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Uniquely Decomposable Constellation Group-Based Sparse Vector Coding for Short Packet Communications
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作者 Xuewan Zhang Hongyang Chen +3 位作者 Di Zhang Ganyu Qin Battulga Davaasambuu Takuro Sato 《China Communications》 SCIE CSCD 2023年第5期119-134,共16页
Sparse vector coding(SVC)is emerging as a potential technology for short packet communications.To further improve the block error rate(BLER)performance,a uniquely decomposable constellation group-based SVC(UDCG-SVC)is... Sparse vector coding(SVC)is emerging as a potential technology for short packet communications.To further improve the block error rate(BLER)performance,a uniquely decomposable constellation group-based SVC(UDCG-SVC)is proposed in this article.Additionally,in order to achieve an optimal BLER performance of UDCG-SVC,a problem to optimize the coding gain of UDCG-based superimposed constellation is formulated.Given the energy of rotation constellations in UDCG,this problem is solved by converting it into finding the maximized minimum Euclidean distance of the superimposed constellation.Simulation results demonstrate the validness of our derivation.We also find that the proposed UDCGSVC has better BLER performance compared to other SVC schemes,especially under the high order modulation scenarios. 展开更多
关键词 ultra-reliable and low latency communications sparse vector coding uniquely decomposable constellation group constellation rotation short packet communications
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Molecular Dynamics Simulation of Hydrate Decomposition Under Action of Alcohol Inhibitors
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作者 Shuyan Wang Xuqing Zha +3 位作者 Baoli Shao Jing Wang Xi Chen Jiawei Fan 《Journal of Harbin Institute of Technology(New Series)》 CAS 2023年第6期12-28,共17页
The molecular dynamics method is used to investigate decomposition of methane hydrate at different temperatures,pressures and concentrations of inhibitor.By analyzing the parameters of system conformation,mean square ... The molecular dynamics method is used to investigate decomposition of methane hydrate at different temperatures,pressures and concentrations of inhibitor.By analyzing the parameters of system conformation,mean square displacement and radial distribution function,the decomposition of hydrate in the presence of alcohol inhibitors ethylene glycol and glycerol is explored.The results show that the hydroxyl groups in alcohol molecules can destroy the cage structure of hydrate,and form hydrogen bonds with nearby water molecules to effectively prevent the reformation of hydrate.Therefore,ethylene glycol and glycerol serve as inhibitors of methane hydrate,furthermore,in terms of inhibition effect,glycerol is better than ethylene glycol by comparing rate of hydrate decomposition. 展开更多
关键词 methane hydrate alcohol inhibitors molecular dynamics simulation decompose
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一种基于优化阈值函数的整体强化分解模型改进降噪方法 被引量:3
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作者 唐贵基 张文德 林琳 《科学技术与工程》 北大核心 2014年第16期134-138,共5页
以提高降噪效果为目的,提出了一种基于白噪声分解特性的EEMD优化阈值降噪方法。避免了小波分解时选择合适小波基函数的困难,具有自适应性,同时,也可以有效地避免频率混叠问题。方法从能量密度和对应平均周期乘积的变化率出发,提出了&qu... 以提高降噪效果为目的,提出了一种基于白噪声分解特性的EEMD优化阈值降噪方法。避免了小波分解时选择合适小波基函数的困难,具有自适应性,同时,也可以有效地避免频率混叠问题。方法从能量密度和对应平均周期乘积的变化率出发,提出了"跳变点"和"奇异点"的选择原则,并利用优化阈值函数对"跳变点"和"奇异点"对应的IMF分量进行量化处理,然后通过对处理后的IMF分量重构得到降噪信号。最后用仿真信号进行试验,证明本方法的有效性和优越性。 展开更多
关键词 整体强化分解模型(ensenble emprical MODE decompos sion EEMD) 优化阈值函数 降噪 跳变点 奇异点
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Screening of cellulose decomposing fungi in sandy dune soil of Horqin Sandy Land
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作者 ShaoKun Wang XueYong Zhao +4 位作者 XiaoAn Zuo XinPing Liu Hao Qu Wei Mao JianYing Yun 《Research in Cold and Arid Regions》 CSCD 2015年第1期74-80,共7页
Cellulose decomposing fungi play an important role in litter decomposition and are decisive in nutrient cycling in sandy land ecosystems. Thirty-one strains were isolated to select efficient cellulose decomposers, and... Cellulose decomposing fungi play an important role in litter decomposition and are decisive in nutrient cycling in sandy land ecosystems. Thirty-one strains were isolated to select efficient cellulose decomposers, and four efficient cellulose decomposing fungi (NM3-1, NM3-2, NM3-3, and NM3-4) were screened using a CMC (carboxymethyl cellulose) carbon source in dune soil of Horqin Sandy Land. They were identified as Asperigillus calidoustus, Fusarium oxysporum, Fusarium solani, and Hypocrea lixii by rDNA-ITS molecular biological methods. Cloth decomposition rates were 15.71%, 15.89%, 17.29%, and 17.89% by the four efficient decomposers incubated for 30 days, respectively. Screening of efficient cellulose decomposers can not only increase the dune soil functional microbe bank, but can also accelerate litter decom- position and available nutrient input in the Horqin Sandy Land. 展开更多
