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无根之花,风流自渡——评叶弥《风流图卷》
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作者 相宜 《扬子江(评论)》 CSSCI 北大核心 2019年第2期49-52,共4页
在动荡奔涌的生命长河中,漂泊的人心从此岸出发,始终渴望抵达彼岸得到安宁。在生活日常与无常的相伴中寻找自我,在吞咽世界的荒诞与惊奇的同时感知自我,然后在时间缓慢又迅猛的流逝中接受自我。每个人兜兜转转、寻寻觅觅的一生是学习成... 在动荡奔涌的生命长河中,漂泊的人心从此岸出发,始终渴望抵达彼岸得到安宁。在生活日常与无常的相伴中寻找自我,在吞咽世界的荒诞与惊奇的同时感知自我,然后在时间缓慢又迅猛的流逝中接受自我。每个人兜兜转转、寻寻觅觅的一生是学习成长的过程,也可谓是摆渡自己的旅程。作家叶弥一向关注现世人类的成长期,无论是青春期肉体的迷茫躁动,还是精神世界与成人话语的对垒,各色人物在她笔下灵动又倔强地破土而出,脆弱又坚强地生长起来。 展开更多
关键词 图卷 长河 兜兜 生活 生命 评叶 风流
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GIS based land suitability assessment along Laos-China border 被引量:4
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作者 占达黑马万 吴次芳 +1 位作者 叶艳梅 Y.Ayumi 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第3期343-349,398,共8页
Assessment of the forest land use change and proposed land suitability for tea for the area along Laos – China Border were the main purpose of this research paper. An integrated GIS-based analysis system (IGAS), su... Assessment of the forest land use change and proposed land suitability for tea for the area along Laos – China Border were the main purpose of this research paper. An integrated GIS-based analysis system (IGAS), supporting assessment of forest land-use and land suitability for the study area where along Laos-China border was developed. Multi criteria analysis and system dynamics techniques were used to assess forest land use and land suitability and to forecast potential land-use for tea. The total study area is estimated at 10 325.07 km2 according to the field data collection and data analysis. The area of current forest cover decreased rapidly from 6337.33 km2 (61.38%) in 1992 to 5106.28 km2 (49.46%) in 2002 in the study area. The current forest was mainly trans-ferred to potential forest and permanent agriculture especially to rubber plantation areas even in the National Conservation Biodiversity Conser-vation Areas. The main causes of forest land use change are poverty. In order to address the problems, land suitability classification for tea was developed based on the multi-criteria. And finally two options of land suitability classification for tea for the study areas were developed. 展开更多
关键词 FOREST Land evaluation Phongsaly Laos TEA
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Habitat suitability analysis of eelgrass Zostera marina L. in the subtidal zone of Xiaoheishan Island 被引量:3
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作者 周健 王其翔 +2 位作者 赵文溪 于道德 官曙光 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第1期69-78,共10页
We present a GIS-based habitat suitability index(HSI) model to identify suitable areas for Zostera marina L. restoration in the subtidal zone of Xiaoheishan Island. The controlling factors in the model,in order of imp... We present a GIS-based habitat suitability index(HSI) model to identify suitable areas for Zostera marina L. restoration in the subtidal zone of Xiaoheishan Island. The controlling factors in the model,in order of importance,are Secchi depth,sediment composition,water temperature,salinity,current velocity,water depth and nutrient quality. Specific factor piecewise functions have been used to transform parameter values into normalized quality indexes. The weight of each factor was defined using expert knowledge and the analytic hierarchy process(AHP) method. All of the data thus obtained were interpolated using the inverse distance weighted(IDW) interpolation method to create maps for the entire region. In this study,the analysis of habitat suitability in the subtidal zone of Xiaoheishan Island was conducted for four seasons. According to the GIS-based HSI model,the optimal habitat of Z ostera marina L. appears in spring,although habitat remains suitable all year round. On the whole,the optimum site for eelgrass restoration is located in the eastern region,followed by the western and southern regions. We believe that the GIS-based HSI model could be a promising tool to select sites for Z ostera marina L. restoration and could also be applicable in other types of habitat evaluation. 展开更多
关键词 Zostera marina L. habitat suitability index (HSI) model RESTORATION subtidal zone
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Probabilistic SDG model description and fault inference for large-scale complex systems 被引量:4
