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General awareness of symptoms of myocardial infarction and the need for urgent treatment:A cross-sectional,street survey in Chennai,Tamil Nadu
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作者 Thirumurugan E Gomathi K +4 位作者 Swathy P Syed Ali Afrin Ponduri Lakshmi Alekhya Jishnu B Banashree Das 《Journal of Acute Disease》 2023年第2期51-56,I0001-I0003,共9页
Objective:To investigate the golden-time-awareness of and the necessary actions in response to acute myocardial infarction among the general public.Methods:This study was conducted with the use of a descriptive resear... Objective:To investigate the golden-time-awareness of and the necessary actions in response to acute myocardial infarction among the general public.Methods:This study was conducted with the use of a descriptive research design and convenience sampling.A sample of 800 subjects,using self-structured knowledge questionnaires,was selected for data collection and analysis.The study was conducted at Dr.M.G.R.Educational and Research Institute,India,from February to November 2022.Awareness of myocardial infarction symptoms and intervention timeline(the golden time)was investigated.A multivariate logistic regression analysis was performed to identify the demographic factors affecting the recognition of the golden time of acute myocardial infarction.Results:A total of 800 subjects were included.Among the subjects,367(45.8%)were male,433(54.2%)were female,and 443(55.3%)participants failed to recognize the golden time.Our multivariate logistic regression analysis showed that people with a bachelor’s degree(OR=0.41,95%CI:0.23-0.74,P=0.03)and a high school level diploma(OR=0.55,95%CI:0.31-0.97,P=0.03)are more likely to know about myocardial infarction(golden time)than illiterate people.Additionally,people who are employed(OR=0.59,95%CI:0.41-0.85,P=0.05)are more likely to know about myocardial infarction(golden time)than those who are not.Conclusions:The majority of people in the awareness group realize that taking myocardial infarction patients to the hospital would be the best course of action.The unawareness of the ideal treatment window for myocardial infarction may cause a delay in seeking medical attention,which can lead to an increase in mortality and morbidity. 展开更多
关键词 Heart attack Intervention timeline SYMPTOMS TREATMENT Myocardial infarction Percutaneous coronary interven­tion
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Correlation of Abortus Imminence Cases in the First Trimester with Biochemical Markers
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作者 Küçükyurt Ayça Kubat Basat Dilara +2 位作者 Bingöl Bugra Berkan Artuğ Cansızlar Gülnihal İlhan Gülşah 《Open Journal of Obstetrics and Gynecology》 CAS 2023年第2期207-213,共7页
Objective: In this study, we compared the biochemical markers of imminent abortion, missed abortion, and healthy pregnant women in the first trimester to see if there were any differences. Materials and Methods: The s... Objective: In this study, we compared the biochemical markers of imminent abortion, missed abortion, and healthy pregnant women in the first trimester to see if there were any differences. Materials and Methods: The study method is prospective. Pregnant women who applied to the obstetrics clinic of Istanbul Training and Research Hospital between 01.04.22 and 31.10.22 were diagnosed with abortion imminens or missed abortion between 6 weeks and 12 weeks or had normal pregnancy follow-up, had no chronic diseases, and did not take magnesium and calcium supplements were included in the study. 20 pregnant women with missed abortion, 20 pregnant women with abortion imminens diagnosis and 20 normal pregnant women who met the criteria were included in the study. Magnesium (Mg), calcium (Ca), copper (Cu), zinc (Zn) and hemogram (CBC) levels were checked in pregnant women included in the study. Results: The Mg, Cu, Zn, and CBC values of the study participants’ women did not differ in a statistically significant way. When compared to pregnant women who had a normal pregnancy process, the difference in Ca value was found to be statistically substantially smaller in pregnant women who were diagnosed with abortion imminens and missed abortion. The findings of our study suggest that serum Ca levels be measured prior to conception or at the initial visit. Conclusion: Serum Ca levels were found to be significantly lower in the missed abortion group than in the abortus imminens and normal pregnant groups in our study (p 0.05). 展开更多
关键词 ABORtion Biochemical Markers CALCIUM Copper MAGNESIUM Missed Abor-tion Spontaneous Abortion Zinc
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Electroacupuncture improves microcirculation and neuronal morphology in the spinal cord of a rat model of intervertebral disc extrusion 被引量:9
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作者 Dai-xun Jiang Zhi-song Lu +4 位作者 Ge-bin Li Sheng-yong Sun Xiang Mu Peter Lee Wu Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第2期237-243,共7页
