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Factors affecting relative humidity during wood vacuum drying 被引量:1
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作者 肖辉 蔡英春 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第2期165-167,I0004,共4页
Effects of pressure and temperature in the chamber during vacuum drying on the relative humidity and evaporation of wood surface were investigated by using the vacuum chamber. The setting temperature during vacuum dry... Effects of pressure and temperature in the chamber during vacuum drying on the relative humidity and evaporation of wood surface were investigated by using the vacuum chamber. The setting temperature during vacuum drying included dry-bulb temperature ta, the wet-bulb temperature tw and the temperature difference between the air in the vacuum chamber and the cooling water in the condenser. Results indicated that relative humidity during vacuum drying was affected by the dry-bulb temperature td, the wet-bulb temperature tw and the temperature difference between the air in the vacuum chamber and the water in the condenser. Relative humidity of wood decreased with the increase in temperature at the given temperature of the water in the condenser. The relative humidity was affected slightly by pressure in the vacuum chamber pA, and it decreased from 70% to 65% with pA increased from 50 kPa to 101 kPa. Moreover, there was nearly no evaporation under the vacuum without external heating. 展开更多
关键词 influencing factors radio frequency relative humidity wood vacuum drying
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Recurrent acute pancreatitis and its relative factors 被引量:8
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作者 WeiZhang Hong-ChaoShan YanGu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第19期3002-3004,共3页
AIM: To evaluate the causes and the relative factors of recurrent acute pancreatitis.METHODS: From 1997 to 2000, acute pancreatitis relapsed in 77 of 245 acute pancreatitis patients. By reviewing the clinical treatmen... AIM: To evaluate the causes and the relative factors of recurrent acute pancreatitis.METHODS: From 1997 to 2000, acute pancreatitis relapsed in 77 of 245 acute pancreatitis patients. By reviewing the clinical treatment results and the follow-up data, we analyzed the recurrent factors of acute pancreatitis using univariate analysis and multivariate analysis.RESULTS: Of the 245 acute pancreatitis patients, 77 were patients with recurrent acute pancreatitis. Of them, 56 patients relapsed two times, 19 relapsed three times, each patient relapsed three and four times. Forty-seven patients relapsed in hospital and the other 30 patients relapsed after discharge. Eighteen patients relapsed in 1 year, eight relapsed in 1-3 years, and four relapsed after 3 years. There were 48 cases of biliary pancreatitis, 3 of alcohol pancreatitis, 5 of hyperlipidemia pancreatitis, 21 of idiopathic pancreatitis. Univariate analysis showed that the patients with local complications of pancreas, obstructive jaundice and hepatic function injury were easy to recur during the treatment period of acute pancreatitis (P = 0.022<0.05, P = 0.012<0.05 and P = 0.002<0.05, respectively). Multivariate analysis showed that there was no single factor related to recurrence. Of the 47 patients who had recurrence in hospital, 16 had recurrence in a fast period, 31 after refeeding. CONCLUSION: Acute pancreatitis is easy to recur even during treatment. The factors such as changes of pancreas structure and uncontrolled systemic inflammatory reaction are responsible for the recurrence of acute pancreatitis. Early refeeding increases the recurrence of acute pancreatitis. Defining the etiology is essential for reducing the recurrence of acute pancreatitis. 展开更多
关键词 Acute pancreatitis relative factors
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Integrating Factors and Conservation Theorems of Nonholonomic Dynamical System of Relative Motion 被引量:2
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作者 QIAO Yong-Fen ZHAO Shu-Hong LI Ren-Jie 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2期217-220,共4页
The integrating factors and conservation theorems of nonholonomic dynamical system of relative motion are studied. First, the dynamical equations of relative motion of system are written. Next, the definition of integ... The integrating factors and conservation theorems of nonholonomic dynamical system of relative motion are studied. First, the dynamical equations of relative motion of system are written. Next, the definition of integrating factors is given, and the necessary conditions for the existence of the conserved quantities are studied in detail. Then, the conservation theorem and its inverse of system are established. Finally, an example is given to illustrate the application of the result. 展开更多
