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Effect of Different Proportions of Wolffia on Growth of Procambarus clarkia in Two Community Scales 被引量:1
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作者 季鹏飞 严幸云 +1 位作者 黄成 唐建清 《Agricultural Science & Technology》 CAS 2012年第7期1583-1586,共4页
[Objective] This study aimed to examine the effect of different proportions of Wolffia on the growth of Procambarus clarkia in 2 kinds of community scales. [Method] Six proportions of baits mixed by watermeal and comm... [Objective] This study aimed to examine the effect of different proportions of Wolffia on the growth of Procambarus clarkia in 2 kinds of community scales. [Method] Six proportions of baits mixed by watermeal and commercial feed (0, 20%, 40%, 60%, 80%, and 100%) were designed to feed the Procambarus clarkia juveniles in 2 community scales to research the growth situation of the crayfish in different mixed baits. The growth differences between the minimal community and the larger community of crayfish in the same proportion of Wolffia were compared. [Result] The growth situations of crayfish in the 2 community scales at different proportions of watermeal were as follows: the body length was the longest in 60% watermeal group, and shortest in the pure watermeal group; the regularity was the best in the 20% watermeal group; no matter the minimal community or the larger community, there was no significant difference in the survival rate between different watermeal proportions. The growth situations of crayfish in the 2 community scales at specific proportion of watermeal were: the average body length of the minimal community was significantly greater than the larger community, and the survival rate also greater than the latter one, but the difference was not significant. [Conclusion] Considering all kinds of index such as growth, survival rate, regularity, the appropriate proportion of the baits mixed by watermeal and commercial feed is 40% to 60%; big community scale has significant inhibition on growth of crayfish, thus, there should be barriers when cultivating Procambarus clarkia juvenile. 展开更多
关键词 Wolffia Minimal community Larger community Mixed feed Optimum proportion
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Effects of different proportions of two Bacillus sp. on the growth performance, small intestinal morphology, caecal microbiota and plasma biochemical profile of Chinese Huainan Partridge Shank chickens 被引量:5
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作者 YANG Jia-jun QIAN Kun +3 位作者 WU Dong ZHANG Wei WU Yi-jing XU Ya-yuan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第6期1383-1392,共10页
A total of 900 one-d-old Chinese Huainan Partridge Shank chickens were randomly allocated into nine groups with five replicates of 20 each.Birds were fed with basal diet,basal diet supplemented with 150 mg kg^(–1) ... A total of 900 one-d-old Chinese Huainan Partridge Shank chickens were randomly allocated into nine groups with five replicates of 20 each.Birds were fed with basal diet,basal diet supplemented with 150 mg kg^(–1) aureomycin,basal diet supplemented with different proportions of Bacillus licheniformis and Bacillus subtilis,which was 0:1.0×10~6,2.5×10~5:7.5×10~5,3.3×10~5:6.6×10~5,5.0×10~5:5.0×10~5,6.6×10~5:3.3×10~5,7.5×10~5:2.5×10~5 and 1.0×10~6:0,respectively.The duration of the experiment was 56 d.The results indicated that dietary supplementation of 6.6×10~5:3.3×10~5 of B.lichenifornis:B.subtilis improved final body weight,increased the average daily gain,and reduced feed/gain ratio(P〈0.05).The numbers of total Lactobacillus and Bifidobacterium sp.in the caecum significantly increased,and the numbers of Escherichia coli and Salmonella sp.significantly declined compared to that of the control(P〈0.05).Intestinal villous height and villous height to crypt depth ratio of the duodenum,jejunum,and ileum were significantly higher than that of the control,and intestinal crypt depth of the duodenum and ileum was significantly lower(P〈0.05).The total antioxidant capacity,total superoxide dismutase,and glutathione peroxidase ability in plasma significantly improved,while the malondialdehyde concentration in plasma decreased(P〈0.05).Compared to the control,plasma concentrations of ammonia,uric acid and urea nitrogen and the activity of xanthine oxidase were reduced(P〈0.05).In conclusion,an inclusion of 6.6×10~5:3.3×10~5 of B.licheniformis:B.subtilis to the diet improved the growth performance,caecal microbiota,plasma biochemical profile,and significantly improved the small intestine morphology,while reducing the mortality rate. 展开更多
