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| 1 | 种求解非线性无约束优化问题的充分下降的共轭梯度法显示文摘共轭梯度法是一类具有广泛应用的求解大规模无约束优化问题的方法.提出了一种新的非线性共轭梯度(CG)法,理论分析显示新算法在多种线搜索条件下具有充分下降性.进一步证明了新CG算法的全局收敛性定理.最后,进行了大量数值实验,其结果表明与传统的几类CG方法相比,新算法具有更为高效的计算性能. | Tsegay Giday Woldu 张海斌 张鑫 张芳 | 2018 | 运筹学学报2018，22，3： | 6 |
| 2 | Elevational changes in vascular plants richness, diversity, and distribution pattern in Abune Yosef mountain range, Northern Ethiopia显示文摘The aim of this research is to investigate the patterns of vascular plant species richness,diversity,and distribution along an elevation gradient in the Abune Yosef mountain range,Ethiopia.Preferential systematic sampling was employed to collect vegetation and environmental data along the elevation gradient.We found that plant species richness declines monotonically from low to high elevations.Specifically,vascular plant species richness and diversity were lower in the Afroalpine grassland(high elevation)than in the Dry evergreen Afromontane forest and Ericaceous forest(low elevations).In contrast,endemic vascular plant richness was significantly higher in the Afroalpine grassland than in the Dry evergreen Afromontane forest and Ericaceous forest.Elevation showed a significant impact on the richness,diversity,and endemism of vascular plants.According to Sorensen's coefficient,the similarity between Dry evergreen Afromontane forest and Ericaceous forest vegetation types is higher(32%)than the similarity between Ericaceous forest and Afroalpine grassland(18%).Only 5%similarity was recorded between the Dry evergreen Afromontane forest and Afroalpine grassland.Growth forms showed different elevationai richness patterns.Trees and liana increased monotonically up to 3300 m.Shrub and herb richness patterns followed a hump-shaped and inverted hump-shaped pattern along the elevation gradient.The elevation patterns of vascular plant species richness,diversity,and growth form in the present study may be attributed to differences in management intensity,spatial heterogeneity,microclimatic variations,and anthropogenic disturbances. | Kflay Gebrehiwot Sebsebe Demissew Zerihun Woldu Mekbib Fekadu Temesgen Desalegn Ermias Teferi | 2019 | Plant Diversity2019，41，4： | 5 |
| 3 | Floristic diversity and composition of the Biteyu forest in the Gurage mountain chain (Ethiopia): implications for forest conservation显示文摘The Afromontane forests of Ethiopia have been under a serious degradation threat. Assessment of floristic diversity and species composition in Biteyu forest of Gurage mountain chain in the central Ethiopia was conducted to examine the pattern of forest structure. Thirty plots of 30 m×30 m were used to record the vegetation and environmental data using systematic sampling technique. The local name, plant scientific names, DBH, height,species abundance and percentage canopy cover of plant species were recorded. Shannon diversity index and Sorensen's coefficients was used for comparison among communities and similar forests in the country. Threats to the forest biodiversity in Biteyu were determined by counting cattle interference and wood stumps as disturbance indicators. Relative Euclidean Distance measures by using Ward's method(linkage) was applied for cluster analysis. Environmental variables were also recorded in each plot. Woody species population structure, basal area and importance value index were analyzed using spreadsheet programs. Data on species distribution and environmental variables in the forest were analyzed by canonical correspondence analysis. A total of 190 species in 154 genera under 73 families were identified. Twenty species were found to be endemic taxa to the Flora Area. Only three plant community types were identified from the cluster analysis due to the high human influence. The Sorensen's coefficient showed the resemblance of the Biteyu forest with other Dry Evergreen Afromontane forests in the country. Moreover, altitude and slope strongly affect the species composition and structure of Biteyu forest. Given the high anthropogenic influence, high endemism, high dependence of the local community on the forest resources, forest conservation and restoration measures should be done by stakeholders. | Talemos Seta Sebsebe Demissew Zerihun Woldu | 2019 | Journal of Forestry Research2019，30，1： | 4 |
