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煤焦O_2/CO_2燃烧反应性及结构演化的分子模拟研究 被引量:1
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作者 王长安 辛海会 +2 位作者 Justin K.Watson 车得福 Jonathan P.Mathews 《工程热物理学报》 EI CAS CSCD 北大核心 2016年第7期1583-1588,共6页
本文通过自编程序Fringe3D和Vol3D构建了具备一定孔隙结构特征的大尺度煤焦分子模型(碳原子数40000),通过简化的分子模拟方法编程实现了煤焦O2/CO2燃烧微观反应过程的模拟。模拟结果表明:随着燃烧反应的进行,煤焦结构逐渐"缩核"变... 本文通过自编程序Fringe3D和Vol3D构建了具备一定孔隙结构特征的大尺度煤焦分子模型(碳原子数40000),通过简化的分子模拟方法编程实现了煤焦O2/CO2燃烧微观反应过程的模拟。模拟结果表明:随着燃烧反应的进行,煤焦结构逐渐"缩核"变小,而煤焦结构尺寸的变化主要发生在燃烧后期。随着碳转化率的增大,低活性碳原子的数量逐渐减少,而高活性碳原子的数量先增加后减少。与空气燃烧相比,煤焦在O2/CO2气氛下的燃烧过程明显延迟,而煤焦比表面积的改变对煤焦反应性的变化有紧密关联。 展开更多
关键词 煤焦 大尺度分子模型 O2/CO2燃烧 简化的分子模拟
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Tong xie yao fang relieves irritable bowel syndrome in rats via mechanisms involving regulation of 5-hydroxytryptamine and substance P 被引量:30
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作者 Yue Yin Lei Zhong +3 位作者 Jian-Wei Wang Xue-Ying Zhao Wen-Jing Zhao Hai-Xue Kuang 《World Journal of Gastroenterology》 SCIE CAS 2015年第15期4536-4546,共11页
AIM: To investigate whether the Chinese medicine Tong Xie Yao Fang(TXYF) improves dysfunction in an irritable bowel syndrome(IBS) rat model. METHODS: Thirty baby rats for IBS modeling were separated from mother rats(1... AIM: To investigate whether the Chinese medicine Tong Xie Yao Fang(TXYF) improves dysfunction in an irritable bowel syndrome(IBS) rat model. METHODS: Thirty baby rats for IBS modeling were separated from mother rats(1 h per day) from days 8 to 21, and the rectum was expanded by angioplasty from days 8 to 12. Ten normal rats were used as normal controls. We examined the effects of TXYF on defection frequency, colonic transit function and smooth muscle contraction, and the expression of 5-hydroxytryptamine(5-HT) and substance P(SP) in colonic and hypothalamus tissues by Western blot and RT-PCT techniques in both normal rats and IBS model rats with characterized visceral hypersensitivity.in normal rats and 4.5 ± 1.58 in IBS model rats(P < 0.001). However, the defecation frequency was significantly decreased(3.0 ± 1.25 vs 4.5 ± 1.58, P < 0.05), while the time(in seconds) of colon transit function was significantly increased(256.88 ± 20.32 vs 93.36 ± 17.28, P < 0.001) in IBS + TXYF group rats than in IBS group rats. Increased colonic smooth muscle tension and contract frequency in IBS model rats were significantly decreased by administration of TXYF. Exogenous agonist stimulants increased spontaneous activity and elicited contractions of colon smooth muscle in IBS model rats, and all of these actions were significantly reduced by TXYF involving 5-HT and SP down-regulation. CONCLUSION: TXYF can modulate the activity of the enteric nervous system and alter 5-HT and SP activities, which may contribute to the symptoms of IBS. 展开更多
关键词 Tong Xie YAO Fang IRRITABLE BOWEL SYNDROME 5-HYDROXYTRYPTAMINE Substance P TRADITIONAL Chinesemedicine
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Epidemiology of cercarial stage of trematodes in freshwater snails from Chiang Mai province,Thailand 被引量:5
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作者 Thapana Chontananarth Chalobol Wongsawad 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第3期237-243,共7页
Objective:To investigate the epidemiological situation of cercarial trematodes infection in freshwater snails from different water resources in Chiang Mai province,Thailand.Methods:The snail specimens were collected f... Objective:To investigate the epidemiological situation of cercarial trematodes infection in freshwater snails from different water resources in Chiang Mai province,Thailand.Methods:The snail specimens were collected from 13 districts of Chiang Mai province during April 2008 to February 2012.The prevalence of cercarial infection in snails was investigated using the crushing method.The drawing was done with the help of a camera lucida for the morphological study.Results:A total of 2479 snail individuals were collected and classified into 7 families,11 genera,and 14 species,Among them,8 snails species were found to be infected with an overall prevalence of 17.27%(428/2479),which infected with nine groups of cercariae;gymnocephalous cercaria,strigea cercaria,megalurous cercaria,monostome cercaria,parapleurolophocercous cercaria(Haplorchis cercaria),pleurolophocercous cercaria,furcocercous cercaria(Transversotrema cercaria),xiphidiocercaria,and virgulate cercaria.The parapleurolophocercous cercaria was found to be the dominant type among the cercarial infection in the snails(64.25%).Conclusions:The various species of snails found in the research location act as the intermediate hosts for the high prevalence of parasitic infection of many species of mammals.This work will provide new information on both the distribution and first intermediate host of trematodes. 展开更多