关键词 nonholonomic system relative motion integrating factor conservation theorem
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Spatial-temporal characteristics and influencing factors of relative humidity in arid region of Northwest China during 1966–2017 被引量:1
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作者 CHEN Ditao LIU Wenjiang +3 位作者 HUANG Farong LI Qian Friday UCHENNAOCHEGE LI Lanhai 《Journal of Arid Land》 SCIE CSCD 2020年第3期397-412,共16页
Playing an important role in global warming and plant growth,relative humidity(RH)has profound impacts on production and living,and can be used as an integrated indicator for evaluating the wet-dry conditions in the a... Playing an important role in global warming and plant growth,relative humidity(RH)has profound impacts on production and living,and can be used as an integrated indicator for evaluating the wet-dry conditions in the arid and semi-arid area.However,information on the spatial-temporal variation and the influencing factors of RH in these regions is still limited.This study attempted to use daily meteorological data during 1966–2017 to reveal the spatial-temporal characteristics of RH in the arid region of Northwest China through rotated empirical orthogonal function and statistical analysis method,and the path analysis was used to clarify the impact of temperature(T),precipitation(P),actual evapotranspiration(ETa),wind speed(W)and sunshine duration(S)on RH.The results demonstrated that climatic conditions in North Xinjiang(NXJ)was more humid than those in Hexi Corridor(HXC)and South Xinjiang(SXJ).RH had a less significant downtrend in NXJ than that in HXC,but an increasingly rising trend was observed in SXJ during the last five decades,implying that HXC and NXJ were under the process of droughts,while SXJ was getting wetter.There was a turning point for the trend of RH in Xinjiang,which occurred in 2000.Path analysis indicated that RH was negatively correlated to T,ETa,W and S,but it increased with increase of P.S,T and W had the greatest direct effects on RH in HXC,NXJ and SXJ,respectively.ETa was the factor which had the greatest indirect effect on RH in HXC and NXJ,while T was the dominant factor in SXJ. 展开更多
关键词 relative humidity spatial-temporal characteristics path analysis influencing factor arid region
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Canonical Correlation Factors Causing the Formation of Accumulated Sand-belts along the Oasis Fringe in Hexi Corridor
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作者 Chang Zhaofeng Wang Qiangqiang +7 位作者 Zhang Jianhui Tang Jinnian Zhu Shujuan Fan Baoli Zhang Dabiao Liu Shizeng Zhang Guozhong Li Aide 《Animal Husbandry and Feed Science》 CAS 2014年第5期279-284,共6页
Accumulated sand-belts refer to those formed along the oasis fringe,especially at the upwind location,due to the accumulation of sand blocked by farmland windbreak. In the 60 years since the foundation of new China,a ... Accumulated sand-belts refer to those formed along the oasis fringe,especially at the upwind location,due to the accumulation of sand blocked by farmland windbreak. In the 60 years since the foundation of new China,a lot of trees have been planted for desertification combating in northwest and north China,thus,accumulated sand-belts were formed at the upwind location. The formation and the ecological effects of the accumulated sand-belts along the oasis fringe is a new scientific concern. To study the formation causes of these belts in Hexi corridor,21 samples were selected,and the height / width of the belts,as well as the vegetation,soil,soil moisture and climatic factors were investigated. This paper analyzed the correlation between the height / width of the belts and the vegetation,soil,soil moisture and climatic factors using the methods of variance analysis,correlation analysis and canonical correlation analysis. The results indicate that: the accumulated sand-belts take a trend of being high and wide in the east whereas low and narrow in the west,and most of the parts tend to be stable; the species on the belts are dominated by Tamarix austromongolica,the vegetation cover and the pure vegetation cover of different dominant species on the leeward slope of the accumulated sand-belts vary significantly. The canonical correlation analysis shows that: the height and width of accumulated sand-belt is the interaction of precipitation,distance to the sand source,leeward vegetation cover and