关键词 two-strain Bacillus proportION growth performance small intestinal morphology biochemical profile
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Mixing planting proportions in a plantation affects functional traits and biomass allocation of Cunninghamia lanceolata and Phoebe bournei seedlings 被引量:4
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作者 Meiqin Zha Youzhi Han Xiangrong Cheng 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第6期1793-1805,共13页
Functional traits of trees are significantly associated with their adaptation strategies and productivity.However,the effects of species composition and mixing proportion on the functional traits of trees grown in mix... Functional traits of trees are significantly associated with their adaptation strategies and productivity.However,the effects of species composition and mixing proportion on the functional traits of trees grown in mixed plantations have not been studied extensively.In this study,planting experiments(duration about seven months)were used to study variations in functional traits and biomass allocation of C unninghamia lanceolata(Lamb.)Hook and Phoebe bournei(Hemsley)Yang seedlings in five different mixes(0C:4P,1C:3P,1C:1P,3C:1P,and 4C:0P).Total leaf area per seedling increased in each species as its respective proportion in the mixture decreased.However,the specific leaf area decreased for P.bournei under low percent composition,and the specific leaf area for C.lanceolata differed only marginally among the plantings.The net photosynthetic rates of the two species were higher in the mixed plantings than in their corresponding monocultures,whereas the transpiration rate,stomatal conductance,and instantaneous water use efficiency were not different among the plantings.The average root length and root surface area of C.lanceolata and P.bournei were higher in the mixed plantings than in their monocultures.Specifically,root surface area of C.lanceolate and both root length and surface area of P.bournei increased significantly in the 1C:3P and 2C:2P mixed plantings.Leaf,stem,root,and total dry mass per seedling for C.lanceolata decreased with its increasing percent composition in the mixed plantings,while these variables varied less for P.bournei.The plasticity of biomass allocation was relatively low for both species.Total biomass per planting was higher in the mixed plantings than in the monocultures.Our study indicates that species composition and mixing proportion can considerably affect the functional traits of C.lanceolata and P.bournei.The increase in productivity in the mixed plantings may be partially attributed to low rates of competition between the two species,and future studies should examine the different interspecies relationships.The results of this study can be used to improve plantation productivity and ultimately increase the sustainability of tree products and help to better understand the adaptation strategies of plant coexistence. 展开更多
关键词 Mixing proportion Tree species composition Functional traits Interspecific relationship Intraspecific relationship
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Compositions,Proportions,and Equilibrium Temperature of Coexisting Two-feldspar in Crystalline Rocks 被引量:1
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作者 MA Hongwen YANG Jing +1 位作者 SU Shuangqing YAO Wengui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第3期875-881,共7页
Compositions, proportions, and equilibrium temperature of coexisting two-feldspar in crystalline rocks are of great importance to classification in petrography and interpretation of petrogenesis. Crystalline rocks are... Compositions, proportions, and equilibrium temperature of coexisting two-feldspar in crystalline rocks are of great importance to classification in petrography and interpretation of petrogenesis. Crystalline rocks are usually composed of 4-6 minerals (phases), depending on their independent chemical components and the equilibrium temperature of crystallizations. In general, number of mineral phases can be determined by the "Phase Rule". According to the mass balance principle, bulk composition of coexisting two-feldspar could be evaluated from the bulk chemistry of a rock, provided that the compositions of the coexisting mafic mineral phases containing calcium, sodium, and potassium oxides are determined, e.g., by microprobe analysis. The compositions, proportions, and temperature of two-feldspar in equilibrium can thus be simultaneously resolved numerically from bulk composition of the rock, by incorporating the activity/composition relations of the ternary feldspars with the mass balance constraints. Upon the numerical approximation method presented in this paper, better-quality, internally consistent data on feldspar group could usually be obtained, which would be expected more realistic and accurate in consideration of thermodynamic equilibria in the system of crystalline rocks, as well as bulk chemistry of a rock and the composing minerals. 展开更多