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作者 杨帆 Xiao Deyun 《High Technology Letters》 EI CAS 2006年第3期239-244,共6页
Large-scale complex systems have the feature of including large amount of variables that have complex relationships, for which signed directed graph (SDG) model could serve as a significant tool by describing the ca... Large-scale complex systems have the feature of including large amount of variables that have complex relationships, for which signed directed graph (SDG) model could serve as a significant tool by describing the causal relationships among variables. Although qualitative SDG expresses the causing effects between variables easily and clearly, it has many disadvantages or limitations. Probabilistic SDG proposed in the article describes deliver relationships among faults and variables by conditional probabilities, which contains more information and performs more applicability. The article introduces the concepts and con- struction approaches of probabilistic SDG, and presents the inference approaches aiming at fault diagnosis in this framework, i.e. Bayesian inference with graph elimination or junction tree algorithms to compute fault probabilities. Finally, the probabilistic SDG of a typical example of 65t/h boiler system is given. 展开更多
关键词 signed directed graph (SDG) hazard assessment fault diagnosis Bayesian network
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Prediction of risk of cardiovascular events in patients with mild to moderate coronary artery lesions using naive Bayesian networks 被引量:2
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作者 Wei WANG Xian-Tao SONG +7 位作者 Yun-Dai CHEN Xing-Sheng YANG Feng XU Min ZHANG Kai TAN Fei YUAN Dong LI Shu-Zheng LYU 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2016年第11期899-905,共7页
Background This prospective study integrated multiple clinical indexes and inflammatory markers associated with coronary atherosclerotic vulnerable plaque to establish a risk prediction model that can evaluate a patie... Background This prospective study integrated multiple clinical indexes and inflammatory markers associated with coronary atherosclerotic vulnerable plaque to establish a risk prediction model that can evaluate a patient with certain risk factors for the likelihood of the occurrence of a coronary heart disease event within one year. Methods This study enrolled in 2686 patients with mild to moderate coronary artery lesions. Eighty-five indexes were recorded, included baseline clinical data, laboratory studies, and procedural characteristics. During the 1-year follow-up, 233 events occurred, five patients died, four patients suffered a nonfatal myocardial infarction, four patients underwent revascularization, and 220 patients were readmitted for angina pectoris. The Risk Estimation Model and the Simplified Model were conducted using Bayesian networks and compared with the Single Factor Models. Results The area under the curve was 0.88 for the Bayesian Model and 0.85 for the Simplified Model, while the Single Factor Model had a maximum area under the curve of 0.65. Conclusion The new models can be used to assess the short-term risk of individual coronary heart disease events and may assist in guiding preventive care. 展开更多
关键词 Bayesian networks Cardiovascular events PREDICTION
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Quality Evaluation and Comprehensive Analysis of Flue-cured Tobacco Leaf in Fuzhou 被引量:2
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作者 冯小虎 李琰琰 《Agricultural Science & Technology》 CAS 2016年第1期168-174,共7页
