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Characterization of the generalized permeability jail in tight reservoirs by analyzing relative-permeability curves and numerical simulation
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作者 Feng-Peng Lai Zhi-Ping Li +1 位作者 He-Xin Wei Wei Zhang 《Petroleum Science》 SCIE EI CSCD 2023年第5期2939-2950,共12页
This study comprehensively characterizes the boundary values of generalized permeability jail in tight reservoirs through relative-permeability curve analysis,numerical simulation,and economic evaluation.A total numbe... This study comprehensively characterizes the boundary values of generalized permeability jail in tight reservoirs through relative-permeability curve analysis,numerical simulation,and economic evaluation.A total number of 108 relative-permeability curves of rock samples from tight reservoirs were obtained,and the characteristics of relative-permeability curves were analyzed.The irreducible water saturation(Swi)mainly ranges from 20% to 70%,and the residual gas saturation(Sgr)ranges from 5% to 15% for 55% of the samples.The relative-permeability curves are categorized into six types(Category-Ⅰ to Ⅵ)by analyzing the following characteristics:The relative permeability of gas at Swi,the relative permeability of water at Sgr,and the relative permeability corresponding to the isotonic point.The relative permeability curves were normalized to facilitate numerical simulation and evaluate the impact of different types of curves on production performance.The results of simulation show significant difference in production performance for different types of relative-permeability curves:Category-Ⅰ corresponds to the case with best well performance,whereas Categories-Ⅴ and Ⅵ correspond to the cases with least production volume.The results of economic evaluation show a generalized permeability jail for Categories-Ⅳ,Ⅴ,and Ⅵ,and the permeability jail develops when the relative permeability of gas and water is below 0.06.This study further quantifies the range of micro-pore parameters corresponding to the generalized permeability jail for a tight sandstone reservoir. 展开更多
关键词 generalized permeability jail CHARACTERIZATION relative permeability curve Numerical simulation Pore structure
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A Relation of the Noncommutative Parameters in Generalized Noncommutative Phase Space
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作者 林冰生 衡太骅 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第11期22-24,共3页
We introduce the deformed boson operators which satisfy a deformed boson algebra in some special types of generalized noncommutative phase space. Based on the deformed boson algebra, we construct coherent state repres... We introduce the deformed boson operators which satisfy a deformed boson algebra in some special types of generalized noncommutative phase space. Based on the deformed boson algebra, we construct coherent state representations. We calculate the variances of the coordinate operators on the coherent states and investigate the corresponding Heisenberg uncertainty relations. It is found that there are some restriction relations of the noncommutative parameters in these special types of noncommutative phase space. 展开更多
关键词 of on is in HAVE A relation of the Noncommutative Parameters in generalized Noncommutative Phase Space
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On Relations for Moments of Generalized Order Statistics for Lindley–Weibull Distribution
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作者 Faten A.Momen khan Saman Hanif Shahbaz Muhammad Qaiser Shahbaz 《Computer Systems Science & Engineering》 SCIE EI 2022年第4期197-208,共12页
Moments of generalized order statistics appear in several areas of science and engineering.These moments are useful in studying properties of the random variables which are arranged in increasing order of importance,f... Moments of generalized order statistics appear in several areas of science and engineering.These moments are useful in studying properties of the random variables which are arranged in increasing order of importance,for example,time to failure of a computer system.The computation of these moments is sometimes very tedious and hence some algorithms are required.One algorithm is to use a recursive method of computation of these moments and is very useful as it provides the basis to compute higher moments of generalized order statistics from the corresponding lower-order moments.Generalized order statistics pro-vides several models of ordered data as a special case.The moments of general-ized order statistics also provide moments of order statistics and record values as a special case.In this research,the recurrence relations for single,product,inverse and ratio moments of generalized order statistics will be obtained for Lindley–Weibull distribution.These relations will be helpful for obtained moments of gen-eralized order statistics from Lindley–Weibull distribution recursively.Special cases of the recurrence relations will also be obtained.Some characterizations of the distribution will also be obtained by using moments of generalized order statistics.These relations for moments and characterizations can be used in differ-ent areas of computer sciences where data is arranged in increasing order. 展开更多
