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地貌特征点的数学描述与分析 被引量:2
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作者 魏萌 王靳辉 马朝忠 《测绘科学技术学报》 北大核心 2008年第1期21-23,27,共4页
在用等高线表示3维空间地貌形态的科学性这一问题得到解决之后,自然想到如何用数学的方法来描述地貌的各种特征点。地图中的峰、谷、鞍点对应着二元函数的极大值点、极小值点以及马鞍点,首先从地貌函数的二阶方向导数入手给出了判别它... 在用等高线表示3维空间地貌形态的科学性这一问题得到解决之后,自然想到如何用数学的方法来描述地貌的各种特征点。地图中的峰、谷、鞍点对应着二元函数的极大值点、极小值点以及马鞍点,首先从地貌函数的二阶方向导数入手给出了判别它们的一个基本条件,并且给出了判别它们的一个较强的充分性条件的简捷证明。然后从概念出发,用函数分析方法首次给出了地性线的宏观定义和微观定义,同时还给出了地性点的科学定义、性质以及与等高线曲率极值点的关系定理和证明。 展开更多
关键词 特征 方向导数 等高线 地性线 地性点 曲率极值
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Genetic Diversity of Gli-1, Gli-2 and Glu-1 Alleles in Sichuan Wheat Landraces 被引量:28
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作者 魏育明 郑有良 +2 位作者 刘登才 周永红 兰秀锦 《Acta Botanica Sinica》 CSCD 2000年第5期496-501,共6页
Genetic diversity at Gli_1, Gli_2 and Glu_1 loci was investigated in 89 Sichuan wheat (Triticum aestivum L.) landraces by using acid polyacrylamide gel electrophoresis (APAGE) and SDS_PAGE. In these landraces, a total... Genetic diversity at Gli_1, Gli_2 and Glu_1 loci was investigated in 89 Sichuan wheat (Triticum aestivum L.) landraces by using acid polyacrylamide gel electrophoresis (APAGE) and SDS_PAGE. In these landraces, a total of 32 gliadin and 3 high_molecular_weight (HMW) glutenin patterns were observed. In total, 14, 15 and 5 alleles were identified at Gli_1, Gli_2 and Glu_1, respectively. At each locus, the alleles in higher frequency were Gli_A1a (89%), Gli_B1h (46%), Gli_D1a (65%), Gli_A2a (64%), Gli_B2j (45%), Gli_D2a (48%), Glu_A1c (99%), Glu_B1b (99%) and Glu_D1a (100%). The Nei's genetic variation index (H) of Sichuan wheat landraces was 0.370?6, varying from 0 to 0.708?7. The highest genetic diversity was found at Gli_B2 locus, while the lowest was found at Glu_D1. The genetic diversity at Gli loci was higher than that of Glu_1 loci among these landraces, but it was much lower than that of modern wheat cultivars. These results indicated a narrow genetic base of Sichuan wheat landraces. In this study, “Chengdu_guangtou” had the identical gliadin and HMW_glutenin patterns with “Chinese Spring”, further supporting the proposal that “Chinese Spring” is a strain of “Chengdu_guangtou”. 展开更多
关键词 wheat LANDRACE genetic diversity gliadin alleles high_molecular_weight (HMW)_glutenin alleles
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Ohmefentanyl stereoisomers induce changes of CREB phosphorylation in hippocampus of mice in conditioned place preference paradigm 被引量:6
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作者 CANGAO LIWEICHEN 《Cell Research》 SCIE CAS CSCD 2003年第1期29-34,共6页
The present study was designed to determine the changes of phosphorylation of cAMP- response ele-ment binding protein (CREB) in hippocampus induced by ohmefentanyl stereoisomers (F9202 and F9204)in conditioned place p... The present study was designed to determine the changes of phosphorylation of cAMP- response ele-ment binding protein (CREB) in hippocampus induced by ohmefentanyl stereoisomers (F9202 and F9204)in conditioned place preference (CPP) paradigm. The results showed that mice receiving F9202 and F9204displayed obvious CPP. They could all significantly stimulate CREB phosphorylation and maintained for along time without affecting total CREB protein levels. The effect of F9204 was similar to morphine whicheffect was more potent and longer than F9202. We also examined the effects of ketamine, a noncompetitiveN-mthyl-D-aspartate receptor (NR) antagonist, on morphine-, F9202- and F9204- induced CPP and phos-phorylation of CREB in hippocampus. Ketamine could suppress not only the place preference but also thephosphorylation of CREB produced by morphine, F9202 and F9204. These findings suggest that alterationsin the phosphorylation of CREB be relevant to opiates signaling and the development of opiates dependence.NR antagonists may interfere with opiates dependence and may have potential therapeutic implications. 展开更多
关键词 cAMP-response element binding protein (CREB) ohmefentanyl stereo isomers OPIATES HIPPOCAMPUS conditioned place preference (CPP).
