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区域金融产业成长的时序特征研究——以西安为例
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作者 殷仲民 秦华丽 王宇娟 《开发研究》 CSSCI 2008年第1期133-136,共4页
金融产业成长表现为时间上不间断的连续过程,经历由低级阶段到高级阶段的推进,逐渐实现量性区间向质性区间的过渡。本文从量性指标和质性指标两方面,通过纵(时间序列)、横(空间维度)两个方向的对比,考察西安区域金融产业成长的基本现状... 金融产业成长表现为时间上不间断的连续过程,经历由低级阶段到高级阶段的推进,逐渐实现量性区间向质性区间的过渡。本文从量性指标和质性指标两方面,通过纵(时间序列)、横(空间维度)两个方向的对比,考察西安区域金融产业成长的基本现状,研究西安市金融产业成长的时序特征,希望对加快西安金融产业成长有一定的意义。 展开更多
关键词 区域金融 金融产业成长 量性指标 指标
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青岛市金融成长的实证分析及对策研究
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作者 徐胜 欧阳修顺 《中国证券期货》 2009年第12X期33-37,共5页
本文从金融规模、结构和效率等方面建立了区域金融成长评测指标体系,对青岛金融成长状况进行了全面详尽的分析,并与全国其他四个计划单列城市:深圳、宁波、厦门、大连进行了横向的比较分析。然后从鼓励金融创新、促进区域民间融资发展... 本文从金融规模、结构和效率等方面建立了区域金融成长评测指标体系,对青岛金融成长状况进行了全面详尽的分析,并与全国其他四个计划单列城市:深圳、宁波、厦门、大连进行了横向的比较分析。然后从鼓励金融创新、促进区域民间融资发展、大力发展金融市场、构筑大金融组织体系、立足城市特色发展物流金融等方面就青岛在促进金融成长方面提出了一些具体的措施。 展开更多
关键词 量性指标分析 结构指标分析 效率指标分析
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Selection of Example Varieties Used in the DUS Test Guideline of Tagetes L. 被引量:1
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作者 刘艳芳 张建华 +6 位作者 王烨 陈海荣 徐云 杨晓洪 张惠 管俊娇 王江民 《Agricultural Science & Technology》 CAS 2012年第10期2110-2111,2116,共3页
[Objective] Taking the characteristic of flower diameter of Tagetes L.as an example,this study aimed to select example varieties used in the DUS Test Guideline of Tagetes L.[Method] Two continuous years of measurement... [Objective] Taking the characteristic of flower diameter of Tagetes L.as an example,this study aimed to select example varieties used in the DUS Test Guideline of Tagetes L.[Method] Two continuous years of measurements of flower diameter of 25 varieties were collected and then analyzed by using the box plot to illustrate the uniformity and stability of flower diameter of each variety.[Result] According to the information of variability,distribution symmetry of measurements and outliers of flower diameter of varieties provided by box plots,variety 16,2 and 4 were selected as the example varieties for the three expression states with respective flower diameter of 3.0-4.4,6.0-7.4 and 9.0-10.4 cm.[Conclusion] The box plot is an efficient method for the general analysis of varieties,which provides information covering the actual and possible expression range,median and outliers of measurements of flower diameter of each variety.It also provides references for selecting example varieties for other quantitative characteristics and evaluating the quality of varieties. 展开更多
关键词 DUS Test Guideline of Tagetes L. Quantitative characteristic Example variety The box plot
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Effects of Nitrogen Fertilizer Management on Biological Traits and Physiological Indexes at Seedling Stage and Yield of Directly-sown Rapeseed(Brassica napus L.) 被引量:1
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作者 杨云飞 刘士山 吴永成 《Agricultural Science & Technology》 CAS 2017年第12期2401-2405,2414,共6页
Field experiments were carried out to study the effects of different nitroge- napplication rates and application times on biological traits and physiological indexes of directly-sown rapeseed (Brassica napus L.) at ... Field experiments were carried out to study the effects of different nitroge- napplication rates and application times on biological traits and physiological indexes of directly-sown rapeseed (Brassica napus L.) at the seedling stage and investigate the relationship between these biological traits or physiological indexes at the seedling stage and yield, so as to provide scientific theoretical support for high yield and efficient fertilization management in production of winter rapeseed. Field trials were conducted in Chengdu plain of Sichuan Province under rice-rapeseed rotation system during the period of 2011-2012. The nitrogen application rate trial consisted of five nitrogen levels (0, 90, 180, 270 and 360 kg/hm2) and the nitrogen application time trial included NTl(single application as base fertilized), NT2 (bottom application +one time of topdressing at seedling stage) and NT3 (bottom application+two times of topdressing at seedling stage) under the same nitrogen rate (225 kg/hm2). The results indicated that compared with no nitrogen application (NO) treatment, the in- crease of nitrogen fertilizer is beneficial to the increase of biological traits including plant height, green leaf number, leaf area index and dry weight of rapeseed at the seedling stage, the improvement of physiological indexes including total nitrogen content, chlorophyll content and soluble protein content of functional leaves, and the reduction of soluble sugar content. Nitrogen rate was linearly correlated with various biological traits at the seedling stage and