关键词 cellulose decomposer SCREENING sandy dune soil decomposition ability Horqin Sandy Land
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生物检材中氧乐果及其分解物的GC-MS分析 被引量:3
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作者 李绍鹏 苏少明 +2 位作者 韦忠 罗明胜 王瑞花 《分析测试学报》 CAS CSCD 北大核心 2007年第z1期281-282,284,共3页
A method was established for the analysis of omethoate and it’s concomitants and decomposed product in biological samples by GC-MS.This method is rapid,reliable and accurate.
关键词 OMETHOATE CONCOMITANTS Decomposed produce Biological samples GC-MS
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Allelopathy of decomposed maize straw products on three soilborn diseases of wheat and the analysis by GC-MS 被引量:22
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作者 QI Yong-zhi ZHEN Wen-chao LI Hai-yan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第1期88-97,共10页
In northern China, the soil-born diseases of wheat have been getting more and more serious under a new farming system that returns maize straw to the field. In order to investigate the allelopathy of the decomposed ma... In northern China, the soil-born diseases of wheat have been getting more and more serious under a new farming system that returns maize straw to the field. In order to investigate the allelopathy of the decomposed maize straw products on three soil-born diseases of wheat, culture dish and pot experiments were conducted and the compounds in the products were identified by gas chromatography-mass spectrometry (GC-MS). Culture dish experiments showed that the mycelial growth, sclerotia formation amount and total weight of Rhizoctonia cerealis were promoted at concentrations of 0.03, 0.06 and 0.12 g mL-1 and inhibited at concentration of 0.48 g mL-1 of the decomposed products. No significant effects were found of the product concentrations on average weight of the sclerotia. Mycelial growth of Gaeumannomyces graminis was promoted at almost all concentrations except the highest one. Mycelial growth and spore germination of Bipolaris sorokiniana were significantly inhibited by all concentrations of the decomposed products, with enhanced inhibition effects along with the increased concentrations. The length, number and dry weight of roots together with the root superoxide dismutase activity were promoted by the lowest concentration (0.03 g mL-1), with a synthetic effect index of 0.012, and inhibited by other concentrations. The ion leakage of roots was increased and the root peroxidase activity of roots was lowered by all the treatments. Pot experiments revealed that occurrence of the sharp eyespot was reduced by 0.03 and 0.06 g mL-1 of decomposed products after irrigation. However, the incidence rates and disease indexes were significantly increased by 0.12, 0.24 and 0.48 g mL-1 of decomposed products. The results indicated that incidence rates and disease indexes of the take-all were significantly promoted after being irrigated with the decomposed products, while occurrences of the common rot didn't change, significantly. GC-MS results showed that the compounds of the decomposed products included organic acids, esters, hydrocarbons, amides and aldehydes, with the proportions 25.26, 24.01, 17.22, 14.39 and 7.73%, respectively. Further analysis investigated that the allelochemicals identified in straw decomposed products contained p-hydroxybenzoic acid (9.21%), dibutyl phthalate (6.94%), 3-phenyl-2-acrylic (5.06%), 4-hydroxy-3,5-dimethoxybenzoic acid (2.26%), hexanoic acid (1.73%), 8-octadecenoic acid (1.06%), 3-(4-hydroxy-3-methoxy-phenyl)-2-propenoic acid (1.04%), 4-hydroxy-3-methoxy-benzoic acid (0.94%) and salicylic acid (0.94%). 展开更多
关键词 WHEAT soil-born disease maize straw decomposed products ALLELOPATHY GC-MS
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Screening on oil-decomposing microorganisms and application in organic waste treatment machine 被引量:9
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作者 LUYi-tong CHENXiao-bin ZHOUPei LIZhen-hong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第3期440-444,共5页
As an oil-decomposable mixture of two bacteria strains(Bacillus sp. and Pseudomonas sp.), Y3 was isolated after 50 d domestication under the condition that oil was used as the limited carbon source. The decomposing ra... As an oil-decomposable mixture of two bacteria strains(Bacillus sp. and Pseudomonas sp.), Y3 was isolated after 50 d domestication under the condition that oil was used as the limited carbon source. The decomposing rate by Y3 was higher than that by each separate individual strain, indicating a synergistic effect of the two bacteria. Under the conditions that T=25—40℃,pH=6—8, HRT(Hydraulic retention time)=36 h and the oil concentration at 0.1%, Y3 yielded the highest decomposing rate of 95.7 %. Y3 was also applied in an organic waste treatment machine and a certain rate of activated bacteria was put into the stuffing. A series of tests including humidity, pH, temperature, C/N rate and oil percentage of the stuffing were carried out to check the efficacy of oil-decomposition. Results showed that the oil content of the stuffing with inoculums was only half of that of the control. Furthermore, the bacteria were also beneficial to maintain the stability of the machine operating. Therefore, the bacteria mixture as well as the machines in this study could be very useful for waste treatment. 展开更多