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A Highly Isolated Co-Polarized Co-Located Electric and Magnetic Dipoles and Its MIMO Performance 被引量:1
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作者 Xingning Jia Dazhi Piao 《China Communications》 SCIE CSCD 2018年第5期104-110,共7页
In this paper, a co-polarized, co-located electric and magnetic dipoles(CCEMD) with high isolation is presented. The antenna consists of a loop based on segmented line and two independent feeding ports. Two modes of t... In this paper, a co-polarized, co-located electric and magnetic dipoles(CCEMD) with high isolation is presented. The antenna consists of a loop based on segmented line and two independent feeding ports. Two modes of the antenna are exited separately, the first one has a radiation pattern equivalent to an electric dipole by exciting anti-phase current with symmetric distribution, and the second one is like a magnetic dipole by exciting uniform and in-phase currents along the loop. The antenna is fabricated and tested. Its measured common-10 d B impedance bandwidth at two ports is 280 MHz(2.32-2.6 GHz) with isolation better than 41 d B. Its MIMO performance in terms of capacity gain(CG) over the SISO system is investigated in a multipath rich environment containing two parallel PEC planes by both measurements and image theory based simulations. Results show that, in free space, the CG results are just slightly larger than 1, however, in the multipath rich channel, the CG values are very close to 2, which indicates that two separate subchannels can be achieved by the proposed CCEMD. The measured results of CG agree well with that obtained by simulation. 展开更多
关键词 high isolation loop antenna co-polarized image theory
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Application of fractal theory in detecting low current faults of power distribution system in coal mines 被引量:5
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作者 LIU Jian-hua LIANG Rui WANG Chong-lin FAN Di-peng 《Mining Science and Technology》 EI CAS 2009年第3期321-325,共5页
Single-phase low current grounding faults areoften seen in power distribution system of coal mines.These faults are difficult to reliably identify.We propose a new method of single-phase ground fault protection based ... Single-phase low current grounding faults areoften seen in power distribution system of coal mines.These faults are difficult to reliably identify.We propose a new method of single-phase ground fault protection based upon a discernible matrix of the fractal dimension associated with line currents.The method builds on existing selective protection methods.Faulted feeders are distinguished using differences in the zero-sequence transient current fractal dimension.The current signals were first processed through a fast Fourier transform and then the characteristics of a faulted line were identified using a discernible matrix.The method of calculation is illustrated.The results show that the method involves simple calculations, is easy to do and is highly accurate.It is, therefore, suitable for distribution networks having different neutral grounding modes. 展开更多
关键词 low current faults zero sequence transient current fractal dimension discernible matrix selective protection
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Direct Path Detection Method in Indoor Location 被引量:1
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作者 华虎 李征 《Journal of Donghua University(English Edition)》 EI CAS 2006年第3期97-101,共5页
A search algorithm for the detection of a direct path signal in the presence of dense multipath in indoor environment using UWB is Woposed. This algorithm is based on signal correlation and differential coefficient. S... A search algorithm for the detection of a direct path signal in the presence of dense multipath in indoor environment using UWB is Woposed. This algorithm is based on signal correlation and differential coefficient. Statistical analysis of the algorithm is given out and computer simulation results are presented to validate the effectiveness of the algorithm. The results based on the algorithm pml3osed are compared with those based on Maximum Likelihood Estimator(MLE) and Peak Tracking(PT) in the simulation which shows that this algorithm achieves the highest accuracy in most cases and gives out relatively stable results in different Signal Noise Ratio(SNR). 展开更多
关键词 direct path MULTIPATH CORRELATION indoorlocation UWB.