physiological indexes including total nitro- gen content, chlorophyll content and soluble sugar content in functional leaves over- a/I, but in parabolic correlation with soluble protein content. Under the same nitrogen rate, NT2 treatment exhibited biological traits remarkably or significantly higher than NT1 treatment and NT3 treatment. The nitrogen application times were linearly cor- related with the physiological indexes of functional leaves at the seedling stage. The various biological traits and physiological index of functional leaves at the seedlings stage were in quadratic function parabolic correlation with seed yield, and the corre- lation was significant (P〈0.05). Therefore, under the rice-rapeseed rotation system in Chengdu plain, the economic rational nitrogen rate is 180-225 kg/hm2, and the mode of bottom application + one time of topdressing (NT2) is suitable. 展开更多
关键词 Winter rapeseed (Brassica napus L.) Direct seeding Nitrogen fertilizermanaaement Bioloqical traits Physioloqical index YIELD
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Full tensor gravity gradiometry data inversion:Performance analysis of parallel computing algorithms 被引量:2
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作者 侯振隆 魏晓辉 +1 位作者 黄大年 孙煦 《Applied Geophysics》 SCIE CSCD 2015年第3期292-302,465,共12页
We apply reweighted inversion focusing to full tensor gravity gradiometry data using message-passing interface (MPI) and compute unified device architecture (CUDA) parallel computing algorithms, and then combine M... We apply reweighted inversion focusing to full tensor gravity gradiometry data using message-passing interface (MPI) and compute unified device architecture (CUDA) parallel computing algorithms, and then combine MPI with CUDA to formulate a hybrid algorithm. Parallel computing performance metrics are introduced to analyze and compare the performance of the algorithms. We summarize the rules for the performance evaluation of parallel algorithms. We use model and real data from the Vinton salt dome to test the algorithms. We find good match between model efficiency and feasibility of parallel computing gravity gradiometry data. and real density data, and verify the high algorithms in the inversion of full tensor 展开更多
关键词 MPI CUDA performance metrics full tensor gravity gradiometry density inversion
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A new method of characterizing equivalent strain for equal channel angular processing 被引量:1
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作者 赵军 王振华 +3 位作者 孙淑华 赵德利 任利国 傅万堂 《Journal of Central South University》 SCIE EI CAS 2009年第3期349-353,共5页
In order to establish the quantitative relationship between equivalent strain and the performance index of the deformed material within the range of certain passes for equal channel angular processing (ECAP), a new ... In order to establish the quantitative relationship between equivalent strain and the performance index of the deformed material within the range of certain passes for equal channel angular processing (ECAP), a new approach to characterize the equivalent strain was proposed. The results show that there exists better accordance between mechanical property (such as hardness or strength) and equivalent strain after rolling and ECAP in a certain range of deformation amount, and Gauss equation can be satisfied among the equivalent strain and the mechanical properties for ECAP. Through regression analysis on the data of hardness and strength after the deformation, a more generalized expression of equivalent strain for ECAP is proposed as:ε=k0exp[-(k1M-k2)^2], where M is the strength or hardness of the material, k1 is the modified coefficient (k1∈ (0, 1)), ko and k2 are two parameters dependent on the critical strain and mechanical property that reaches saturation state for the material, respectively. In this expression the equivalent strain for ECAP is characterized novelly through the mechanical parameter relating to material property rather than the classical geometry equation. 展开更多
关键词 equal channel angular processing (ECAP) equivalent strain mechanical property characterizing method
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Radial Non-uniformity Index Research on High-density,High-flux CFB Riser with Stratified Injection 被引量:3
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作者 Geng Qiang Wang Lu +3 位作者 Li Zhichao Li Chunyi Liu Yibin You Xinghua 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2012年第4期64-72,共9页