关键词 crystalline rocks mass balance principle feldspar proportion activity equation equilibrium temperature
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Exact Distribution of Difference of Two Sample Proportions and Its Inferences 被引量:1
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作者 Keshab R. Dahal Mohamed Amezziane 《Open Journal of Statistics》 2020年第3期363-374,共12页
Comparing two population proportions using confidence interval could be misleading in many cases, such </span><span style="font-family:Verdana;">as</span><span style="font-family:Ve... Comparing two population proportions using confidence interval could be misleading in many cases, such </span><span style="font-family:Verdana;">as</span><span style="font-family:Verdana;"> the sample size </span><span style="font-family:Verdana;">being</span><span style="font-family:Verdana;"> small and the test </span><span style="font-family:Verdana;">being</span><span style="font-family:Verdana;"> based on normal approximation. In this case, the only </span><span style="font-family:Verdana;">one</span><span style="font-family:Verdana;"> option that we have is to collect a large sample. Unfortunately, the large sample might not be possible. One example is a person suffering from a rare disease. The main purpose of this journal is to derive a closed formula for the exact distribution of the difference between two independent sample proportions, and use it to perform related inferences such as a confidence interval, regardless of the sample sizes and compare with the existing Wald, Agresti-Caffo </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> Score. In this journal, we have derived a closed formula for the exact distribution of the difference between two independent sample proportions. This distribution doesn’t need any </span><span style="font-family:Verdana;">requirements,</span><span style="font-family:Verdana;"> and can be used to perform inferences such </span><span style="font-family:Verdana;">as:</span><span style="font-family:Verdana;"> a hypothesis test for two population proportions, regardless of the nature of the distribution and the sample sizes. We claim </span><span style="font-family:Verdana;">that</span><span style="font-family:Verdana;"> exact distribution has the </span><span style="font-family:Verdana;">least</span><span style="font-family:Verdana;"> confidence width among Wald, Agresti-Caffo </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> Score, so it is suitable for inferences of the difference between the population proportion regardless of sample size. 展开更多
关键词 Statistical Inferences Exact Distribution Difference of Sample proportions
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Representative heights for assessing whole-tree values of cell-type proportions in Eucalyptus camaldulensis and E. globulus
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作者 Jyunichi Ohshima Kazuya Iizuka +2 位作者 Futoshi Ishiguri Shinso Yokota Toshihiro Ona 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第3期885-900,共16页
Eucalyptus camaldulensis Dehnh. and E. globulus Labill. are economically important species for wood and pulpwood materials. Representative heights for assessing whole-tree values of cell-type proportions(vessels, fibe... Eucalyptus camaldulensis Dehnh. and E. globulus Labill. are economically important species for wood and pulpwood materials. Representative heights for assessing whole-tree values of cell-type proportions(vessels, fibers, ray and axial parenchyma percentages) using increment cores were examined by analysis of within-tree variations. Pattern differences were evaluated between trees and species in both radial and axial directions by statistical data analysis(Moses test). In E. camaldulensis,within-tree variation of vessel percentage was generally higher in the upper and outer regions of the trunk. In contrast, E. globulus within-tree variation was unclear. In both species, although no clear pattern of fiber percentages was observed, within-tree variations of ray and axial parenchyma levels were higher in the lower and inner regions.Significant differences in patterns were observed in the axial variation between species for vessel percentages and in the radial variation between trees of E. camaldulensis for ray parenchyma percentages. The representative heights for assessing whole-tree cell-type proportions were 0.8 mabove the ground for E. camaldulensis and 2.8 m for E.globulus, regardless of differences in tree height and pattern of within-tree variation of cell-type proportions. 展开更多
