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基于CMMI的组织过程资产库的开发与应用 被引量:4
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作者 任爱华 张明晶 罗晓峰 《计算机工程与设计》 CSCD 北大核心 2008年第15期3936-3940,共5页
CMMI模型提供了产品开发过程的最佳实践,如何有效地建立基于CMMI的组织过程资产库是企业实施CMMI中最佳实践的基础,充分地利用组织过程资产库是有效地实施这些最佳实践的保障。从资产库的开发到资产库的应用的角度,阐述了资产库的重要... CMMI模型提供了产品开发过程的最佳实践,如何有效地建立基于CMMI的组织过程资产库是企业实施CMMI中最佳实践的基础,充分地利用组织过程资产库是有效地实施这些最佳实践的保障。从资产库的开发到资产库的应用的角度,阐述了资产库的重要意义和作用,提出并研制了支持组织过程资产库建立的工具,并总结了实施CMMI过程的经验和方法。 展开更多
关键词 能力成熟度模型集成 组织过程资产 能力成熟度模型集成的实施 标准过程 生命周期模型 裁剪指南 度量库
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基于目标驱动与活动相结合软件度量模型的改进研究 被引量:1
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作者 蒋依欣 叶柏龙 邓军 《计算机工程与设计》 CSCD 北大核心 2009年第11期2619-2621,2625,共4页
根据已有的目标驱动与活动相结合的度量模型GIAM-D,进行了进一步的完善与扩展形成EGIAM-D模型。分析了现有GIAM-D的缺点进行了相关的改进研究,主要建立了EGIAM-D的统一度量标识库,通过对度量各集定义的精简和合并方便了整个度量过程的... 根据已有的目标驱动与活动相结合的度量模型GIAM-D,进行了进一步的完善与扩展形成EGIAM-D模型。分析了现有GIAM-D的缺点进行了相关的改进研究,主要建立了EGIAM-D的统一度量标识库,通过对度量各集定义的精简和合并方便了整个度量过程的半自动化,并给出了研究的相应算法,从而大大提高了度量模型的实用性。 展开更多
关键词 软件过程度量 度量模型 度量标识定义 度量半自动化 过程改进
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基于目标驱动与活动的软件过程度量模型的改进
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作者 蒋依欣 叶柏龙 邓军 《现代计算机》 2008年第10期129-132,共4页
根据已有的目标驱动与活动相结合的度量模型GIAM-D,进行了进一步完善扩展形成EGIAM-D模型,建立EGIAM-D的统一度量标识库,通过对度量各集定义的精简和合并达到整个度量过程的半自动化,并给出相应的算法。
关键词 软件过程度量 度量标识定义 度量半自动化
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Effects of Planting Density on Yield and Sourcesink Characteristics of Sweet Potato[Ipomoea batatas(L.) Lam] 被引量:6
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作者 张海燕 解备涛 +6 位作者 汪宝卿 王庆美 董顺旭 李爱贤 侯夫云 段文学 张立明 《Agricultural Science & Technology》 CAS 2015年第8期1628-1633,1642,共7页
[Objective] The aim was to resolve the issue of sparsely planting (37 500-40 500 plants/hm2) of sweet potato in hilly areas. [Method] The starch-oriented Jishu No.21 and raw-eating oriented Jishu No.22 were studied ... [Objective] The aim was to resolve the issue of sparsely planting (37 500-40 500 plants/hm2) of sweet potato in hilly areas. [Method] The starch-oriented Jishu No.21 and raw-eating oriented Jishu No.22 were studied to explore effects of planting density on yield and sink and source characteristics of sweet potato. [IRe- suit] Leaf area index of Jishu No.21 and Jishu No.22 were increasing upon planting density. Leaf area index of the same planting density showed a single-peak curve. Specifically, leaf area index grew fast during the 40th-80th d after planting, and reached the peak on the 80th d after planting, followed by decreasing. What's more, ventilation and sunshine transmission both declined upon planting density, as well as the number of leaf, the number of branch, the length of vine, dry and fresh weights of stem and leaf. When planting density exceeded 75 000 plants/hm2, the yield of sweet potato dropped dramatically. Besides, the optimal planting density tended to be volatile upon cultivars. For example, the range of 45 000-60 000 plants/hm2 is the optimal planting density of Jishu No.21 and the range of 60 000-75 000 plants/hm2 is the optimal planting density of Jishu No.22. [Conclusion] It can be concluded that rational planting densities would well coordinate sweet potato growth of ground parts and underground parts to get a high yield by providing a rational group structure. Considering the optimal planting density differs upon cultivars, it is necessary to take genotype, environment, soil fertility and planting density into consideration in determining planting density. 展开更多
关键词 Sweet potato Planting density YIELD Source-sink characteristics
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Carbon pool structure and carbon density of soil in Pinus koraiensis plantation ecosystem 被引量:4
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作者 丁壮 张彦东 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第2期177-182,I0005,共7页