The appearance quality, physical properties, chemical components and sensory quality of 69 flue-cured tobacco leaf samples from 6 counties of Fuzhou City in 2013 were analyzed and evaluated, and were compared with tho... The appearance quality, physical properties, chemical components and sensory quality of 69 flue-cured tobacco leaf samples from 6 counties of Fuzhou City in 2013 were analyzed and evaluated, and were compared with those in southeast area of China. The results showed that the flue-cured tobacco leaves in Fuzhou in 2013 had better hygroscopicity, toughness and filling ability, as well as suitable dragging force. However, some of the tobacco leaves were slightly thin, and had relatively high stem ratio. The tobacco leaves in Fuzhou had higher potassium content, lower starch content, and higher potassium to chlorine ratio. The middle tobacco leaves had better coordination of chemical components and general sensory quality(medium to medium-super level). Most upper and middle flue-cured tobacco leaf samples had medium-super aroma quality, relatively sufficient aroma quantity,and relatively concentrated smoke; while the lower flue-cured tobacco leaves had little aroma quantity and insufficient smoke. The appearance quality score of lower tobacco leaf samples in Fuzhou in 2013 was slightly lower than that in southeastand whole China. The scores of maturity and leaf structure of middle tobacco leaves in Fuzhou were equivalent to those in southeast China and the national averages.The upper leaves in Fuzhou obtained an equivalent score in oil content and slightly lower scores in other indexes as compared with those in southeast China.The middle-lower tobacco leaves in Fuzhou had better hygroscopicity and toughness compared with those in southeastand whole China. The total alkaloid content per plant andreducing sugar content and potassium content in the middle and lower parts were higher than those in southeast and whole China. However, the scores of coordination of chemical components of lower and upper tobacco leaves in Fuzhou were slightly lower than those in southeast and whole China. The sensory quality of the 3 parts of tobacco leaves in Fuzhou were similar to that in southeast and whole China, but the score of consistency of upper tobacco leaves in Fuzhou was slightly higher. 展开更多
关键词 Fuzhou Tobacco quality Chemical component Analysis and evaluation
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Assessing Adaptability of Planted Trees Using Leaf Traits: A Case Study with Robinia pseudoacacia L. in the Loess Plateau, China 被引量:3
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作者 JIN Tiantian LIU Guohua +2 位作者 FU Bojie DING Xiaohui YANG Lei 《Chinese Geographical Science》 SCIE CSCD 2011年第3期290-303,共14页
Leaf trait patterns and their variations with climate are interpreted as an adaptive adjustment to environment.This study assessed the adaptability of planted black locust (Robinia pseudoacacia L.) based on the analys... Leaf trait patterns and their variations with climate are interpreted as an adaptive adjustment to environment.This study assessed the adaptability of planted black locust (Robinia pseudoacacia L.) based on the analysis of leaf traits and the comparison of its leaf traits with inter-specific ones existing in the same area.We measured some water and N use related leaf traits: leaf dry mass per unit area (LMA) and N,P and K concentrations based on both leaf area (Narea,Parea and Karea) and leaf mass (Nmass,Pmass and Kmass) of R.pseudoacacia at 31 sites along a water stress gradient in North Shaanxi Province,China.The results show that leaves of R.pseudoacacia have high Nmass and low LMA in the study area.High Nmass and low LMA are usually representative of luxurious resource use,and will advance plant resource competitiveness in high-resource conditions.As a whole,LMA-nutrient relationships of R.pseudoacacia display patterns that are fairly similar to the inter-specific relationships in both direction and intensity.The tendency for LMA and Narea to increase with decreasing water availability and the positive correlation between LMA and Narea reflect the trend for R.pseudoacacia to enhance water use efficiency (WUE) at the expense of down-regulated photosynthetic N use efficiency (PNUE) and high construction cost in dry conditions.However,the positive relationship between LMA and Narea in high mean annual precipitation (MAP) area is either unremarkable or reversed with decreasing water availability.This implies a lower photosynthetic capacity and a higher construction cost for high-LMA leaves.The inter-specific relationship between LMA and Narea is positive and does not change with water availability.This difference between inter-species and intra-species may be due to more diversified anatomies and more specialised structures for inter-species than intra-species.The failure of R.pseudoacacia adaption to dry conditions reflected by LMA-Narea relationship may be partially responsible for the emergence of rampike and dwarf forms found frequently in dry conditions.Incorporating intrinsic characteristics of planted trees into vegetation restoration project will be instructive and meaningful for species selection. 展开更多