annual average wind speed. Moreover,the height of accumulated sand-belts are negatively correlated to the soil moisture at the depth of 30- 50 cm,air humidity and leeward vegetation cover,and the width of the belts is also negatively correlated with the distance to the sand source. The ecological effects of the accumulated sand-belts are both positive( stopping sands from moving into farmland,protective role as an obstacle)and negative( when the belts decay and activate one day,they will become the new sand sources). At present,there are no signs showing the negative effects of the belts. The ecological effects of the accumulated sand-belts are: firstly the protective role as an obstacle,and secondly to intercept and reduce the sands moving into farmlands. 展开更多
关键词 Height of accumulated sand-belt Width of accumulated sand-belt Climatic and environmental factors Canonical correlation factors Ecological effects Hexi of Gansu
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Factors affecting relative humidity during wood vacuum drying
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作者 XIAO Hui, CAI Ying-chun Key Laboratory of Bio-based Material Science and Technology, Northeast Forestry University, Harbin 150040, P.R China 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第A2期165-167,共3页
Effects of pressure and temperature in the chamber during vacuum drying on the relative humidity and evaporation of wood surface were investigated by using the vacuum chamber.The setting temperature during vacuum dryi... Effects of pressure and temperature in the chamber during vacuum drying on the relative humidity and evaporation of wood surface were investigated by using the vacuum chamber.The setting temperature during vacuum drying included dry-bulb temperature td, the wet-bulb temperature tw and the temperature difference between the air in the vacuum chamber and the cooling water in the condenser.Results indicated that relative humidity during vacuum drying was affected by the dry-bulb temperature td, the wet-bulb temperature tw and the temperature difference between the air in the vacuum chamber and the water in the condenser.Relative humidity of wood decreased with the increase in temperature at the given temperature of the water in the condenser.The relative humidity was affected slightly by pressure in the vacuum chamber pA, and it decreased from 70% to 65% with pA increased from 50 kPa to 101 kPa.Moreover, there was nearly no evaporation under the vacuum without external heating. 展开更多
关键词 influencing factors radio frequency relative humidity wood vacuum drying
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Multiplet relative location approach and waveform correlation correction and their application
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作者 白玲 张天中 张宏智 《Acta Seismologica Sinica(English Edition)》 CSCD 2003年第6期606-615,共10页
The theory and method of relative location technique were described in the paper. The travel-time difference equa-tions for five phases (Pg, Sg, P11, S11 and Pn) were given. By using the multiplet relative location ap... The theory and method of relative location technique were described in the paper. The travel-time difference equa-tions for five phases (Pg, Sg, P11, S11 and Pn) were given. By using the multiplet relative location approach and wave correlation correction, the aftershock cluster of the Shunyi earthquake occurred on December 16, 1996 was relocated. The depth calculation was constrained by using multiple seismic phases. The relocation results were compared with that from traditional absolute location techniques. 展开更多
关键词 multiplet relative location approach waveform correlation correction P11 S11 Pn Shunyi earthquake
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Analysis of Short-Shoot Fuji Apple Tree Structure and Correlative Factors
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作者 Jie HAO Xiangmin SUO +4 位作者 Xueying LI Liang WEI Xinmin YAN Xian’ge WANG Jianzhong FENG 《Asian Agricultural Research》 2017年第6期86-88,共3页
