The analysis of the risk of flooding upstream from the Imboulou hydroelectric dam on the Léfini River in the Republic of Congo-Brazzaville, focused on the evolution of annual rainfall and flow in the study area d...The analysis of the risk of flooding upstream from the Imboulou hydroelectric dam on the Léfini River in the Republic of Congo-Brazzaville, focused on the evolution of annual rainfall and flow in the study area during the period from 1970 to 2020 before and after the building of the dam in 2005, by applying statistical methods. These methods were used to analyse the spatial and temporal evolution of rainfall and flow at the unique hydrometric station located at the RN2 (National Road N°2) bridge in the village of Mbouambé in the Pool region. This work has shown that rainfall is not the cause of flooding in the Léfini catchment area. The monthly flow coefficient (MFC) showed exceptional flooding from November and December onwards after the dam was built, resulting in a variability of flows, with periods of high and low water. In addition, the annual average flow (AAF) and the maximum average flow (MAF) increased after the dam was built. Maximum average flows (MAF) were higher than annual average flows (AAF) throughout the period of study (1970-2020). The annual and monthly rainfall-runoff relationship showed changes after the dam was built, particularly from 2009 and during the months of November and December. .展开更多
Objective:To determine the larvicidal efficacy of different solvent leaf extract of Ficus benghalensis（F.benghalensis） against Culex tritaeniorhynchus（Cx.tritaeniorhynchus） and Anopheles subpictus（An.subpictus）....Objective:To determine the larvicidal efficacy of different solvent leaf extract of Ficus benghalensis（F.benghalensis） against Culex tritaeniorhynchus（Cx.tritaeniorhynchus） and Anopheles subpictus（An.subpictus）.Methods:Twenty five early third instar larvae of Cx. tritaeniorhynchus and An.subpictus were exposed to various concentrations and were assayed in the laboratory by using the protocol of WHO 2005.The larval mortality was observed after 24 h of treatment.Results:Among three solvent extracts tested the maximum efficacy was observed in the methanol extract.The LC<sub>50</sub> and LC<sub>90</sub> values of F.benghalensis against early third instar of Cx. tritaeniorhynchus and An.subpictus were 100.88.159.76 ppm and 56.66.85.84 ppm.respectively. No mortality was observed in controls.The chi-square values were significant at P【0.05 level. Conclusions:From the results it can be concluded the crude extract of F.benghalensis was an excellent potential for controlling Cx.tritaeniorhynchus and Art.subpictus mosquito larvae.展开更多
This paper presents a simple damage-gradient based elastoplastic model with non linear isotropic hardening in order to regularize the associated initial and boundary value problem (IBVP). Using the total energy equiva...This paper presents a simple damage-gradient based elastoplastic model with non linear isotropic hardening in order to regularize the associated initial and boundary value problem (IBVP). Using the total energy equivalence hypothesis, fully coupled constitutive equations are used to describe the non local damage induced softening leading to a mesh independent solution. An additional partial differential equation governing the evolution of the non local isotropic damage is added to the classical equilibrium equations and associated weak forms derived. This leads to discretized IBVP governed by two algebric systems. The first one, associated with equilibrium equations, is highly non linear and can be solved by an iterative Newton Raphson method. The second one, related to the non local damage, is a linear algebric system and can be solved directly to compute the non local damage variable at each load increment. Two fields, linear interpolation triangular element with additional degree of freedom is terms of the non local damage variable is constructed. The non local damage variable is then transferred from mesh nodes to the quadrature (or Gauss) points to affect strongly the elastoplastic behavior. Two simple 2D examples are worked out in order to investigate the ability of proposed approach to deliver a mesh independent solution in the softening stage.展开更多
这是一个关于寻找与回归的故事。爱尔兰籍导演、插画师以及动画艺术家汤姆·莫尔(Tomm Moore)继《凯尔经的秘密》(The Secret of Kells)之后,又一次将他那烂漫无边的妙笔伸向了自己的家乡,将灵感的触角延伸到那些古老迷人的凯尔特...这是一个关于寻找与回归的故事。爱尔兰籍导演、插画师以及动画艺术家汤姆·莫尔(Tomm Moore)继《凯尔经的秘密》(The Secret of Kells)之后,又一次将他那烂漫无边的妙笔伸向了自己的家乡,将灵感的触角延伸到那些古老迷人的凯尔特传说中去。在这个3D动画愈发充斥着流水线工业气息的年代,《海洋之歌》(Song of the Sea)凭借精美绝伦的手绘画面带来了别样的风情,影片中每一帧每一幕都仿若精工雕刻,看似几笔简约的几何图形却延展堆叠出千变万化的姿态与场景,处处透着爱尔兰传统文化的古朴细腻和深沉醇厚。展开更多
1.Review on previous master planning of Tianjin From 1953 to 1999,with thanks to the great attention of the Municipal Government of Tianjin to the work of master planning,there had been 21 draft master plans finished ...1.Review on previous master planning of Tianjin From 1953 to 1999,with thanks to the great attention of the Municipal Government of Tianjin to the work of master planning,there had been 21 draft master plans finished successively for Tianjin,展开更多