关键词 water stress planted tree leaf trait Robinia pseudoacacia L. TRADEOFF Loess Plateau
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Evaluation the effect of fertility-preserving surgery on young patients with malignant ovarian tumors
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作者 Minmin Hou Mingrong Xi Zeyi Cao Xiaoyu Niu Zhilan Peng Hongjing Wang Ai Zheng 《The Chinese-German Journal of Clinical Oncology》 CAS 2006年第6期446-450,共5页
Objection: To evaluate the impact of fertility-preserving surgery and adjuvant chemotherapy on survival and fertility of young patients with ovarian malignant tumors. Methods: Retrospective analysis of 39 patients w... Objection: To evaluate the impact of fertility-preserving surgery and adjuvant chemotherapy on survival and fertility of young patients with ovarian malignant tumors. Methods: Retrospective analysis of 39 patients with ovarian malignant germ cell tumors, 23 patients with malignant epithelial tumors and 4 patients with sexual cord mesenchymal tumors receiving conservative treatments. Results: Two patients lost follow-up (we do not statistics them). Fifty-nine among 64 patients were alive up to now (92.19%). The overall survival rate for ovarian epithelial malignancies, malignant germ cell tumors and sexual cord mesenchymal tumors were 95.45%, 89.47% and 100% respectively. Fifteen patients received second operation and recurrence was found in 6 patients. Among the 59 surviving patients, 53 patients have normal menstruation. Thirteen patients among 20 patients who want to pregnant have 15 pregnancies and 9 successful deliveries. Conclusion: The management of fertility-preserving surgery on patients with ovarian malignant germ cell tumors, whatever the FIGO staging is, is a safe option. For patients with ovarian epithelial carcinomas, fertility-preserving surgery only confined to low-stage (stage Ⅰ), low-grade (G1), and patients who want keep fertility function seriously. Cisplatinum-based combination chemotherapy is necessary. Standardized chemotherapy has no affection on fertility function. 展开更多
关键词 ovarian malignant tumor fertility-preserving young patients ovarian function
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Joannesia princeps: Evaluation of Aqueous Extracts Genotoxicity Utilizing Allium cepa Assay and Micronucleus Test 被引量:1
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作者 Viviane Moreira de Lima Jessica Tamara dos Santos Teixeira +7 位作者 Jennifer Vieira Gomes Lelio Kallut Almeida Netto Leonardo Oliveira Bastos Hataanderson Luiz Cabral dos Santos Lenicio Gongalves Francisco de Assis da Silva Bruno Pereira Berto Helcio Resende Borba 《Journal of Life Sciences》 2013年第12期1249-1254,共6页
Evaluation of the genotoxic and cytotoxic potentials is a part of the analysis process where plant products with therapeutic properties must be submitted for being safely employed, mainly through long time points, doa... Evaluation of the genotoxic and cytotoxic potentials is a part of the analysis process where plant products with therapeutic properties must be submitted for being safely employed, mainly through long time points, doannesia princeps, also known as "cotieira" has been used on popular medicine as laxative and several diseases treatment. Aiming to analyze genotoxic potential ofd. princeps leaves extract, Allium cepa assay and micronucleus test were employed. No genotoxic activity presented J. princeps leaves extract; however, extracts cytotoxic activity over A. cepa meristematic cells and mice marrow cells was observed. J. princeps leaves extract presented antiproliferative activity at concentrations and systems employed indicating their therapeutic potential for cellular cycle inhibition. Moreover, results showed that in regard to its mutagenic effect, usage of J. princeps leaves tea on popular medicine has been a safe procedure, as well. 展开更多
关键词 CYTOTOXICITY GENOTOXICITY Allium cepa assay MICRONUCLEUS Joannesia princeps.