In order to clarify the correlation between short-shoot Fuji apple tree structure and different factors under different trimming and pruning modes,we investigate the trunk taperingness of free-spindle short-shoot Fuji... In order to clarify the correlation between short-shoot Fuji apple tree structure and different factors under different trimming and pruning modes,we investigate the trunk taperingness of free-spindle short-shoot Fuji and slender-spindle short-shoot Fuji,respectively,as well as the total thickness,average thickness,total length and average length of small main branches in the standard demonstration apple garden in Xingtang County of Hebei Province. By SPSS analysis,we study the correlation between trunk taperingness of trees with different shapes and the growth indices of their small main branches. The results show that the trunk taperingness of free-spindle short-shoot Fuji apple is negatively correlated with the total thickness,average thickness,total length and average length of small main branches,but the correlation is not significant; the trunk taperingness of slender-spindle short-shoot Fuji apple is negatively correlated with the total thickness but positively correlated with other factors,and the correlation with average length reaches a significant level. The results of this study can provide a scientific basis for guiding the high-density dwarf rootstock short-shoot Fuji apple tree trimming technology. 展开更多
关键词 Short-shoot Fuji Tree structure Analysis of correlative factors
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Blood Pressure Patterns and Factors Associated with Relative Hypertension among Steady State Sickle Cell Disease Patients in Kinshasa, Democratic Republic of the Congo: A Cross-Sectional Study
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作者 P. I. Mboliasa F. B. Lepira +14 位作者 J. R. Makulo A. Nkodila E. K. Sumaili J. B. Bukabau V. M. Mokoli A. L. Longo C. V. Zinga F. M. P. Kanjingulu Y. M. Nlandu Y. M. Engole M. M. Mukendi E. M. Kadima C. K. Ilunga P. M. Ekulu N. M. N. Nseka 《World Journal of Cardiovascular Diseases》 2018年第3期217-228,共12页
Background: Although systemic hypertension is rarely seen in steady state sickle cell disease (SCD), relative hypertension has been reported to be associated with an increased risk of cardiovascular and renal complica... Background: Although systemic hypertension is rarely seen in steady state sickle cell disease (SCD), relative hypertension has been reported to be associated with an increased risk of cardiovascular and renal complications. Objective: To determine the prevalence of BP patterns and assess factors associated with relative hypertension insickle cell anemia (SCA) adult patients. Methods: Clinical data and office BP were obtained from 103 consecutive steady-state SCA adult patients (mean age 26 ± 7.9 years, 66% females, 22.3% on hydroxyurea) attending four healthcare centers providing SCD-specific care in Kinshasa. Seated BP was measured using an automated electronic device. Three consecutive blood pressure measurements were taken with 2 minutes interval between readings and the average of the 2 last readings was considered for the analyses. Normal BP, relative hypertension and systemic hypertension were defined as BP 120/70 mmHg, 120 - 139/70 - 89 mmHg and ≥140/90 mmHg, respectively. Results: Normal BP, relative hypertension and systemic hypertension were observed in 56 (54%), 43(42%) and 4 (4%) of SCA patients, respectively. In multivariate analysis, factors associated with relative hypertension were leg ulcer (aOR 2.05;95%CI 1.77 - 5.18;p = 0.016), central obesity (aOR 3.32;95%CI 1.28 - 6.24;p = 0.001), smoking (aOR 5.02;95%CI 1.51 - 9.50;p = 0.017), and microalbumiuria (aOR 3.44;95%CI 1.44 - 5.76;p = 0.035). Conclusion: Relative hypertension was a common finding in the present case series and associated with traditional cardiovascular risk factor as well as factors specific to SCD highlighting the need for measures to prevent its progression towards systemic hypertension and associated cardiovascular and renal disease. 展开更多
关键词 relative HYPERTENSION Prevalence Associated factors SICKLE Cell Anemia Black AFRICANS
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Analysis on Factors Causing Project Delays in Road and Highways Sector in India Using Relative Ranking Index Technique
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作者 Siddesh K.Pai Neeraj Anand Ankur Mittal 《Journal of Construction Research》 2021年第2期43-48,共6页
On-time completion of road infrastructure projects is a critical goal.When projects were not completed on schedule and real construction progress is slower than expected,the inconvenience and disruption to business ac... On-time completion of road infrastructure projects is a critical goal.When projects were not completed on schedule and real construction progress is slower than expected,the inconvenience and disruption to business access increases.On time completion is linked to economic and social welfare,as well as safety.Construction delays continue to be a typical occurrence,despite the need of prompt completion.A literature study is conducted in this context in order to learn more about the causes and factors that contribute to delays.Following a