关键词 Chiang MAI TREMATODES CERCARIAE Pleurolophocercous PREVALENCE FRESHWATER SNAILS
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Designing multilayer diamond like carbon coatings for improved mechanical properties 被引量:6
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作者 Mohammad Sharear Kabir Zhifeng Zhou +1 位作者 Zonghan Xie Paul Munroe 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2021年第6期108-117,共10页
New multilayer coatings were produced by incorporating alternating soft and hard DLC layers enabled by varying the bias voltage during deposition process while maintaining a constant hard-to-soft layer thickness ratio... New multilayer coatings were produced by incorporating alternating soft and hard DLC layers enabled by varying the bias voltage during deposition process while maintaining a constant hard-to-soft layer thickness ratio.These coatings were deposited onto a Cr/Cr Cxgraded layer by closed field unbalanced magnetron sputtering(CFUBMS).The cross-sectional analysis of the coatings showed that the multilayer coatings possess sharp interfaces between the soft and hard layers with the hard to soft layer thickness ratio(1:1.33)constant in all the coatings.Raman analysis uncovered the increasing sp^(3)character of the DLC coatings as a result of decreasing ID/IGratio and increasing full width at half maximum(FWHM)values of the G band peak induced supposedly by an increase in bias voltage during hard layer deposition.Nanoindentation tests showed an increase in hardness of the DLC coatings which can be correlated with the increase in the sp^(3)content of the coatings as well as decreasing sp^(2)-C cluster size,as calculated from the ID/IGratio.Furthermore,the coatings exhibited excellent plastic deformation resistance and adhesion strength upon microindentation and scratch testing,respectively.Although further investigations are required to assess coating durability,the multilayer design could offer the DLC coatings with a rare opportunity to combine the high hardness with damage resistance with a constant bilayer thickness and without the need to introduce complex multilayer system. 展开更多
关键词 Diamond like carbon(DLC) Closed field unbalanced magnetron sputtering(CFUBMS) sp^(3)Character NANOINDENTATION Plastic deformation resistance Scratch adhesion behaviour
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Mechanical Behaviors of Ti-Si-N Coatings Deposited by Bias Sputtering 被引量:2
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作者 P W Shum 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2012年第S1期18-23,共6页
Ti-Si-N hard coatings were deposited on steel substrates by reactive unbalanced magnetron sputtering from Ti and Si elemental targets in a mixture of Ar and N2 gases.The influences of negative bias voltage(in the rang... Ti-Si-N hard coatings were deposited on steel substrates by reactive unbalanced magnetron sputtering from Ti and Si elemental targets in a mixture of Ar and N2 gases.The influences of negative bias voltage(in the range of-30 to-80 V)on the mechanical properties of the coatings were investigated.In particular,the critical cycle during dynamic impact tests was employed to indicate the bonding strength of the coatings.It was found that the Ti-Si-N coatings prepared at lower constant bias voltages could effectively improve the adhesion and the cyclic impact performance,but their hardness was dropped significantly to 13 GPa at a bias of-30 V.Higher bias voltage values induced greater hardness.A maximum hardness of 47 GPa was obtained at a bias of-60 V.However,the coating adhesion was worse in this case,and the number of impact cycles(~8×10 3)that the coatings could endure was much shorter than that of TiN binary coatings(~2×104).On the other hand,the bias voltage was varied linearly from-40 to-60 V during Ti-Si-N deposition.Under this circumstance,the hardness of the coatings deposited with the bias-graded configuration remained very high(42 GPa),and the adhesion strength was improved substantially.Also,the critical impact cycle could reach as high as 1.8×104.Therefore,bias-graded deposition can provide an effective processing route to prepare Ti-Si-N superhard coatings with high adhesion strength and impact resistance. 展开更多
关键词 TI-SI-N COATINGS MAGNETRON SPUTTERING BIAS voltage mechanical properties impact test