A high-density, high-flux circulating fluidized bed (CFB) riser (100 mm in ID and 10.614 m in height) was ap- plied in a wide range of operating conditions (with solid fluxes up to 400 kg/m2s and superficial gas ... A high-density, high-flux circulating fluidized bed (CFB) riser (100 mm in ID and 10.614 m in height) was ap- plied in a wide range of operating conditions (with solid fluxes up to 400 kg/m2s and superficial gas velocities up to 12 m/s) to examine its radial non-uniformity dynamics. The solids holdup was determined through the use of a fiber-optic probe at 11 axial levels. The results indicated that under all operating conditions, the high superficial gas velocity and low solid flux- es maintained a low radial non-uniformity index (RNI). The high-density/flux CFB riser had several unique characteristics, so that the peak of the radial solids holdup profile occurred at a position with r/R=0.8. The RNI and solids holdup at the cross-sectional position had a good logarithmic relationship at the low-density condition (with a mean solids holdup of 〈0.2), and the RNI decreased when the mean solids holdup exceeded 0.2. Investigation of the dynamics of stratified injec- tion revealed that the feed ratio had an important effect on G, and on solids holdup distribution. A novel "〈" shaped axial solids holdup profile was found. Gs decreased sharply when the up-flow feed ratio exceeded 0.5, and RNI was lowest when the up-flow feed ratio was 1. 展开更多
关键词 fluidization high density/flux CFB riser radial non-uniformity index stratified injection feed ratio
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Numerical simulation study on the thermal environment in heading face 被引量:4
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作者 ZHAO Fu-jun HUANG Shou-yuan +1 位作者 SHEN Pei-wen LI Yan-bo 《Journal of Coal Science & Engineering(China)》 2010年第3期272-276,共5页
Based on κ-ε turbulence model, the distributions of the velocity field, tempera- ture field, thermal comfort index, PMV-PPD (Predicted Mean Vote-Predicted Percentage Dissatisfied), and air quality index, mean age ... Based on κ-ε turbulence model, the distributions of the velocity field, tempera- ture field, thermal comfort index, PMV-PPD (Predicted Mean Vote-Predicted Percentage Dissatisfied), and air quality index, mean age of air were obtained of Zhouyuanshan Coal Mine in -650 m level of a heading face by CFD(Computational Fluid Dynamics)software, Airpak 2.0. Moreover, the human thermal comfort and the air quality of the heading face were analyzed with PMV-PPD and mean age of air indices, which received an intuitive visualization and accurate evaluation results. In order to create a safe, comfortable, and economical underground operating environment, a scientific, rational, and comprehensive prediction and evaluation needed to provide a theoretical and technical basis for coal mine ventilation, cooling, heat harm treatment, and prevention. Meanwhile, from the human thermal comfort and air quality to research the underground environment, it embodied the concept of being human oriented. 展开更多
关键词 thermal environment heading face thermal comfort predicted mean vote- predicted percentage dissatisfied indices mean age of air
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Attitude control allocation strategy of high altitude airship based on synthetic performance optimization 被引量:1
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作者 遆晓光 韩放 姚郁 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第6期746-750,共5页
This paper presents a method for solving the attitude control problem of high altitude airship (HAA) with aerodynamic fin and vectored thruster control. The algorithm is based on the synthetic optimization of dynamic ... This paper presents a method for solving the attitude control problem of high altitude airship (HAA) with aerodynamic fin and vectored thruster control. The algorithm is based on the synthetic optimization of dynamic performance and energy consumption of airship. Firstly, according to the system overall configuration, the dynamic model of HAA was established and the HAA linearized model of longitudinal plane motion was obtained. Secondly, using the classic PID control theory, the HAA attitude control system was designed. Thirdly, through analyzing the dynamic performance of airship with fin or vectored thruster control, the synthetic performance index function with different weighting functions was determined. By means of optimizing the obtained performance index function, the attitude control of high altitude airship with good dynamic performance and low energy consumption was achieved. Finally, attitude control allocation strategy was designed for the airship station keeping at an altitude of 22 km. The simulation experiment proved the validity of the proposed algorithm. 展开更多
关键词 high altitude airship attitude control synthetic performance optimization control strategy
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State of the art of impact testers for spot welds 被引量:1