关键词 oil-decomposing microorganism SCREENING application organic waste treatment machine decomposing rate
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Mobility Analysis of the Deployable Structure of SLE Based on Screw Theory 被引量:14
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作者 SUN Yuantao WANG Sanmin +1 位作者 LI Jianfeng ZHI Changjian 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第4期793-800,共8页
Scissor-like element has a number of applications in deployable structures such as planar deployable structure (PDS) and ring deployable structure(RDS). However, the mobility analysis of the multi-loop deployable stru... Scissor-like element has a number of applications in deployable structures such as planar deployable structure (PDS) and ring deployable structure(RDS). However, the mobility analysis of the multi-loop deployable structures is made more difficulty by the traditional mobility formula, because the deployable structure is a very complex structure with multi-loop. Therefore, On the basis of screw theory, the calculation method of mobility of deployable structures of SLE is thoroughly discussed. In order to investigate the mobility, decomposing and composing structures(DCS) are developed, and the basic units are able to be obtained. On the basis of the deployable structures’ geometrical characteristics, there exists a closed-loop quadrilateral structure and some non-closed-loop quadrilateral structures in PDS. Also, a six legs parallel structure is present in RDS. The basic units’ mobility can be solved by both the methods of screw theory and topology constraint graphs. Then, composing the related basic units, the formula of planar deployable structures’ mobility can be built and solves the mobility of ring deployable structure. The analysis method solves the mobility analysis of the multi-loop deployable structures which is difficulty by the traditional method, and plays an important role in further research about the mobility of other complex deployable structures. 展开更多
关键词 Scissor-like element(SLE) screw theory decomposing and composing structures (DCS) MOBILITY
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Effect of alginic acid decomposing bacterium on the growth of Laminaria japonica (Phaeophyceae) 被引量:8
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作者 WANG You TANG Xue-xi +1 位作者 YANG Zhen YU Zhi-ming 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第3期543-551,共9页
We collected the diseased blades of Larninaria japonica from Yantai Sea Farm from October to December 2002, and the alginic acid decomposing bacterium on the diseased blade was isolated and purified, and was identifie... We collected the diseased blades of Larninaria japonica from Yantai Sea Farm from October to December 2002, and the alginic acid decomposing bacterium on the diseased blade was isolated and purified, and was identified as A lteromonas espejiana. This bacterium was applied as the causative pathogen to infect the blades of L. japonica under laboratory conditions. The aim of the present study was to identify the effects of the bacterium on the growth of L. japonica, and to find the possibly effective mechanism. Results showed that: (1)The blades of L.japonica exhibited symptoms of lesion,bleaching and deteriortion when infected by the bacterium. and their growth and photosynthesis were dramatically suppressed. At the same time, the reactive oxygen species (ROS) generation enhanced obviously, and the relative membrane permeability increased significantly. The contents of malonaldehyde (MDA) and free fatty acid in the microsomol membrane greatly elevated, but the phospholipid content decreased. Result suggested an obvious peroxidation and deesterrification in the blades of L. japonica when infected by the bacterium. (2) The simultaneous assay on the antioxidant enzyme activities demonstrated that superoxide dismutase (SOD) and catalase (CAT) increased greatly when infected by the bacterium, but glutathione peroxidase (Gpx) and ascorbate peroxidase (APX) did not exhibit active responses to the bacterium throughout the experiment. (3) The histomorphological observations gave a distinctive evidence of the severity of the lesions as well as the relative abundance in the bacterial population on the blades after infection. The bacterium firstly invaded into the endodermis of L. japonica and gathered around there, and then resulted in the membrane damage, cells corruption and ultimately, the death of L. japonica. 展开更多