thorough review of the literature,it was determined that a questionnaire survey is the most effective and trustworthy way for gathering information about the causes and quantifying delays caused by emergent factors.The Relative Importance Index(RII)method was used to analyze the data,and the reasons for the delay were prioritized according to their importance.This study focuses on the emergent concerns/causes and reasons of concern in road infrastructure projects,as well as how to priorities these issues sequentially during the planning stage.This study survey can assist construction companies doing business in India in understanding the essential or sensitive issues that require special attention in order to conduct their businesses smoothly in this country while employing appropriate project management practices. 展开更多
关键词 relative importance index Issues of concern Delay factors Road Construction projects
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Effects of general anesthesia on coagulation function, stress response and other correlation factors in patients undergoing abdominal operation
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作者 Yong Li Ling Zhao Jin-Yu Duan 《Journal of Hainan Medical University》 2018年第23期25-29,共5页
Objective:To study the effects of general anesthesia on coagulation function, stress response and other correlation factors in patients undergoing abdominal operation.Methods: To select 94 cases of patients undergoing... Objective:To study the effects of general anesthesia on coagulation function, stress response and other correlation factors in patients undergoing abdominal operation.Methods: To select 94 cases of patients undergoing abdominal operation in our hospital from February 2016 to April 2018, divided into the control group and observation group, 47 cases in each group. On the basis of the same pre-processing, the patients in the control group were given epidural anesthesia, and the patients in the observation group received general anesthesia, to detect and compare the coagulation function, stress response and other correlation factors.Results:At T1, the levels of coagulation function (D-Dimer, APTT, PT, PLT), stress response (COR, ACTH, CRP, ET-1) and other correlation factors (IL-23, IL-32, M-CSF, PRL, PCT, NO, TNF-α) between the two groups had no statistical difference (P>0.05). At T2 and T3, the levels of coagulation function(D-Dimer), stress response (COR, ACTH, CRP, ET-1) and other correlation factors (IL-23, IL-32, M-CSF, PRL, PCT, NO, TNF-α) between the two groups had statistical difference (P<0.05).Conclusion:Application of general anesthesia in abdominal endoscopic operation, there was no significant change in coagulation function compared with epidural anesthesia, it could maintain stable coagulation function, but it had a better stabilizing effect on stress response index and other correlation factor such as IL-23, IL-32, M-CSF, PRL, PCT, NO and TNF-α, it was worthy of further clinical study. 展开更多
关键词 ABDOMINAL operation General ANESTHESIA COAGULATION function Stress response correlation FACTOR
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Identification of protein targets for the antidepressant effects of Kai-Xin-San in Chinese medicine using isobaric tags for relative and absolute quantitation 被引量:4
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作者 Xian-Zhe Dong Dong-Xiao Wang +3 位作者 Tian-Yi Zhang Xu Liu Ping Liu Yuan Hu 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第2期302-310,共9页
Kai-Xin-San consists of Ginseng Radix, Polygalae Radix, Acori Tatarinowii Rhizoma, and Poria at a ratio of 3:3:2:2. Kai-Xin-San has been widely used for the treatment of emotional disorders in China. However, no studi... Kai-Xin-San consists of Ginseng Radix, Polygalae Radix, Acori Tatarinowii Rhizoma, and Poria at a ratio of 3:3:2:2. Kai-Xin-San has been widely used for the treatment of emotional disorders in China. However, no studies have identified the key proteins implicated in response to Kai-Xin-San treatment. In this study, rat models of chronic mild stress were established using different stress methods over 28 days. After 14 days of stress stimulation, rats received daily intragastric administrations of 600 mg/kg Kai-Xin-San. The sucrose preference test was used to determine depression-like behavior in rats, while isobaric tags were used for relative and absolute quantitation-based proteomics to identify altered proteins following Kai-Xin-San treatment. Kai-Xin-San treatment for 2 weeks noticeably improved depression-like behaviors in rats with chronic mild stress. We identified 33 differentially expressed proteins: 7 were upregulated and 26 were downregulated. Functional analysis showed that these differentially expressed proteins participate in synaptic plasticity, neurodevelopment, and neurogenesis. Our results indicate that Kai-Xin-San has an important role in regulating the key node proteins in the synaptic signaling network, and are helpful to better understand the mechanism of the antidepressive effects of Kai-Xin-San and to provide objective theoretical support for its clinical application. The study was approved by the Ethics Committee for Animal Research from the Chinese PLA General Hospital(approval No. X5-2016-07) on March 5, 2016. 展开更多