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Smart Prediction for Seamless Mobility in F-HMIPv6 Based on Location Based Services
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作者 rawya rizk heba nashaat 《China Communications》 SCIE CSCD 2018年第4期192-209,共18页
This paper proposed a new scheme for smooth handoff over F-HMIPv6 networks based on Location Based Services(LBS). It uses the available information about mobile node(MN) such as user mobility patterns and MN's vel... This paper proposed a new scheme for smooth handoff over F-HMIPv6 networks based on Location Based Services(LBS). It uses the available information about mobile node(MN) such as user mobility patterns and MN's velocity to reduce handoff latency. In the proposed scheme, the movement pattern of users plays an important role in the performance analysis. The proposed scheme develops LBS that records a number of mobility patterns based on user daily behavior, and exploits these information to reduce the handoff latency. The proposed scheme is analyzed and compared with F-HMIPv6 protocol. The results show that it improves the performance in terms of handoff latency, packet delivery cost, and location update cost. Specifically, the proposed scheme achieves the tradeoff between realizing a smooth handoff and minimizing the cost that is the demand for all customers of mobile services. 展开更多
关键词 Cost functions F-HMIPV6 loca-tion based services macro handoff mobilitymanagement mobility prediction.
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Selecting suitable sites for mountain ginseng(Panax ginseng)cultivation by using geographically weighted logistic regression 被引量:1
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作者 HAN Hee JANG Kwang-min CHUNG Joo-sang 《Journal of Mountain Science》 SCIE CSCD 2017年第3期492-500,共9页
With the well-being trends to pursue a healthy life, mountain ginseng(Panax ginseng) is rising as one of the most profitable forest products in South Korea. This study was aimed at evaluating a new methodology for ide... With the well-being trends to pursue a healthy life, mountain ginseng(Panax ginseng) is rising as one of the most profitable forest products in South Korea. This study was aimed at evaluating a new methodology for identifying suitable sites for mountain ginseng cultivation in the country. Forest vegetation data were collected from 46 sites and the spatial distribution of all sites was analyzed using GIS data for topographic position, landform, solar radiation, and topographic wetness. The physical and chemical properties of the soil samples, including moisture content, p H, organic matter, total nitrogen, exchangeable cations, available phosphorous, and soil texture, were analyzed. The cultivation suitability at each site was assessed based on the environmental conditions using logistic regression(LR) and geographically weighted logistic regression(GWLR) and the results of both methods were compared. The results show that the areas with northern aspect and higher levels of solar radiation, moisture content, total nitrogen, and sand ratio are more likely to be identified as suitable sites for ginseng cultivation. In contrast to the LR, the spatial modeling with the GWLR results in an increase in the model fitness and indicates that a significant portion of spatialautocorrelation in the data decreases. A higher value of the area under the receiver operating characteristic(ROC) curve presents a better prediction accuracy of site suitability by the GWLR. The geographically weighted coefficient estimates of the model are nonstationary, and reveal that different site suitability is associated with the geographical location of the forest stands. The GWLR increases the accuracy of selecting suitable sites by considering the geographical variations in the characteristics of the cultivation sites. 展开更多
关键词 Panax ginseng Site suitability Logistic regression Geographically weighted logistic regression Geographic Information System South Korea
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EARTHQUAKE RESPONSE OF SEMI RIGID FRAME WITH ROTATIONAL DAMPER
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作者 何琦 喻群 刘志强 《Transactions of Tianjin University》 EI CAS 1999年第2期30-35,共6页