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A FREQUENCY OFFSET ESTIMATION ALGORITHM FOR OFDM SYSTEMS
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作者 Fang Zhi Xiao Wan'ang Shi Yin 《Journal of Electronics(China)》 2008年第1期1-6,共6页
A new fine carrier frequency offset estimation algorithm in Orthogonal Frequency Division Multiplexing (OFDM) system is proposed. The correlation item is the training sequence instead of the received signal in the new... A new fine carrier frequency offset estimation algorithm in Orthogonal Frequency Division Multiplexing (OFDM) system is proposed. The correlation item is the training sequence instead of the received signal in the new algorithm. Simulation results show that the performance of the new algo- rithm is 4dB-9dB better than that of Schmidl's algorithm. Coarse frequency offset estimation is also discussed in this paper, which is the improvement of Zhang's method. The estimation range using the improvement method is twice as that using the Zhang's method. Based on the hardware of the receiver and the improved algorithm, a method using Fast Fourier Transform (FFT) is proposed to implement the coarse frequency estimation. The chip area of OFDM system can be reduced by using the proposed method. 展开更多
关键词 Orthogonal Frequency Division Multiplexing (OFDM) Frequency offset estimation Fast Fourier Transform (FFT)
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The investigation on two-dimensional pilot-symbol-aided channel estimation method for OFDM system
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作者 孙居颖 Zhang Yanhua 《High Technology Letters》 EI CAS 2008年第4期364-369,共6页
Channel estimation for orthogonal frequency division multiplexing (OFDM) system has attracteo widespread attention. In this paper, a novel efficient two-dimensional (2-D) channel estimation algorithm based on fast... Channel estimation for orthogonal frequency division multiplexing (OFDM) system has attracteo widespread attention. In this paper, a novel efficient two-dimensional (2-D) channel estimation algorithm based on fast Fourier transform (FFT) is proposed for a time-variant, frequency-selective wideband wireless channel. Both theoretical analysis and simulation results are addressed in the paper. The simulation results prove that the proposed algorithm has simpler implementation, better performance and wider application than other traditional deeision-direeted algorithms. 展开更多
关键词 orthogonal frequency division multiplexing (OFDM) fast Fourier transfoml (FFF) channel estimation
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Constrained Bayesian Method for Testing the Directional Hypotheses
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作者 Kartlos J. Kachiashvili N. K. Bansal I. A. Prangishvili 《Journal of Mathematics and System Science》 2018年第4期96-118,共23页
The paper discusses the generalization of constrained Bayesian method (CBM) for arbitrary loss functions and its application for testing the directional hypotheses. The problem is stated in terms of false and tru... The paper discusses the generalization of constrained Bayesian method (CBM) for arbitrary loss functions and its application for testing the directional hypotheses. The problem is stated in terms of false and true discovery rates. One more criterion of estimation of directional hypotheses tests quality, the Type III errors rate, is considered. The ratio among discovery rates and the Type III errors rate in CBM is considered. The advantage of CBM in comparison with Bayes and frequentist methods is theoretically proved and demonstrated by an example. 展开更多
关键词 CBM Bayesian test hypotheses testing false discovery rate type error rate.
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Evaluation of Surface Water Availability for Inland Valleys Rice Production: The Case of Mankran Watershed in a Deciduous Forest Zone of Ghana
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作者 Busia N. Dawuni Regassa Namara +1 位作者 Fred Kizito Hideto Fujii 《Journal of Environmental Science and Engineering(B)》 2012年第2期250-259,共10页
In Ghana, inland valleys have been found to be suitable for rice cultivation and could potentially increase lowland paddy rice production, This study estimated the temporal variations of surface water resources and th... In Ghana, inland valleys have been found to be suitable for rice cultivation and could potentially increase lowland paddy rice production, This study estimated the temporal variations of surface water resources and their spatial distribution in the Mankran watershed of Ghana through the collection of recorded hydrological data in the bench mark watershedfrom2008 to 2010. Since most inland valley rice cultivation highly depends on rainfall, the watershed precipitation data over a decadal period showed sufficient wet years with a potential to sustain a high cultivation of paddy rice. Peak wetness occurred in June and October over a bi-modal precipitation pattern. Rating curve data for the Mankran-kesse river-upstream depicted low discharge values despite having a higher stream order. Thus stream order alone was not sufficient to estimate water resources potential. It was presumed that the geomorphology and lithology of the highly porous river bed and the presence of high sub-surface water resources stored in this zone may be implicated for this observation. Provision of water storage options for zones like Kesse-upstream seems a feasible option in order to cater for supplementary irrigation while indirectly tapping on subsurface water resources stored in the porous aquifers through basin interflows. Base flow data also showed that the discharge from upstream locations to the downstream exit of the watershed was high through direct surface river discharge and subsurface interflow. The temporal patterns of the hydrology indicate that annual paddy rice cultivation is ideal between May and October. 展开更多
关键词 Mankran watershed inland valleys surface water availability rice production.
