Let S=A_oA_1…A. be a simplex in n-dimensional Euclidean Space E^n with centroid G. The straight line A,G intersects the surface A_0A_1…Ai_l A_i+l…A. of S at the point G, and the circumsphere F of Sat the point Ai(i...Let S=A_oA_1…A. be a simplex in n-dimensional Euclidean Space E^n with centroid G. The straight line A,G intersects the surface A_0A_1…Ai_l A_i+l…A. of S at the point G, and the circumsphere F of Sat the point Ai(i=0,1,…,n). Let the edge-lengths of S be a_ij=A_iA_j(i,j=0,1,…,n, i≠j) and the me dians be m,=A_iG_i(i=O,1,…,n). Following theorem will be proved. Theorem. For the simplex in E^n, wo have sum from i=0 to x A_iA_i≥2n/n+1t=1 sum from i=0 to x m_i; (1) sum from i=0 to x A_i A_i≥2^(2/1)~n(N+1) sum from 0≤i<f≤x a_if; (2) sum from i=v to x (A_i A_i)~2≥4n+1 sum from 0≤i<f≤x ai; (3) The equalities in (1) and (3) hold if and only if the centroid G and the center O of the circumsphere of S are concurrent. The equality in (2) holds if and only if S is regular simplex.展开更多
AIM： To investigate the seroprevalence of Helicobacter pylori （H. pylorl） and its relationship to nutritional fac- tors in female Vietnamese immigrants to Korea. METHODS： A total of 390 female immigrants from Viet...AIM： To investigate the seroprevalence of Helicobacter pylori （H. pylorl） and its relationship to nutritional fac- tors in female Vietnamese immigrants to Korea. METHODS： A total of 390 female immigrants from Vietnam and 206 Korean male spouses participated in the study. Blood samples from 321 female immigrants and 201 Korean male spouses were analyzed for H. py- Iori antibodies. Data on age, sex, alcohol consumption, smoking status, dietary nutritional factors and gastro- intestinal symptoms were collected using question- naires. The daily intakes of the following nutrients were estimated： energy, protein, niacin, lipid, fiber, calcium, iron, sodium, potassium, zinc, folate, cholesterol, and vitamins A, B1, B2, B6, C and E. RESULTS： The prevalence of H. py/ori positivity was lower in the immigrants than in age-matched Koreanfemales （55.7% vs 71.4%, respectively; P 〈 0.0001） and the domestic population of Vietnam. The preva- lence of H. pylori positivity among married couples was 31.7% for both spouses. There were no statistically sig- nificant differences in the incidence of smoking, amount of alcohol consumed, or nutritional factors between the H. pylori-positive and negative groups. CONCLUSION： The prevalence of H. pylori positivity was lower among female Vietnamese immigrants than among Korean females. Nutritional factors did not differ between the H. pylori-positive and negative groups.展开更多
The concept of sustainable livelihood is an attempt to go beyond the conventional definitions and approaches to poverty eradication. These had been found to be too narrow because they focused only on certain aspects o...The concept of sustainable livelihood is an attempt to go beyond the conventional definitions and approaches to poverty eradication. These had been found to be too narrow because they focused only on certain aspects or manifestations of poverty, such as low income, or did not consider other vital aspects of poverty such as vulnerability and social exclusion. It is now recognized that more attention must be paid to the various factors and processes which either constrain or enhance poor people＇s ability to make a living in an economically, ecologically, and socially sustainable manner. Construction of nuclear power plants in Vietnam is in the first step of implementing and will be allocated in Thuan Nam and Ninh Hai districts, Ninh Thuan province, an agricultural and poor province in Vietnam. This requires a large area of land mobilized, thus a part of popupation living in the project area has to move far away. Besides the positive effects of this project, there are significantly negative impacts on the people living in the project areas and nearby, and their livelihoods are seriously affected. This paper aims at assessing the impact of the nuclear power plants construction on the livelihoods of people in two districts in Ninh Thuan province, in order to have mechanisms and policies to support reasonably and effectively, contributing to stabilize people＇s lives and local development.展开更多
Disaster mitigation for marginal communities has become one of the most significant development goals of the 21st century. Vietnam has been reported one of the five most vulnerable nations in the world to climate chan...Disaster mitigation for marginal communities has become one of the most significant development goals of the 21st century. Vietnam has been reported one of the five most vulnerable nations in the world to climate change and so serves as a useful case study in developing appropriate housing solutions after disasters. In addition, some local communities in remote mountainous areas of Vietnam still keep strong vernacular traditions in their housing, especially the typical timber house-on-stilt, which need intense consideration before employing any new techniques of disaster mitigation on them. Perceptions on how to develop a sustainable housing solution for such communities, therefore, is still controversial with very few useful options developed to date. The paper investigates the existing unsafe conditions of traditional houses of a local community in the central highland of Vietnam, exposed to natural disasters, together with an identification of several traditional features of this housing that would be needed to preserve in future construction. Some important gaps of these traditional houses in terms of disaster risk reduction are then displayed to show opportunities where new construction techniques have a high possibility to perform against extreme climate events.展开更多
Long span ultra-high voltage(UHV) transmission lines have serious aeolian vibration problems. To control these vibrations,we improved the energy balance method in the following aspects:the wind power input,the conduct...Long span ultra-high voltage(UHV) transmission lines have serious aeolian vibration problems. To control these vibrations,we improved the energy balance method in the following aspects:the wind power input,the conductor self-damping,and the damper dissipated power. Meanwhile,we built a theoretical mechanical model of β wire dampers and derived energy dissipation calculation formulae. This permits the vibration energy dissipated by β wire dampers can be considered in the energy balance method. Then,we developed a computer program based on the improved energy balance method using Matlab,and analyzed UHV long span ground wires of the Han River long span project in P. R. China. The results show that the combination of β wire dampers and Stockbridge dampers can reduce vibration of UHV long span transmission lines,which provides a reference for research and construction of UHV engineering projects.展开更多
文摘Let S=A_oA_1…A. be a simplex in n-dimensional Euclidean Space E^n with centroid G. The straight line A,G intersects the surface A_0A_1…Ai_l A_i+l…A. of S at the point G, and the circumsphere F of Sat the point Ai(i=0,1,…,n). Let the edge-lengths of S be a_ij=A_iA_j(i,j=0,1,…,n, i≠j) and the me dians be m,=A_iG_i(i=O,1,…,n). Following theorem will be proved. Theorem. For the simplex in E^n, wo have sum from i=0 to x A_iA_i≥2n/n+1t=1 sum from i=0 to x m_i; (1) sum from i=0 to x A_i A_i≥2^(2/1)~n(N+1) sum from 0≤i<f≤x a_if; (2) sum from i=v to x (A_i A_i)~2≥4n+1 sum from 0≤i<f≤x ai; (3) The equalities in (1) and (3) hold if and only if the centroid G and the center O of the circumsphere of S are concurrent. The equality in (2) holds if and only if S is regular simplex.