The seismic behavior of frames with semi rigid connections and rotational dampers is examined.The ground acceleration due to earthquake is regarded as a stochastic process,and a pseudo excitation algorithm in frequen... The seismic behavior of frames with semi rigid connections and rotational dampers is examined.The ground acceleration due to earthquake is regarded as a stochastic process,and a pseudo excitation algorithm in frequency domain is implemented in a computer program to handle non orthogonal damping properties of the system.The computer program which incorporates detailed connection models and rotational damping models is used to investigate the effect of the connection of the semi rigid frame.It is shown from analytical studies that semi rigid frames with rotational dampers improve the seismic response of the building and may provide an effective and reliable earthquake resistant design solution. 展开更多
关键词 semi rigid frames semi rigid connections rotational dampling earthquake respond pseudo excitation algorithm
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Allometric prediction of above-ground biomass of eleven woody tree species in the Sudanian savanna-woodland of West Africa
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作者 Louis Sawadogo Patrice Savadogo +5 位作者 Daniel Tiveau Sidzabda Djibril Dayamba Didier Zida Yves Nouvellet Per Christer Oden Sita Guinko 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第4期475-481,524,共8页
Allometric models are necessary for estimating biomass in terrestrial ecosystems. Generalized allometric relationship exists for many tropical trees, but species- and region-specific models are often lacking. We devel... Allometric models are necessary for estimating biomass in terrestrial ecosystems. Generalized allometric relationship exists for many tropical trees, but species- and region-specific models are often lacking. We developed species-specific allometric models to predict aboveground biomass for 11 native tree species of the Sudanian savanna- woodlands. Diameters at the base and at breast height, with species means ranging respectively from 11 to 28 cm and 9 to 19 cm, and the height of the trees were used as predictor variables. Sampled trees spanned a wide range of sizes including the largest sizes these species can reach. As a response variable, the biomass of the trees was obtained through destructive sampling of 4 754 trees during wood harvesting. We used a stepwise multiple regression analysis with backward elimination procedure to develop models separately predicting, total biomass of the trees, stem biomass, and biomass of branches and twigs. All species- specific regression models relating biomass with measured tree dimen- sions were highly significant (p 〈 0.001). The biomass of branches and twigs was less predictable compared to stem biomass and total biomass, although their models required fewer predictors and predictor interac- tions. The best-fit equations for total above-ground biomass and stem biomass bad R2 〉 0.70, except for the Acacia species; for branches including twig biomass, R2-values varied from 0.749 for Anogeissus leiocarpa to 0.183 for Acacia macrostachya. The use of these equations in estimating available biomass will avoid destructive sampling, and aid in planning for sustainable use of these species. 展开更多
关键词 ALLOMETRY above-ground biomass indigenous woody species linear regression site specific equation
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Fault diagnosis in neutral point indirectly grounded system basedon information fusion
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作者 于飞 鞠丽叶 +2 位作者 刘喜梅 崔平远 钟秋海 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第4期434-437,共4页
In neutral point indirectly grounded systems, phase-to-ground fault is putting new demands on fault diagnosis technology. Information fusion is applied to detect the phase-to-ground fault, which integrates several sou... In neutral point indirectly grounded systems, phase-to-ground fault is putting new demands on fault diagnosis technology. Information fusion is applied to detect the phase-to-ground fault, which integrates several sources of information, including line current, line voltage, zero sequence current and voltage, and quintic harmonic wave component. This method is testified through the simulation of Matlab. Simulation results show that the precision and reliability of the detection has been greatly increased. 展开更多
关键词 information fusion fault diagnosis neutral point indirectly grounded system phase-to-ground fault
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Estimation of Soil Hydrodynamic Parameters Related to Agricultural Practices -Case of the Tougou Experimental Site (Burkina Faso)
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作者 Dial Niang Mahamadou Koita +3 位作者 Amadou Keita Medogbe Christelle Manuela Houndayi Cheick Oumar Zoure Amagana Emmanuel Dara 《Journal of Environmental Science and Engineering(A)》 2017年第10期527-534,共8页