关键词 Eucalyptus CELL-TYPE proportion Within-tree variation REPRESENTATIVE height Quality breeding
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Effects of Different Hormone Proportions on Differentiation and Regeneration of Prtmus avium L. Adventitious Buds
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作者 Xuanping HU 《Agricultural Biotechnology》 CAS 2014年第1期40-42,共3页
In order to screen the appropriate culture condition for the differentiation and regeneration of Prtmus avium L. adventitious buds, in this study, the effect of different hormone proportions on differentiation and reg... In order to screen the appropriate culture condition for the differentiation and regeneration of Prtmus avium L. adventitious buds, in this study, the effect of different hormone proportions on differentiation and regeneration of shoot tip explants were investigated using Gisela No. 5 and Gisela No. 6 as experimental materi- als. The results showed that, different hormone proportions had extremely significant effects ( P 〈0.01 ) on the differentiation rate of P. avium adventitious buds; the appropriate hormone proportions for Gisela No. 5 and Gisela No. 6 to induce dedifferentiation of adventitious buds were 6-BA 3.0 mg/L + IBA 0.5 mg/L + KT O. 1 mg/L and 6-BA 1.0 mg/L + IBA 0.5 mg/L + KT 0.2 rag/L, respectively. In addition, different hormone proportions had extremely significant effects (P 〈 0.01 ) on the regeneration coefficient and regeneration rate of P. avium adventitious buds; with the hormone proportion of 6-BA 1.0 mg/L + IBA 1.0 mg/L + KT 0.3mg/L, the number of regenerated adventitious buds reached the maximum for both varieties. 展开更多
关键词 Prtrmus avium L. Hormone proportions Adventitious buds DIFFERENTIATION
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Inferences on the Difference of Two Proportions: A Bayesian Approach
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作者 Thu Pham-Gia Nguyen Van Thin Phan Phuc Doan 《Open Journal of Statistics》 2017年第1期1-15,共15页
Let π=π1-π2 be the difference of two independent proportions related to two populations. We study the test H0:π≥0 against different alternatives, in the Bayesian context. The various Bayesian approaches use stand... Let π=π1-π2 be the difference of two independent proportions related to two populations. We study the test H0:π≥0 against different alternatives, in the Bayesian context. The various Bayesian approaches use standard beta distributions, and are simple to derive and compute. But the more general test H0:π≥η, with η>0, requires more advanced mathematical tools to carry out the computations. These tools, which include the density of the difference of two general beta variables, are presented in the article, with numerical examples for illustrations to facilitate comprehension of results. 展开更多
关键词 proportION CONVOLUTION Normal BETA BAYESIAN Critical Value Appell’s Function
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Reduction of NO_(x)emission based on optimized proportions of mill scale and coke breeze in sintering process
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作者 Zhi-gang Que Xian-bin Ai Sheng-li Wu 《International Journal of Minerals,Metallurgy and Materials》 CSCD 2021年第9期1453-1461,共9页
Reducing NO_(x) emission of iron ore sintering process in a cost effective manner is a challenge for the iron and steel industry at present.Effects of the proportion of mill scale and coke breeze on the NO_(x) emissio... Reducing NO_(x) emission of iron ore sintering process in a cost effective manner is a challenge for the iron and steel industry at present.Effects of the proportion of mill scale and coke breeze on the NO_(x) emission,strength of sinter,and sinter indexes were studied by com-bustion and sinter pot tests.Results showed that the peak value of NO concentration,total of NO emission,and fuel-N conversion rate gradu-ally decreased as the proportions of the mill scale increased because NO was reduced