension in ℝand ℂand in order to construct some algebraic structures is about the proved EXISTE... The purpose of the research in the NJIKI’s fundamental THEOREM-DEFINITION on fractions in the mathematical set ℚand by extension in ℝand ℂand in order to construct some algebraic structures is about the proved EXISTENCE and the DEFINITION by NJIKI of two INNOVATIVE, IMPORTANT and TEACHABLE operations of addition or additive operations, in ℚ, marked ⊕and +α,β, and taken as VECTORIAL, TRIANGULAR, of THREE or PROPORTIONAL operations and in order to make THEM not be different from the RATIONAL ONE, +, but to bring much more and new information on fractions, and, by extension in ℝand ℂ. And the very NJIKI’s fundamental THEOREM-DEFINITION having many APPLICATIONS in the everyday life of the HUMAN BEINGS and without talking about computer sciences, henceforth being supplied with very interesting new ALGORITHMS. And as for the work done in the research, it will be waiting for its extension to be done after publication and along with the research results concerned. 展开更多
关键词 Operations of Addition Additive Operations in Laws in THEOREM-definition External Multiplication
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西门子Definition双源CT罕见故障维修案例分析 被引量:7
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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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西门子64排SOMATOM Definition Flash双源CT机典型故障分析与处理 被引量:8
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作者 韦国文 《医疗卫生装备》 CAS 2017年第9期155-156,共2页
0引言 西门子64排SOMATOM Definition Flash双源CT机(简称"炫速双源CT机")是第二代双源CT,也是目前全球最尖端、最先进的大型医疗设备,它具有不受心率限制的心血管成像,可实现超越探测器宽度的大范围灌注,具备以"炫速扫描、锐影... 0引言 西门子64排SOMATOM Definition Flash双源CT机(简称"炫速双源CT机")是第二代双源CT,也是目前全球最尖端、最先进的大型医疗设备,它具有不受心率限制的心血管成像,可实现超越探测器宽度的大范围灌注,具备以"炫速扫描、锐影技术"为代表的超低剂量成像,负荷条件下的心肌灌注检查等特点。设备平时运行稳定,但由于各种客观因素的存在,各种故障的出现也难以避免。 展开更多
关键词 西门子64排SOMATOM definition Flash双源CT机 故障分析 故障排除
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Mathematical Definitions of Operators for Cartographic Generalization 被引量:2
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作者 王晓妮 张洁 《Geo-Spatial Information Science》 2003年第1期70-73,共4页
This paper puts forword 11 cartographic generalization operator models and introduces their mathematical definitions,and thus a precise mathematical form and quantitative description has been given to these formerly l... This paper puts forword 11 cartographic generalization operator models and introduces their mathematical definitions,and thus a precise mathematical form and quantitative description has been given to these formerly limited qualitative concepts.The meaning of mathematical definition of operators for cartographic generalization and the application prospect in computer_aided cartography (CAC) is stated.ract The Jurassic strata in Jingyan of Sichuan containing the Mamenchinsaurus fauna are dealt with and divided in this paper. The Mamenchisaurus fossils contained there are compared in morphological features and stratigraphically with other types of the genus on by one. The comprehensive analysis show that the Mamenchisaurus fauna of Jingyan appeared in the early Late Jurassic and is primitive in morphology. The results of the morphological identification and stratigraphical study agree with each other. Their evolutionary processes in different apoches of the Late Jurassic also made clear. Key words Jingyan, Sichuan, Mamenchisaurus Fauna, stratigraphy, evolution 展开更多
关键词 operators for cartographic generalization mathematical definition SELECTION SIMPLIFICATION STRESS
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A Feature Definition Hierarchy for Supporting Design Process
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作者 孙正兴 张福炎 蔡士杰 《Journal of Southeast University(English Edition)》 EI CAS 1999年第1期55-62,共8页
The adaptability of features definition to applications is an essential condition for implementing feature based design. This paper makes attempt to present a hierarchical definition structure of features. The propos... The adaptability of features definition to applications is an essential condition for implementing feature based design. This paper makes attempt to present a hierarchical definition structure of features. The proposed scheme divides feature definition into application level, form level and geometric level, and provides links between different levels with feature semantics interpretation and enhanced geometric face adjacent graph. respectively. The results not only enable feature definition to abate from the specific dependence and become more extensive, but also provide a theoretical foundation for establishing the concurrent feature based design process model. 展开更多
关键词 design process feature based modeling feature definition hierarchical construction