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Restoration of an Inner-City Stream and Its Impact on Air Temperature and Humidity Based on Long-Term Monitoring Data 被引量:2
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作者 Kyu Rang KIM Tae Heon KWON +3 位作者 Yeon-Hee KIM Hae-Jung KOO Byoung-Cheol CHOI Chee-Young CHOI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第2期283-292,共10页
Spatiotemporal changes in air temperature and humidity associated with the restoration of an innercity stream in Seoul, Korea, are investigated based on long-term monitoring data. The Cheonggye stream, covered under a... Spatiotemporal changes in air temperature and humidity associated with the restoration of an innercity stream in Seoul, Korea, are investigated based on long-term monitoring data. The Cheonggye stream, covered under a concrete structure for 46 years, was restored in 2005 and runs 5.8 km eastward through a central region of Seoul. Long-term monitoring of the air temperature and relative humidity was made along the stream throughout the restoration and across the stream after the restoration. The area along the stream had a higher air temperature than the entire metropolitan area. The temperature anomaly between the monitoring area and the surrounding metropolitan area was 0.13℃ lower on average at the center of the stream after the restoration. The stream's effect on the air temperature was also evident in the temperature distribution along a street traversing the stream. The relative and specific humidities were increased due to the restoration. The restored stream modified the nearby urban climate in the opposite direction compared to urbanization. The results could be used as a model case in mitigating urban climate by a stream in future urban planning practices. 展开更多
关键词 urban heat island STREAM RESTORATION land-use VEGETATION Cheonggye stream
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Tailoring surface roughness of LaMnO_(3) buffer layers for YBCO-coated conductors 被引量:2
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作者 Chao Yang Yuan-Ying He +5 位作者 Jun-Wei Chu Yan Xue Fei Zhang Wang Hui Bo-Wan Tao Jie Xiong 《Rare Metals》 SCIE EI CAS CSCD 2015年第12期859-863,共5页
LaMnO_(3)(LMO) cap layers with different surface roughness were prepared on epi-MgO/ion-beam-assisted deposition (IBAD) MgO/solution deposition planarized (SDP) Y<sub>2</sub>O<sub>3</sub>/Haste... LaMnO_(3)(LMO) cap layers with different surface roughness were prepared on epi-MgO/ion-beam-assisted deposition (IBAD) MgO/solution deposition planarized (SDP) Y<sub>2</sub>O<sub>3</sub>/Hastelloy tape. The effects of the surface roughness of LMO on the crystallization, texture and superconducting properties of Yba<sub>2</sub>Cu<sub>3</sub>O<sub>7?δ </sub> (YBCO) films were systematically investigated. The crystallization and epitaxial texture of resulting YBCO film are significantly improved with the surface roughness of LMO decreasing from 7.0 to 1.3nm. High-performance YBCO-coated conductors could be achieved if surface roughness of LMO cap layer is well controlled. 展开更多
关键词 YBa_(2)Cu_(3)O_(7-δ)(YBCO) Coated conductors LaMnO_(3)cap Surface ROUGHNESS SUPERCONDUCTING properties
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Epidemiological situation and molecular identification of cercarial stage in freshwater snails in Chao-Phraya Basin, Central Thailand 被引量:1
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作者 Sothorn Anucherngchai Thanawan Tejangkura Thapana Chontananarth 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2016年第6期539-545,共7页
Objective: To investigate the prevalence of cercarial trematode infection in snails and to examine the reconstruction of the phylogenetic relationship to explain the molecular system of cercarial stage trematodes to e... Objective: To investigate the prevalence of cercarial trematode infection in snails and to examine the reconstruction of the phylogenetic relationship to explain the molecular system of cercarial stage trematodes to estimate the infection rate of in the definite host from the Chao-Phraya Basin.Methods: The snails were collected from 10 provinces of the Chao-Phraya Basin,Thailand by stratified sampling method. The snails were examined for cercarial infection by the crushing method. All DNA specimens were amplified with internal transcribed spacer 3(ITS3) and ITS4 primer based on PCR technique. The sequence data were aligned and used to reconstruct the phylogenetic tree by unweighted pair-group method with arithmetic means with 10 000 bootstraps.Results: The overall rate of cercarial infection was found to be 5.90%(122/2 067). Snails in the family