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Radium isotopes assess water mixing processes and its application in the Zhujiang River estuary
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作者 郭肖伊 许博超 +6 位作者 于志刚 李秀芹 南海明 简慧敏 江雪艳 刁少波 高茂生 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第5期1108-1116,共9页
Radium (Ra) isotopes are useful for tracing water mass transport and examining estuarine hydrological dynamics. In this study, several hydrological parameters, nutrients, ehlorophyll-a (ehl-a), suspended particula... Radium (Ra) isotopes are useful for tracing water mass transport and examining estuarine hydrological dynamics. In this study, several hydrological parameters, nutrients, ehlorophyll-a (ehl-a), suspended particulate matter (SPM) and Ra isotopes (223Ra, 224Ra and 226Ra) of surface waters of the Zhujiang (Pearl) River estuary (ZRE) were measured. This was done for both winter (December) and summer (July) seasons, to quantitatively understand the seasonal characteristics of river plume flow rate and trajectories, as well as the ecological response. The results show that Ra concentrations in summer were higher than in winter, especially Z24Ra (about 2-5 times higher). The spatial distribution of three Ra isotopes and relative Ra water ages indicated that river water mainly flushed out of ZRE through the western side in winter, where the water transport was about 5 days faster than in the eastern zone. In summer, diluted river water expended to the east side, resulting in fairly similar water ages for both sides of the river mouth. Although nutrients were higher during the summer season, lower chl-a concentrations indicated that reduced primary production might be caused by high SPM (low light penetration). The results obtained from this study will provide knowledge needed for effectively developing and managing the ZRE. 展开更多
关键词 Zhujiang River estuary radium isotopes water ages NUTRIENTS
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Numerical assessment on improving multistage centrifugal impeller performance by changing inlet skew angle at impeller inlet 被引量:2
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作者 M.N.Labib Woo Ju-sik +4 位作者 Choi Du-youl T.Utomo B.Fajar Chung Han-shik Jeong Hyo-min 《Journal of Central South University》 SCIE EI CAS 2012年第4期953-961,共9页
Multistage centrifugal impellers with four different skew angles were investigated by using computational fluid dynamics.The purpose of this work is to investigate the influences of lean angle at the blade tip of the ... Multistage centrifugal impellers with four different skew angles were investigated by using computational fluid dynamics.The purpose of this work is to investigate the influences of lean angle at the blade tip of the impeller inlet.Four variations of lean angles,that is,8°,10°,15° and 20°,were made at first stage impeller.Reynolds Average Navier Stokes equation was used in simulation together with a shear?stress transport(SST) k-w turbulence model and mixing-plane approach,respectively.Three dimensional fluid flows were simplified using periodic model to reduce the computational cost and time required.A good performance was expected that the secondary flow can be effectively reduced in the flow passage of the impeller without excessive increase in manufacturing cost caused by the secondary flow.The results show that secondary flow affects the main flow intricately to form vortices or having non-uniform velocity in the flow passage,which in turn results in substantial fluid energy loss not only in the impeller but also in the guide vane downstream of impeller.The numerical solutions were performed and allowed the optimum design and operating conditions to be obtained. 展开更多
关键词 computational fluid dynamics secondary flow blade inlet skew angle multistage centrifugal compressor
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A Review on the Identification Indicators of Tea Germplasm
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作者 J. M. Tang Y. S. Li Q Tang 《Journal of Agricultural Science and Technology(B)》 2011年第1期1-7,共7页