The organic carbon contents,carbon density and carbon storage of the soil in the Pinus koraiensis plantation ecosystem were investigated in Maoershan experimental forest farm,Shangzhi County,Heilongjiang,on the west s... The organic carbon contents,carbon density and carbon storage of the soil in the Pinus koraiensis plantation ecosystem were investigated in Maoershan experimental forest farm,Shangzhi County,Heilongjiang,on the west slope of the Zhangguangcai Mountains in northeastern China for providing data to evaluation of the carbon balance in forest ecosystem of northeastern China.These soil carbon indicators were measured in three forest types,pure P.koraiensis plantation,P.koraiensis and Betula platyphylla mixed forest,and the P.koraiensis and Quercus mongolica mixed forest.The soil carbon pool consisted of four compartments,namely L layer,F layer,H layer and B layer.With variance analysis,we found that both organic carbon content and carbon density of the soil were significantly affected by forest types,soil compartments and slope positions.The highest soil carbon density(278.63 Mg·ha^-1).was observed in the mixed forest of P.koraiensis and Q.mongolica.The B layer had the highest carbon density(212.28 Mg·ha^-1) among all the soil compartments.In terms of slope position,the highest soil carbon density(394.18 Mg·ha^-1) presented in the low slope.Besides,soil carbon content and carbon density had a marked change with the organic matter content and vertical depth of the soil in each compartment.The results of this study implied that in the temperate humid region,the mixed ecosystem of regional Pinus koraiensis plantations and natural forest had relatively high carbon storage capability. 展开更多
关键词 soil carbon pool soil carbon density soil carbon content Pinus koraiensis plantation ecosystem mixed forest
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Evapotranspiration and humidity variations in response to land cover conversions in the Three Gorges Reservoir Region 被引量:3
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作者 DENG Hua SHAO Jing-an 《Journal of Mountain Science》 SCIE CSCD 2018年第3期590-605,共16页
A new land cover classification system was established for the Three Gorges Reservoir Region(TGRR) after considering the continuity of inundation and the natural characteristics of land cover. The potential evapotrans... A new land cover classification system was established for the Three Gorges Reservoir Region(TGRR) after considering the continuity of inundation and the natural characteristics of land cover. The potential evapotranspiration(PET) was predicted using a modified Penman-Monteith(P-M) model. The region's ratio of precipitation to evapotranspiration was calculated as the humidity index(HI). The data obtained was used to analyze climatic responses to land cover conversions from the perspectives of evapotranspiration and humidity variations. The results show that, from 1997 to 2009, the average annual PET increased in the early years and decreased later. In terms of overall spatial distribution, a significant reciprocal relationship appeared between annual PET and annual HI. In 1997,the annual PET was higher in the lower reaches than in the upper reaches of the TGRR, but the areas with high PET shifted substantially westward by 2003. The annual PET continued to increase in 2006, but the areas with high PET shrank by 2009. In contrast, the annual HI showed varying degrees of localized spatial variability. Over the three periods, the dominantforms of land cover conversions occurred from evergreen cover to seasonal green cover, from seasonal green cover to evergreen cover, and from seasonal green cover to seasonally inundated areas, respectively. These accounted for 48.0%, 38.4%, and 23.8% of the total areas of converted land covers in the three periods, respectively. During the period between 1997 and 2003, the main forms of land cover conversions resulted in both positive and negative growths in the average annual PET, while all of them pushed down the average annual HI. From 2003 to 2006, the reservoir region experienced neither a decrease in the annual PET nor an increase in the annual HI. The period between 2006 and 2009 saw a consistent downward trend in the annual PET and a consistent upward trend in the annual HI. 展开更多
关键词 Land cover EVAPOTRANSPIRATION Humidity variations RESPONSE Three Gorges Reservoir Region
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Temperature Effects of Parabolic Linear Bound Potential and Coulomb Bound Potential Quantum Dot Qubit 被引量:2
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作者 CHEN Ying-Jie XIAO Jing-Lin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第10期601-605,共5页