Thiaridae were found to be in the highest prevalence followed by Lymnaeidae, Bithyniidae, Planorbidae, Viviparidae, and Ampullariidae, respectively, while the Buccinidae family(Clea helena) did not reveal any infections. The frequently found species of cercariae were parapleurolophocercous cercariae, cercariae and megarulous cercariae. The monophyletic tree separated the snails into five groups comprised of Heterophyidae, Strigeidae, Lecithodendriidae, Philophthalmidae and Echinostomatidae using the sequence of Angiostrongylus cantonensis as an out-group.Conclusions: This study was the first to report on cercarial infection in the Chao-Phraya Basin, Thailand. This revealed that a high variety of freshwater snails were infected by cercariae stage trematodes with a high prevalence. The sequence data of ITS2 can be used to investigate the phylogenetic relationships of trematodes at the family level and in each clade of different families separated by the definitive hosts. 展开更多
关键词 PREVALENCE Molecular identification Cercarial INFECTION FRESHWATER SNAILS Thailand
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TRIBOLOGICAL AND HIGH SPEED TURNING PERFORMANCE IN Ti_(1-x)Al_(x)N COATINGS PREPARED BY CLOSE-FIELD UNBALANCED MAGNETRON SPUTTERING 被引量:1
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作者 P.W.Shum M.Escursell +3 位作者 T.H.Wong K.Y.Li Z.F.Zhou Y.G.Shen 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2005年第3期254-260,共7页
Titanium-aluminium-nitride(Ti_(1-x)Al_(x)N)coatings were deposited by close-field un balanced magnetron sputtering on M42 steel substrates and WC-6wt%Co inserts at 450℃.The tribological behavior was analyzed by slidi... Titanium-aluminium-nitride(Ti_(1-x)Al_(x)N)coatings were deposited by close-field un balanced magnetron sputtering on M42 steel substrates and WC-6wt%Co inserts at 450℃.The tribological behavior was analyzed by sliding against steel and WC-6wt%Co balls,while the turning performance was evaluated by a conventional tu rning machine at high cutting speeds without using coolants.In the tribological tests,the formation of transfer layer and the variations of hardness of the co atings played an important role for sliding against steel balls.For the coating s sliding against WC-6wt%Co balls,the Ti-Al-N coatings showed a similar frictio n coefficient,but the TiN coating exhibited a lower value.The difference could be explained by the tri-oxidation wear mechanism.In the turning tests,a super ior cutting performance of the coating was found at x=0.45,which endured 38 min utes before the tool flank wear reached the maximum value of 0.3mm,whereas only 20 minutes were endured for the TiN coating.The excellent performance of the c oatings in the turning tests could be explained by the enhanced mechanical prope rties and oxidation/diffusion resistance of the coatings. 展开更多
关键词 hardness Ti-Al-N coating TRIBOLOGY turning test wear test
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A fault-tolerant triple-redundant voice coil motor for direct drive valves:Design, optimization, and experiment 被引量:4
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作者 Wu Shuai Jiao Zongxia +2 位作者 Yan Liang Yu Juntao Chen Chin-Yin 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第4期1071-1079,共9页
A direct drive actuator (DDA) with direct drive valves (DDVs) as the control device is an ideal solution for a flight actuation system. This paper presents a novel triple-redundant voice coil motor (TRVCM) used ... A direct drive actuator (DDA) with direct drive valves (DDVs) as the control device is an ideal solution for a flight actuation system. This paper presents a novel triple-redundant voice coil motor (TRVCM) used for redundant DDVs. The TRVCM features electrical/mechanical hybrid triple-redundancy by securing three stators along with three moving coils in the same frame. A permanent magnet (PM) Halbach array is employed in each redundant VCM to simplify the system structure. A back-to-back design between neighborly redundancies is adopted to decouple the magnetic flux linkage. The particle swarm optimization (PSO) method is implemented to optimize design parameters based on the analytical magnetic circuit model. The optimization objective function is defined as the acceleration capacity of the motor to achieve high dynamic performance. The optimal geometric parameters are verified with 3D magnetic field finite element analysis (FEA). A research prototype has been developed for experimental purpose. The experimental results of magnetic field density and force output show that the proposed TRVCM has great potential of applications in DDA systems. 展开更多