Tea plant is cross pollinated plant, it forms a variety of the tea Germplasm constantly in the long-term breeding process. Tea Germplasm resources are the material foundation for improving varieties and also the basic... Tea plant is cross pollinated plant, it forms a variety of the tea Germplasm constantly in the long-term breeding process. Tea Germplasm resources are the material foundation for improving varieties and also the basic research which is good for developing and expanding tea well-bred varieties in tea field, especially in quality selection and biotechnology research. Furthermore, excellent tea germplasm is primary condition for tea breeding and quality. Therefore, identification and screening excellent tea germplasm become particularly important. We need accelerate develop high-quality tea varieties, and it need to base on exploring and studying tea germplasm. This paper reviews the research progress of tea germplasm on identification from morphological characteristic, biological characteristic, quality characteristic, resistance and heredity. However, there are still some problems on identification and screening of tea germplasm, no effective methods have been found so far which apply on early identification and genetic engineering, so we should make intensive and long lasting study tea germplasm and analyze systematically various identification, which are benefit for breeding high-quality seeds, shortening the breeding period and summing the new way of breeding. We expect them to play the key roles and provide the theory basis for genetic improvement, classification and breeding in tea plant. 展开更多
关键词 TEA germplasm resources identification indicators review.
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Assessment Method of Heavy NC Machine Reliability Based on Bayes Theory 被引量:1
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作者 张雷 王太勇 胡占齐 《Transactions of Tianjin University》 EI CAS 2016年第2期105-109,共5页
It is difficult to collect the prior information for small-sample machinery products when their reliability is assessed by using Bayes method. In this study, an improved Bayes method with gradient reliability(GR) resu... It is difficult to collect the prior information for small-sample machinery products when their reliability is assessed by using Bayes method. In this study, an improved Bayes method with gradient reliability(GR) results as prior information was proposed to solve the problem. A certain type of heavy NC boring and milling machine was considered as the research subject, and its reliability model was established on the basis of its functional and structural characteristics and working principle. According to the stress-intensity interference theory and the reliability model theory, the GR results of the host machine and its key components were obtained. Then the GR results were deemed as prior information to estimate the probabilistic reliability(PR) of the spindle box, the column and the host machine in the present method. The comparative studies demonstrated that the improved Bayes method was applicable in the reliability assessment of heavy NC machine tools. 展开更多
关键词 heavy NC machine reliability assessment Bayes method prior information
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Evaluation of Immunomodulatory Activity of the Herbals Formula Viranur, Turmeric (Curcuma heyneana Val.) and Phyllanthus (Phyllanthus niruri L.) in Layer Chicken Vaccinated with Avian Influenza
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作者 Sri Hartati Tri Untari +1 位作者 Ida Fitriyani Bambang Sutrisno 《Journal of Agricultural Science and Technology(A)》 2015年第8期695-702,共8页
The aim of this research was to know the effect of herbal as immunomodulator on chicken layer vaccinated with avian influenza. A total of 60 chickens were alloted into three treatment groups: control group (KA), gr... The aim of this research was to know the effect of herbal as immunomodulator on chicken layer vaccinated with avian influenza. A total of 60 chickens were alloted into three treatment groups: control group (KA), group KB and group KC, with 20 chicken each group. All the chickens were vaccinated with Newcastle disease (ND) in the age of one week, and a week later they were vaccinated with avian influenza (AI). The chickens in group KB were drunken with herbal solution containing of 5 g turmeric (Curcuma heyneana Val.) and 25 g phyllanthus (Phyllanthus niruri L.) and group KC were drunken with herbal solution containing of 36 g the herbals formula Viranur and 25 g phyllanthus (Phyllanthus niruri L.), respectively for four weeks. Thirty days after AI vaccinated, all of chicken were weighed and necropsied. Samples from bursa of Fabricius, tymus and spleen were taken for weighing and histopathological examination. The weight indexs of bursa of Fabricius, tymus and spleen were not significantly different between control group and treatment group in the considered statistically significance (P 〉 0.05), but the treatment groups (KB and KC) had higher weight index. The histopathologically changes of spleen in both control group and treatment groups were not different, although in the group KC, in bursa of Fabricius, there was lymphocyte increase in its lymphoid follicles; and in the group KB and KC, the tymus were more widening in the cortex than medulla. The conclusion of this study showed that the herbals can stimulate lymphocyte activity. 展开更多
关键词 Herbal IMMUNOMODULATOR histopathologic bursa of Fabricius THYMUS SPLEEN layer chicken AI.