关键词 BRAIN-DERIVED neurotrophic factor signal pathway depression ISOBARIC tags for relative and absolute quantitation Kai-Xin-San neurogenesis protein network proteomics analysis synaptic plasticity traditional Chinese medicine
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Multi-fractal Behaviors of Relative Humidity over China 被引量:2
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作者 GAO Li-Hao FU Zun-Tao 《Atmospheric and Oceanic Science Letters》 CSCD 2013年第2期74-78,共5页
The multi-fractal ity over China are studied behaviors of relative humid using the multi-fractal de trended fluctuation analysis (DFA) method. Three multi fractal parameters (the spectrum width Aa, the asymmetry Aa... The multi-fractal ity over China are studied behaviors of relative humid using the multi-fractal de trended fluctuation analysis (DFA) method. Three multi fractal parameters (the spectrum width Aa, the asymmetry Aaas, and the long-range correlation exponent a0) of the singularity spectrum are introduced to quantify the multi-fractal behaviors. The results show that multi-frac tality exists in daily humidity records over most stations in China and is mainly due to the broad distribution of the probability density of the sequence values. Strong multi fractal behaviors over some stations in the Yunnan, Guangdong, and Inner Mongolia provinces are obvious. These behaviors are mainly caused by different long range correlations between large and small fluctuations. The asymmetry of the singularity of relative humidity records is weak, except for a small number of stations in the far east and west of China, where the singularity spec trum is left-skewed. Finally, the long-range correlations in North China are stronger than those in South China, which indicates better predictability in North China. By studying the parameters of the multi-fractal spectrum, various data of long-range power law correlations of the relative humidity records are obtained, which may pro vide theoretical support for climate prediction. 展开更多
关键词 long-range correlation scaling exponent MULTI-FRACTAL multi-fractal detrended fluctuation analysisCitation: Gao L.-H. and Z.-T. Fu 2013: Multi-fractalbehaviors of relative humidity over China Atmos. Oce-anic Sci. Lett. 6 74-78.
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Parametric message passing-based relative navigation in joint tactical information distribution system 被引量:1
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作者 Nan Wu Bin Li +2 位作者 Hua Wang Liang Hou Jingming Kuang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第1期81-89,共9页
Relative navigation is a key feature in the joint tactical information distribution system(JTIDS).A parametric message passing algorithm based on factor graph is proposed to perform relative navigation in JTIDS.Firs... Relative navigation is a key feature in the joint tactical information distribution system(JTIDS).A parametric message passing algorithm based on factor graph is proposed to perform relative navigation in JTIDS.First of all,the joint posterior distribution of all the terminals' positions is represented by factor graph.Because of the nonlinearity between the positions and time-of-arrival(TOA) measurement,messages cannot be obtained in closed forms by directly using the sum-product algorithm on factor graph.To this end,the Euclidean norm is approximated by Taylor expansion.Then,all the messages on the factor graph can be derived in Gaussian forms,which enables the terminals to transmit means and covariances.Finally,the impact of major error sources on the navigation performance are evaluated by Monte Carlo simulations,e.g.,range measurement noise,priors of position uncertainty and velocity noise.Results show that the proposed algorithm outperforms the extended Kalman filter and cooperative extended Kalman filter in both static and mobile scenarios of the JTIDS. 展开更多
关键词 joint tactical information distribution system(JTIDS) relative navigation parametric message passing factor graph.