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作者 Hua Fu' an Ma Mingtu +1 位作者 Li Jianping Wang Guodong 《Engineering Sciences》 EI 2014年第5期59-66,共8页
Impact testing is a primary method to evaluate the impact property of resistance spot welding,which is an important quality index in automotive industry.For testing impact properties of spot welds,many customized test... Impact testing is a primary method to evaluate the impact property of resistance spot welding,which is an important quality index in automotive industry.For testing impact properties of spot welds,many customized testers have been developed.This paper summarized some of the impact testers reported in open literatures and the emphasis was placed on the equipment structures,functions,technical parameters,advantages and disadvantage,etc.Some key issues about the development of the testers such as kinematic energy input mode,fixture design,combined load testing,sensor and data acquisition were discussed.Finally,the problems and prospects in the research and development of impact testers for spot welds were pointed out. 展开更多
关键词 resistance spot welding impact testing impact tester impact strength
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Evaluation of Soil Quality Indicators in Sugarcane Management in Sandy Loam Soil 被引量:5
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作者 S.A.C.SANT'ANNA M.F.FERNANDES +1 位作者 W.M.P.M.IVO J.L.S.COSTA 《Pedosphere》 SCIE CAS CSCD 2009年第3期312-322,共11页
An important factor for the sustainability of soils highly susceptible to degradation is the use of monitoring tools that promptly and realistically reflect changes imposed on soil by different cropping systems. To se... An important factor for the sustainability of soils highly susceptible to degradation is the use of monitoring tools that promptly and realistically reflect changes imposed on soil by different cropping systems. To select soil quality indicator variables in sugarcane (Saccharum officinarum L.) production areas that fulfill the criteria of sensitivity to management practices and between-season consistency in the management discrimination, ten composite soil samples (0–10 cm) were collected in July 2005 (rainy season) and again in March 2006 (dry season) from areas under cultivation of organic sugarcane (OS), green sugarcane (GS), burned sugarcane (BS) and from an adjacent native forest (NF) area at Usina Triunfo, Boca da Mata, Alagoas, Brazil. Microbial biomass-C (MBC), total organic C (TOC), soil enzyme activity expressed as the rate of fluorescein diacetate (FDA) hydrolysis, mean weight diameter of water-stable soil aggregates (MWD), and percentage of water-stable macroaggregates (PWSA) were analyzed. Although MBC and TOC were higher in NF than in the cultivated areas, no differences were observed in these C pools between the three sugarcane systems. The response of FDA to the site management was dependent on the sampling time. In the rainy period, the activity followed the order: NF > OS > GS > BS, whereas in the dry season, only NF differed from the other treatments. Irrespective of the sampling time, MWD and PWSA decreased in the order NF > OS = GS > BS. The variables MWD and PWSA are quite sensitive for discriminating between site management histories regardless the sampling season. 展开更多
关键词 fiuorescein diacetate green-sugarcane organic matter management sugarcane (Saccharum oJficinarum L.) sustainable agricultural use
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Micromorphological Evidences of Climatic Change in Yazd Region,Iran 被引量:2
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作者 Ruhollah Taghizadeh Mehrjardi Shahla Mahmoodi +1 位作者 Ahmad Heidari Ali Akbarzadeh 《Journal of Mountain Science》 SCIE CSCD 2009年第2期162-172,共11页
The fact of, present is the key of the past, will help us to use paleosols properties as indicators of the ecological characteristics of past .time, particularly the paleoclimate. In this respect the micro- morphologi... The fact of, present is the key of the past, will help us to use paleosols properties as indicators of the ecological characteristics of past .time, particularly the paleoclimate. In this respect the micro- morphological properties showed to be a very good indicator. Therefore, for investigating of climate change in Ardakan-Yazd plain, Central Iran 9 pedons were digged and described. Yazd has an arid climate with less than 100 mm annual precipitation and more than 22℃ mean annual temperature (Aridic-hyper thermic soil moisture and temperature regions, respectively). Based on the morphological and physicochemical analysis Arglic, Calcic and Gypsic diagnostic horizons have been distinguished in these soils. Thin section studied showed that the illuviated form of clay includes, infillings on channel, coating on pendant, on nodules and on grains, at lower depths and also juxtaposed calcite needles on void argillan at upper part of the profiles. Mineralogical result showed fine clay in arglic horizon, too. Considering depth and forms of these pedofeatures, we concluded that, the observed illuviated clays at lower depth must be the result of the more humid climate of the past, where the carbonates have been removed completely as pendant, nodules or coating to considerable depth, following processes, clay has been dispersed and also trans located to these depths. In contrast to these features, the juxtaposed needle calcite at the shallower depth is probably the result of drier climate of today. 