This study aims to estimate the hydrodynamic properties of soils under various agricultural practices in the Tougou catchment in northern Burkina Faso. The methodology adopted is based on the determination of the unsa... This study aims to estimate the hydrodynamic properties of soils under various agricultural practices in the Tougou catchment in northern Burkina Faso. The methodology adopted is based on the determination of the unsaturated hydraulic conductivity and capillary sorptivity close to saturation. This method relies on the measurement of the transient infiltration flux at the soil surface with imposed hydraulic head varying from -60 to -20 mm. These tests are carried out on control, stony line, half-moon and zai plots. The results show a difference in hydrodynamic parameters according to the agricultural practices. The unsaturated hydraulic conductivity is 33.1 cm/h, 13.1 cm/h, 20.3 cm/h and 4.0 cm/h for zai, control, stony line and half-moon plots respectively. The unsaturated hydraulic conductivity is 33.1 cm/h, 13.1 cm/h, 20.3 cm/h and 4.0 cm/h for zai, control, stony line and half-moon plots respectively. The pores participating to water transfer also differ. The mean size of drainable pores is 43.7, 56.2, 22.3 and 87.2 pm on control, stony line, half-moon and zai plots respectively. 展开更多
关键词 Agricultural practice unsaturated hydraulic conductivity SORPTIVITY SOIL Tougou Burkina Faso.
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Inelastic Attenuation of Seismic Wave and Site Response near the Xiaowan Reservoir
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作者 Wu Chengdong Fu Hong Tang Shu'en 《Earthquake Research in China》 2008年第2期137-145,共9页
Based on digital seismograms recorded by 11 stations of the Xiaowan Reservoir-induced Earthquake Monitoring Network from May 21,2005 to September 2006,we calculated the inelastic attenuation near Xiaowan reservoir usi... Based on digital seismograms recorded by 11 stations of the Xiaowan Reservoir-induced Earthquake Monitoring Network from May 21,2005 to September 2006,we calculated the inelastic attenuation near Xiaowan reservoir using Atkinson method.We got the relation of Q value to frequency as Q(f)=225.8 f 0.332.Using the Moya method we got the site response of the 11 stations of Xiaowan Network and source parameters of 43 earthquakes.The source parameters were discussed briefly. 展开更多
关键词 Xiaowan reservoir Inelastic attenuation Site response
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Research on community detection algorithm based on site topic similarity and topology
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作者 Hu Yi Li Zhengmin +1 位作者 Chi Lejun Lin Jinxiu 《High Technology Letters》 EI CAS 2018年第2期189-195,共7页
Considering the deviation in content of community detection resulting from the tow accuracy of resource relevance, an algorithm based on the topology of sites and the similarity between their topics is proposed. With ... Considering the deviation in content of community detection resulting from the tow accuracy of resource relevance, an algorithm based on the topology of sites and the similarity between their topics is proposed. With topic content factors fully considered, this algorithm can search for topically similar site clusters on the premise of inter-site topology. The experimental results show that the algorithm can generate a more accurate result of detection in the real network. 展开更多
关键词 site relationship network community detection topic similarity clustering
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A Study on Neutral Point Earthed Method of Power System
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作者 Feigao Li Yanhua Meng Shaobing Shi 《International Journal of Technology Management》 2013年第3期5-7,共3页
This paper mainly is study on power system working state with neutral point different grounded methods, when the power system is normal working and the single-phase grounding. And further analysis of the different ope... This paper mainly is study on power system working state with neutral point different grounded methods, when the power system is normal working and the single-phase grounding. And further analysis of the different operating modes of voltage and current relationships, expounds the different operation occasions and characteristics. 展开更多
关键词 power system neutral point grounded methods
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Assessing Suitability of Rural Settlements Using an Improved Technique for Order Preference by Similarity to Ideal Solution 被引量:4
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作者 LIU Yanfang CUI Jiaxing +1 位作者 KONG Xuesong ZENG Chen 《Chinese Geographical Science》 SCIE CSCD 2016年第5期638-655,共18页