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A new calculation approach of wellbore separation factor based on the relative position of adjacent wells
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作者 HONG Difeng TANG Xueping +3 位作者 GAO Wenkai MAO Weimin WANG Peng LIU Ke 《Petroleum Exploration and Development》 2020年第1期196-203,共8页
As the current calculation methods for wellbore separation factor have some deficiencies, we propose and analyze a new calculation approach for wellbore separation factor based on the relative position of adjacent wel... As the current calculation methods for wellbore separation factor have some deficiencies, we propose and analyze a new calculation approach for wellbore separation factor based on the relative position of adjacent wellbores, named as relative position method for short. Based on the trajectory error ellipsoid model of single wellbore, the error ellipsoids model of adjacent wellbore was derived considering the correlation of trajectory errors between adjacent wells. Furthermore, the calculation formula of the separation factor based on relative position of adjacent wellbore was derived and solved with the conjugate gradient algorithm. Case study shows that the new approach is more precise and higher in applicability than the ellipsoid scaling method and the minimum distance method, it can evaluate the state of well collision more reasonably. By doing batch calculation with the new method and following the criterion of well collision avoidance, the permissible ranges of key parameters in the well design can be worked out quickly. This method has good application in the design of cluster wells and directional wells. 展开更多
关键词 wellhole separation factor wellhole COLLISION AVOIDANCE relative wellbores error CONJUGATE gradient algorithm cluster WELLS
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Assessment of Dependent Performance Shaping Factors in SPAR-H Based on Pearson Correlation Coefficient 被引量:1
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作者 Xiaoyan Su Shuwen Shang +2 位作者 Zhihui Xu Hong Qian Xiaolei Pan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1813-1826,共14页
With the improvement of equipment reliability,human factors have become the most uncertain part in the system.The standardized Plant Analysis of Risk-Human Reliability Analysis(SPAR-H)method is a reliable method in th... With the improvement of equipment reliability,human factors have become the most uncertain part in the system.The standardized Plant Analysis of Risk-Human Reliability Analysis(SPAR-H)method is a reliable method in the field of human reliability analysis(HRA)to evaluate human reliability and assess risk in large complex systems.However,the classical SPAR-H method does not consider the dependencies among performance shaping factors(PSFs),whichmay cause overestimation or underestimation of the risk of the actual situation.To address this issue,this paper proposes a new method to deal with the dependencies among PSFs in SPAR-H based on the Pearson correlation coefficient.First,the dependence between every two PSFs is measured by the Pearson correlation coefficient.Second,the weights of the PSFs are obtained by considering the total dependence degree.Finally,PSFs’multipliers are modified based on the weights of corresponding PSFs,and then used in the calculating of human error probability(HEP).A case study is used to illustrate the procedure and effectiveness of the proposed method. 展开更多
关键词 Reliability evaluation human reliability analysis SPAR-H performance shaping factors DEPENDENCE pearson correlation analysis
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Interlingual Factors in Chinese College Students' Acquisition of English Relative Clauses 被引量:1
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作者 金晓玲 乔梦锋 《Chinese Journal of Applied Linguistics》 2010年第1期110-126,128,共18页
语言研究者曾从不同角度研究了英语关系从句的习得。目前研究者普遍认为:关系从句的习得由三方面的因素决定——语际、语内和语言普遍性。本研究旨在探讨其中的一个重要因素——语际因素。以英汉关系从句形成策略为基础,本研究提出了三... 语言研究者曾从不同角度研究了英语关系从句的习得。目前研究者普遍认为:关系从句的习得由三方面的因素决定——语际、语内和语言普遍性。本研究旨在探讨其中的一个重要因素——语际因素。以英汉关系从句形成策略为基础,本研究提出了三个问题及三个相应的假设,并以112名中国大学生为研究对象,以三项测试(写作、选择题以及语法判断题)为研究手段,从语际方面对中国大学生英语关系从句的习得进行了试验性的研究。利用社会科学统计软件(SPSS),本文对研究结果进行了分析,研究发现:中国大学生英语关系从句输出不足,并且在使用方面犯有一些由语际因素所造成的错误。针对以上研究结果,本文为今后的教学和研究提出了建议。 展开更多
关键词 interlingual factors English relative clauses Chinese college students underproduction ERRORS
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Relative Broken Family Sensitivity
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作者 Zhuo Wei LIU Tao YU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2024年第9期2297-2306,共10页