展开更多
关键词 Micromorphologieal indicators CLIMATECHANGE Arglic horizon Yazd region
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A Routing Metric Based on Available Bandwidth Routing in Wireless Mesh Networks
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作者 Ji-soo LEE Jun-ho HWANG Myung-sik YOO 《Journal of Measurement Science and Instrumentation》 CAS 2011年第3期264-267,共4页
Wireless Mesh Network has drawn much attention due to wide area service coverage with low system cost and being easy to install.However,WMN suffers from high bit error rate,which provides different link capacity among... Wireless Mesh Network has drawn much attention due to wide area service coverage with low system cost and being easy to install.However,WMN suffers from high bit error rate,which provides different link capacity among wireless mesh routers.The conventional routing metrics select the path based on link quality.The link with the best quality is preferred as the data transmission path,and thus all nodes likely select the same link,which leads to network performance degradation.This paper proposes a routing metric that considers the available bandwidth and the number of nodes suffering congestion in the path.It is confirmed that the proposed method provides higher network performance of reduced delay,reduced packet loss and increased throughput than conventional routing metrics. 展开更多
关键词 routing metric overload aware available bandwidth MULTI-CHANNEL wireless mesh network
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Exploring Enterprise Performance Indicators Network: A Case Study of China Telecommunication Industry 被引量:1
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作者 Shi Wenhua Du Yu Zhang Xiaohang 《China Communications》 SCIE CSCD 2012年第12期153-163,共11页
Perforrmnce indicators play some important roles in enterprise operation. Both researchers and managers have recently pointed out that the identification of correlation between different performmance indicators may le... Perforrmnce indicators play some important roles in enterprise operation. Both researchers and managers have recently pointed out that the identification of correlation between different performmance indicators may lead to a better understanding of business. However, it is becoming more and more difficult to measure and analyze these indicators since the fast growing number of performance indicators and the complex relationships between them The existing categories failed to reflect these changes in an adequate way, and the quantitative analysis methods for identifying the characters of those pefformance indicators are still worthy of investigation. The main objective of this paper is to propose a practical methodology for managing and analyzing performance indicators in enterprises, which focuses on building up a performance indicator system and discovering the characters of those performance indicators by applying complex network methods. The empirical results of a telecommunieation enterprise show that the proposed method can be effective in understanding the correlations between performance indicators. 展开更多
关键词 performance indicator complex networks telecommunication industry
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Preservation of Linear Constraints in Approximation of Tensors
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作者 Eugene Tyrtyshnikov 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2009年第4期421-426,共6页
For an arbitrary tensor(multi-index array) with linear constraints at each direction,it is proved that the factors of any minimal canonical tensor approximation to this tensor satisfy the same linear constraints for t... For an arbitrary tensor(multi-index array) with linear constraints at each direction,it is proved that the factors of any minimal canonical tensor approximation to this tensor satisfy the same linear constraints for the corresponding directions. 展开更多
关键词 Multi-index arrays TENSORS linear constraints low rank approximation canonicaltensor decomposition multilevel matrices.
