在地下水脆弱性评价的GOD法和DRASTIC模型的基础上,提出了VLDA模型,其中V为包气带岩性(lithology of vadose zone)、L为土地利用方式(pattern of land use)、D为地下水埋深(groundwater depth)、A为含水层特征(aquifer characteristics...在地下水脆弱性评价的GOD法和DRASTIC模型的基础上,提出了VLDA模型,其中V为包气带岩性(lithology of vadose zone)、L为土地利用方式(pattern of land use)、D为地下水埋深(groundwater depth)、A为含水层特征(aquifer characteristics)。以新疆焉耆县平原区为例,在GIS平台上,利用VLDA模型评价该地区潜水的脆弱性,并与2009年9月潜水硝酸盐含量进行对比,结果表明:焉耆县平原区孔隙潜水脆弱性相对较高的区域面积占40.83%,主要分布在西北部地区(包括库尔勒市城市地下水水源地)和焉耆镇一带;潜水高脆弱性区与潜水硝酸盐含量高值区基本一致,说明应用VLDA模型开展地下水脆弱性评价具有可行性。为解决城市供水与地下水脆弱性这一对矛盾,应加强该地区地下水污染防治工作,并应坚持"以预防为主,防、治结合"的原则。展开更多
Groundwater plays important roles as one of the essential source of water supplies of the studied area. Consequently, it needs to be prevented from contamination. In this study, two methods have been examined, namely ...Groundwater plays important roles as one of the essential source of water supplies of the studied area. Consequently, it needs to be prevented from contamination. In this study, two methods have been examined, namely DRASTIC （depth to groundwater, net recharge, aquifer media, soil map, topography, impact of vadose zone and hydraulic conductivity） and VLDA （vadose zone lithoiogy, land use patterns, depth to groundwater and aquifer media） to model a map of groundwater vulnerability for contamination of the basin. The standard DRASTIC vulnerability maps classified the basin of four vulnerability index zones： very low （34%）, low （13%）, moderate （48%） and high （5%）. While the VLDA model classified the area into four categories as well： low （2%）, moderate （44%）, high（53%） and very high （1%）. The results demonstrate that there is a significant dissimilarity in the rate of vulnerability. Validation of the constructed maps is required to confirm the validity of the theoretical sympathetic of current hydrogeological conditions. In this study, nitrate concentration analysis was selected as a contamination indicator to validate the result. The nitrate concentration of two different seasons （dry and wet） was analyzed from （30） watering wells, considerable variations in nitrate concentration from dry to wet seasons had been noted. Consequently, it points toward that groundwater in the HSB （Halabja Saidsadiq Basin） is capable to receive the contaminant due to suitability of overlies strata in terms of geological and hydrogeological conditions. Based on this confirmation, the result exemplifies that the degree and distribution of vulnerability level acquired using VLDA model is more sensible than that attained from the standard DRASTIC method .In addition, the DRASTIC models need to be modified based on the land use pattern, which clarifies the role of human activity on the vulnerability system.展开更多
Groundwater aquifer in the HSB (Halabja and Saidsadiq Basin) is considered being one of the most important aquifers in terms of water supplying in Kurdistan Region, NE of Iraq. The growing of economics, irrigation and...Groundwater aquifer in the HSB (Halabja and Saidsadiq Basin) is considered being one of the most important aquifers in terms of water supplying in Kurdistan Region, NE of Iraq. The growing of economics, irrigation and agricultural activities inside the basin makes it of the main essentials to the region. Therefore, pollution of groundwater is of specific worry as groundwater resources are the principal source of water for drinking, agriculture, irrigation and industrial activities. Thus, the best and practical arrangement is to keep the pollution of groundwater through. The current study aims at the evaluation of the vulnerability of groundwater aquifers of the study area. Two models were applied, to be specific VLDA and COP to develop maps of groundwater vulnerability for contamination. The VLDA model classified the area into four classes of vulnerability with each covered area: low (2%), moderate (44%), high (53%) and very high (1%). While four vulnerability classes were accomplished dependent on COP model including very low, low, moderate and high vulnerability classes with coverage areas of 1%, 37%, 2% and 60% respectively. To confirm the suitability of each map for assessment of groundwater vulnerability in the area, it required to be validated of the theoretical sympathetic of current hydrogeological conditions. In this study, groundwater age evaluated utilizing tritium isotopes investigation and applied it to validate the vulnerability results. Based on this validation, the outcome exhibits that the vulnerability classes acquired utilizing VLDA model are more predictable contrasted with the COP model.展开更多
In this paper,a novel dynamic addressing scheme for wireless sensor networks(WSNs)is proposed by using variable length coding.A WSN is typically composed of numerous tiny energy-constrained sensor nodes with limited i...In this paper,a novel dynamic addressing scheme for wireless sensor networks(WSNs)is proposed by using variable length coding.A WSN is typically composed of numerous tiny energy-constrained sensor nodes with limited information processing and data storage capabilities;thus,the energy-efficient strategy is the key issue in designing protocols for WSN.Traditional addressing strategies adopt flat addressing(static and uniform addresses)for sensor nodes.However,the proposed variable length dynamic addressing(VLDA)for sensor nodes is based on the fact that different nodes in the network have uneven traffic loads.Therefore,nodes with more data to receive or send are allocated with shorter addresses.Whether a node is busy or not is determined by the network traffic distribution(NTD),which is defined as the number of data packets each node has received or sent in a period of time.Sensor nodes’energy is saved by VLDA scheme;hence,the wireless sensor network’s lifetime is extended.In the simulation,a 20%improvement has been achieved through the addressing scheme compared to traditional flat addressing.展开更多