关键词 Laminaria japonica alginic acid decomposing bacterial INFECTION GROWTH MECHANISM
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Stimulatory effects of biosurfactant produced by Pseudomonas aeruginosa BSZ-07 on rice straw decomposing 被引量:7
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作者 Qiuzhuo ZHANG Juan WANG 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第8期975-980,共6页
Biosurfactant,produced by Pseudomonas aeruginosa BSZ-07,was added to the dee straw decomposing process to enhance the production of reducing sugars.Observed by Fourier Transform InfraRed(FT-IR)and Nuclear Magnetic Res... Biosurfactant,produced by Pseudomonas aeruginosa BSZ-07,was added to the dee straw decomposing process to enhance the production of reducing sugars.Observed by Fourier Transform InfraRed(FT-IR)and Nuclear Magnetic Resonance(NMR)analysis, the purified biosurfactant was considered as a mixture of RL1 and RL2,which are two different types of rhamnolipids.Two different adding methods,adding the purified rhamnolipid and the on-site production of it were compared.The results showed that 0.5 g/L was the optimum co... 展开更多
关键词 BIOSURFACTANT RHAMNOLIPID ON-SITE rice straw decomposing
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Effects of Citric Acid on Hydration Process and Mechanical Properties of Thermal Decomposed Magnesium Oxychloride Cement 被引量:8
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作者 文静 余红发 +2 位作者 LI Ying WU Chengyou DONG Jinmei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第1期114-118,共5页
In order to make full use of salt lake magnesium resources and improve the strength of the thermal decomposed magnesium oxychloride cement (TDMOC), the effects of citric acid on the hydration process and mechanical ... In order to make full use of salt lake magnesium resources and improve the strength of the thermal decomposed magnesium oxychloride cement (TDMOC), the effects of citric acid on the hydration process and mechanical properties of TDMOC was studied. The hydration heat release at initial 24 h and strengths at 3, 7, and 28 days of TDMOC specimens were conducted. The hydration products and paste microstructure were analyzed by XRD, FT-IR and SEM, respectively. The results showed that citric acid can not only reduce the 24 h hydration heat release and delay the occurring time of second peak of TDMOC, but also produce more 5Mg(OH)z.MgC12.SH20 and less Mg(OH)2 in hydration process of TDMOC. More perfect and slender crystals were observed in the microstructure of the TDMOC pastes with citric acid. The results demonstrated that citric acid as an additive of TDMOC can decrease the hydration heat release and increase the compressive strength and flexural strength of TDMOC. The possible mechanism for the strength enhancement was discussed. 展开更多
关键词 thermal decomposed magnesium oxychloride cement citric acid hydration heat STRENGTH
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DYNAMICS OF LITTER DECOMPOSITION AND SEASONAL DYNAMICS OF PHOSPHORUS IN DECOMPOSED RESIDUA OF Calamagrotis augustifolia IN THE WETLAND OF THE SANJIANG PLAIN 被引量:3
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作者 Shi-yan Wang Yong-xing Yang 《Chinese Geographical Science》 SCIE CSCD 2001年第3期73-78,共6页
During the period of May to October in1999,systematical studies were giv en to the rate of decomposition of Calamagrostis angustifolia litter,the phosphorus content and weight in decomposed residua of litte r,and phos... During the period of May to October in1999,systematical studies were giv en to the rate of decomposition of Calamagrostis angustifolia litter,the phosphorus content and weight in decomposed residua of litte r,and phosphorus content in the corresponding soil in the Sanjiang Plain.At the same time,the simulation models were listed in the paper.The results showed that the rate of we ight lost of decomposition of Calamagrostis angustifolia litter is 29.80%and the maximum of daily rate of weight lost i s 0.25%,which appeared in July.The c hange trend of phosphorus content an d weight in the decomposed residua of l itter is to reduce with the decomposing process,when it comes to the day of157,the decrement amount of the both were respectively 57.69mg /kg and 1.6199mg,which were 72.80%and 76.30%of its previous amount.In addition,th ere is a polynomial minus correlatio nship of phosphorus content between the variation in corresponding soil and the decomp osed residua of litter at the corresp onding period.The study will be help ful to further understand the process and mechanis m of biochemical cycling of nutrient elements in wetland ecosystems,in a ddition,it will also be helpful to the restoration and rebuilding of retrogressive wetlands and reasonable development and utilization of wetlands in the Sanjiang Plain. 展开更多
