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Applicability of Community Periodontal Index Teeth and Random Half-mouth Examination to Gingival Bleeding Assessment in Untreated Adult Population in Beijing
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作者 Jing-hua Zhang 《Chinese Medical Sciences Journal》 CAS CSCD 2012年第1期41-45,共5页
Objective To assess whether Community Periodontal Index (CPI) teeth and random half-mouth methods are representative of full-mouth method in gingival bleeding examination. Methods Data from 1000 untreated adults (age ... Objective To assess whether Community Periodontal Index (CPI) teeth and random half-mouth methods are representative of full-mouth method in gingival bleeding examination. Methods Data from 1000 untreated adults (age > 18) collected in Beijing from January 2000 to January 2001 were utilized in the analysis. Half of the subjects were examined by Gingival Bleeding Index (GBI) and the other half by Sulcus Bleeding Index (SBI). The data were sorted out and calculated according to CPI teeth and random half-mouth teeth methods. The results of the 2 methods were separately compared with those of full-mouth examination. Results There was a significant difference between CPI teeth method and full-mouth examination (P<0.05) in both GBI and SBI. In contrast, compared with full-mouth examination, significant difference was not observed in diagonal or ipsilateral half-mouth results in SBI (P>0.05), nor in diagonal half-mouth results in GBI (P>0.05) Conclusions The results of CPI teeth method on gingival bleeding could not reflect the full-mouth situation. Ipsilateral and diagonal half-mouth results can serve as a substitute for full-mouth results in SBI, while diagonal half-mouth results in GBI. 展开更多
关键词 牙龈出血 牙齿 随机 北京 社区 评估 适用性 考试
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Nigella sativa oil as a treatment for gingivitis: A randomized active-control trial
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作者 Ishrat Rahman Afrah Mohammed +4 位作者 Manal A.AlSheddi Alanoud Algazlan Alanoud Alwably Mamata Hebbal Maha Galal Omar 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2023年第3期129-138,共10页
Objective: To assess the clinical anti-inflammatory and antimicrobial efficacy of Nigella sativa oil compared with chlorhexidine in patients with gingivitis. Methods: A double-blind, randomized clinical trial was cond... Objective: To assess the clinical anti-inflammatory and antimicrobial efficacy of Nigella sativa oil compared with chlorhexidine in patients with gingivitis. Methods: A double-blind, randomized clinical trial was conducted in patients having chronic generalized gingivitis. Patients were randomly assigned to receive Nigella sativa oil(n=18) or chlorhexidine(n=19). The following assessments were made on day 0 and day 15: plaque index, gingival index, gingival IL-6 and IL-18 levels were measured using ELISA, plaque colony-forming units, and alpha-hemolytic Streptococcus strains. Data were analyzed using parametric and non-parametric tests and Fisher’s exact test.Results: Both interventions reduced plaque index and gingival index scores(P<0.000 1). The Nigella sativa oil group was better at lowering IL-6(P=0.007 6) than the chlorhexidine group(P=0.145), although there was no change in IL-18 levels(P>0.05). The post-intervention plaque index and gingival index scores and inflammatory cytokine levels between the two groups were not significantly different. Both interventions caused a significant reduction in the plaque colony-forming units(P<0.000 1), reducing pathogenic bacteria: Streptococcus mitis, Streptococcus oralis, Streptococcus sanguinis, and Streptococcus parasanguinis in the chlorhexidine group(50%)(P=0.103 1), and the Nigella sativa oil group(20%)(P=0.739 5). Conclusions: Nigella sativa oil had anti-inflammatory and antibacterial activities, reducing biofilm formation and disrupting the colonization of pathogenic bacteria essential for the progression of periodontal disease. Nigella sativa oil could offer an alternative therapy for treating gingivitis and may prevent associated systemic diseases and improve overall health outcomes. 展开更多