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Allium sativum Flavor Compounds as an Indicator for Garlic Identity and Quality Determination 被引量:1
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作者 Ruta Galoburda Karina Bodniece Thierry Talou 《Journal of Food Science and Engineering》 2013年第5期226-234,共9页
The objective of the study was to research the aroma profile of volatile compounds in garlic subspecies originating from Latvia, and compare them with the aroma composition of garlic grown in the region of Midi-Pyrene... The objective of the study was to research the aroma profile of volatile compounds in garlic subspecies originating from Latvia, and compare them with the aroma composition of garlic grown in the region of Midi-Pyrenees (France). It was established that hard-neck garlic tends to contain more diallyl disulfide (DADS), the main decomposition product of allicin. Compared to the hard-neck subspecies, the content of allyl mercaptan, one of the major compounds producing the strong odor detectable after ingestion of garlic, was significantly lower in the soft-neck garlic clones. The amount of cyclic compound 3-vinyl-1,2-dithiin differed considerably with higher contents in the soft-neck subspecies. The results also demonstrate the soft-neck garlic as a more suitable subspecies for long-term storage. In general, the results show no significant difference in the content of DADS and the total content of other flavor compounds between hard-neck and soft-neck garlic grown in the region of Midi-Pyrenees and Latvia. However, comparing garlic subspecies originating from France and Latvia by the content of allyl mercaptan, 1,2-dithiolane and 3-vinyl-1,2-dithiin, a considerable proportional difference of these volatiles was determined. Also, a significant difference was established in the content of DADS between the white garlic variety "Blanc de Lomagne" (France, region of Midi-Pyrenees) and white garlic grown in other countries. The results of this study suggest the suitability of solid phase microextraction (SPME) and gas chromatography (GC) methods for quality control of garlic originating from France. 展开更多
关键词 Allium sativum diallyl disulfide FLAVOR GARLIC IDENTITY
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Vulnerability to Desertification in Lebanon Based on Geo-information and Socioeconomic Conditions
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作者 Talal Darwish Pandi Zdruli +3 位作者 Ramy Saliba Mohamad Awad Amin Shaban Ghaleb Faour 《Journal of Environmental Science and Engineering(B)》 2012年第7期851-864,共14页
Desertification caused by land degradation and overexploitation of natural resources is threatening large parts of eastern and southern Mediterranean. The actual state of desertification sensitivity in Lebanon was spa... Desertification caused by land degradation and overexploitation of natural resources is threatening large parts of eastern and southern Mediterranean. The actual state of desertification sensitivity in Lebanon was spatially assessed using site specific environmental bio-physical indicators, demographic pressure and socioeconomic conditions. Bio-physical assessment included the aridity index derived from integrated assessment of the historical data for 48 climatic stations spread throughout the country, the new detailed soil map at 1:50,000 scale, and the updated land cover/use map at 1:20,000 derived from IKONOS 2005. The methodology also included livelihood conditions and poverty at local administrative "Caza" level. Results showed the integrated impact of local climate, soil and vegetation quality and socioeconomic conditions on sensitivity to desertification. A total of 78% of the territories have low and very low climate quality index preconditioning the sensitivity to desertification. Fourteen Cazas out of 26 in total, representing more than 66% of the country, have low socioeconomic satisfaction index. Furthermore, negative trends are alleviated by good quality relict soils and vegetation cover. The actual extent of desertification covers 40.48% of the national territory, much of which occurs under semi-arid climate, moderate or low soil and vegetation quality and poor living conditions. The outcome of this research adjusted the previous coarse estimates of desertification prone areas at the national level. Results allow for realistic, policy oriented local assessment for responsive land use planning and proactive sustainable, national and local land management in the context of the national action plan to combat desertification. 展开更多
关键词 Integrated assessment land degradation east Mediterranean sensitivity sustainable land management.