关键词 Calamagrostis angustifolia LITTER decomposed residua phosph orus SEASONAL DYNAMICS Sanjiang PLAIN
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Fabric Defect Detection Using Adaptive Wavelet Transform 被引量:4
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作者 李立轻 黄秀宝 《Journal of Donghua University(English Edition)》 EI CAS 2002年第1期35-39,共5页
A method of woven fabric defect detection using the wavelet transform adaptive to the fabric has been developed. With reference to the orthogonality constrains of Daubechies wavelet, by taking the mmimization of the e... A method of woven fabric defect detection using the wavelet transform adaptive to the fabric has been developed. With reference to the orthogonality constrains of Daubechies wavelet, by taking the mmimization of the energy or the gray level of the pixels in the output sub-images as the additional conditions and using the random algorithm method, two sets of wavelet filters adapted to the fabric texture were formed. The original images of normal fabric texture and the fabric texture with defects were decomposed into horizontal and vertical sub- images by using these filters and the feature indices of these sub-images were also extracted. By comparing the feature indices of the normal texture with that of the defective texture, the fabric defects can be successfully detected and located. 展开更多
关键词 WAVELET transform ADAPTIVE wavelet IMAGE decompose FABRIC DEFECT detection.
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Unrevealing the effects of low temperature on cycling life of 21700-type cylindrical Li-ion batteries 被引量:3
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作者 Daozhong Hu Gang Chen +8 位作者 Jun Tian Ning Li Lai Chen Yuefeng Su Tinglu Song Yun Lu Duanyun Cao Shi Chen Feng Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第9期104-110,共7页
The low-temperature performance of Li-ion batteries(LIBs) has important impacts on their commercial applications. Besides the metallic lithium deposition, which is regarded as one of the main failure mechanisms of the... The low-temperature performance of Li-ion batteries(LIBs) has important impacts on their commercial applications. Besides the metallic lithium deposition, which is regarded as one of the main failure mechanisms of the LIBs at low temperatures, the synergistic effects originating from the cathode, anode, electrolyte, and separators to the batteries are still not clear. Here, the 21700-type cylindrical batteries were evaluated at a wide range of temperatures to investigate the failure mechanism of batteries. Voltage relaxation, and the post-mortem analysis combined with the electrochemical tests, unravel that the capacity degradation of batteries at low temperature is related to the lithium plating at graphite anodes,the formation of unsatisfied solid deposited/decomposed electrolyte mixture phase on the anode, the precipitation of solvent in the electrolytes and the block of separator pores, and the uneven dissolved transition metal-ions from the cathode. We hope this finding may open up a new avenue to alleviate the capacity degradation of advanced LIBs at low temperatures and shed light on the development of outstanding low-temperature LIBs via simultaneous optimization of all the components including electrodes, electrolytes and separators. 展开更多
关键词 Low temperature Cycling life Lithium plating Solid deposited/decomposed electrolyte mixture phase Voltage relaxation
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CONTINUOUS SELECTIONS OF SOLUTION SETS OF FRACTIONAL INTEGRO-DIFFERENTIAL INCLUSIONS 被引量:3
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作者 Aurelian CERNEA 《Acta Mathematica Scientia》 SCIE CSCD 2015年第2期399-406,共8页
Using Bressan-Colombo results, concerning the existence of continuous selections of lower semicontinuous multifunctions with decomposable values, we prove a continuous version of Filippov's theorem for a fractional i... Using Bressan-Colombo results, concerning the existence of continuous selections of lower semicontinuous multifunctions with decomposable values, we prove a continuous version of Filippov's theorem for a fractional integro-differential inclusion involving Caputo's fractional derivative. This result allows us to obtain a continuous selection of the solution set of the problem considered. 展开更多
关键词 Differential inclusion fractional derivative decomposable set
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An Approach for Improving Short-Term Prediction of Summer Rainfall over North China by Decomposing Interannual and Decadal Variability 被引量:2
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作者 HAN Leqiong LI Shuanglin LIU Na 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第2期435-448,共14页