to N_(2) by Fe_(3)O_(4),FeO,and Fe in the mill scale.The strength of sinter reached the highest value at 8.0wt%mill scale due to the formation of minerals with low melting point.The fuel-N conver-sion rate slightly fluctuated and total NO_(x) emission significantly decreased with the decreased proportions of coke breeze because CO forma-tion and content of N element in the sintered mixture decreased.However,the sinter strength also decreased due to the decrease in the amount of the melting minerals.Furthermore,results of the sinter pot tests indicated that NO_(x) emission decreased.The sinter indexes performed well when the proportions of mill scale and coke breeze were 8.0wt%and 3.70wt%respectively in the sintered mixture. 展开更多
关键词 iron ore sinter NO_(x)emission mill scale coke breeze proportion optimization
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Partitioning Calculation Method of Short-Circuit Current for High Proportion DG Access to Distribution Network
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作者 Wei Wang Qingzhu Shao +4 位作者 Shaoliang Wang Yiwei Zhao Yuanbo Ye Duanchao Li Mengyu Wu 《Energy Engineering》 EI 2024年第9期2569-2584,共16页
Aiming at the problemthat the traditional short-circuit current calculationmethod is not applicable to Distributed Generation(DG)accessing the distribution network,the paper proposes a short-circuit current partitioni... Aiming at the problemthat the traditional short-circuit current calculationmethod is not applicable to Distributed Generation(DG)accessing the distribution network,the paper proposes a short-circuit current partitioning calculation method considering the degree of voltage drop at the grid-connected point of DG.Firstly,the output characteristics of DG in the process of low voltage ride through are analyzed,and the equivalent output model of DG in the fault state is obtained.Secondly,by studying the network voltage distribution law after fault in distribution networks under different DG penetration rates,the degree of voltage drop at the grid-connected point of DG is used as a partition index to partition the distribution network.Then,iterative computation is performed within each partition,and data are transferred between partitions through split nodes to realize the fast partition calculation of short-circuit current for high proportion DG access to distribution network,which solves the problems of long iteration time and large calculation error of traditional short-circuit current.Finally,a 62-node real distribution network model containing a high proportion of DG access is constructed onMATLAB/Simulink,and the simulation verifies the effectiveness of the short-circuit current partitioning calculation method proposed in the paper,and its calculation speed is improved by 48.35%compared with the global iteration method. 展开更多
关键词 High proportion DG short-circuit calculation low voltage ride through partition iteration
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T lymphocyte proportion in Alzheimer’s disease prognosis
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作者 Matthew Willman Gopi Patel Brandon Lucke-Wold 《World Journal of Clinical Cases》 SCIE 2024年第26期6001-6003,共3页
Bai et al investigate the predictive value of T lymphocyte proportion in Alzheimer's disease(AD)prognosis.Through a retrospective study involving 62 AD patients,they found that a decrease in T lymphocyte proportio... Bai et al investigate the predictive value of T lymphocyte proportion in Alzheimer's disease(AD)prognosis.Through a retrospective study involving 62 AD patients,they found that a decrease in T lymphocyte proportion correlated with a poorer prognosis,as indicated by higher modified Rankin scale scores.While the study highlights the potential of T lymphocyte proportion as a prognostic marker,it suggests the need for larger,multicenter studies to enhance generalizability and validity.Additionally,future research could use cognitive exams when evaluating prognosis and delve into immune mechanisms underlying AD progression.Despite limitations inherent in retrospective designs,Bai et al's work contributes to understanding the immune system's role in AD prognosis,paving the way for further exploration in this under-researched area. 展开更多
关键词 Alzheimer's disease T lymphocyte T lymphocyte proportion Alzheimer's disease prognosis Modified rankin scale Immune cell count ELECTROENCEPHALOGRAM Immune function
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Assessment of Operational Performance in a Power Generation/Selling Integrated Company Using a Dynamic Proportional Adjustment Coefficient