文摘AIM： To investigate the seroprevalence of Helicobacter pylori （H. pylorl） and its relationship to nutritional fac- tors in female Vietnamese immigrants to Korea. METHODS： A total of 390 female immigrants from Vietnam and 206 Korean male spouses participated in the study. Blood samples from 321 female immigrants and 201 Korean male spouses were analyzed for H. py- Iori antibodies. Data on age, sex, alcohol consumption, smoking status, dietary nutritional factors and gastro- intestinal symptoms were collected using question- naires. The daily intakes of the following nutrients were estimated： energy, protein, niacin, lipid, fiber, calcium, iron, sodium, potassium, zinc, folate, cholesterol, and vitamins A, B1, B2, B6, C and E. RESULTS： The prevalence of H. py/ori positivity was lower in the immigrants than in age-matched Koreanfemales （55.7% vs 71.4%, respectively; P 〈 0.0001） and the domestic population of Vietnam. The preva- lence of H. pylori positivity among married couples was 31.7% for both spouses. There were no statistically sig- nificant differences in the incidence of smoking, amount of alcohol consumed, or nutritional factors between the H. pylori-positive and negative groups. CONCLUSION： The prevalence of H. pylori positivity was lower among female Vietnamese immigrants than among Korean females. Nutritional factors did not differ between the H. pylori-positive and negative groups.
文摘The concept of sustainable livelihood is an attempt to go beyond the conventional definitions and approaches to poverty eradication. These had been found to be too narrow because they focused only on certain aspects or manifestations of poverty, such as low income, or did not consider other vital aspects of poverty such as vulnerability and social exclusion. It is now recognized that more attention must be paid to the various factors and processes which either constrain or enhance poor people＇s ability to make a living in an economically, ecologically, and socially sustainable manner. Construction of nuclear power plants in Vietnam is in the first step of implementing and will be allocated in Thuan Nam and Ninh Hai districts, Ninh Thuan province, an agricultural and poor province in Vietnam. This requires a large area of land mobilized, thus a part of popupation living in the project area has to move far away. Besides the positive effects of this project, there are significantly negative impacts on the people living in the project areas and nearby, and their livelihoods are seriously affected. This paper aims at assessing the impact of the nuclear power plants construction on the livelihoods of people in two districts in Ninh Thuan province, in order to have mechanisms and policies to support reasonably and effectively, contributing to stabilize people＇s lives and local development.
文摘Disaster mitigation for marginal communities has become one of the most significant development goals of the 21st century. Vietnam has been reported one of the five most vulnerable nations in the world to climate change and so serves as a useful case study in developing appropriate housing solutions after disasters. In addition, some local communities in remote mountainous areas of Vietnam still keep strong vernacular traditions in their housing, especially the typical timber house-on-stilt, which need intense consideration before employing any new techniques of disaster mitigation on them. Perceptions on how to develop a sustainable housing solution for such communities, therefore, is still controversial with very few useful options developed to date. The paper investigates the existing unsafe conditions of traditional houses of a local community in the central highland of Vietnam, exposed to natural disasters, together with an identification of several traditional features of this housing that would be needed to preserve in future construction. Some important gaps of these traditional houses in terms of disaster risk reduction are then displayed to show opportunities where new construction techniques have a high possibility to perform against extreme climate events.
基金Funded by the Natural Science Foundation of China (No. 50878093).
文摘Long span ultra-high voltage(UHV) transmission lines have serious aeolian vibration problems. To control these vibrations,we improved the energy balance method in the following aspects:the wind power input,the conductor self-damping,and the damper dissipated power. Meanwhile,we built a theoretical mechanical model of β wire dampers and derived energy dissipation calculation formulae. This permits the vibration energy dissipated by β wire dampers can be considered in the energy balance method. Then,we developed a computer program based on the improved energy balance method using Matlab,and analyzed UHV long span ground wires of the Han River long span project in P. R. China. The results show that the combination of β wire dampers and Stockbridge dampers can reduce vibration of UHV long span transmission lines,which provides a reference for research and construction of UHV engineering projects.