Most studies on spinal cord neuronal injury have focused on spinal cord tissue histology and the expression of nerve cell damage and repair-related genes. The importance of the microcirculation is often ignored in spi... Most studies on spinal cord neuronal injury have focused on spinal cord tissue histology and the expression of nerve cell damage and repair-related genes. The importance of the microcirculation is often ignored in spinal cord injury and repair research. Therefore, in this study, we established a rat model of intervertebral disc extrusion by inserting a silica gel pad into the left ventral sur-face of T13. Electroacupuncture was used to stimulate the bilateralZusanlipoint (ST36) and Neiting point (ST44) for 14 days. Compared with control animals, blood lfow in the ifrst lumbar vertebra (L1) was noticeably increased in rats given electroacupuncture. Microvessel density in the T13 segment of the spinal cord was increased significantly as well. The number of normal neurons was higher in the ventral horn of the spinal cord. In addition, vacuolation in the white matter was lessened. No obvious glial cell proliferation was visible. Furthermore, hindlimb motor function was improved signiifcantly. Collectively, our results suggest that electroacupuncture can improve neuronal morphology and microcirculation, and promote the recovery of neurological functions in a rat model of intervertebral disc extrusion. 展开更多
关键词 nerve regeneration ELECTROACUPUNCTURE intervertebral disc blood circulation inflamma-tion neuroprotection motor function neurons NSFC grants neural regeneration
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Picture Fuzzy Relations over Picture Fuzzy Sets
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作者 Mohammad Kamrul Hasan Abeda Sultana Nirmal Kanti Mitra 《American Journal of Computational Mathematics》 2023年第1期161-184,共24页
Nowadays, picture fuzzy set theory is a flourishing field in mathematics with uncertainty by incorporating the concept of positive, negative and neutral membership degrees of an object. A traditional crisp relation re... Nowadays, picture fuzzy set theory is a flourishing field in mathematics with uncertainty by incorporating the concept of positive, negative and neutral membership degrees of an object. A traditional crisp relation represents the satisfaction or the dissatisfaction of relationship, connection or correspondence between the objects of two or more sets. However, there are some problems that can’t be solved through classical relationships, such as the relationship between two objects being vague. In those situations, picture fuzzy relation over picture fuzzy sets is an important and powerful concept which is suitable for describing correspondences between two vague objects. It represents the strength of association of the elements of picture fuzzy sets. It plays an important role in picture fuzzy modeling, inference and control system and also has important applications in relational databases, approximate reasoning, preference modeling, medical diagnosis, etc. In this article, we define picture fuzzy relations over picture fuzzy sets, including some other fundamental definitions with illustrations. The max-min and min-max compositions of picture fuzzy relations are defined in the light of picture fuzzy sets and discussed some properties related to them. The reflexivity, symmetry and transitivity of a picture fuzzy relation are described over a picture fuzzy set. Finally, various properties are explored related to the picture fuzzy relations over a picture fuzzy set. 展开更多
关键词 Picture Fuzzy Sets Picture Fuzzy Relations Picture Fuzzy Binary Rela-tions Composition of Picture Fuzzy Relations
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Repetitive transcranial magnetic stimulation for hallucination in schizophrenia spectrum disorders A meta-analysis 被引量:8
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作者 Yingli Zhang Wei Liang +3 位作者 Shichang Yang Ping Dai Lijuan Shen Changhong Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第28期2666-2676,共11页
OBJECTIVE: This study assessed the efficacy and tolerability of repetitive transcranial magnetic stimulation for treatment of auditory hallucination of patients with schizophrenia spectrum disorders. DATA SOURCES: O... OBJECTIVE: This study assessed the efficacy and tolerability of repetitive transcranial magnetic stimulation for treatment of auditory hallucination of patients with schizophrenia spectrum disorders. DATA SOURCES: Online literature retrieval was conducted using PubMed, ISI Web of Science, EMBASE, Medline and Cochrane Central Register of Controlled Trials databases from January 1985 to May 2012. Key words were "transcranial magnetic stimulation", "TMS", "repetitive tran- scranial magnetic stimulation", and "hallucination". STUDY SELECTION: Selected studies were randomized controlled trials assessing therapeutic ef- ficacy of repetitive transcranial magnetic stimulation for hallucination in patients with schizophrenia spectrum disorders. Experimental intervention was