关键词 generalized order statistics Lindley–Weibull distribution recurrence relations MOMENTS
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THE GENERALIZED EINSTEIN RELATION ON A COMPACT ORIENTABLE RIMANNIAN MANIFOLD
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作者 方海涛 龚光鲁 《Acta Mathematica Scientia》 SCIE CSCD 1994年第4期409-416,共8页
A generalized Einstein relation is established for a drifted Brownian motion on a compact orientable Remannian manifole. The original form of such relation comes from an explicit formula of diffusion coeffcient by usi... A generalized Einstein relation is established for a drifted Brownian motion on a compact orientable Remannian manifole. The original form of such relation comes from an explicit formula of diffusion coeffcient by using the autocorrelation function of the velocity of the Einstein fluctuation theory of the diffusion process 展开更多
关键词 THE generalized EINSTEIN relation ON A COMPACT ORIENTABLE RIMANNIAN MANIFOLD
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Correlation between human seizure-related gene 6 variants and idiopathic generalized epilepsy in a Southern Chinese Han population
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作者 Jianming Jiang Xiao ling Chen +8 位作者 Wenting Liu Yan Zhao Yangtai Guan Yan Han FengWang Jiajun Lu Zhiliang Yu Zhenfang Du Xianning Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第2期96-100,共5页
This study sought to analyze the genotype and gene mutations of human seizure-related gene 6 in 98 patients with idiopathic generalized epilepsy (non-febrile seizures), who were selected from three generations of th... This study sought to analyze the genotype and gene mutations of human seizure-related gene 6 in 98 patients with idiopathic generalized epilepsy (non-febrile seizures), who were selected from three generations of the Chinese Han population living in Shanghai, Zhejiang Province, Wuxi of Jiangsu Province, and Jiangxi Province of Southern China. Twenty-six patients' parents were available as a first-degree relatives group and 100 biologically unrelated healthy controls were collected as the control group. Based on the age of onset and seizure type, the patients were divided into six subgroups. Polymerase chain reaction and DNA direct sequencing analysis showed that the most frequent mutations c. 1249dupC (p.Gly418Argfx31 ) and c.1636A 〉 G (p.Thr546Ala) were detected in some idiopathic generalized epilepsy patients and tl^eir asymptomatic first-degree relatives (30.6% vs. 19.2% and 11.2% vs. 26.9%). A novel mutation c.1807G 〉A (p.Val603Met) was found in a patient with late-onset idiopathic generalized epilepsy. There was no significant difference in the incidence of these three mutations among the different subgroups of idiopathic generalized epilepsy and controls. Thus, further analysis of a larger population is needed to confirm the assumption that human seizure-related gene 6 is a susceptibility gene for idiopathic generalized epilepsy with various sub-syndromes. 展开更多
关键词 human seizure-related gene 6 non-febrile seizure generalized epilepsy MUTATION polymorphism genetic neural regeneration
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Lie symmetry and the generalized Hojman conserved quantity of Nielsen equations for a variable mass holonomic system of relative motion 被引量:5
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作者 张美玲 孙现亭 +2 位作者 王肖肖 解银丽 贾利群 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第11期19-22,共4页
Lie symmetry and the generalized Hojman conserved quantity of Nielsen equations for a variable mass holonomic system of relative motion are studied. The determining equation of Lie symmetry of Nielsen equations for a ... Lie symmetry and the generalized Hojman conserved quantity of Nielsen equations for a variable mass holonomic system of relative motion are studied. The determining equation of Lie symmetry of Nielsen equations for a variable mass holonomic system of relative motion under the infinitesimal transformations of groups is given. The expression of generalized Hojman conserved quantity deduced directly from Lie symmetry for a variable mass holonomic system of relative motion is obtained. An example is given to illustrate the application of the results. 展开更多