A statistical downscaling approach was developed to improve seasonal-to-interannual prediction of summer rainfall over North China by considering the effect of decadal variability based on observational datasets and d... A statistical downscaling approach was developed to improve seasonal-to-interannual prediction of summer rainfall over North China by considering the effect of decadal variability based on observational datasets and dynamical model outputs.Both predictands and predictors were first decomposed into interannual and decadal components.Two predictive equations were then built separately for the two distinct timescales by using multivariate linear regressions based on independent sample validation.For the interannual timescale,850-hPa meridional wind and 500-hPa geopotential heights from multiple dynamical models' hindcasts and SSTs from observational datasets were used to construct predictors.For the decadal timescale,two well-known basin-scale SST decadal oscillation (the Atlantic Multidecadal Oscillation and the Pacific Decadal Oscillation) indices were used as predictors.Then,the downscaled predictands were combined to represent the predicted/hindcasted total rainfall.The prediction was compared with the models' raw hindcasts and those from a similar approach but without timescale decomposition.In comparison to hindcasts from individual models or their multi-model ensemble mean,the skill of the present scheme was found to be significantly higher,with anomaly correlation coefficients increasing from nearly neutral to over 0.4 and with RMSE decreasing by up to 0.6 mm d-1.The improvements were also seen in the station-based temporal correlation of the predictions with observed rainfall,with the coefficients ranging from-0.1 to 0.87,obviously higher than the models' raw hindcasted rainfall results.Thus,the present approach exhibits a great advantage and may be appropriate for use in operational predictions. 展开更多
关键词 summer rainfall short-term prediction decomposing DOWNSCALING
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Precise integration methods based on the Chebyshev polynomial of the first kind 被引量:2
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作者 Wang Mengfu F. T. K. Au 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2008年第2期207-216,共10页
This paper introduces two new types of precise integration methods based on Chebyshev polynomial of the first kind for dynamic response analysis of structures, namely the integral formula method (IFM) and the homoge... This paper introduces two new types of precise integration methods based on Chebyshev polynomial of the first kind for dynamic response analysis of structures, namely the integral formula method (IFM) and the homogenized initial system method (HISM). In both methods, nonlinear variable loadings within time intervals are simulated using Chebyshev polynomials of the first kind before a direct integration is performed. Developed on the basis of the integral formula, the recurrence relationship of the integral computation suggested in this paper is combined with the Crout decomposed method to solve linear algebraic equations. In this way, the IFM based on Chebyshev polynomial of the first kind is constructed. Transforming the non-homogenous initial system to the homogeneous dynamic system, and developing a special scheme without dimensional expansion, the HISM based on Chebyshev polynomial of the first kind is able to avoid the matrix inversion operation. The accuracy of the time integration schemes is examined and compared with other commonly used schemes, and it is shown that a greater accuracy as well as less time consuming can be achieved. Two numerical examples are presented to demonstrate the applicability of these new methods. 展开更多
关键词 structural dynamics Chebyshev polynomial of the first kind the Crout decomposed method integral formula method homogenized initial system method
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A Timescale Decomposed Threshold Regression Downscaling Approach to Forecasting South China Early Summer Rainfall 被引量:2
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作者 Linye SONG Wansuo DUAN +1 位作者 Yun LI Jiangyu MAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第9期1071-1084,共14页