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Degradation of Wetlands on the Qinghai-Tibet Plateau:A Comparison of the Effectiveness of Three Indicators 被引量:15
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作者 GAO Jay LI Xi-lai +1 位作者 CHEUNG Alan YANG Yuan-wu 《Journal of Mountain Science》 SCIE CSCD 2013年第4期658-667,共10页
The Qinghai-Tibet Plateau encompasses a large quantity of wetlands, some of which have been degraded to varying severity levels. In the literature, a number of degradation indicators have been proposed to evaluate eco... The Qinghai-Tibet Plateau encompasses a large quantity of wetlands, some of which have been degraded to varying severity levels. In the literature, a number of degradation indicators have been proposed to evaluate ecological health of wetlands, but their effectiveness in the plateau environment remains unknown. In this study, we assessed the effectiveness of three degradation indicators, soil moisture content at lo em deep, vegetative cover, and density of pika burrows. The degradation severity of wetlands in Maduo County on the Qinghai-Tibet Plateau is enumerated at four levels, intact, slight, moderate and severe. Analysis of xo6 samples collected in the field demonstrates that the density of pika burrows is the least reliable indicator. By comparison, vegetative cover and underlying soil moisture content are more reliable, even though neither is a perfect indicator as the difference among adjacent levels of severity as revealed by t-test is not always statistically significant. The imperfection of vegetative cover as an indicator is due to its variation among different types of wetlands. The limitation of moisture content is attributed to its non-linear relationship with wetland degradation. Above the threshold of about 50% in moisture content wetlands are unlikely to be degraded. It is recommended that moisture be measured at the point near the surface and vegetative cover be further differentiated by species in order to improve their effectiveness. 展开更多
关键词 Wetland degradation Grass cover Soilmoisture Pika damage Qinghai-Tibet Plateau
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Long Term Assessment of a Grid Connected Solar PV System in Sydney 被引量:2
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作者 Saad Odeh 《Journal of Energy and Power Engineering》 2016年第10期591-599,共9页
This paper assesses 4 years of operation of a 1.75 kW roof top solar PV system installed in a Sydney suburban house. The system consists of 10 PV panels, a DC/AC inverter, and a grid connected gross meter. Solar elect... This paper assesses 4 years of operation of a 1.75 kW roof top solar PV system installed in a Sydney suburban house. The system consists of 10 PV panels, a DC/AC inverter, and a grid connected gross meter. Solar electricity delivered to grid is verified with the results from a computer simulation package (PVSYST) by adopting the installed component specifications, operation conditions, and weather data of the site. The results show high consistency between the values of energy delivered to the grid measured by the energy company and the energy estimated by system simulation. New system performance indicator is developed and called the optimum performance compliance ratio (PCR). It is a measure of the compliance of the output of the designed PV system with the output which would be produced by the same system with a solar tracker. This indicator provides system designers, contractors and energy providers with the actual capacity of the system that they can offer the end-users. 展开更多
关键词 Long term assessment grid connected PV system solar electricity performance indicator.
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Measuring IP Performance Metrics on Mobile Network with Heterogeneous Wireless Technologies
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作者 Pyung-soo KIM Jeong-hun CHOI 《Journal of Measurement Science and Instrumentation》 CAS 2010年第3期289-292,共4页
The new measurement scheme of IP performance metrics is for the mobile network in heterogeneous wireless network environment. In the proposed scheme, when Mobile Nodes (MNs) inside the mobile network needs to under... The new measurement scheme of IP performance metrics is for the mobile network in heterogeneous wireless network environment. In the proposed scheme, when Mobile Nodes (MNs) inside the mobile network needs to understand the condition of multiple comrmunicatinn paths outside the mobile netwtrk, they can get IP performance metrics, such as delay, jitter, bandwidth, packet loss, etc., irrespective of the preserre or absence of measurement functionality. At the same time, the proposed scheme dees not require the MN to he involved in measuring IP performance metrice. The Multihomed Mobile Router (MMR) with heterogeneons wireless interfaces measures IP performance metrics on behalf of the MNs inside the mobile network. Then, MNs can get measured IP perfonmnce metries from the MMR using L3 messages. The proposed scheme can reduce burden and power consumption of MNs with limited resource and batty power since MNs don' t measure IP performance metrics directly. In addition, it can reduce considerably traffic overhead over wireless links on multiple measurement paths since signaling messages and injeeted testing traffic are reduced. 展开更多
关键词 performance metrics network mobility HETEROGENEOUS
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