关键词 Direct drive valve Hydraulic flight control Magnetic field optimization Particle swarm optimization Redundant motor
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Epidemiology and molecular genotyping of echinostome metacercariae in Filopaludina snails in Lamphun Province,Thailand 被引量:1
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作者 Waraporn Noikong Chalobol Wongsawad 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2014年第1期26-29,共4页
Objective:To analyze the prevalence of echinostome metacercariae in Filopaludina dorliaris(F.dorliaris)and Filopaludina martensi martensi(F.martensi martensi)and genotype variation of echinostome metacercariae by usin... Objective:To analyze the prevalence of echinostome metacercariae in Filopaludina dorliaris(F.dorliaris)and Filopaludina martensi martensi(F.martensi martensi)and genotype variation of echinostome metacercariae by using random amplified polymorphic DNA(RAPD)analysis.Methods:Filopaludina sp.snails were collected from eight localities of Lamphun Province,Northern Thailand and examined for echinostome metacercariae.RAPD-PCR was used lo analyze genotype variation of echinostome metacercariae.Results:A total of 3 226 F.dorliaris and F.martensi martensi snails were collected from eight localities.The overall prevalences of echinostome metacercariae in F.dorliaris and F.martensi martensi were 40.89%and 36.27%,while the intensity of infection was 20.37 and 12.04,respectively.The dendrogram constructed base on RAPD profiles,4 well supported domains were generated;(i)group of metacercariae from Ban Hong,Mae Ta,Meaung,Pa Sang,Toong Hua Chang,and Weang Nong that were clustered in the group of E.revolutum,(ii)Ban Thi,(iii)Lee,and(iv)3 adults of an out group.Condusioiis:This research demonstrated RAPD profiling has been a useful tool to detect DNA polymorphisms to determine genetic relationship between echinostome metacercariae in Lamphun Province,Northern Thailand. 展开更多
关键词 ECHINOSTOMA sp. Filopaludina sp.snails RAPD-PCR EPIDEMIOLOGY METACERCARIAE
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Molecular phylogeny of trematodes in Family Heterophyidae based on mitochondrial cytochrome c oxidase subunit Ⅰ(mCO Ⅰ) 被引量:1
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作者 Thapana Chontananarth Chalobol Wongsawad +2 位作者 Siriwadee Chomdej Duangduen Krailas Jong Yil Chai 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2014年第6期446-450,共5页
Objective:To analyze a phylogenetic tree for understanding the molecular systematic of trematode in Pamily Heterophyidae.which are highly distributed in Thailand.Methods:Based on thirteen sequences of mitochondrial cy... Objective:To analyze a phylogenetic tree for understanding the molecular systematic of trematode in Pamily Heterophyidae.which are highly distributed in Thailand.Methods:Based on thirteen sequences of mitochondrial cytochrome C oxidase subunit 1(mCO I) gene from six genera of heterophyid trernatodes,riz.Haplorchis,Stellantchasmus,Centrocestus,Metagonimus,Pygidopsis,and Haplnrchoides were aligned automatically using the Clustal × 2.0 program.A phylogenetic tree was constructed by maximum likeiughood(ML) and neighbor-joining(NJ)methods,with 1000 bootstrap using the 5.0 program.Results:The phylogenetic relationship from both methods was similar and separated into three groups consisting of Haplorchoides pumilio group,Haplorchoides taichui group and another heterophyid genera.Comclusions:The sequence data of mtCOl can he used to investigate the phylogenetic relationships of trernatodes at the genus level.Each clade of different genera of heterophyid trernatodes can be separated into sister groups that correlated with the morphological characteristic,kind of secondary intermediate host and geographic distribution. 展开更多
关键词 PHYLOGENETIC RELATIONSHIP mCOI Heterophyidae
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An Overset Grid Method for Fluid-Structure Interaction 被引量:1
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作者 Scott T. Miller R. L. Campbell +2 位作者 C. W. Elsworth J. S. Pitt D. A. Boger 《World Journal of Mechanics》 2014年第7期217-237,共21页