low-frequency repetitive transcranial magnetic stimulation in left temporoparietal cortex for treatment of auditory hallucination in schizophrenia spectrum disorders. Control groups received sham stimulation. MAIN OUTCOME MEASURES: The primary outcome was total scores of Auditory Hallucinations Rating Scale, Auditory Hallucination Subscale of Psychotic Symptom Rating Scale, Positive and Negative Symptom Scale-Auditory Hallucination item, and Hallucination Change Scale. Secondary outcomes included response rate, global mental state, adverse effects and cognitive function. RESULTS: Seventeen studies addressing repetitive transcranial magnetic stimulation for treatment of schizophrenia spectrum disorders were screened, with controls receiving sham stimulation. All data were completely effective, involving 398 patients. Overall mean weighted effect size for repeti- tive transcranial magnetic stimulation versus sham stimulation was statistically significant (MD = -0.42, 95%C/: -0.64 to -0.20, P = 0.000 2). Patients receiving repetitive transcranial magnetic stimulation responded more frequently than sham stimulation (OR = 2.94, 95%C/: 1.39 to 6.24, P =0.005). No significant differences were found between active repetitive transcranial magnetic stimulation and sham stimulation for positive or negative symptoms. Compared with sham stimulation, active repeti- tive transcranial magnetic stimulation had equivocal outcome in cognitive function and commonly caused headache and facial muscle twitching. CONCLUSION: Repetitive transcranial magnetic stimulation is a safe and effective treatment for auditory hallucination in schizophrenia spectrum disorders, 展开更多
关键词 neural regeneration META-ANALYSIS transcranial magnetic stimulation auditory hallucination schizophre-nia schizophrenia spectrum disorders schizophreniform disorder temporoparietal cortex cognitive func-tion positive symptom grants-supported paper NEUROREGENERAtion
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Existence results for unilateral contact problem with friction of thermo-electro-elasticity 被引量:1
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作者 H.BENAISSA EL-H.ESSOUFI R.FAKHAR 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第7期911-926,共16页
This work studies a mathematical model describing the static process of contact between a piezoelectric body and a thermally-electrically conductive foundation. The behavior of the material is modeled with a thermo-el... This work studies a mathematical model describing the static process of contact between a piezoelectric body and a thermally-electrically conductive foundation. The behavior of the material is modeled with a thermo-electro-elastic constitutive law. The contact is described by Signorini's conditions and Tresca's friction law including the electrical and thermal conductivity conditions. A variational formulation of the model in the form of a coupled system for displacements, electric potential, and temperature is de- rived. Existence and uniqueness of the solution are proved using the results of variational inequalities and a fixed point theorem. 展开更多
关键词 static frictional contozt thermo-piezoelectric material Signorini's condi-tion Tresca's friction frictional heat generation variational inequality fixed point process
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Energy Consumption Analysis and Optimization of Electric Submersible Pump System
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作者 Lingyu Li 《Engineering(科研)》 CAS 2023年第5期269-274,共6页
Electric submersible pumps account for a considerable proportion in the development of the Bohai Oilfield. Improving the system efficiency of the electric submersible pump wells, ensuring that the units operate in the... Electric submersible pumps account for a considerable proportion in the development of the Bohai Oilfield. Improving the system efficiency of the electric submersible pump wells, ensuring that the units operate in the high-efficiency zone, is essential. Analysis shows that the efficiency of the electric submersible pump system depends on the wear and tear of each component of the submersible pump equipment, the setting of operational parameters, and more importantly, the production status and daily management level of the oil well. Therefore, improving the structural performance of the submersible pump product, optimizing the parameters setting of the oil well, strengthening daily management, establishing a scientific management system, and improving the production management process and system can effectively improve the production efficiency and economic benefits of the oil well, and further achieve the goal of energy saving and emission reduction. In addition, it is necessary to actively promote the concept and technology of energy saving and emission reduction, encourage oilfield enterprises to explore effective measures to reduce the energy consumption of the electric submersible pump system by strengthening the scientific management system, and achieve a green, low-carbon, and high-quality development of oilfield production to achieve the unity of economic benefits, social benefits, and environmental benefits. This article applies the above measures in the P oilfield to achieve energy optimization of submersible electric pump systems, reducing the daily power consumption of single well submersible electric pump systems by 371 kWh per day, increasing the submersible electric pump's lifespan by 200 days, generating considerable project benefits. 展开更多
