The formulation of agricultural extension policy and the development of rural regional economy present the relationship of mutual existence,mutual influence and mutual promotion.Therefore,it is necessary to study the ...The formulation of agricultural extension policy and the development of rural regional economy present the relationship of mutual existence,mutual influence and mutual promotion.Therefore,it is necessary to study the agricultural extension policy according to the current situation of rural regional development.Agricultural technology extension system is an organization set up at county and township levels to provide farmers with scientific research achievements and practical technical services on planting,animal husbandry,fishery,forestry,agricultural machinery and water conservancy,and it is an important carrier for implementing the strategy of developing agriculture through science and technology.On the basis of expounding the value and significance of rural regional economic development,this paper analyzes the problems existing in China s rural regional development from the aspects of rural infrastructure and public services,rural labor force s cultural and scientific level,rural grass-roots extension system,etc.,and puts forward corresponding measures against the problems.This study has certain theoretical reference value for promoting the all-round development of China s rural economy and realizing the great strategy of rural revitalization in China.展开更多
Based on the characteristics of large flow rate , low head , short annual operation time , and high reliability of the city flood-control pumping stations , a new-type shaft tubular pumping system featuring a shaft su...Based on the characteristics of large flow rate , low head , short annual operation time , and high reliability of the city flood-control pumping stations , a new-type shaft tubular pumping system featuring a shaft suction box and a siphon-type discharge passage with a vacuum breaker as the cutoff device was developed , which possesses such advantages as simple structure , reliable cutoff , and high energy performance.Taking some pumping stations as the case studies , in the light of the specified operation conditions , the hydraulic optimal design of the shaft-type tubular pumping system was determined and the optimized shape of the system was recommended.The performance prediction based on the computational fluid dynamics methodology was determined and the model test verification was conducted.The results show that the predicted data agree with the experimental head and efficiency so that both methods can be used to determine the performance of a real pumping station.Finally , the in-situ measurements of a pumping station during the commissioning period further verified that the shaft-type tubular pumping station with a siphon discharge passage is of higher efficiency , more reliable and stable.展开更多
Aiming at providing with high-load capability in active vibration control of large-scale rotor system, a new type of active actuator to simultaneously reduce the dangers of low frequency flexural and torsional vibrati...Aiming at providing with high-load capability in active vibration control of large-scale rotor system, a new type of active actuator to simultaneously reduce the dangers of low frequency flexural and torsional vibrations is designed. The actuator employs electro-hydraulic system and can provide a high and circumferential load. To initialize new research, the characteristics of various kinds of active actuators to control rotor shaft vibration are briefly introduced. The purpose of this paper is to introduce the preliminary results via presenting the structure, functions and operating principles, in particular, the working process of the electro-hydraulic system of the new actuator which includes a set of high speed electromagnetic valves and a series of sloping cone-shaped openings, and presenting the transmission relationships among the control parameters from control signals into the valves to active load onto shaft. The course of the work is dynamic, and a series of spatial forces and moments are put on the shaft to get an external resultant force to reduce excitations that induce vibration of shafts. By checking states of vibration, the actuator can control the impulse width and the interval of injection time for applying different control force to a vibration shaft in two circumference directions through the regulating action of a set of combination directional control valves. The results from simulating analysis and experiment show evidence of that this design can satisfy the case of active process of decreasing of flexural and torsional vibrations.展开更多
Shaft development can be documented on the basis of comparative studies of specific shaft lengths and shaft patterns.We calculated the specific length of shafts and the average specific shaft length of the shafts in s...Shaft development can be documented on the basis of comparative studies of specific shaft lengths and shaft patterns.We calculated the specific length of shafts and the average specific shaft length of the shafts in some karst areas and we investigated the relation between the altitude of shaft floors and the specific shaft length.Taking the registered specific shaft lengths and the shaft patterns into consideration,it can be stated that some parts of the shafts developed paragenetically in the studied karst areas.In the Bakony Region,this was caused by surface water influx,rise of karst water level,and their simultaneous effect.As a result,shaft systems,bifurcating shafts and storeyed shafts developed.On glaciokarst areas,shafts may constitute a system with phreatic passages:either because a phreatic environment developed in the vadose zone due to the permanent impoundment of karst water or because a phreatic passage got into the vadose zone since the karst became elevated.On the studied karst areas,the following shaft development types are distinguished:glacial-high mountain surface flood development type(1),glacial-high mountain karst water and surface flood development type(2),glacial karst water and surface flood later phreatic development type(3),shaft with a passage that got into the vadose zone(4).展开更多