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作者 Jingbin Wu Hongming Yang Sheng Xiang 《Energy Engineering》 EI 2024年第11期3263-3287,共25页
Currently,the operational performance assessment system in the power market primarily focuses on power generation and electricity retail companies,lacking a system tailored to the operational characteristics of power ... Currently,the operational performance assessment system in the power market primarily focuses on power generation and electricity retail companies,lacking a system tailored to the operational characteristics of power generation/selling integrated companies.Therefore,this article proposes an assessment index system for assessing the operational performance of a power generation/selling integrated company,encompassing three dimensions:basic capacity,development potential,and external environment.A dynamic proportional adjustment coefficient is designed,along with a subjective and objective weighting model for assessment indexes based on a combined weightingmethod.Subsequently,the operational performance of an integrated company is assessed using extension theory.The results in the case study demonstrate the feasibility and effectiveness of the proposed dynamic proportional adjustment coefficient. 展开更多
关键词 Power generation/selling integrated company dynamic proportional adjustment coefficient combined weighting extension theory assessment of operational performance
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ISO International Standards—a“toolbox”of Olympic proportions for major sporting,cultural and social events 被引量:1
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作者 Alan Bryden 《China Standardization》 2008年第4期4-9,共6页
How are the winners determined in most of the events that make up the Olympic Games? Theyare,of course,the athletes who run or swim faster,jump higher,lift heavier,throw further.But how is their prowess measured? By t... How are the winners determined in most of the events that make up the Olympic Games? Theyare,of course,the athletes who run or swim faster,jump higher,lift heavier,throw further.But how is their prowess measured? By the SI (Système inter-national) International System of Units,which 展开更多
关键词 In of Olympic proportions for major sporting cultural and social events ISO International Standards TOOLBOX
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A Note on an Order Level Inventory Model with Varying Two-Phased Demand and Time-Proportional Deterioration
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作者 Sephali Mohanty Trailokyanath Singh +1 位作者 Sudhansu Sekhar Routary Chinmayee Naik 《American Journal of Operations Research》 2024年第1期59-73,共15页
The main purpose of this paper is to generalize the effect of two-phased demand and variable deterioration within the EOQ (Economic Order Quantity) framework. The rate of deterioration is a linear function of time. Th... The main purpose of this paper is to generalize the effect of two-phased demand and variable deterioration within the EOQ (Economic Order Quantity) framework. The rate of deterioration is a linear function of time. The two-phased demand function states the constant function for a certain period and the quadratic function of time for the rest part of the cycle time. No shortages as well as partial backlogging are allowed to occur. The mathematical expressions are derived for determining the optimal cycle time, order quantity and total cost function. An easy-to-use working procedure is provided to calculate the above quantities. A couple of numerical examples are cited to explain the theoretical results and sensitivity analysis of some selected examples is carried out. 展开更多
关键词 Deteriorating Items EOQ (Economic Order Quantity) INVENTORY Time-proportional Deterioration Two-Phased Demand
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Product reliability assessment based on proportional hazard degradation model 被引量:4
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作者 苏春 张烨 张恒 《Journal of Southeast University(English Edition)》 EI CAS 2010年第3期480-483,共4页