关键词 Offshore Oil Fields Electric Submersible Pumps System Energy Consump-tion System Efficiency Energy Conservation and Consumption Reduction
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Modeling Cyber Loss Severity Using a Spliced Regression Distribution with Mixture Components
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作者 Meng Sun 《Open Journal of Statistics》 2023年第4期425-452,共28页
Cyber losses in terms of number of records breached under cyber incidents commonly feature a significant portion of zeros, specific characteristics of mid-range losses and large losses, which make it hard to model the... Cyber losses in terms of number of records breached under cyber incidents commonly feature a significant portion of zeros, specific characteristics of mid-range losses and large losses, which make it hard to model the whole range of the losses using a standard loss distribution. We tackle this modeling problem by proposing a three-component spliced regression model that can simultaneously model zeros, moderate and large losses and consider heterogeneous effects in mixture components. To apply our proposed model to Privacy Right Clearinghouse (PRC) data breach chronology, we segment geographical groups using unsupervised cluster analysis, and utilize a covariate-dependent probability to model zero losses, finite mixture distributions for moderate body and an extreme value distribution for large losses capturing the heavy-tailed nature of the loss data. Parameters and coefficients are estimated using the Expectation-Maximization (EM) algorithm. Combining with our frequency model (generalized linear mixed model) for data breaches, aggregate loss distributions are investigated and applications on cyber insurance pricing and risk management are discussed. 展开更多
关键词 Cyber Risk Data Breach Spliced Regression Model Finite Mixture Distribu-tion Cluster Analysis Expectation-Maximization Algorithm Extreme Value Theory
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APPLICATIONS OF HYPERGEOMETRIC SUMMATION THEOREMS OF KUMMER AND DIXON INVOLVING DOUBLE SERIES 被引量:1
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作者 H.M.SRIVASTAVA M.I.QURESHI +1 位作者 Kaleem A.QURAISHI Ashish ARORA 《Acta Mathematica Scientia》 SCIE CSCD 2014年第3期619-628,共10页
Using series iteration techniques identities and apply each of these identities in we derive a number of general double series order to deduce several hypergeometric reduction formulas involving the Srivastava-Daoust ... Using series iteration techniques identities and apply each of these identities in we derive a number of general double series order to deduce several hypergeometric reduction formulas involving the Srivastava-Daoust double hypergeometric function. The results presented in this article are based essentially upon the hypergeometric summation theorems of Kummer and Dixon. 展开更多
关键词 Pochhammer's symbol Gamma function series identities hypergeometric re-duction formulas Srivastava-Daoust double and multiple hypergeometric func-tions Legendre's duplication formula Gauss-Legendre multiplication formula Kummer's theorem Dixon's theorem
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动词+-ion(-tion,-ation)=名词
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作者 喻安民 《语言教育》 1992年第1期40-41,共2页
英语中有大量的名词是以-tion结尾的,而这些名词绝大多数是由动词后加-ion、-tion、-ation、-ition-ution等派生而成的。其构词方法如下: 一、一般以t结尾的动词后面直接加-ion构成-tion名词:act-action 行为,作用 adopt-adoption 采用c... 英语中有大量的名词是以-tion结尾的,而这些名词绝大多数是由动词后加-ion、-tion、-ation、-ition-ution等派生而成的。其构词方法如下: 一、一般以t结尾的动词后面直接加-ion构成-tion名词:act-action 行为,作用 adopt-adoption 采用collect-collection 收集,收藏物 elect-election 选举二、一般以-te结尾的动词去e加-ion: 展开更多
关键词 tion 构词方法 ELECtion adopt COLLECtion SORPtion 吸附作用 RESOLVE simplify REVOLUtion
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Quantitative volumetric analysis of the optic radiation in the normal human brain using diffusion tensor magnetic resonance imaging-based tractography
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作者 Dong-Hoon Lee Ji-Won Park Cheol-Pyo Hong 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第3期280-284,共5页