The Municipality of Carranglan is a rural community where agriculture is the main source of livelihood. The Kalanguya Ancestral Domain (KAD) is also located in the area, and it provides a home for the Kalanguya indige...The Municipality of Carranglan is a rural community where agriculture is the main source of livelihood. The Kalanguya Ancestral Domain (KAD) is also located in the area, and it provides a home for the Kalanguya indigenous cultural community. They have fled to the area for a variety of reasons. Despite its rural setting, Carranglan is regarded as a first-class municipality and the largest municipality in Nueva Ecija. This study described and documented the socio-economic profile, and existing issues and problems the Kalanguya Indigenous Peoples (IPs) experienced in their milieu, especially in terms of environmental protection. Recognizing and valuing their perspectives is vital for inclusive development. This study also situated the current status and conditions of the IPs, who generally live below the poverty line and face a range of plights and challenges. As part of safeguarding indigenous rights and interests, this study was undertaken after series of consultations with community elders and leaders. Key informant interviews, household surveys, semi-structured interviews, focused-group discussion (FGD), and direct observations were used to elicit information. Many of the respondents are elementary undergraduates which show that the community had lacked access to education. The following are the primary socioeconomic issues confronting IPs: insufficient access to potable water, suboptimal agricultural productivity, meager monthly income, and a dearth of supplementary and alternative livelihood opportunities. Forest fires, landslides, encroachment of illegal loggers, and concerns about wildlife resources are some of the current environmental issues they have encountered. The local population was supportive of plans and actions targeted at improving the environment. This reveals that the IPs possess unique indigenous forest expertise that enables them to properly manage natural resources.展开更多
Leaf nitrogen resorption is very important to Phyllostachys edulis development because the withdrawn nitrogen can help newly emerging and growing culms.However, few studies have focused on the ontogenetic changes in l...Leaf nitrogen resorption is very important to Phyllostachys edulis development because the withdrawn nitrogen can help newly emerging and growing culms.However, few studies have focused on the ontogenetic changes in leaf nitrogen resorption of P. edulis. Here, we examined the variability in mature leaf nitrogen concentrations(Nm), nitrogen resorption efficiency(NRE) and proficiency(NRP or Ns) and leaf-level nitrogen use efficiency(NUE) of the current-, 3 rd-and 5 th-year culms in P.edulis stands under extensive management. Analyses of variance and correlation indicated that patterns of Nm,NRP, NRE and NUE were markedly affected by culm age and leaf nitrogen status. Nm, Nsand NRE were significant higher in younger(current-year) culms with 1-year lifespan leaves, while NUE was markedly higher in older(3 rd-or 5 th-year) culms with 2-year lifespan leaves. Significant linear correlations between Nmand NRP, NRE and NUE,Nmand NUE, Nsand NRE were found for each culm age,and Nmwas significantly positively correlated to NRE for all culms pooled. Higher proficiency in older culms led to higher NUE and lower NRE, these relationships can be modulated by Nm, which in turn, is restrained by leaf N availability and acquisition. Our results revealed that at the intraspecific level, P. edulis can adjust its leaf NRE, NRP,and leaf-level NUE in concert with culm development.Understanding nitrogen resorption characteristics and NUE of P. edulis can help decision-makers design appropriate deforestation strategies and achieve precise N fertilization for sustainable bamboo forest management.展开更多
文摘The formulation of agricultural extension policy and the development of rural regional economy present the relationship of mutual existence,mutual influence and mutual promotion.Therefore,it is necessary to study the agricultural extension policy according to the current situation of rural regional development.Agricultural technology extension system is an organization set up at county and township levels to provide farmers with scientific research achievements and practical technical services on planting,animal husbandry,fishery,forestry,agricultural machinery and water conservancy,and it is an important carrier for implementing the strategy of developing agriculture through science and technology.On the basis of expounding the value and significance of rural regional economic development,this paper analyzes the problems existing in China s rural regional development from the aspects of rural infrastructure and public services,rural labor force s cultural and scientific level,rural grass-roots extension system,etc.,and puts forward corresponding measures against the problems.This study has certain theoretical reference value for promoting the all-round development of China s rural economy and realizing the great strategy of rural revitalization in China.
基金support by the 11th Five Year Key Project of China’s National Scientific Supporting Plan(Grant No.2006BAB04A03)the Hydraulic Engineering Project from the Water Resources Department of Jiangsu Province(Grant No.2010023)
文摘Based on the characteristics of large flow rate , low head , short annual operation time , and high reliability of the city flood-control pumping stations , a new-type shaft tubular pumping system featuring a shaft suction box and a siphon-type discharge passage with a vacuum breaker as the cutoff device was developed , which possesses such advantages as simple structure , reliable cutoff , and high energy performance.Taking some pumping stations as the case studies , in the light of the specified operation conditions , the hydraulic optimal design of the shaft-type tubular pumping system was determined and the optimized shape of the system was recommended.The performance prediction based on the computational fluid dynamics methodology was determined and the model test verification was conducted.The results show that the predicted data agree with the experimental head and efficiency so that both methods can be used to determine the performance of a real pumping station.Finally , the in-situ measurements of a pumping station during the commissioning period further verified that the shaft-type tubular pumping station with a siphon discharge passage is of higher efficiency , more reliable and stable.
基金supported by National Natural Science Foundation of China (No.50475112)National Hi-Tech Research and Development Program of China (863 Program,No.2006AA110112).