A timescale decomposed threshold regression (TSDTR) downscaling approach to forecasting South China early summer rainfall (SCESR) is described by using long-term observed station rainfall data and NOAA ERSST data.... A timescale decomposed threshold regression (TSDTR) downscaling approach to forecasting South China early summer rainfall (SCESR) is described by using long-term observed station rainfall data and NOAA ERSST data. It makes use of two distinct regression downscaling models corresponding to the interannual and interdecadal rainfall variability of SCESR. The two models are developed based on the partial least squares (PLS) regression technique, linking SCESR to SST modes in preceding months on both interannual and interdecadal timescales. Specifically, using the datasets in the calibration period 1915-84, the variability of SCESR and SST are decomposed into interannual and interdecadal components. On the interannual timescale, a threshold PLS regression model is fitted to interannual components of SCESR and March SST patterns by taking account of the modulation of negative and positive phases of the Pacific Decadal Oscillation (PDO). On the interdecadal timescale, a standard PLS regression model is fitted to the relationship between SCESR and preceding November SST patterns. The total rainfall prediction is obtained by the sum of the outputs from both the interannual and interdecadal models. Results show that the TSDTR downscaling approach achieves reasonable skill in predicting the observed rainfall in the validation period 1985-2006, compared to other simpler approaches. This study suggests that the TSDTR approach, considering different interannual SCESR-SST relationships under the modulation of PDO phases, as well as the interdecadal variability of SCESR associated with SST patterns, may provide a new perspective to improve climate predictions. 展开更多
关键词 timescale decomposed threshold regression South China early summer rainfall forecasting skill
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EMPIRICAL ORTHOGONAL MODES IN THE WESTERN PACIFIC 被引量:1
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作者 崔茂常 胡敦欣 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1990年第4期328-335,共8页
The method of empirical orthogonal modes has been widely used since the 1970’s in physical oceanography to study and rebuild vertical structures of ocean dynamic factors. Because of the dominance of the low modes, th... The method of empirical orthogonal modes has been widely used since the 1970’s in physical oceanography to study and rebuild vertical structures of ocean dynamic factors. Because of the dominance of the low modes, the dynamic profile data can be largely reduced.Up to now, all expressions of empirical orthogonal modes are numerical. In this study, an analytic expression for empirical orthogonal ocean modes is constructed for convenient use whereby any numerical expressions can be repeated.The features of the normal modes decomposed from the buoyance frequency profiles obtained in October of 1986,1987 and 1988 by the R/V Science 1 in the western Pacific are quantitatively examined in this study. 展开更多
关键词 decomposed empirical OCEAN CONVENIENT DOMINANCE quantitatively largely normalized instead ANALYTIC
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An initial study of insect succession on decomposing rabbit carrions in Harare,Zimbabwe 被引量:1
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作者 Nyasha Mabika Ron Masendu Gilbert Mawera 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2014年第7期561-565,共5页
Objective:To investigate insects visiting sun exposed and shaded decomposing rabbit carcasses and to establish the relationship between insects and carcasses which may be of forensic importance in Harare.Methods:Two r... Objective:To investigate insects visiting sun exposed and shaded decomposing rabbit carcasses and to establish the relationship between insects and carcasses which may be of forensic importance in Harare.Methods:Two rabbits weighing 2.3 kg and 2.5 kg were killed by sharp blows on the head.One was exposed to the sun while the other was placed under shade.The carcasses were allowed to decompose and insects were collected twice a day for the first week and thereafter once a day up to the end of the 7 weeks.Maggots were also collected from the decomposing carcasses and reared.Results:Five dipteran families(Galliphoridae,Muscidae,Sarcophagidae,Phoridae and Drosophilidae)were identified from the sun-exposed carcass.Species collected included Lucilia cuprina(L.cuprina),Chrysomya albiceps(C.albiceps),Musca domestica,Sarcophaga sp.and Drosophila sp.Four families(Calliphoridae,Muscidae,Phoridae,Anthomyiidae)were identified from the shaded carcass.Representatives of these families included L cuprina,C.albiceps,Musca domestica,and Hydrotaea sp.Three Coleopteran families(Histeridae,Cleridae and Dermestidae)were identified from hodt carcasses.The observed species were Saprinus sp,Necrobia rufipes and Dermestes sp.Fomicidae(Hymenoptera)was represented by only one species(Pheidoie sp.)Flies which emerged from the rearing units were L cuprina,Lucilia sp.,C.albiceps,Sarcophaga sp.and Sepsis sp.).Conclusions:Of the dipteran species collected during the study,L cuprina and C.albiceps could be important for further forensic studies since they were collected from the carcasses and also observed from the rearing units. 展开更多
关键词 INSECT SUCCESSION Forensic ENTOMOLOGY Decomposing RABBIT CARRION
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