To attain the volumetric information of the optic radiation in normal human brains, we per- formed diffusion tensor imaging examination in 13 healthy volunteers. Simultaneously, we used a brain normalization method to... To attain the volumetric information of the optic radiation in normal human brains, we per- formed diffusion tensor imaging examination in 13 healthy volunteers. Simultaneously, we used a brain normalization method to reduce individual brain variation and increase the accuracy of volumetric information analysis. In addition, tractography-based group mapping method was also used to investigate the probability and distribution of the optic radiation pathways. Our results showed that the measured optic radiation fiber tract volume was a range of about 0.16% and that the fractional anisotropy value was about 0.53. Moreover, the optic radiation probability fiber pathway that was determined with diffusion tensor tractography-based group mapping was able to detect the location relatively accurately. We believe that our methods and results are help- ful in the study of optic radiation fiber tract information. 展开更多
关键词 nerve regeneration optic radiation diffusion tensor imaging diffusion tensor tractogra-phy magnetic resonance imaging volumetric analysis probability map group mapping visualiza-tion individual variation neural regeneration
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Early rehabilitation improves neurofunctional outcome after surgery in children with spinal tumors 被引量:4
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作者 Nezire Kose Ozge Muezzinoglu +3 位作者 Sevil Bilgin Sevilay Karahan Ilkay Is kay Burcak Bilginer 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第2期129-134,共6页
To investigate the effect of early rehabilitation on neurofunctional outcome after surgery in chil- dren with spinal tumors, this study reviewed the medical charts and radiographic records of 70 pediatric patients (1... To investigate the effect of early rehabilitation on neurofunctional outcome after surgery in chil- dren with spinal tumors, this study reviewed the medical charts and radiographic records of 70 pediatric patients (1-17 years old) who received spinal tumor surgical removal. The peddiatric patients received rahabilitation treatment at 4 (range, 2-7) days after surgery for 10 (range, 7-23) days. Results from the Modified McCormick Scale, Functional Independence Measure for Chil- dren, American Spinal Injury Association Impairment Scale and Karnofsky Performance Status Scale demonstrated that the sensory function, motor function and activity of daily living of pedi- atric children who received early rehabilitation were significantly improved. Results also showed that tumor setting and level localization as well as patients's clinical symptoms have no influences on neurofunctional outcomes. 展开更多
关键词 nerve regeneration spinal cord injury spinal cord tumor CHILDREN rehabilitation func-tion SENSE motor retrospective analysis neural regeneration
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THREE SOLUTIONS FOR A FRACTIONAL ELLIPTIC PROBLEMS WITH CRITICAL AND SUPERCRITICAL GROWTH 被引量:1
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作者 张金国 刘晓春 《Acta Mathematica Scientia》 SCIE CSCD 2016年第6期1819-1831,共13页
In this paper, we deal with the existence and multiplicity of solutions to the frac- tional elliptic problems involving critical and supercritical Sobolev exponent via variational arguments. By means of the truncation... In this paper, we deal with the existence and multiplicity of solutions to the frac- tional elliptic problems involving critical and supercritical Sobolev exponent via variational arguments. By means of the truncation combining with the Moser iteration, we prove that our problem has at least three solutions. 展开更多
关键词 fractional elliptic equation variational methods three solutions Moser itera-tion
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Meteorological applications of precipitable water vapor measurements retrieved by the national GNSS network of China 被引量:7
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作者 Liang Hong Cao Yunchang +3 位作者 Wan Xiaomin Xu Zhifang Wang Haishen Hu Heng 《Geodesy and Geodynamics》 2015年第2期135-142,共8页
In this study, the Global Navigation Satellite System (GNSS) network of China is discussed, which can be used to monitor atmospheric precipitable water vapor (PWV). By the end of 2013, the network had 952 GNSS sit... In this study, the Global Navigation Satellite System (GNSS) network of China is discussed, which can be used to monitor atmospheric precipitable water vapor (PWV). By the end of 2013, the network had 952 GNSS sites, including 260 belonging to the Crustal Movement Observation Network of China (CMONOC) and 692 belonging to the China Meteorological Administration GNSS network (CMAGN). Additionally, GNSS observation collecting and data processing procedures are presented and PWV data quality control methods are investigated. PWV levels as determined by GNSS and radiosonde are compared. The results show that GNSS estimates are generally in good agreement with measurements of radio- sondes and water vapor radiometers (WVR). The PWV retrieved by the national GNSS network is used in weather forecasting, assimilation of data into numerical weather prediction models, the validation of PWV estimates by radiosonde, and plum rain monitoring. The network is also used to monitor the total ionospheric electron content. 展开更多