An overset grid methodology is developed for the fully coupled analysis of fluid-structure interaction (FSI) problems. The overset grid approach alleviates some of the computational geometry difficulties traditionally... An overset grid methodology is developed for the fully coupled analysis of fluid-structure interaction (FSI) problems. The overset grid approach alleviates some of the computational geometry difficulties traditionally associated with Arbitrary-Lagrangian-Eulerian (ALE) based, moving mesh methods for FSI. Our partitioned solution algorithm uses separate solvers for the fluid (finite volume method) and the structure (finite element method), with mesh motion computed only on a subset of component grids of our overset grid assembly. Our results indicate a significant reduction in computational cost for the mesh motion, and element quality is improved. Numerical studies of the benchmark test demonstrate the benefits of our overset mesh method over traditional approaches. 展开更多
关键词 Overset Grid Fluid-Structure Interaction Arbitrary-Lagrangian EULERIAN FINITE Volume FINITE Element Moving MESH OPENFOAM
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Accurate laser skin perforation technique aimed at promoting bleeding and reducing pain
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作者 Han-Chao Chang Yu-Hsuan Lin Kuo-Cheng Huang 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2015年第6期9-16,共8页
Laser skin perforation is an effective and promising technique for use in blood collection.In this study,the relation between the perforation profile of skin and laser irradiation at various energies is discussed.Incr... Laser skin perforation is an effective and promising technique for use in blood collection.In this study,the relation between the perforation profile of skin and laser irradiation at various energies is discussed.Increasing laser energy does not uniformly expand the size and depth of a hole because the shallow depth of field(DOF)of the focused light primarily concentrates energy on the skin surface.In practice,the hole gradually transforms from a semielliptical shape to an upsidedown avocado shape as the laser energy increases.This phenomenon can increase the amount of bleeding and reduce pain.The findings support the feasibility of developing an accurate laser skin perforation method. 展开更多
关键词 Laser skin perforation blood collection Er YAG laser DIABETIC
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Microstructure and properties of MOCVD-derived Gd_xY_(1-x)Ba_2Cu_3O_(7-δ) films with composition fluctuations
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作者 Yu-Xi Zhang Fei Zhang +5 位作者 Rui-Peng Zhao Yan Xue Hui Wang Qiu-Liang Wang Jie Xiong Bo-Wan Tao 《Rare Metals》 SCIE EI CAS CSCD 2018年第8期675-681,共7页
The effects of Gd content on crystalline orientation, microstructure and superconductivity of GdxYl-x-BazCu3O7-δ(GdYBCO) films were systematically investigated. By varying the Gd content in the liquid precursor wit... The effects of Gd content on crystalline orientation, microstructure and superconductivity of GdxYl-x-BazCu3O7-δ(GdYBCO) films were systematically investigated. By varying the Gd content in the liquid precursor without changing the total amount of rare earth elements, series of GdYBCO films with x values of 0, 0.1, 0.3, 0.5, 0.7, 0.9 and 1.0 were fabricated by metal organic chemical vapor deposition (MOCVD). X-ray diffraction (XRD) and scanning electron microscope (SEM) analysis revealed that Gd introducing could restrain the formation of CuYOa phase, but induce a-axis growth of GdYBCO film. The increase of x from 0 to 0.5 leads to enhancing critical current density at self-field and 77 K (Jcs0 from 1.8 to 2.8 MA.cm^-2, which benefits from the decrease in CuYO2 impurities and improvement of in-plane texture from 5.0° to 4.3°. However, raising x from 0.5 to 1.0 gives rise to abundant a-axis growth of film and degradation of in-plane texture from 4.3° to 5.4°, consequently resulting in the decrease OfJcsf from 2.8 to 0.8 MA.cm^-2. Even though Jcsf has not varied monotonically, the critical transition temperature of GdYBCO films linearly increases from 90.75 to 92.25 K and the in-field performance at magnetic field (B) of 0-1.1 T and 77 K as well as B parallel to film normal is also superior with Gd content increasing. 展开更多
关键词 Gd content GdYBCO MOCVD Microstructure Flux pinning
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Estimation Performance for the Cubature Particle Filter under Nonlinear/Non-Gaussian Environments
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作者 Dah-Jing Jwo Chien-Hao Tseng 《Computers, Materials & Continua》 SCIE EI 2021年第5期1555-1575,共21页