关键词 variable mass relative motion Lie symmetry generalized Hojman conserved quantity
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Generating Set of the Complete Semigroups of Binary Relations 被引量:1
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作者 Yasha Diasamidze Neset Aydin Ali Erdoğan 《Applied Mathematics》 2016年第1期98-107,共10页
Difficulties encountered in studying generators of semigroup of binary relations defined by a complete X -semilattice of unions D arise because of the fact that they are not regular as a rule, which makes their invest... Difficulties encountered in studying generators of semigroup of binary relations defined by a complete X -semilattice of unions D arise because of the fact that they are not regular as a rule, which makes their investigation problematic. In this work, for special D, it has been seen that the semigroup , which are defined by semilattice D, can be generated by the set . 展开更多
关键词 SEMIGROUPS Binary relation generated Set generators
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A GENERAL CONSTITUTIVE RELATION FOR FATIGUE CRACK GROWTH ANALYSIS OF METAL STRUCTURES 被引量:27
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作者 W.C. Cui and X.P. HuangSchool of Naval Architecture & Ocean Engineering, Shanghai Jiaotong University, Shanghai 200030, China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2003年第5期342-354,共13页
Crack growth rate curves are the fundamental material property for metal structures under fatigue loading. Although there are many crack growth rate curves available in the literature, few of them showed the capabilit... Crack growth rate curves are the fundamental material property for metal structures under fatigue loading. Although there are many crack growth rate curves available in the literature, few of them showed the capability to explain various special phenomena observed in tests. A modified constitutive relation recently proposed by McEvily and his co-workers showed very promising capability. This modified constitutive relation is further generalized by (1) introducing an unstable fracture condition; (2) defining a virtual strength to replace the yield stress; and (3) defining an overload and underload parameter. The performances of this general constitutive relation for fatigue crack growth is extensively studied and it is found that this general constitutive relation is able to explain various phenomena observed with particular strong capability on load sequence effect. 展开更多
关键词 metal fatigue S-N curve crack growth rate general constitutive relation mean stress effect load sequence effect
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Characterization of event-related potentials in obsessive compulsive disorder patients: Comparison with depression and generalized anxiety disorder patients 被引量:5
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作者 Yingzhi Lu Wenbin Zong +4 位作者 Hanzhen Dong Faxin Wang Jinyu PU Xingshi Chen Yunxiang Tang 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第12期938-941,共4页
BACKGROUND: Study results of event-refated potential in obsessive compulsive disorder (OCD) remain controversial, potentially as a result of different instruments utilized and their differing technical characterist... BACKGROUND: Study results of event-refated potential in obsessive compulsive disorder (OCD) remain controversial, potentially as a result of different instruments utilized and their differing technical characteristics. OBJECTIVE: To investigate the differences in several common event-related potentials, Le. contingent negative variations, P300, and mismatch negativity (MMN), in OCD patients, depression patients, generalized anxiety disorder (GAD) patients, and healthy controls. DESIGN, TIME AND SETTING: A case-control study was performed in the Department of Electrophysiology, Shanghai Mental Health Center from May 2002 to December 2005. PARTICIPANTS: A total of 38 OCD patients, 20 depression patients, and 18 GAD patients, who were diagnosed according to the criteria of Chinese Classification of Mental Disorders (Version 3), formulated by the Chinese Psychiatry Association, were selected from the Outpatient Department of Shanghai Mental Health Center. Patients with two or more the above diseases were excluded. In addition, 28 healthy people, gender and age matched, were selected as controls. METHODS: Contingent negative variations, P300, and MMN were recorded by a Nicolet Spirit Instrument. All electrodes were attached at Cz according to the Intemationa11020 system, with the mastoid leads as reference and Fpz as ground. MAIN OUTCOME MEASURES: Amplitude and latency of contingent negative variations, P300, and MMN. RESULTS: The contingent negative variations, P300, and MMN were different (P 〈 0.01). OCD patients showed an increased MI amplitude compared with controls, depression, and GAD patients (P 〈 0.01). Target P300 amplitudes were significantly lower in OCD, depression, and GAD patients compared with controls (P 〈 0.01). Moreover, N2 latency and latency of MMN were prolonged in OCD and depression groups compared with controls (P 〈 0.05). CONCLUSION: Event-related potentials were different in depression, GAD, and OCD patients and healthy controls. In particular, OCD patients exhibited unique characteristics. 展开更多