Land suitability assessment is a prerequisite phase in land use planning; it guides toward optimal land use by providing information on the opportunities and constraints involved in the use of a given land area. A geo... Land suitability assessment is a prerequisite phase in land use planning; it guides toward optimal land use by providing information on the opportunities and constraints involved in the use of a given land area. A geographic information system-based procedure, known as rural settlement suitability evaluation(RSSE) using an improved technique for order preference by similarity to ideal solution(TOPSIS), was adopted to determine the most suitable area for constructing rural settlements in different geographical locations. Given the distribution and independence of rural settlements, a distinctive evaluation criteria system that differed from that of urban suitability was established by considering the level of rural infrastructure services as well as living and working conditions. The unpredictable mutual interference among evaluation factors has been found in practical works. An improved TOPSIS using Mahalanobis distance was applied to solve the unpredictable correlation among the criteria in a suitability evaluation. Uncertainty and sensitivity analyses obtained via Monte Carlo simulation were performed to examine the robustness of the model. Daye, a resource-based city with rapid economic development, unsatisfied rural development, and geological environmental problems caused by mining, was used as a case study. Results indicate the following findings: 1) The RSSE model using the improved TOPSIS can assess the suitability of rural settlements, and the suitability maps generated using the improved TOPSIS have higher information density than those generated using traditional TOPSIS. The robustness of the model is improved, and the uncertainty is reduced in the suitability results. 2) Highly suitable land is mainly distributed in the northeast of the study area, and the majority of which is cultivated land, thereby leading to tremendous pressure on the loss of cultivated land. 3) Lastly, 12.54% of the constructive expansion permitted zone and 8.36% of the constructive expansion conditionally permitted zone are situated in an unsuitable area, which indicates that the general planning of Daye lacks the necessary verification of suitability evaluation. Guidance is provided on the development strategy of rural settlement patches to support decision making in general land use planning. 展开更多
关键词 rural settlement suitability evaluation technique for order preference by similarity to ideal solution mahalanobis distance Daye City
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Effect of Milk Proteins on Physical and Chemical Characteristics of Crispy Puff Snacks
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作者 Ismail Hussein Abd EI-Ghany Mohamed Abdelghany EI-Asser +1 位作者 Khalid Said Nagy Ahmed Ali Abd EI-Maksoud 《Journal of Agricultural Science and Technology(A)》 2013年第8期633-645,共13页
Dairy proteins included sweet whey solids (SWS), whey protein concentrate (WPC), milk protein concentrate (MPC) or sodium caseinate (SC) at level of 10% by weight were extruded with corn, rice, oat flour and o... Dairy proteins included sweet whey solids (SWS), whey protein concentrate (WPC), milk protein concentrate (MPC) or sodium caseinate (SC) at level of 10% by weight were extruded with corn, rice, oat flour and other ingredients in a twin screw extruder. The functional properties and textural of crispy balls snacks (CBS) have been studied. The results showed that different protein types were significantly affected on functional and chemical properties of extrudate. The bulk density of CBS-SC was the lowest due to the highest expansion, while CBS-WPC retained the most water in the product, whereas, the maximum value of water solubility index was obtained in the CBS-CWP. Results also showed that protein digestibility value of extrudates had higher than non-extruded products. Color analysis of CBS-SC and CBS-SWS products had the highest AE values (P ≤ 0.05), whereas CBS-SWS was statistically higher than CBS-SC in rank. Also, it was noticed that CBS-SWS had the highest value of browning index. The hardness of all extrudates products was desirable for expanded crispy where ranged from 17.3 N to 12.18 N. Generally, MPC and SC incorporated with cereal flour had acceptable quality characteristics and improved significantly the functional and texture properties of crispy balls products. 展开更多
关键词 EXTRUSION sodium caseinate whey protein concentrate functional properties crispy product.