关键词 Precipitable water vapor (PWV) Global navigation satellite system(GNSS) Crustal Movement ObservationNetwork of China (CMONOC)China meteorological administra-tion GNSS network (CMAGN) Water vapor radiometers (WVR) Quality control Meteorological application Assimilation
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A simulation study of water property changes using geometrical alteration in SPC/E
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作者 李明儒 张楠 张丰收 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第8期204-211,共8页
We present a systematic investigation of the impact of changing the geometry structure of the SPC/E water model by performing a series of molecular dynamic simulations at 1 bar (1 bar = 105 Pa) and 298.15 K. The geo... We present a systematic investigation of the impact of changing the geometry structure of the SPC/E water model by performing a series of molecular dynamic simulations at 1 bar (1 bar = 105 Pa) and 298.15 K. The geometric modification includes altering the H-O-H angle range from 90° to 115° and modifying the O-H length range from 0.90 A to 1.10 A in the SPC/E model. The former is achieved by keeping the dipole moment constant by modifying the O-H length, while in the latter only the O-H length is changed. With the larger bond length and angle, we find that the liquid shows a strong quadrupole interaction and high tetrahedral structure order parameter, resulting in the enhancement of the network structure of the liquid. When the bond length or angle is reduced, the hydrogen bond lifetime and self-diffusion constant decrease due to the weakening of the intermolecular interaction. We find that modifying the water molecular bond length leading to the variation of the intermolecular interaction strength is more intensive than changing the bond angle. Through calculating the average reduced density gradient and thermal fluctuation index, it is found that the scope of vdW interaction with neighbouring water molecules is inversely proportional to the change of the bond length and angle. The effect is mainly due to a significant change of the hydrogen bond network. To study the effect of water models as a solvent whose geometry has been modified, the solutions of ions in different solvent environments are examined by introducing NaCI. During the dissolving process, NaCI ions are ideally dissolved in SPC/E water and bond with natural water more easily than with other solvent models. 展开更多
关键词 molecular dynamics simulation geometric modification intermolecular interaction ion's solva-tion
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AN OVERVIEW ON THE URBAN-RURAL INTERACTION IN THE PAST 50 YEARS IN CHINA 被引量:4
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作者 Qi Lu Jin-yan Zhan Kang-won Lee 《Chinese Geographical Science》 SCIE CSCD 2001年第3期2-9,共8页
China is a country with a long history of agricultural development,the tr adition of bureaucratic administra-tion and economic management system s for the social development.In its t ransition from traditional society... China is a country with a long history of agricultural development,the tr adition of bureaucratic administra-tion and economic management system s for the social development.In its t ransition from traditional society to modern soci-ety during the past 50years,the rela tions between rural areas and urban a reas have been kept abnormal if considered from the point of view of the modernized co untries.Today,China still has its more than 70percent of population,bu t limited capital,lower technology and underdeveloped culture,in the rural areas.This unbalance forms not only the o bstacles to China’s modernization of social development,but also the barriers to th e society,economy and environment sustainable devel-opment.This paper focuses on the dis cussion about the coordinate develo pment of the relations between rural and urban in the past 50years,and the authors hold that only has the abnormal relation between the two areas been corrected,could China’s future development of natio nal economy be successful. 展开更多
关键词 urban-rural interaction coordin ATE DEVELOPMENT of urban-rural RELA tion DEVELOPMENT of national econo-my
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CAVITY FORMATION AND ITS VIBRATION FOR A CLASS OF GENERALIZED INCOMPRESSIBLE HYPER-ELASTIC MATERIALS 被引量:6
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作者 YuanXuegang ZhuZhengyou ChengChangjun 《Acta Mechanica Solida Sinica》 SCIE EI 2004年第4期361-369,共9页
The problem of radial symmetric motion for a solid sphere composed of a class of generalized incompressible neo-Hookean materials, subjected to a suddenly applied surface tensile dead load, is examined.The ana... The problem of radial symmetric motion for a solid sphere composed of a class of generalized incompressible neo-Hookean materials, subjected to a suddenly applied surface tensile dead load, is examined.The analytic solutions for this problem and the motion equation of cavity that describes cavity formation and growth with time are obtained. The e?ect of radial perturbation of the materials on cavity formation and its motion is discussed. The plane of the perturbation parameters of the materials is divided into four regions. The existential conditions and qualitative properties of solutions of the motion equation of the cavity are studied in di?erent parameters’ regions in detail. It is proved that the cavity motion with time is a nonlinear periodic vibration. The vibration center is then determined. 展开更多