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Development of Bayesian Network Models for Risk-Based Ship Design 被引量:3
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作者 Dimitris Konovessis Wenkui Cai Dracos Vassalos 《Journal of Marine Science and Application》 2013年第2期140-151,共12页
In the past fifteen years, the attention of ship safety treatment as an objective rather than a constraint has started to sweep through the whole maritime industry. The risk-based ship design (RBD) methodology, advo... In the past fifteen years, the attention of ship safety treatment as an objective rather than a constraint has started to sweep through the whole maritime industry. The risk-based ship design (RBD) methodology, advocating systematic integration of risk assessment within the conventional design process has started to takeoff. Despite this wide recognition and increasing popularity, important factors that could potentially undermine the quality of the results come from both quantitative and qualitative aspects during the risk assessment process. This paper details a promising solution by developing a formalized methodology for risk assessment through effective storing and processing of historical data combined with data generated through first-principle approaches. This method should help to generate appropriate risk models in the selected platform (Bayesian networks) which can be employed for decision making at design stare. 展开更多
关键词 risk-based ship design risk assessment data mining Bayesian networks ship safety
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Evaluating ultrasound signals of carbon steel fatigue testing using signal analysis approaches 被引量:2
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作者 M.M.Padzi S.Abdullah +2 位作者 M.Z.Nuawi S.M.Beden Z.M.Nopiah 《Journal of Central South University》 SCIE EI CAS 2014年第1期232-241,共10页
The application of ultrasound techniques to monitor the condition of structures is becoming more prominent because these techniques can detect the early symptoms of defects such as cracks and other defects.The early d... The application of ultrasound techniques to monitor the condition of structures is becoming more prominent because these techniques can detect the early symptoms of defects such as cracks and other defects.The early detection of defects is of vital importance to avoid major failures with catastrophic consequences.An assessment of an ultrasound technique was used to investigate fatigue damage behaviour.Fatigue tests were performed according to the ASTM E466-96 standard with the attachment of an ultrasound sensor to the test specimen.AISI 1045 carbon steel was used due to its wide application in the automotive industry.A fatigue test was performed under constant loading stress at a sampling frequency of 8 Hz.Two sets of data acquisition systems were used to collect the fatigue strain signals and ultrasound signals.All of the signals were edited and analysed using a signal processing approach.Two methods were used to evaluate the signals,the integrated Kurtosis-based algorithm for z-filter technique(I-kaz) and the short-time Fourier transform(STFT).The fatigue damage behaviour was observed from the initial stage until the last stage of the fatigue test.The results of the I-kaz coefficient and the STFT spectrum were used to explain and describe the behaviour of the fatigue damage.I-kaz coefficients were ranged from 60 to 61 for strain signals and ranged from 5 to 76 for ultrasound signals.I-kaz values tend to be high at failure point due to high amplitude of respective signals.STFT spectrogram displays the colour intensity which represents the damage severity of the strain signals.I-kaz technique is found very useful and capable in assessing both stationary and non-stationary signals while STFT technique is suitable only for non-stationary signals by displaying its spectrogram. 展开更多
关键词 fatigue ULTRASOUND signal analysis integrated Kurtosis-based algorithm for z-filter technique short-time Fouriertransform
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