On the condition of electric-LO phonon strong coupling in a parabolic quantum dot,we obtain theeigenenergy and the eigenfunctions of the ground state and the first-excited state using the variational method ofPekar ty... On the condition of electric-LO phonon strong coupling in a parabolic quantum dot,we obtain theeigenenergy and the eigenfunctions of the ground state and the first-excited state using the variational method ofPekar type.This system in a quantum dot may be employed as a two-level quantum system-qubit.When the electronis in the superposition state of the ground state and the first-excited state,we obtain the time evolution of the electrondensity.The relations of the probability density of electron on the temperature and the electron-LO-phonon couplingconstant and the relations of the period of oscillation on the temperature,the electron-LO-phonon coupling constant,the Coulomb binding parameter and the confinement length are derived.The results show that the probability densityof electron oscillates with a period when the electron is in the superposition state of the ground and the first-excitedstate,and show that there are different laws that the probability density of electron and the period of oscillation changewith the temperature and the electron-LO-phonon coupling constant when the temperature is lower or higher.Andit is obtained that the period of oscillation decreases with increasing the Coulomb bound potential and increases withincreasing the confinement length not only at lower temperatures but also at higher temperatures. 展开更多
关键词 quantum dot QUBIT Coulomb potential temperature effect
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Vertical Forecasting of Temperature, Dissolved Oxygen, pH and Conductivity in the Amadorio Reservoir by Multivariate Methods
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作者 Jorge Bluhm Gutierrez1 Alicia Esparza Martinez +3 位作者 Ernesto Patricio Nufiez Pena Felipe de Jesus Escalona Alcazar Santiago Valle Rodriguez Josefina Huerta Garcia 《Journal of Environmental Science and Engineering(A)》 2014年第2期87-105,共19页
PCA (principal component analysis), CCA (canonical correlation analysis) and PLSR (partial least squares regression) are powerful water quality modeling methods that provide better results than other classical o... PCA (principal component analysis), CCA (canonical correlation analysis) and PLSR (partial least squares regression) are powerful water quality modeling methods that provide better results than other classical ones such as multiple lineal regression. In this work they were used to model four water quality parameters at the Amadorio Reservoir (Alicante, Spain), namely: water temperature, dissolved oxygen, pH and conductivity. The main purpose of this study was to predict the future quality of the water and, thus improve its management. Raw data correspond to daily values of mean wind speed, mean wind direction, maximum wind speed, mean, minimum and maximum air temperature, number of hours below 7 ~C, relative humidity, global solar radiation, total precipitation, evapotranspiration, exploitation volume, inflow, outflow, filtration, depth and Julian day. Two years were considered (2004-2005) to get the calibration (186 days, 4,401 registrations) and validation (185 days, 4,573 registrations) datasets. Models were developed using either all the variables or a reduced subset; furthermore, PLSR yielded the best results. 展开更多
关键词 Water quality management canonical correlation analysis partial least squares
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Effect of Carbonation on Microbiologic Parameters of Refrigerated Bovine Raw Milk
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作者 Marianne Ayumi Shirai Maria Lucia Masson 《Journal of Food Science and Engineering》 2013年第10期557-563,共7页
This study evaluated the effect of carbon dioxide addition on microbiological quality during refrigerated storage of raw milk collected in Curitiba city, Brazil. A three factor-two level full factorial design was used... This study evaluated the effect of carbon dioxide addition on microbiological quality during refrigerated storage of raw milk collected in Curitiba city, Brazil. A three factor-two level full factorial design was used to investigate the effect of the pH (5.8-6.4), storage time (0-10 days) and storage temperature (5-10 ℃), on the responses, namely, mesophiles, psychrotrophs, lipolytic psychrotrophs and proteolytic psychrotrophs counts. Results showed that increase in pH and storage time had significant effect on the microbial count. No significant effect of storage temperature was observed for all the microorganisms studied. All responses were well predicted by selected mathematical models, as denoted by coefficient of determination above 0.95. 展开更多
关键词 Carbon dioxide MICROBIOLOGY shelf life bovine raw milk storage.
