Experimental study of head shape effects on shear stress distribution around a single groyne

River hydrodynamicsInteraction with structure

Assessment of 3D-RANS models for the simulation of topographically forced shallow flows

In this work the performance of Reynolds Averaged Navier-Stokes (RANS) simulations to predict the flow structure developed by the presence of a sidewall obstacle in a uniform open-channel shallow flow is discussed. The tested geometry was selected due to its important role in several fluvial applications, such as the control of riverbank erosion and the creation of improved ecological conditions in river restoration applications. The results are compared against experimental laboratory velocity fields obtained after Large Scale Particle Image Velocimetry (LSPIV) measurements. It is shown that the length of reattachment of the separated shear layer generated by the obstacle is well predicted by a Reynolds Stress Model, while classical two-equation models show important limitations. All the performed RANS simulations are unable to properly predict the formation of a secondary gyre region, which develops immediately downstream the obstacle

河川に設置された非典型的な形状の連続型水制周辺の流れの特徴に関する研究

本研究では，非典型的な形状の連続型水制周辺の流れの特徴について，3次元流れ解析モデルSSIIMを用いて調査した。流れとせん断応力の分布を示し，水制間の流れにおける水制形状の効果を考察した。T型とI型水制の比較によって，T型水制の設置は水制周辺にせん断力の大きな領域を創り出すだけでなく，主流路側を均一な流れ場にすることが示された。このことは航路維持にとって着目すべき事ことであり，そして淀み領域においても河川生物および動物相のライフサイクルによって適した環境を提供している。In this study, the features of flow in a sequence of non-typically shaped spur dikes will be examined using a 3-D numerical code, SSIIM. The velocity field and shear stress contour will be presented and the effect of the spaces between the spur dikes on the flow will be discussed. The comparison between the non-typically T-type spur dikes and the straight shape spur dikes showed that by installing the T-type in stream, the distribution of high stress and high energetic zones around the spur dike as well as the main stream is more homogenous. This fact can highlight the capability of T-type spur dikes to provide a better route for navigation, as well as the better stagnation zones which are suitable environment for the life cycle of stream biota and fauna.本研究では，非典型的な形状の連続型水制周辺の流れの特徴について，3次元流れ解析モデルSSIIMを用いて調査した。流れとせん断応力の分布を示し，水制間の流れにおける水制形状の効果を考察した。T型とI型水制の比較によって，T型水制の設置は水制周辺にせん断力の大きな領域を創り出すだけでなく，主流路側を均一な流れ場にすることが示された。このことは航路維持にとって着目すべき事ことであり，そして淀み領域においても河川生物および動物相のライフサイクルによって適した環境を提供している。In this study, the features of flow in a sequence of non-typically shaped spur dikes will be examined using a 3-D numerical code, SSIIM. The velocity field and shear stress contour will be presented and the effect of the spaces between the spur dikes on the flow will be discussed. The comparison between the non-typically T-type spur dikes and the straight shape spur dikes showed that by installing the T-type in stream, the distribution of high stress and high energetic zones around the spur dike as well as the main stream is more homogenous. This fact can highlight the capability of T-type spur dikes to provide a better route for navigation, as well as the better stagnation zones which are suitable environment for the life cycle of stream biota and fauna

The role of cultural intelligence of managers in promoting employees’ collaboration

Collaboration can be a very challenging process precisely because it is a highly intense way of working, requiring new ways of thinking, behavior and ways of operating. Cultural Intelligence (CI) is an antecedent for collaboration . The primary goal of this survey is to investigate the relationship between cultural intelligence of managers and their employees’ collaboration. This research is a descriptive-correlation study where 119 managers and 175 employees are selected by stratified random sampling from the Social Security organization managers and their workers. To measure cultural intelligence, the Iranian version of the cultural intelligence questionnaire is implemented and collaboration is measured using a questionnaire developed by the researcher. The Cronbach's alpha reliability coefficient respectively for cultural intelligence and collaboration questionnaires are 0.933 and 0.813, respectively, which are well above the minimum acceptable limit. Data collected using SPSS 19 and they are analyzed using LISREL 8.54 software packages. The results indicate a significant and positive relationship between cultural intelligence among managers and their employees’ collaboration. As the relationship between motivational and behavioral CI dimensions and collaboration is also determined to be positive and significant. Based on demographic factors such as gender, age and education we cannot comment on the cultural intelligence of managers and employee’s collaboration but having inter-cultural experiences has had a positive impact on the cultural intelligence of managers. Based on the findings obtained we can say that Cultural Intelligence is a key factor, influencing and determining for collaboration

Production, Radiolabeling and Biodistribution Studies of 175Yb-DOTMP as Bone Pain Palliation: 175Yb-DOTMP as bone pain palliation

Bone is the third most common site of metastatic disease. Bone pain is the major source of morbidity associated bone metastasis. Bone-seeking radiopharmaceuticals have been applied for many years. The ability to simultaneously treat multiple sites of disease with a more probable therapeutic effect in earlier phases of metastatic disease is one of the advantages of radiopharmaceuticals. 175Yb is oneof the radioisotopes with suitable properties for developing various nuclear medicine agents. Some of these proper properties include 4.2 days half-life, gamma-rays emitted, radionuclidic purity. Radiopharmaceuticals capable of targeting bone tumors generally use phosphonic acid functionality as the targeting moiety. In this direction cyclic tetraphosphonate, 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraaminomethylenephosphonate (DOTMP) has been labeled with 175YbCl3. Production, quality control and biodistribution studies of 175Yb-DOTMP were targeted in this study. 175Yb chloride with mean specific activity of 31 mCi/mg was obtained by thermal neutron flux (3×1013 n.cm-2.s-1) of a natural Yb2O3 sample (isotopic purity of 31.8% for 174Yb) in the Tehran Research Reactor (TRR). Radiolabeling was completed in one h by the addition of DOTMP at room temperature. The radiochemical purity was determined using ITLC and it was more than 98%. The results of biodistribution animal studies are excellent. It was rapidly taken up in the bone in 2 h after injection (ID/g%=3.92) and reminded after 4 d (ID/g%=3.91)