关键词 obsessive compulsive disorder DEPRESSION generalized anxiety disorder contingent negative variation event-related potential-P300 mismatch negativity
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General Relation Connecting the Fundamental Fields
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作者 Mukul Chandra Das Rampada Misra 《Journal of Modern Physics》 2012年第9期1311-1313,共3页
There are four fundamental forces;gravitational force, electromagnetic force, strong force and weak force, in the well known physics. The unified field theory considers the constructive relations among these forces or... There are four fundamental forces;gravitational force, electromagnetic force, strong force and weak force, in the well known physics. The unified field theory considers the constructive relations among these forces or fields. In the present work the fundamental relations have been studied and trial has been made to derive more significant relations among the known fields. This gives out a generalized unification. 展开更多
关键词 FUNDAMENTAL Force UNIFIED Field generalized relation
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The Power of Group Generators and Relations: An Examination of the Concept and Its Applications
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作者 Tiancheng Zhou 《Journal of Applied Mathematics and Physics》 2018年第11期2425-2444,共20页
This paper investigates the approach of presenting groups by generators and relations from an original angle. It starts by interpreting this familiar concept with the novel notion of “formal words” created by juxtap... This paper investigates the approach of presenting groups by generators and relations from an original angle. It starts by interpreting this familiar concept with the novel notion of “formal words” created by juxtaposing letters in a set. Taking that as basis, several fundamental results related to free groups, such as Dyck’s Theorem, are proven. Then, the paper highlights three creative applications of the concept in classifying finite groups of a fixed order, representing all dihedral groups geometrically, and analyzing knots topologically. All three applications are of considerable significance in their respective topic areas and serve to illustrate the advantages and certain limitations of the approach flexibly and comprehensively. 展开更多
关键词 generators and relationS Free GROUP Dyck’s Theorem Dihedral GROUP Presentation Classification of Finite GROUPS (Application) Realizing Dihedral GROUPS Geometrically (Application) KNOT GROUP (Application)
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General calculation formulas and recurrence relations of radial matrix elements for relativistic n-dimensional hydrogen atom of spin S=0 被引量:1
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作者 CHENChang-yuan LUFa-lin SUNDong-sheng 《原子与分子物理学报》 CAS CSCD 北大核心 2004年第3期432-440,共9页
In this paper, the general calculation formulas of radial matrix elements for relativistic n-dimensional hydrogen atom of spin S=0 are obtained, and the recurrence relation of different power order radial matrix eleme... In this paper, the general calculation formulas of radial matrix elements for relativistic n-dimensional hydrogen atom of spin S=0 are obtained, and the recurrence relation of different power order radial matrix elements are also derived. 展开更多
关键词 n-dimensional hydrogen atom-type potential Klein-Cordon equation Radial matrix dements generAL calculation FORMULAS RECURRENCE relations
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Health Related Quality of Life and Mental Health in ICU Survivors: Post-Intensive Care Syndrome Follow-Up and Correlations between the 36-Item Short Form Health Survey (SF-36) and the General Health Questionnaire (GHQ-28) 被引量:1
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作者 Stefano Tugnoli Savino Spadaro +3 位作者 Francesca Dalla Corte Giorgia Valpiani Carlo Alberto Volta Stefano Caracciolo 《Health》 CAS 2022年第5期477-506,共30页