This paper evaluates the state estimation performance for processing nonlinear/non-Gaussian systems using the cubature particle lter(CPF),which is an estimation algorithm that combines the cubature Kalman lter(CKF)and... This paper evaluates the state estimation performance for processing nonlinear/non-Gaussian systems using the cubature particle lter(CPF),which is an estimation algorithm that combines the cubature Kalman lter(CKF)and the particle lter(PF).The CPF is essentially a realization of PF where the third-degree cubature rule based on numerical integration method is adopted to approximate the proposal distribution.It is benecial where the CKF is used to generate the importance density function in the PF framework for effectively resolving the nonlinear/non-Gaussian problems.Based on the spherical-radial transformation to generate an even number of equally weighted cubature points,the CKF uses cubature points with the same weights through the spherical-radial integration rule and employs an analytical probability density function(pdf)to capture the mean and covariance of the posterior distribution using the total probability theorem and subsequently uses the measurement to update with Bayes’rule.It is capable of acquiring a maximum a posteriori probability estimate of the nonlinear system,and thus the importance density function can be used to approximate the true posterior density distribution.In Bayesian ltering,the nonlinear lter performs well when all conditional densities are assumed Gaussian.When applied to the nonlinear/non-Gaussian distribution systems,the CPF algorithm can remarkably improve the estimation accuracy as compared to the other particle lterbased approaches,such as the extended particle lter(EPF),and unscented particle lter(UPF),and also the Kalman lter(KF)-type approaches,such as the extended Kalman lter(EKF),unscented Kalman lter(UKF)and CKF.Two illustrative examples are presented showing that the CPF achieves better performance as compared to the other approaches. 展开更多
关键词 Nonlinear estimation NON-GAUSSIAN Kalman lter unscented Kalman lter cubature particle filter
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Valuation and Determination of Seven and Five Parameters of Photovoltaic Generator by Iterative Method 被引量:1
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作者 Ahmed Yahfdhou M. M. Menou +3 位作者 A. M. Yahya Ne. D. Eida A. K. Mahmoud Issakha Youm 《Smart Grid and Renewable Energy》 2016年第9期247-260,共14页
The mathematical modeling of solar cells is essential for any optimization operation of the efficiency or the diagnosis of photovoltaic generator. The photovoltaic module is generally represented by an equivalent circ... The mathematical modeling of solar cells is essential for any optimization operation of the efficiency or the diagnosis of photovoltaic generator. The photovoltaic module is generally represented by an equivalent circuit whose parameters are experimentally calculated by using the characteristic current-tension, I-V. The precise determination of these parameters stays a challenge for the researchers, making to a big difference in the models and the digital methods dedicated to their characterizations. In the present paper, We are interested to characterize the parameters of single diode and two diodes models, in order to plan the behavior of the photovoltaic generator under real functioning conditions. We developed an identification method of the parameters using Newton Raphson method by using the software Matlab/Simulink. This method is the faster technique which allows the identification of several parameters and can be used in real time applications. The results of the proposed method show an accordance with the experimental and simulated characteristics of photovoltaic generator. 展开更多
关键词 Extraction Parameters One and Two Diode Model Iterative Method Power of Generator PV
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A Note on the Derivation of Wave Action Balance Equation in Frequency Space
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作者 Tai-Wen HSU Jian-Ming LIAU +2 位作者 Shin-Jye LIANG Shan-Hwei OU Yi-Ting LI 《China Ocean Engineering》 SCIE EI 2011年第1期133-138,共6页
In this paper the wave action balance equation in terms of frequency-direction spectrum is derived. A theoretical formulation is presented to generate an invariant frequency space to replace the varying wavenumber spa... In this paper the wave action balance equation in terms of frequency-direction spectrum is derived. A theoretical formulation is presented to generate an invariant frequency space to replace the varying wavenumber space through a Jacobian transformation in the wave action balance equation. The physical properties of the Jacobian incorporating the effects of water depths are discussed. The results provide a theoretical basis of wave action balance equations and ensure that the wave balance equations used in the SWAN or other numerical models are correct. It should be noted that the Jacobian is omitted in the wave action balance equations which are identical to a conventional action balance equation. 展开更多