In order to evaluate the reliability of long-lifetime products with degradation data, a new proportional hazard degradation model is proposed. By the similarity between time-degradation data and stress-accelerated lif... In order to evaluate the reliability of long-lifetime products with degradation data, a new proportional hazard degradation model is proposed. By the similarity between time-degradation data and stress-accelerated lifetime, and the failure rate function of degradation data which is assumed to be proportional to the time covariate, the reliability assessment based on a proportional hazard degradation model is realized. The least squares method is used to estimate the model's parameters. Based on the failure rate of the degradation data and the proportion function of the known time, the failure rate and the reliability function under the given time and the predetermined failure threshold can be extrapolated. A long life GaAs laser is selected as a case study and its reliability is evaluated. The results show that the proposed method can accurately describe the degradation process and it is effective for the reliability assessment of long lifetime products. 展开更多
关键词 degradation data hazard function proportional hazard model reliability assessment
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Variable Structure Proportional Navigation for Homing Missile 被引量:2
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作者 宋建梅 张天桥 《Journal of Beijing Institute of Technology》 EI CAS 2000年第3期296-301,共6页
The purpose of this paper is to design control loop and guidance loop for the homing missile, to prove that the modified variable structure proportional navigation (VSPN) can be used in passive homing guidance system,... The purpose of this paper is to design control loop and guidance loop for the homing missile, to prove that the modified variable structure proportional navigation (VSPN) can be used in passive homing guidance system, and to compare the VSPN with the proportional navigation (PN). Angular rate and linear acceleration are fed back to improve the stability and robust of autopilot, VSPN and PN are compared in mathematics simulation of homing missile in attacking tanks and helicopters. The damp and the stability of the missile body are increased. The VSPN cuts down the overload of guidance phase dramatically, makes the ballistic trajectory straighter than PN and leads to smaller missdistance. The VSPN can be used for passive homing guidance system, and is especially suitable for attacking helicopter. 展开更多
关键词 homing missile variable structure proportional navigation (VSPN) proportional navigation (PN)
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Self Adjusting Feedforward Compensation Tracking Control for Proportional Valve Controlled Motor 被引量:1
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作者 彭熙伟 王渝 王向周 《Journal of Beijing Institute of Technology》 EI CAS 1999年第3期282-287,共6页
Aim Aiming at the position tracking control for valve controlled motor electrohydraulic proportional servo systems mainly driving the static load torque, the tracking performance was studied in the presence of the v... Aim Aiming at the position tracking control for valve controlled motor electrohydraulic proportional servo systems mainly driving the static load torque, the tracking performance was studied in the presence of the variable gain and deadzone. Methods On the basis of conventional composite control with the deadzone compensation method, a comprehensive control approach with the deadzone and self adjusting feedforward compensation was proposed. Results Experimental results showed that the good tracking performance was achieved for the sinusoidal and constant velocity position tracking under a wide variations of load torque. Conclusion The position tracking accuracy for valve controlled motor electrohydraulic proportional servo systems has been solved by using the comprehensive control approach with the deadzone and self adjusting feedforward compensation. 展开更多
关键词 self adjusting feedforward compensation deadzone compensation tracking control electrohydraulic proportional servo system
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The burden of upper motor neuron involvement is correlated with the bilateral limb involvement interval in patients with amyotrophic lateral sclerosis:a retrospective observational study
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作者 Jieying Wu Shan Ye +2 位作者 Xiangyi Liu Yingsheng Xu Dongsheng Fan 《Neural Regeneration Research》 SCIE CAS 2025年第5期1505-1512,共8页
Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor neurons.Early bilateral limb involvement significantly affects patients'daily lives ... Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor neurons.Early bilateral limb involvement significantly affects patients'daily lives and may lead them to be confined to bed.However,the effect of upper and lower motor neuron impairment and other risk factors on bilateral limb involvement is unclear.To address this issue,we retrospectively collected data from 586 amyotrophic lateral sclerosis patients with limb onset diagnosed at Peking University Third Hospital between January 2020 and May 2022.A univariate analysis revealed no significant differences in the time intervals of spread in different directions between individuals with upper motor neuron-dominant amyotrophic lateral sclerosis and those with classic amyotrophic lateral sclerosis.We used causal directed acyclic graphs for risk factor determination and Cox proportional hazards models to investigate the association between the duration of bilateral limb involvement and clinical baseline characteristics in amyotrophic lateral sclerosis patients.Multiple factor analyses revealed that higher upper motor neuron scores(hazard ratio[HR]=1.05,95%confidence interval[CI]=1.01–1.09,P=0.018),onset in the left limb(HR=0.72,95%CI=0.58–0.89,P=0.002),and a horizontal pattern of progression(HR=0.46,95%CI=0.37–0.58,P<0.001)were risk factors for a shorter interval until bilateral limb involvement.The results demonstrated that a greater degree of upper motor neuron involvement might cause contralateral limb involvement to progress more quickly in limb-onset amyotrophic lateral sclerosis patients.These findings may improve the management of amyotrophic lateral sclerosis patients with limb onset and the prediction of patient prognosis. 展开更多
关键词 amyotrophic lateral sclerosis bilateral limb involvement Cox proportional hazards regression model horizontal spread restricted cubic spline analysis time interval upper motor neuron vertical spread
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Precision Point to Point Control of Proportional Valve Controlled Motor with a Time Varying Load
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作者 彭熙伟 王渝 王向周 《Journal of Beijing Institute of Technology》 EI CAS 1999年第3期288-293,共6页
Aim In accordance with the positioning control for valve controlled motor electrohydraulic proportional servo systems driving the static load torque, the positioning performance was studied in the presence of the ti... Aim In accordance with the positioning control for valve controlled motor electrohydraulic proportional servo systems driving the static load torque, the positioning performance was studied in the presence of the time? varying deadzone and gain. Methods The large positioning errors caused by the time varying deadzone were significantly reduced by using the dynamic compensation method for the deadzone; and the large overshoot caused by the time varying gain were dramatically reduced by using the three section intelligent control schemes. Results Experimental results demonstrated that the positioning performance of rapid response, high accuracy and smaller or even no overshoot was achieved under a wide variations of load torque. Conclusion The good positioning performance for valve controlled motor servo systems has been achieved in the presence of the time varying deadzone and gain. 展开更多
关键词 fuzzy control intelligent control deadzone compensation point to point control electrohydraulic proportional servo system
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全身炎症反应指数与缺血性脑卒中患者复发风险的关联性研究
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作者 刘祖婷 徐明欢 +6 位作者 杨学智 莫佳丽 刘星雨 杜慧杰 张慧琴 易应萍 况杰 《中国全科医学》 CAS 北大核心 2025年第5期541-547,共7页
背景全身炎症反应指数(SIRI)是一种较新的炎症生物标志物,其与缺血性脑卒中患者复发的关系尚不明确。目的探讨SIRI水平与缺血性脑卒中患者1年内复发的关联性。方法选取2019年3月—2021年3月在南昌大学第一附属医院、南昌大学第二附属医... 背景全身炎症反应指数(SIRI)是一种较新的炎症生物标志物,其与缺血性脑卒中患者复发的关系尚不明确。目的探讨SIRI水平与缺血性脑卒中患者1年内复发的关联性。方法选取2019年3月—2021年3月在南昌大学第一附属医院、南昌大学第二附属医院、南昌市第二医院和南昌市第三医院住院且确诊为缺血性脑卒中的患者作为研究对象进入队列,并对其随访1年。收集患者入院后48 h内的基线信息、随访过程中的缺血性脑卒中复发情况。采用Cox比例风险回归模型、限制性立方样条、亚组分析探讨SIRI与缺血性脑卒中患者1年内复发之间的关联性。结果本研究纳入了1023例患者,在1年随访期间共107例(10.46%)复发。多因素Cox比例风险回归模型分析结果显示,在调整变量后,SIRI升高是缺血性脑卒中复发的危险因素(HR=1.06,95%CI=1.01~1.10,P<0.05)。将SIRI按四分位数分类时,与Q1亚组(256例)相比,Q4亚组(256例)有较高的缺血性脑卒中复发风险(HR=1.80,95%CI=1.08~3.00,P<0.05)。限制性立方样条分析结果显示,SIRI与缺血性脑卒中复发风险呈J型的剂量-反应关系(PNonlinear=0.025)。进一步按性别、年龄、既往脑卒中、入院时美国国立卫生研究院卒中量表(NIHSS)评分分层进行亚组分析,结果显示,SIRI和入院时NIHSS评分分层存在交互作用(P<0.001),在NIHSS评分为0~1分时,SIRI(HR=1.25,95%CI=1.04~1.51,P=0.020)与缺血性脑卒中复发存在相关关系;在NIHSS评分为5~15分时,SIRI(HR=1.20,95%CI=1.12~1.28,P<0.001)与缺血性脑卒中复发存在相关关系;在上述评分区间SIRI升高与缺血性脑卒中复发风险增加有关。结论较高的SIRI与缺血性脑卒中复发风险增加明显相关。在SIRI与缺血性脑卒中复发之间观察到J型关联,且在NIHSS评分为0~1、5~15分的缺血性脑卒中患者中,SIRI升高与缺血性脑卒中复发风险增加有关。 展开更多
关键词 缺血性卒中 全身炎症反应指数 复发 队列研究 COX比例风险回归模型
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