We investigated the relationship between health-related quality of life (HRQOL) and psychological distress in intensive care unit (ICU) survivors 12 months after ICU discharge. The purpose of this study, conducted and... We investigated the relationship between health-related quality of life (HRQOL) and psychological distress in intensive care unit (ICU) survivors 12 months after ICU discharge. The purpose of this study, conducted and completed before the onset of the COVID-19 pandemic, was to find correlations among psychiatric symptoms detected by a screening tool as the General Health Questionnaire-28 (GHQ-28) and the different domains of HRQOL measured with the SF-36 health survey (SF-36), in order to identify ICU survivors with Post-Intensive Care Syndrome (PICS) who need a specific psychiatric intervention to improve their HRQOL. Among 298 ICU survivors who stayed in the ICU for at least 72 hours, 48 patients were enrolled one year after discharge undergoing a clinical interview to assess their functional impairment (Barthel index), mental health (GHQ-28), and health-related quality of life (SF-36). 19% of those subjects had a GHQ-28 ≥ 5 and were identified as “psychiatric cases”, and they were older and experienced a greater impairment in HRQOL. Anxiety, insomnia, and depressive symptoms seemed to be particularly involved in the impairment of HRQOL. A negative correlation between GHQ-28 total scores and subscales and SF-36 subscales was found. Our findings highlighted that psychological distress in ICU survivors may negatively impact physical health recovery and quality of life;conversely, physical impairment and functional disability may trigger the onset of psychiatric symptoms after discharge. The present study is firstly to investigate the correlations between HRQOL and psychological distress in ICU survivors through the GHQ-28, and then affirms the need to carry out follow-up checks for psychiatric symptoms in ICU survivors. 展开更多
关键词 ICU Survivors Psychological Distress Health-related Quality of Life SF-36 Health Survey Scaled general Health Questionnaire (GHQ-28)
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Research on the Relationship between Job Satisfaction and Harmony in Human Relations among New Female Generation
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作者 GAO Qingyi 《International English Education Research》 2017年第2期29-32,共4页
关键词 工作满意度 和谐关系 人际关系 女性 员工满意度 知识经济 人才市场 新生代
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Generalized δ-entropy condition to Riemann solution for Chaplygin gas in traffic flow 被引量:1
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作者 Wancheng SHENG Ying ZENG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第3期353-364,共12页
The Riemann problem for the Aw-Rascle model in the traffic flow with the Delta initial data for the Chaplygin gas is studied. The solutions are constructed globally under the generalized Rankine-Hugoniot relations, t... The Riemann problem for the Aw-Rascle model in the traffic flow with the Delta initial data for the Chaplygin gas is studied. The solutions are constructed globally under the generalized Rankine-Hugoniot relations, the δ-entropy conditions, and the generalized δ-entropy conditions. A new Delta wave, which is called a primary Delta wave, is defined in some solutions. The primary Delta wave satisfies the generalized Rankine- Hugoniot relations and the generalized δ-entropy conditions. It generates initially from the Delta initial data, which either evaluates a Delta wave, whose weight becomes stronger and stronger, or disappears at a finite time. 展开更多
关键词 generalized δ-entropy condition Riemann problem for Aw-Rascle model generalized rankine-hugoniot relation Delta initial datum Chaplygin gas
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Adversarial Learning for Distant Supervised Relation Extraction 被引量:6
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作者 Daojian Zeng Yuan Dai +2 位作者 Feng Li R.Simon Sherratt Jin Wang 《Computers, Materials & Continua》 SCIE EI 2018年第4期121-136,共16页
Recently,many researchers have concentrated on using neural networks to learn features for Distant Supervised Relation Extraction(DSRE).These approaches generally use a softmax classifier with cross-entropy loss,which... Recently,many researchers have concentrated on using neural networks to learn features for Distant Supervised Relation Extraction(DSRE).These approaches generally use a softmax classifier with cross-entropy loss,which inevitably brings the noise of artificial class NA into classification process.To address the shortcoming,the classifier with ranking loss is employed to DSRE.Uniformly randomly selecting a relation or heuristically selecting the highest score among all incorrect relations are two common methods for generating a negative class in the ranking loss function.However,the majority of the generated negative class can be easily discriminated from positive class and will contribute little towards the training.Inspired by Generative Adversarial