On December 10th,2010 Dow Electronic Materials,a business unit of The Dow Chemical Company,broke ground on its new Eastern China manufacturing facility. The new facility is located at the company’s Zhangjiagang site ...On December 10th,2010 Dow Electronic Materials,a business unit of The Dow Chemical Company,broke ground on its new Eastern China manufacturing facility. The new facility is located at the company’s Zhangjiagang site in Jiangsu province. It will meet the growing demand for materials for printed circuit board (PCB),electronic and indus-展开更多
文摘The analysis of the risk of flooding upstream from the Imboulou hydroelectric dam on the Léfini River in the Republic of Congo-Brazzaville, focused on the evolution of annual rainfall and flow in the study area during the period from 1970 to 2020 before and after the building of the dam in 2005, by applying statistical methods. These methods were used to analyse the spatial and temporal evolution of rainfall and flow at the unique hydrometric station located at the RN2 (National Road N°2) bridge in the village of Mbouambé in the Pool region. This work has shown that rainfall is not the cause of flooding in the Léfini catchment area. The monthly flow coefficient (MFC) showed exceptional flooding from November and December onwards after the dam was built, resulting in a variability of flows, with periods of high and low water. In addition, the annual average flow (AAF) and the maximum average flow (MAF) increased after the dam was built. Maximum average flows (MAF) were higher than annual average flows (AAF) throughout the period of study (1970-2020). The annual and monthly rainfall-runoff relationship showed changes after the dam was built, particularly from 2009 and during the months of November and December. .
文摘Objective:To determine the larvicidal efficacy of different solvent leaf extract of Ficus benghalensis（F.benghalensis） against Culex tritaeniorhynchus（Cx.tritaeniorhynchus） and Anopheles subpictus（An.subpictus）.Methods:Twenty five early third instar larvae of Cx. tritaeniorhynchus and An.subpictus were exposed to various concentrations and were assayed in the laboratory by using the protocol of WHO 2005.The larval mortality was observed after 24 h of treatment.Results:Among three solvent extracts tested the maximum efficacy was observed in the methanol extract.The LC<sub>50</sub> and LC<sub>90</sub> values of F.benghalensis against early third instar of Cx. tritaeniorhynchus and An.subpictus were 100.88.159.76 ppm and 56.66.85.84 ppm.respectively. No mortality was observed in controls.The chi-square values were significant at P【0.05 level. Conclusions:From the results it can be concluded the crude extract of F.benghalensis was an excellent potential for controlling Cx.tritaeniorhynchus and Art.subpictus mosquito larvae.
文摘This paper presents a simple damage-gradient based elastoplastic model with non linear isotropic hardening in order to regularize the associated initial and boundary value problem (IBVP). Using the total energy equivalence hypothesis, fully coupled constitutive equations are used to describe the non local damage induced softening leading to a mesh independent solution. An additional partial differential equation governing the evolution of the non local isotropic damage is added to the classical equilibrium equations and associated weak forms derived. This leads to discretized IBVP governed by two algebric systems. The first one, associated with equilibrium equations, is highly non linear and can be solved by an iterative Newton Raphson method. The second one, related to the non local damage, is a linear algebric system and can be solved directly to compute the non local damage variable at each load increment. Two fields, linear interpolation triangular element with additional degree of freedom is terms of the non local damage variable is constructed. The non local damage variable is then transferred from mesh nodes to the quadrature (or Gauss) points to affect strongly the elastoplastic behavior. Two simple 2D examples are worked out in order to investigate the ability of proposed approach to deliver a mesh independent solution in the softening stage.
文摘这是一个关于寻找与回归的故事。爱尔兰籍导演、插画师以及动画艺术家汤姆·莫尔(Tomm Moore)继《凯尔经的秘密》(The Secret of Kells)之后,又一次将他那烂漫无边的妙笔伸向了自己的家乡,将灵感的触角延伸到那些古老迷人的凯尔特传说中去。在这个3D动画愈发充斥着流水线工业气息的年代,《海洋之歌》(Song of the Sea)凭借精美绝伦的手绘画面带来了别样的风情,影片中每一帧每一幕都仿若精工雕刻,看似几笔简约的几何图形却延展堆叠出千变万化的姿态与场景,处处透着爱尔兰传统文化的古朴细腻和深沉醇厚。
文摘1.Review on previous master planning of Tianjin From 1953 to 1999,with thanks to the great attention of the Municipal Government of Tianjin to the work of master planning,there had been 21 draft master plans finished successively for Tianjin,
文摘On December 10th,2010 Dow Electronic Materials,a business unit of The Dow Chemical Company,broke ground on its new Eastern China manufacturing facility. The new facility is located at the company’s Zhangjiagang site in Jiangsu province. It will meet the growing demand for materials for printed circuit board (PCB),electronic and indus-