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Application study of coupled model between reservoir organic pollutant BOD5-DO and temperature
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作者 LI Yong LI Xin 《Global Geology》 2010年第3期151-154,共4页
The BOD5-DO (Biochemical Oxygen Demand in five days and Dissolved Oxygen) are important indexes that reflect the organic pollution extent of water,but the variation of the indexes is closely related with water tempera... The BOD5-DO (Biochemical Oxygen Demand in five days and Dissolved Oxygen) are important indexes that reflect the organic pollution extent of water,but the variation of the indexes is closely related with water temperature. The study on the coupled mathematical model reflecting the BOD5-DO with temperature is the key to reveal the mechanism of the migration and distribution of BOD5-DO in the water. The authors presented 1-D mathematical model for the three variables in vertical direction,and gave accurate solution for the equations under steady state,the relation among the variables and the method for solving BOD5-DO concentrations at different depth and temperature. 展开更多
关键词 organic pollution biological oxygen demand dissolved oxygen coupled mathematical model
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The below-ground biomass contributes more to wetland soil carbon pools than the above-ground biomass-a survey based on global wetlands
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作者 Yueyan Pan Jiakai Liu +6 位作者 Mingxiang Zhang Peisheng Huang Matt Hipesy Liyi Dai Ziwen Ma Fan Zhang Zhenming Zhang 《Journal of Plant Ecology》 SCIE CSCD 2024年第5期17-28,共12页
The biomass of wetland plants is highly responsive to environmental factors and plays a crucial role in the dynamics of the soil organic carbon(SOC)pool.In this study,we collected and analyzed global data on wetland p... The biomass of wetland plants is highly responsive to environmental factors and plays a crucial role in the dynamics of the soil organic carbon(SOC)pool.In this study,we collected and analyzed global data on wetland plant biomass from 1980 to 2021.By examining 1134 observations from 182 published papers on wetland ecosystems,we created a comprehensive database of wetland plant above-ground biomass(AGB)and below-ground biomass(BGB).Using this database,we analyzed the biomass characteristics of different climate zones,wetland types and plant species globally.Based on this,we analyzed the differences between the biomass of different plant species and the linkage between AGB and BGB and organic carbon.Our study has revealed that wetland plant AGB is greater in equatorial regions but BGB is highest in polar areas,and lowest in arid and equatorial zones.For plant species,the BGB of the Poales is higher than the AGB but Caryophyllales,Cyperales and Lamiales have higher AGB.Moreover,our findings indicate that BGB plays a more significant role in contributing to the organic carbon pool compared to AGB.Notably,when BGB is less than 1 t C ha^(-1),even slight changes in biomass can have a significant impact on the organic carbon pool.And we observed that the SOC increases by 5.7 t C ha^(-1)when the BGB content is low,indicating that the SOC is more sensitive to changes in biomass under such circumstances.Our study provides a basis for the global response of AGB and BGB of wetland plants to organic carbon. 展开更多
关键词 plant biomass global scale organic carbon pool organic carbon sensitivity WETLAND
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SATI algorithm - the calculation of stress aligned HTI stiffness tensor for sandstone reservoir from wireline data
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作者 BRAJANOVSKI Miroslav 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第11期1937-1942,共6页
I present an algorithm that uses cross-dipole wireline data only in order to estimate the HTI stiffness tensor for sandstone formations under in-situ asymmetric lateral (azimuthal) stress conditions.The algorithm is b... I present an algorithm that uses cross-dipole wireline data only in order to estimate the HTI stiffness tensor for sandstone formations under in-situ asymmetric lateral (azimuthal) stress conditions.The algorithm is based on the generalization of terms "excess compliance" and "fracture weakness" developed within the linear slip interface theory for fractured rocks and is applied here to describe the effect of grain contacts in loose sandstones.I introduce the term "plane of weakness" being oriented (aligned) orthogonal to theminimal horizontal principal stress direction in order to describe the overall effective weakness of sandstone caused by the different principal stresses.For the quantification of this phenomenon I use the anisotropic Gassmann model.As a result I am able to calculate a HTI stiffness tensor for the interval length of a saturated sandstone formation and the respective Thomsen's parameters.The input data required for these calculations have to be provided by wireline logging and will consist of porosity,density,P-wave velocity,fast and slow shear wave velocities and oil-water saturation ratio.The algorithm in its current form is applicable to sandstone reservoirs only.Its limitation is based on two assumptions,which state that all the measured anisotropy is induced by the present stress in sandstone and that the unstressed sandstone would be nearly isotropic.From a technical viewpoint this algorithm can be implemented fairly easily in data acquisition and interpretation software relying on correct estimation of anisotropy parameters.It is also cheap because it does not require any additional measurements apart from the cross-dipole logging. 展开更多
关键词 rock physics poroelasticity FRACTURES stress ANISOTROPY S-WAVES
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