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A Definition Formalism of Machining Features for DFM
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作者 孙正兴 张福炎 《Journal of Southeast University(English Edition)》 EI CAS 1999年第1期49-54,共6页
Benefiting from advances in feature technology for design and manufacture can not be expected before a formal methodology is established. This paper makes attempt to establish a definition formalism of machining featu... Benefiting from advances in feature technology for design and manufacture can not be expected before a formal methodology is established. This paper makes attempt to establish a definition formalism of machining features in design for manufacturability from two aspects: formal definition and manufacturability analysis. Some definitions for machining feature based upon the selection and sequencing of material removal operations for component in accordance with the design geometry are presented and a framework of feature based design for manufacturability is outlined correspondingly. The proposed scheme contributes to several aspects of feature based CAD/CAM integration, especially to encourage potentially a more generic approach to the automation of design. 展开更多
关键词 design for manufacturability(DFM) feature technology machining feature definition formalism process planning
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西门子Definition AS 128层螺旋CT故障维修3例 被引量:12
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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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一种基于内容模型图的XML Schema Definition的提取方法 被引量:3
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作者 宁静 刘杰 叶丹 《计算机科学》 CSCD 北大核心 2010年第6期179-185,共7页
使用XML Schema能够对XML文档进行有效性验证以及对查询、转换等操作进行优化,但是实际应用中大量XML文档缺失关联的Schema。提出了一种根据XML文档自动提取对应的XML Schema Definition(XSD)的方法XSDInfer,先根据合并规则将XML解析过... 使用XML Schema能够对XML文档进行有效性验证以及对查询、转换等操作进行优化,但是实际应用中大量XML文档缺失关联的Schema。提出了一种根据XML文档自动提取对应的XML Schema Definition(XSD)的方法XSDInfer,先根据合并规则将XML解析过程中分析得到的模式信息记录在内容模型图中,再根据生成规则将其转化为内容模型表达式,进而得到XSD。XSDInfer能够在内存消耗比较少的情况下快速地处理超大规模、深度嵌套的XML文档,同时支持XSD的上下文相关的内容模型,提取出的XSD也具有更好的可读性。实验表明,与同类方法相比,XSDInfer具有更好的可扩展性和表达能力。 展开更多
关键词 XML XML SCHEMA definition 模式提取 内容模型
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西门子Definition AS术中CT两例硬件故障维修分析 被引量:4
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作者 孔康辉 赵东升 张龙 《中国医疗设备》 2022年第11期176-179,共4页
本文介绍了西门子Definition AS术中CT两例典型硬件故障。一例故障现象为停电导致扫描机架不上电,F1开关跳闸,复位后设备重启正常,随着停电次数的增多,F1开关复位困难。故障排除方法是更换工业继电器SIEMENS SIRIUS 3RS1800-2BP00。另... 本文介绍了西门子Definition AS术中CT两例典型硬件故障。一例故障现象为停电导致扫描机架不上电,F1开关跳闸,复位后设备重启正常,随着停电次数的增多,F1开关复位困难。故障排除方法是更换工业继电器SIEMENS SIRIUS 3RS1800-2BP00。另一例故障现象为扫描架显示屏呈灰色条纹状,进入故障日志查到216故障代码,故障现象描述故障点存在于XDC模块。故障排除方法是更换品牌为TDK-Lambda、型号为PH50S280-5的DC-DC模块。基于CT电路板的故障维修方法及其技术规律对两例硬件典型故障排查和修复、医疗电子设备维修技术水平有效提升提供借鉴价值。 展开更多
关键词 西门子definition AS XDC模块 DC-DC模块 反求电路原理图
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Model-based meta-analysis of pharmacokinetics of direct-acting antiviral agents,ledipasvir and sofosbuvir,in healthy subjects and chronic HCV patients 被引量:1
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作者 王鹤川 李良 +2 位作者 任宇鹏 周田彦 卢炜 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2015年第12期773-779,共7页
A tablet consisting of direct-acting antiviral agents,ledipasvir(a NS5 A protein inhibitor) and sofosbuvir(a NS5 B polymerase inhibitor),is the first fixed-dose preparation used in the antiviral therapy of hepatit... A tablet consisting of direct-acting antiviral agents,ledipasvir(a NS5 A protein inhibitor) and sofosbuvir(a NS5 B polymerase inhibitor),is the first fixed-dose preparation used in the antiviral therapy of hepatitis C.A model-based meta-analysis of ledipasvir and GS331007,the primary metabolite of sofosbuvir,enabled the integration of pharmacokinetic(PK) information from separate clinical trials and the quantitative characterization of the population pharmacokinetics of these two drugs.A systematic publication search was conducted for the clinical studies of ledipasvir and sofosbuvir.A total of 401 arm-level aggregate concentrations of GS331007 and 188 concentrations of ledipasvir were used for PK modeling.A two-compartment disposition model was used for both ledipasvir and GS331007.Zero-order absorption was applied for ledipasvir PK modeling,and a combined zero- and first-order absorption was used for the modeling of GS331007.Absorption lag was observed in concentration-time profiles of both ledipasvir and GS331007.To aid the development of direct-acting antiviral drugs,our established PK models provided a basis for the further PK-viral kinetic studies of ledipasvir and sofosbuvir. 展开更多
关键词 Ledipasvir Sofosbuvir GS331007 Population pharmacokinetic modeling Hepatitis C model-based meta-analysis
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