关键词 wave action balance equation wavenumber-spectrum frequency-spectrum JACOBIAN
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Taxpayers Fraudulent Behavior Modeling The Use of Datamining in Fiscal Fraud Detecting Moroccan Case
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作者 Farid Ameur Mohamed Tkiouat 《Applied Mathematics》 2012年第10期1207-1213,共7页
The fraudulent behavior of taxpayers impacts negatively the resources available to finance public services. It creates distortions of competition and inequality, harming honest taxpayers. Such behavior requires the go... The fraudulent behavior of taxpayers impacts negatively the resources available to finance public services. It creates distortions of competition and inequality, harming honest taxpayers. Such behavior requires the government intervention to bring order and establish a fiscal justice. This study emphasizes the determination of the interactions linking taxpayers with tax authorities. We try to see how fiscal audit can influence taxpayers’ fraudulent behavior. First of all, we present a theoretical study of a model pre established by other authors. We have released some conditions of this model and we have introduced a new parameter reflecting the efficiency of tax control;we found that the efficiency of a fiscal control have an important effect on these interactions. Basing on the fact that the detection of fraudulent taxpayers is the most difficult step in fiscal control, We established a new approach using DATA MINING process in order to improve fiscal control efficiency. We found results that reflect fairly the conduct of taxpayers that we have tested based on actual statistics. The results are reliable. 展开更多
关键词 TAX FRAUD TAX Evasion Data Mining Knowledge Discovery in Databases (KDD) FISCAL Policy FISCAL Reform FISCAL Control FISCAL Justice TAXPAYERS TAX Administration
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Prevalence of cercarial infections in freshwater snails and morphological and molecular identification and phylogenetic trends of trematodes
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作者 Chadaporn Dunghungzin Thapana Chontananarth 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2020年第10期439-447,共9页
Objective:To investigate the prevalence of cercarial infections in freshwater snails from several water sources in Nakhon Nayok,Nonthaburi,and Pathum Thani provinces of Central Thailand,and to reconstruct a phylogenet... Objective:To investigate the prevalence of cercarial infections in freshwater snails from several water sources in Nakhon Nayok,Nonthaburi,and Pathum Thani provinces of Central Thailand,and to reconstruct a phylogenetic tree for improved understanding of the relationships in the cercarial stage.Methods:The snail specimens were collected from 34 total sampling sites and investigated for cercarial infections using the crushing method.The cercarial specimens were classified and used for the phylogenetic tree analysis using the Internal Transcribed Spacer 2(ITS2).Results:A total of 1921 snail specimens were classified into five families and seven species.The results showed that four snail species were identified as intermediate hosts of the larval stages of trematodes,with an overall prevalence of infection of 2.45%(47/1921).The infected snail specimens included five groups of the cercarial type:cercariaeum cercariae,echinostome cercaria,megalurous cercaria,parapleurolophocercous cercaria,and xiphidiocercariae.This is particularly true of xiphidiocercariae,which was found to be the dominant type among cercarial infections in bithyniid snails by approximately 38.00%.With regard to molecular identification,the phylogenetic tree was reconstructed using the neighbor-joining method with 10000 bootstraps and separated the trematodes into three clades:Echinostomatoidea,Microphalloidea and Opisthorchioidea.Conclusions:The study reveals a high prevalence of cercarial infection for each cercarial type and maturation into a definite trematode genus and delineates morphological characteristics and evolutionary trends among each larval trematode in Nakhon Nayok,Nonthaburi and Pathum Thani provinces.In addition,the ITS2 sequence data of cercariae could be used to examine classification of these species at the family level. 展开更多
关键词 CERCARIA Freshwater snails Molecular identification Phylogenetic tree PREVALENCE Thailand
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