Letπ:(X,T)→(Y,S)be a factor map between two topological dynamical systems,and F_(a) Furstenberg family of Z.We introduce the notion of relative broken F-sensitivity.Let Fs(resp.Fpubd,Finf)be the families consisting ... Letπ:(X,T)→(Y,S)be a factor map between two topological dynamical systems,and F_(a) Furstenberg family of Z.We introduce the notion of relative broken F-sensitivity.Let Fs(resp.Fpubd,Finf)be the families consisting of all syndetic subsets(resp.positive upper Banach density subsets,infinite subsets).We show that for a factor mapπ:(X,T)→(Y,S)between transitive systems,πis relatively broken F-sensitive for F=Fs or Fpubd if and only if there exists a relative sensitive pair which is an F-recurrent point of(R_(π),T^((2)));is relatively broken Finf-sensitive if and only if there exists a relative sensitive pair which is not asymptotic.For a factor mapπ:(X,T)→(Y,S)between minimal systems,we get the structure of relative broken F-sensitivity by the factor map to its maximal equicontinuous factor. 展开更多
关键词 relative sensitivity recurrent points Furstenberg family relative sensitive pairs maximal equicontinuous factor
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Correlation Analysis between Fruit Cracking and Influencing Factors in Apricot 被引量:3
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作者 聂国伟 李凯 +7 位作者 田永强 戴桂林 张晓萍 杨晓华 宋永宏 李静江 赵武娟 吕景丽 《Agricultural Science & Technology》 CAS 2017年第11期2001-2005,2013,共6页
In this study, 14 representative apricot cultivars in the production were selected as the experimental materials, and their fruit cracking characteristics, as well as the correlations between fruit cracking and influe... In this study, 14 representative apricot cultivars in the production were selected as the experimental materials, and their fruit cracking characteristics, as well as the correlations between fruit cracking and influencing factors (e.g., pedcarp structure, mineral elements contents, DW/FW ratio and soluble sugar content) were analyzed to provide some reference for systematic study on fruit cracking mecha- nism of apricot. The results showed the cultivars with small orderly-and compactlyarranged epidermal cells were difficult to crack, while the cultivars with big disorderly-and loosely-arranged epidermal cells were easy to crack. There was no significant correlation between pericarp thickness and cracking index. The correlations between cracking and mineral elements contents of apricot fruit were in the order as Ca 〉 Zn 〉 Mn 〉 Fe 〉 K 〉 Mg 〉 Cu. The cracking index of apricot fruit was significantly negatively correlated with Ca content, was weakly correlated with Zn and Mn contents, and was uncorrelated with Fe, K, Mg and Cu contents. Ca deficiency was the main factor affecting the fruit cracking in apricot. Under the same conditions, the higher the water content is, the lower the cracking index is; and the higher the soluble sugar content is, the higher the cracking index is. 展开更多
关键词 APRICOT Influencing factors CRACKING correlation analysis
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Research on the Correlation between Meteorological Factors and Flue-cured Tobacco Chemical Components in Different Altitudes of Lincang Region 被引量:1
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作者 王娜 赵正雄 +2 位作者 白羽祥 李世琛 陈泽 《Agricultural Science & Technology》 CAS 2015年第3期593-599,共7页
In this study, the relationship between major meteorological factors and tobacco chemical components in different altitudes of Yongde County, Lincang Region of Yunnan Province was studied using correlation analysis an... In this study, the relationship between major meteorological factors and tobacco chemical components in different altitudes of Yongde County, Lincang Region of Yunnan Province was studied using correlation analysis and path analysis methods.The results showed that there was a difference on meteorological factors in different altitudes, causing different impacts on chemical components of flue-cured tobacco; contents of nicotine and total nitrogen decreased with the rising of altitude, conversely, total sugar and reducing sugar contents increased with the rising trend of altitude, and the differences on the contents of potassium (K) and chlorine(CI), and the ratio of K to CI in different altitudes were not significant, at the altitude of 1 250-1 450 m, each chemical component indicator was better. The correlation between main meteorological factors and conventional chemical components of tobacco leaves was as follows: contents of reducing sugar and total sugar increased with the increase of rainfall and relative humidity, and decreased with the increase of sunshine duration; nicotine content increased with the increase of accumulated temperature and sunshine duration; total nitrogen (N) content increased with the increase of daily mean temperature and accumulated temperature; sugar-alkali ratio increased with the increase of rainfall. Path analysis showed that the direct effect of sunshine duration on reducing sugar and total sugar of tobacco leaves was faint, but the indirect effect was obvious; meanwhile, the direct and indirect effects of it on nicotine and total N were the greatest. 展开更多
关键词 ALTITUDE Meteorological factors . Chemical components correlation anal- ysis Path analysis
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