文摘在地下水脆弱性评价的GOD法和DRASTIC模型的基础上,提出了VLDA模型,其中V为包气带岩性(lithology of vadose zone)、L为土地利用方式(pattern of land use)、D为地下水埋深(groundwater depth)、A为含水层特征(aquifer characteristics)。以新疆焉耆县平原区为例,在GIS平台上,利用VLDA模型评价该地区潜水的脆弱性,并与2009年9月潜水硝酸盐含量进行对比,结果表明:焉耆县平原区孔隙潜水脆弱性相对较高的区域面积占40.83%,主要分布在西北部地区(包括库尔勒市城市地下水水源地)和焉耆镇一带;潜水高脆弱性区与潜水硝酸盐含量高值区基本一致,说明应用VLDA模型开展地下水脆弱性评价具有可行性。为解决城市供水与地下水脆弱性这一对矛盾,应加强该地区地下水污染防治工作,并应坚持"以预防为主,防、治结合"的原则。
文摘Groundwater plays important roles as one of the essential source of water supplies of the studied area. Consequently, it needs to be prevented from contamination. In this study, two methods have been examined, namely DRASTIC （depth to groundwater, net recharge, aquifer media, soil map, topography, impact of vadose zone and hydraulic conductivity） and VLDA （vadose zone lithoiogy, land use patterns, depth to groundwater and aquifer media） to model a map of groundwater vulnerability for contamination of the basin. The standard DRASTIC vulnerability maps classified the basin of four vulnerability index zones： very low （34%）, low （13%）, moderate （48%） and high （5%）. While the VLDA model classified the area into four categories as well： low （2%）, moderate （44%）, high（53%） and very high （1%）. The results demonstrate that there is a significant dissimilarity in the rate of vulnerability. Validation of the constructed maps is required to confirm the validity of the theoretical sympathetic of current hydrogeological conditions. In this study, nitrate concentration analysis was selected as a contamination indicator to validate the result. The nitrate concentration of two different seasons （dry and wet） was analyzed from （30） watering wells, considerable variations in nitrate concentration from dry to wet seasons had been noted. Consequently, it points toward that groundwater in the HSB （Halabja Saidsadiq Basin） is capable to receive the contaminant due to suitability of overlies strata in terms of geological and hydrogeological conditions. Based on this confirmation, the result exemplifies that the degree and distribution of vulnerability level acquired using VLDA model is more sensible than that attained from the standard DRASTIC method .In addition, the DRASTIC models need to be modified based on the land use pattern, which clarifies the role of human activity on the vulnerability system.
文摘Groundwater aquifer in the HSB (Halabja and Saidsadiq Basin) is considered being one of the most important aquifers in terms of water supplying in Kurdistan Region, NE of Iraq. The growing of economics, irrigation and agricultural activities inside the basin makes it of the main essentials to the region. Therefore, pollution of groundwater is of specific worry as groundwater resources are the principal source of water for drinking, agriculture, irrigation and industrial activities. Thus, the best and practical arrangement is to keep the pollution of groundwater through. The current study aims at the evaluation of the vulnerability of groundwater aquifers of the study area. Two models were applied, to be specific VLDA and COP to develop maps of groundwater vulnerability for contamination. The VLDA model classified the area into four classes of vulnerability with each covered area: low (2%), moderate (44%), high (53%) and very high (1%). While four vulnerability classes were accomplished dependent on COP model including very low, low, moderate and high vulnerability classes with coverage areas of 1%, 37%, 2% and 60% respectively. To confirm the suitability of each map for assessment of groundwater vulnerability in the area, it required to be validated of the theoretical sympathetic of current hydrogeological conditions. In this study, groundwater age evaluated utilizing tritium isotopes investigation and applied it to validate the vulnerability results. Based on this validation, the outcome exhibits that the vulnerability classes acquired utilizing VLDA model are more predictable contrasted with the COP model.
文摘In this paper,a novel dynamic addressing scheme for wireless sensor networks(WSNs)is proposed by using variable length coding.A WSN is typically composed of numerous tiny energy-constrained sensor nodes with limited information processing and data storage capabilities;thus,the energy-efficient strategy is the key issue in designing protocols for WSN.Traditional addressing strategies adopt flat addressing(static and uniform addresses)for sensor nodes.However,the proposed variable length dynamic addressing(VLDA)for sensor nodes is based on the fact that different nodes in the network have uneven traffic loads.Therefore,nodes with more data to receive or send are allocated with shorter addresses.Whether a node is busy or not is determined by the network traffic distribution(NTD),which is defined as the number of data packets each node has received or sent in a period of time.Sensor nodes’energy is saved by VLDA scheme;hence,the wireless sensor network’s lifetime is extended.In the simulation,a 20%improvement has been achieved through the addressing scheme compared to traditional flat addressing.