| 4 | Woody species composition and structure of Kuandisha afromontane forest fragment in northwestern Ethiopia显示文摘To investigate the woody species composition,diversity and structure of Kuandisha Afromontane forest,vegetation and environmental data were collected from 53 plots of 10 m 9 50 m for trees and shrubs and 265 subplots of 2 m 9 4 m for seedlings were laid along eight transect lines. The local name, scientific name, abundance,DBH, height and percentage foliage cover of species were recorded. Environmental variables, namely altitude, latitude and longitude as well as disturbance levels were also recorded in each plot. Structure, basal area, importance value index(IVI) and species prioritization were analyzed using spreadsheet programs. Correlation coefficients, frequency, relative frequency, Shannon diversity index,Shannon evenness and vegetation classification were analyzed using an R package. Sixty-six species belonging to40 families were recorded. Fabaceae was the most diverse family consisting of seven species, followed by Euphorbiaceae and Asteraceae. In terms of habit, 29 species were trees, 28 were shrubs, and 9 were lianas. The overall Shannon diversity index was 2.5. The frequency and relative frequency of woody species with DBH C2.5 cm ranged from 1.9 to 92.5 and 0.1 to 5, respectively. Seedling density varied among species ranging from five to 9938 individuals ha-1. The total basal area of woody species having DBH C2.5 cm is 15.3 m2ha-1. The IVI of species ranged from 0.13 for Solanum giganteum Jacq. to 28.4 for Croton macrostachyus Del. The woody vegetation was classified into five community types. Species richness,diversity and evenness of communities were strongly positively correlated. On the other hand, the correlation between disturbance and seedling density, and species richness was strongly negative. Thus, among the recorded woody species, a significant portion was either lacking regeneration or selectively removed for various purposes.The lack of seedlings of those species is mainly attributed to anthropogenic disturbances particularly free grazing. As a result, 14 tree, seven shrub and one liana species were prioritized for conservation and management interventions. | Abiyot Berhanu Sebsebe Demissew Zerihun Woldu Motuma Didita | 2017 | Journal of Forestry Research2017，28，2： | 2 |
| 5 | Outcomes with delayed dorsal vein complex ligation during robotic assisted laparoscopic prostatectomy 显示文摘 | Woldu SL Patel T Shapiro EY | 2013 | Can J Urol2013，20，： | 1 |
| 6 | Evaluation of environmental degradation in Northern Ethiopia using GIS to integrate vegetation,geomorphological,erosion and socio-economic factors显示文摘 | Enrico Feoli Laura Gallizia Vuerich Woldu Zerihun | 2002 | Agriculture Ecosystems and Environment2002，91，： | 1 |
| 7 | Fetal echocardiographie measurements and the need for neonatal surgical intervention in tetralogy of Fallot 显示文摘 | Arya B Levasseur SM Woldu K | 2014 | Pediatr Cardiol2014，35，5： | 1 |
| 8 | The prevalenceof Group B Streptococus recto-vaginal colonization andantimicrobial susceptibility pattern in pregnant mothers at twohospitals of Addis Ababa, Ethiopia显示文摘 | Woldu ZL Teklehaimanot TG Waji STyetal | 2014 | Reprod Health2014，11，： | 1 |
| 9 | Vegetation re sponse to cattle grazing in the Ethiopian highlands显示文摘 | Mwendera E J Saleema M A M Woldu Z | 1997 | Agri- culture Ecosystems ~ Environment1997，64，1： | 1 |
| 10 | The Coffee-Khat Interface in Eastern Ethiopia: A Controversial Land Use and Livelihood Change Scenario显示文摘 | Zenebe Woldu Derbew Belew Taddese Benti | 2015 | Journal of Agricultural Science and Technology(B)2015，5，3： | 1 |