Networks(GANs),we use a neural network as the negative class generator to assist the training of our desired model,which acts as the discriminator in GANs.Through the alternating optimization of generator and discriminator,the generator is learning to produce more and more discriminable negative classes and the discriminator has to become better as well.This framework is independent of the concrete form of generator and discriminator.In this paper,we use a two layers fully-connected neural network as the generator and the Piecewise Convolutional Neural Networks(PCNNs)as the discriminator.Experiment results show that our proposed GAN-based method is effective and performs better than state-of-the-art methods. 展开更多
关键词 relation extraction generative adversarial networks distant supervision piecewise convolutional neural networks pair-wise ranking loss
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Spatial Relation Resolution and Spatial Relation Abstraction 被引量:2
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作者 AlTinghua LIUYaolin 《Geo-Spatial Information Science》 2003年第4期10-16,共7页
This paper attempts toregard spatial relation transformationas an important process in map gener-alization. The spatial relation generali-zation can be divided into the compo-nents of abstraction: topology, dis-tance ... This paper attempts toregard spatial relation transformationas an important process in map gener-alization. The spatial relation generali-zation can be divided into the compo-nents of abstraction: topology, dis-tance and orientation. The concept‘ spatial relation resolution' is intro-duced to describe the constraints ofrelative spatial relation. On the basisof nine intersection models, the cardi-nal direction models and the iso-dis-tance-relation models, this paper givesthree sorts of relation resolution repre-sentations for topological, distance andorientation relation, respectively. Twomapping implementations in map gen-eralization is discussed. 展开更多
关键词 空间关系 转换 拓扑学 绘制地图
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A systematic review: How to choose appropriate health-related quality of life (HRQOL) measures in routine general practice? 被引量:2
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作者 陈天辉 李鲁 KOCHEN Michael M 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2005年第9期936-940,共5页
In more recent times, health-related quality of life (HRQOL) measurements have formed an important part of as- sessing the quality of routine care in general practice. For a measure to have clinical usefulness it must... In more recent times, health-related quality of life (HRQOL) measurements have formed an important part of as- sessing the quality of routine care in general practice. For a measure to have clinical usefulness it must not only be valid, appro- priate, reliable, responsive, and capable of being interpreted, but it must also be simple, fast to complete, easy to score, and provide useful clinical data. The Two-step method of choosing appropriate measures is introduced. Then through comparison of generic instruments with disease-specific instruments, we can conclude that sometimes a combination of generic and disease-specific HRQOL measures may be more appropriate for monitoring changes in a patient’s health status due to an intervention. 展开更多
关键词 身体健康 生活质量 疾病预防 保健方法
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Uncertainty relations in the product form
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作者 黄晓芬 张廷桂 景乃桓 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第7期203-206,共4页
We study the uncertainty relation in the product form of variances and obtain some new uncertainty relations with weight, which are shown to be tighter than those derived from the Cauchy-Schwarz inequality.
关键词 uncertainty relation OBSERVABLES generalized Cauchy-Schwarz inequality
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EXISTENCE OF SOLUTIONS FOR GENERALIZEDQUASI-VARIATIONAL-LIKE INEQUALITIES
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作者 丁协平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1997年第2期141-150,共10页
In this paper, some existence theorems of solutions for a class of generalized quasi-variational-like inequalities with discontinuous mappings ape proved under paracompact setting in topological vector spaces. These t... In this paper, some existence theorems of solutions for a class of generalized quasi-variational-like inequalities with discontinuous mappings ape proved under paracompact setting in topological vector spaces. These theorems unify, improve and generalize many recent results. 展开更多
关键词 topological vector space generalized quasi-variational-like inequality 0-diagonally concave 0-diagonally concave relation
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