关键词 generalized incompressible neo-Hookean materials analytic solution motion equa- tion of cavity nonlinear periodic vibration
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Driving force coordinated control of an 8x8 in-wheel motor drive vehicle with tire-road friction coefficient identification 被引量:4
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作者 Zheng Zhang Chun-guang Liu +2 位作者 Xiao-jun Ma Yun-yin Zhang Lu-ming Chen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第1期119-132,共14页
Because of the complexities of tire-road interaction,the wheels of a multi-wheel distributed electricdrive vehicle can easily slip under certain working conditions.As wheel slip affects the dynamic per-formance and st... Because of the complexities of tire-road interaction,the wheels of a multi-wheel distributed electricdrive vehicle can easily slip under certain working conditions.As wheel slip affects the dynamic per-formance and stability of the vehicle,it is crucial to control it and coordinate the driving force.With this aim,this paper presents a driving force coordination control strategy with road identification for eight-wheeled electric vehicles equipped with an in-wheel motor for each wheel.In the proposed control strategy,the road identification module estimates tire-road forces using an unscented Kalman filter al-gorithm and recognizes the road adhesion coefficient by employing the recursive least-square method According to road identification,the optimal sip ratio under the current driving condition is obtainedand a controller based on sliding mode control with a conditional integrator uses this value for accel-eration slip regulation.The anti-slip controller obtains the adjusting torque,which is integrated with the driver-command-based feedforward control torque to implement driving force coordination control.The results of hardware-in-loop simulation show that this control strategy can accurately estimate tire-roadrces as well as the friction coefficient,and thus,can effectively fulfill the purpose of driving force coordinated control under different driving conditions. 展开更多
关键词 In-wheel motor Tire-road friction coefficient Slip ratio Sliding mode control Conditional integrator Accelera tion slip regulation
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A Mobile Localization Strategy for Wireless Sensor Network in NLOS Conditions 被引量:7
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作者 Long Cheng Yan Wang +2 位作者 Xingming Sun Nan Hu Jian Zhang 《China Communications》 SCIE CSCD 2016年第10期69-78,共10页
The problem of mobile localization for wireless sensor network has attracted considerable attention in recent years. The localization accuracy will drastically grade in non-line of sight(NLOS) conditions. In this pape... The problem of mobile localization for wireless sensor network has attracted considerable attention in recent years. The localization accuracy will drastically grade in non-line of sight(NLOS) conditions. In this paper, we propose a mobile localization strategy based on Kalman filter. The key technologies for the proposed method are the NLOS identification and mitigation. The proposed method does not need the prior knowledge of the NLOS error and it is independent of the physical measurement ways. Simulation results show that the proposed method owns the higher localization accuracy when compared with other methods. 展开更多
关键词 wireless sensor network LOCALIZAtion non-line of sight identification MITIGAtion
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CONSTRAINT VIOLATION STABILIZATION OF EULER-LAGRANGE EQUATIONS WITH NON-HOLONOMIC CONSTRAINTS 被引量:2
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作者 ZhaoWeijia PanZhenkuan ChenLiqun 《Acta Mechanica Solida Sinica》 SCIE EI 2004年第1期45-51,共7页
Two constraint violation stabilization methods are presented to solve the Euler Lagrange equations of motion of a multibody system with nonholonomic constraints. Compared to the previous works, the newly devised metho... Two constraint violation stabilization methods are presented to solve the Euler Lagrange equations of motion of a multibody system with nonholonomic constraints. Compared to the previous works, the newly devised methods can deal with more complicated problems such as those with nonholonomic constraints or redundant constraints, and save the computation time. Finally a numerical simulation of a multibody system is conducted by using the methods given in this paper. 展开更多
关键词 Euler-Lagrange equation nonholonomic constraint constraint violation stabiliza- tion redundant constraint
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