| 11 | Single Institutional Experience with Nephron-sparing Surgery for Pathologic Stage T3bNxM0 Renal Cell Carcinoma Confined to the Renal Vein显示文摘 | Woldu SL Barlow LJ Patel T | 2010 | Urology2010，75，2： | 1 |
| 12 | Overnight urethral stenting af- ter tubularized incised plate urethroplasty for distal hypospadias 显示文摘 | Ritch CR Murphy AM Woldu SL | 2010 | Pediatr Surg Int2010，26，5： | 1 |
| 13 | A novel relationship between the radi cal-seavenging activity of flavonoids and enthalpy of formation revealed with Hartree-Fock computations and thermochemical deduction显示文摘 | WOLDU A S MAI J | 2012 | Redox Report: Communications in Free Radical Research2012，17，3： | 1 |
| 14 | Overnight urethral stent- ing after tubularized incised plate urethroplasty for distal hypospadias 显示文摘 | Ritch CR Murphy AM Woldu SL | 2010 | Pediatr Surg Int2010，26，6： | 1 |
| 15 | Grazing induced biodiversity in the highland ecozone of East Africa 显示文摘 | Woldu Z Mohaed Saleem M A | 2000 | Agriculture Ecosystems and Environment2000，79，1： | 1 |
| 16 | Individual, Organizational, and Manage- rial Predictors of Organizational Innovation: The Case of Poland 显示文摘 | SKUZA A WOLDU H G | 2012 | Journal of Transnational Management2012，17，1： | 1 |
| 17 | Elevation patterns of woody taxa richness in the evergreen Afromontane vegetation of Ethiopia显示文摘Plant species distributions show patterns along elevation gradients. Regardless of the diverse Afromontane vegetation in Ethiopia(AFE), studies of elevation patterns of woody plants are limited and they are restricted to small areas or single/few Mountains. Moreover, there is no general consensus on the patterns of woody taxa distribution by elevation. The objectives of this study were to examine the elevation patterns of woody taxa richness and their relationship with elevation in the AFE. Data were collected and compiled from the Flora of Ethiopia and Eritrea(Vols. 1–7). About 5918 plant species of 243 families were examined and their elevational distributions were recorded. The distributional ranges of woody taxa were aggregated at 19 points(sites) at 100 m intervals starting from 1500 to 3400 m a.s.l. Single-factor analysis of variance(one-way ANOVA) was used to test the hypothesis that mean species richness of woody taxa decreases from the lower to the upper limit of AFE. Simple linear correlation and regression were used to show the relationships of woody taxa richness with elevation. We documented the presence of 505 woody taxa(441 species,31 subspecies and 33 varieties) representing 267 genera and 90 families in the AFE. In terms of habit, 279 taxa are shrubs, 178 are trees and 48 are lianas. The distribution of woody taxa(trees, shrubs and lianas) showed a slight increase at the lower portion and a monotonic decline with increasing elevation. Species richness of trees, shrubs and lianas was negatively and significantly correlated with elevation(r =-0.985,-0.984,-0.981, respectively; all p <0.001). Our hypothesis was accepted because mean richness significantly decreased from the lower to the upper limit of AFE(p <0.001). Generally, monotonic patterns of decline in richness were observed for trees, shrubs and lianas. The contribution of shrubs to total richness increased with increasing elevation whereas that of trees and lianas decreased. | Abiyot Berhanu Zerihun Woldu Sebsebe Demissew | 2017 | Journal of Forestry Research2017，28，4： | 1 |
| 18 | A novel relationship between the radical-scavenging activity of flavonoids and enthalpy of formation revealed with Hartree-Fock computations and thermochemical deduction显示文摘 | WOLDU A S MAI J | 2012 | Redox Rep2012，17，3： | 1 |
| 19 | Absence of association of asporin polymorphisms and osteoarthritis susceptibility in US Caucasians显示文摘 | Atif U Philip A Aponte J Woldu EM Brady S Kraus VB | | 0，，： | 1 |
| 20 | Medicinal plants of the Meinit ethnic group of Ethiopia: An ethnobotanical study显示文摘 | Mirutse Giday Zemede Asfaw Zerihun Woldu | 2009 | Journal of Ethnopharmacology2009，，3： | 1 |
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