文摘Aiming at providing with high-load capability in active vibration control of large-scale rotor system, a new type of active actuator to simultaneously reduce the dangers of low frequency flexural and torsional vibrations is designed. The actuator employs electro-hydraulic system and can provide a high and circumferential load. To initialize new research, the characteristics of various kinds of active actuators to control rotor shaft vibration are briefly introduced. The purpose of this paper is to introduce the preliminary results via presenting the structure, functions and operating principles, in particular, the working process of the electro-hydraulic system of the new actuator which includes a set of high speed electromagnetic valves and a series of sloping cone-shaped openings, and presenting the transmission relationships among the control parameters from control signals into the valves to active load onto shaft. The course of the work is dynamic, and a series of spatial forces and moments are put on the shaft to get an external resultant force to reduce excitations that induce vibration of shafts. By checking states of vibration, the actuator can control the impulse width and the interval of injection time for applying different control force to a vibration shaft in two circumference directions through the regulating action of a set of combination directional control valves. The results from simulating analysis and experiment show evidence of that this design can satisfy the case of active process of decreasing of flexural and torsional vibrations.
文摘Shaft development can be documented on the basis of comparative studies of specific shaft lengths and shaft patterns.We calculated the specific length of shafts and the average specific shaft length of the shafts in some karst areas and we investigated the relation between the altitude of shaft floors and the specific shaft length.Taking the registered specific shaft lengths and the shaft patterns into consideration,it can be stated that some parts of the shafts developed paragenetically in the studied karst areas.In the Bakony Region,this was caused by surface water influx,rise of karst water level,and their simultaneous effect.As a result,shaft systems,bifurcating shafts and storeyed shafts developed.On glaciokarst areas,shafts may constitute a system with phreatic passages:either because a phreatic environment developed in the vadose zone due to the permanent impoundment of karst water or because a phreatic passage got into the vadose zone since the karst became elevated.On the studied karst areas,the following shaft development types are distinguished:glacial-high mountain surface flood development type(1),glacial-high mountain karst water and surface flood development type(2),glacial karst water and surface flood later phreatic development type(3),shaft with a passage that got into the vadose zone(4).
文摘The Municipality of Carranglan is a rural community where agriculture is the main source of livelihood. The Kalanguya Ancestral Domain (KAD) is also located in the area, and it provides a home for the Kalanguya indigenous cultural community. They have fled to the area for a variety of reasons. Despite its rural setting, Carranglan is regarded as a first-class municipality and the largest municipality in Nueva Ecija. This study described and documented the socio-economic profile, and existing issues and problems the Kalanguya Indigenous Peoples (IPs) experienced in their milieu, especially in terms of environmental protection. Recognizing and valuing their perspectives is vital for inclusive development. This study also situated the current status and conditions of the IPs, who generally live below the poverty line and face a range of plights and challenges. As part of safeguarding indigenous rights and interests, this study was undertaken after series of consultations with community elders and leaders. Key informant interviews, household surveys, semi-structured interviews, focused-group discussion (FGD), and direct observations were used to elicit information. Many of the respondents are elementary undergraduates which show that the community had lacked access to education. The following are the primary socioeconomic issues confronting IPs: insufficient access to potable water, suboptimal agricultural productivity, meager monthly income, and a dearth of supplementary and alternative livelihood opportunities. Forest fires, landslides, encroachment of illegal loggers, and concerns about wildlife resources are some of the current environmental issues they have encountered. The local population was supportive of plans and actions targeted at improving the environment. This reveals that the IPs possess unique indigenous forest expertise that enables them to properly manage natural resources.
基金supported by the Key Project of National Key Research and Development Plans(2016YFC0500204)the Chinese National Basic Research Program(2013BAC03B05)+1 种基金the Key Project for the Strategic Science Plan in Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences(No.2012ZD007)State Forestry Administration project948(2014-4-58)
文摘Leaf nitrogen resorption is very important to Phyllostachys edulis development because the withdrawn nitrogen can help newly emerging and growing culms.However, few studies have focused on the ontogenetic changes in leaf nitrogen resorption of P. edulis. Here, we examined the variability in mature leaf nitrogen concentrations(Nm), nitrogen resorption efficiency(NRE) and proficiency(NRP or Ns) and leaf-level nitrogen use efficiency(NUE) of the current-, 3 rd-and 5 th-year culms in P.edulis stands under extensive management. Analyses of variance and correlation indicated that patterns of Nm,NRP, NRE and NUE were markedly affected by culm age and leaf nitrogen status. Nm, Nsand NRE were significant higher in younger(current-year) culms with 1-year lifespan leaves, while NUE was markedly higher in older(3 rd-or 5 th-year) culms with 2-year lifespan leaves. Significant linear correlations between Nmand NRP, NRE and NUE,Nmand NUE, Nsand NRE were found for each culm age,and Nmwas significantly positively correlated to NRE for all culms pooled. Higher proficiency in older culms led to higher NUE and lower NRE, these relationships can be modulated by Nm, which in turn, is restrained by leaf N availability and acquisition. Our results revealed that at the intraspecific level, P. edulis can adjust its leaf NRE, NRP,and leaf-level NUE in concert with culm development.Understanding nitrogen resorption characteristics and NUE of P. edulis can help decision-makers design appropriate deforestation strategies and achieve precise N fertilization for sustainable bamboo forest management.