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Study on Over-Voltage of 220 kV Transformer's Neutrals and Protection Strategy
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作者 H.P. Yu S.M. Chen +2 位作者 P.C. Yang H. Yin G.L. Wu 《Journal of Energy and Power Engineering》 2011年第11期1102-1108,共7页
In order to limit short-circuit current and satisfy the need of relay setting, only part of the 220 kV power transformer is grounded, so on the neutrals of ungrounded transformers will appear the over-voltage. Current... In order to limit short-circuit current and satisfy the need of relay setting, only part of the 220 kV power transformer is grounded, so on the neutrals of ungrounded transformers will appear the over-voltage. Currently the value of over-voltage on transformer neutral point and the corresponding protection strategy is based on theoretical formula. This article uses the PSCAD/EMTDC software to calculate the over-voltage on the neutral point of 4 ungrounded power transformers in Chongqing 220 kV power grid. The result shows that the power frequency transient over-voltage on the neutrals may reach 178 kV. If the single-phase grounding fault occurs in ungrounded power system, the power frequency over-voltage on the neutrals will be more serious and rise to 138.6 kV. Non-full phase operation may cause serious ferro-resonance over-voltage on the neutrals of no-load transformer, which may last for seconds and may rise to 723.7 kV, causing serious threat to the transformer neutrals and line-side equipment. The article also studies the gap parameter which should be taken on the neutrals of 220 kV transformers at the end. 展开更多
关键词 Neutral point power transformer ARRESTER GAP power frequency over-voltage lightning over-voltage.
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Study on Effect of Age of Seedlings Transplant on the Performance of Tomato (Lycopersicon esculentum) in a Southwestern Nigeria Location
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作者 B. O. Ademiluyi 《Journal of Agricultural Science and Technology》 2011年第3期318-321,共4页
Field trials were conducted at the experimental site of the Department of Plant Science of the University of Ado Ekiti, Nigeria during the 2005 and 2006 cropping season to examine the effects of age of transplanting o... Field trials were conducted at the experimental site of the Department of Plant Science of the University of Ado Ekiti, Nigeria during the 2005 and 2006 cropping season to examine the effects of age of transplanting on the performance of tomato Lycopersieon esculentum L. Establishment count %, plant height stem girth, earliness to flower, and fruit yield were significantly affected by the ages at which the seedlings were transplanted. The 2 and 3 weeks after sowing transplants were identical in performance and gave the highest number of field establishment count, growth increase, and yield. The 4WAS transplants performed better than the 5WAS transplants. It is concluded that a delay in early transplanting of tomato seedlings after 4WAS could lead to a very high reduction in tomato yield in the study area. 展开更多
关键词 TOMATO seedlings age TRANSPLANTING PERFORMANCE yield.
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Statistical study on the suprathermal electrons properties around dipolarization fronts in Earth's magnetotail 被引量:4
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作者 WANG Yue ZHOU Meng DENG XiaoHua 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2015年第6期961-966,共6页
In order to investigate the suprathermal electron flux(>30 ke V) around dipolarization fronts(DFs), we statistically studied the suprathermal electron flux variations and pitch angle distributions of hundreds of ea... In order to investigate the suprathermal electron flux(>30 ke V) around dipolarization fronts(DFs), we statistically studied the suprathermal electron flux variations and pitch angle distributions of hundreds of earthward propagating DFs observed by THEMIS spacecraft during its tail seasons in years 2008–2009. We focused on the electron flux variations across DFs and electron anisotropies behind DFs. We divided DF into three sectors in the equatorial plane: Dusk, central and dawn sectors. The sectors are defined according to the DF normals with respect to DF's meridian in the equatorial plane(the symmetric line of DF). We found that events with electron flux increases and decreases behind the fronts had no particular dependence on the observation locations. In addition, there was no obvious dependence of electron anisotropy behind DF on the different sectors of DF. 展开更多
关键词 suprathermal electrons dipolarization front (DF) pitch angle distribution
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