关键词 CHLORHEXIDINE Mouth rinse INTERLEUKIN gingival index Plaque index
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低GI枸杞杂粮代餐粉的体外消化特性
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作者 田玲丽 马娇 +2 位作者 刘军 范艳丽 刘敦华 《食品工业科技》 CAS 北大核心 2024年第12期342-350,共9页
为探究低血糖生成指数(Glycemic index,GI)枸杞杂粮代餐粉的体外消化特性,本研究对各原料粉及代餐粉的基本组分、吸水率及吸水膨胀率、淀粉组分、淀粉水解率及估计血糖生成指数(Estimate Glycemic index,eGI)值进行测定与分析,并通过体... 为探究低血糖生成指数(Glycemic index,GI)枸杞杂粮代餐粉的体外消化特性,本研究对各原料粉及代餐粉的基本组分、吸水率及吸水膨胀率、淀粉组分、淀粉水解率及估计血糖生成指数(Estimate Glycemic index,eGI)值进行测定与分析,并通过体外模拟胃肠消化方法对比分析了各原料粉及代餐粉中蛋白质水解率、总酚含量、黄酮含量及抗氧化活性的变化。结果表明,代餐粉中脂肪和粗纤维含量相较于各原料粉处于偏低水平。各原料粉及代餐粉的高温吸水率为常温吸水率的2倍左右,其中代餐粉吸水率最低(常温条件下吸水率为0.27%±0.05%,高温条件下吸水率为0.59%±0.05%)。代餐粉中快速消化淀粉含量(40.4%±0.003%)及eGI值(23.4)相较于各原料粉均达到最低,而慢消化淀粉和抗性淀粉含量均相对较高。体外模拟胃肠消化实验中,各原料粉及代餐粉蛋白质水解率均逐渐升高且水解主要以胃部为主,其中代餐粉蛋白水解率相对较高;总酚含量在胃肠消化期间均呈上升趋势且代餐粉在消化结束时含量达到最高(7.26 mg/g)。黄酮含量在模拟胃消化过程中明显增加,而在模拟肠消化中含量下降。DPPH自由基和ABTS+自由基清除率在模拟胃消化过程中随时间延长显著(P<0.05)上升,而在模拟肠消化过程中随时间延长呈先上升后降低趋势,但整体变化幅度较为平缓。综上所述,枸杞杂粮代餐粉适合作为低GI原料或产品且具有良好的抗氧化能力,对于杂粮制品的开发具有一定指导的意义。 展开更多
关键词 gi 杂粮 枸杞 代餐粉 体外消化特性
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Compressive near-field millimeter wave imaging algorithm based on Gini index and total variation mixed regularization
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作者 Jue Lyu Dong-Jie Bi +7 位作者 Bo Liu Guo Yi Xue-Peng Zheng Xi-Feng Li Li-Biao Peng Yong-Le Xie Yi-Ming Zhang Ying-Li Bai 《Journal of Electronic Science and Technology》 CAS CSCD 2023年第1期65-74,共10页
A compressive near-field millimeter wave(MMW)imaging algorithm is proposed.From the compressed sensing(CS)theory,the compressive near-field MMW imaging process can be considered to reconstruct an image from the under-... A compressive near-field millimeter wave(MMW)imaging algorithm is proposed.From the compressed sensing(CS)theory,the compressive near-field MMW imaging process can be considered to reconstruct an image from the under-sampled sparse data.The Gini index(GI)has been founded that it is the only sparsity measure that has all sparsity attributes that are called Robin Hood,Scaling,Rising Tide,Cloning,Bill Gates,and Babies.By combining the total variation(TV)operator,the GI-TV mixed regularization introduced compressive near-field MMW imaging model is proposed.In addition,the corresponding algorithm based on a primal-dual framework is also proposed.Experimental results demonstrate that the proposed GI-TV mixed regularization algorithm has superior convergence and stability performance compared with the widely used l1-TV mixed regularization algorithm. 展开更多
关键词 Millimeter wave(MMW) Compressed sensing(CS) gini index(gi) Total variation(TV) Signal processing Image reconstruction
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基于RS与GIS技术的喀斯特煤矿区生态环境质量评价:以盘州市为例 被引量:1
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作者 刘发勇 田祥贵 何林 《中国矿业》 北大核心 2024年第2期63-68,共6页
针对喀斯特煤矿区特殊的地质环境特点,综合考虑影响生态环境质量的因素,选取与煤矿开采活动关联的指标因子,建立喀斯特煤矿区生态环境质量综合评价指标体系。通过对评价指标的分级处理,利用RS与GIS技术对指标因子进行单一评价分析,并在A... 针对喀斯特煤矿区特殊的地质环境特点,综合考虑影响生态环境质量的因素,选取与煤矿开采活动关联的指标因子,建立喀斯特煤矿区生态环境质量综合评价指标体系。通过对评价指标的分级处理,利用RS与GIS技术对指标因子进行单一评价分析,并在ArcGIS栅格数据空间叠加分析计算的支持下,采用综合指数法和层次分析法对盘州市生态环境质量进行综合评价,从而得到盘州市喀斯特煤矿区的生态环境质量等级。评价结果显示,盘州市生态环境质量大部分较好,优良等级占比达75.03%,但部分区域山高坡陡、植被覆盖度低及煤矿开采区相对应的生态环境情况较差;在生态环境保护及经济发展的规划中应以生态环境质量较差的区域为主,加强矿山土地复垦、植树造林等一系列生态恢复措施。在综合评价时引入生态环境质量网格化评价方法,通过一定范围内生态环境质量等级面积及权重的定量计算,为区域生态环境质量评价提供参考。 展开更多
关键词 喀斯特煤矿区 生态环境质量 giS技术 指标体系 生态修复
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基于机-热-电多参量信号特征的GIS隔离开关状态评估方法
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作者 周秀 吴旭涛 +3 位作者 田天 白金 张昭宇 李军浩 《电力工程技术》 北大核心 2024年第1期220-228,共9页
气体绝缘开关(gas insulated switchgear,GIS)设备中的隔离开关故障往往是机械、热、电气多物理量综合作用的结果,从微小缺陷发展至严重故障的过程中,会产生异常振动、温度、局部放电多种参量信号,同时测量并分析GIS隔离开关的多参量信... 气体绝缘开关(gas insulated switchgear,GIS)设备中的隔离开关故障往往是机械、热、电气多物理量综合作用的结果,从微小缺陷发展至严重故障的过程中,会产生异常振动、温度、局部放电多种参量信号,同时测量并分析GIS隔离开关的多参量信息对于准确获取其运行状态具有重要意义。文中通过在实体220 kV GIS实验平台上模拟隔离开关最为常见的接触不良缺陷,研究不同接触状态时振动信号、温度变化和局部放电信号的演化规律,获得其与设备状态之间的对应关系,结合健康指数理论和改进层次分析法,提出基于多参量特征的GIS隔离开关综合评估方法。使用该方法开展现场测试,其检查结果与多参量综合评估方法的的分析结果相吻合。文中的研究为GIS隔离开关状态的带电检测提供了一种可行性较高的多参量融合分析新方法。 展开更多
关键词 气体绝缘开关(giS) 隔离开关 振动信号 温度变化 局部放电 健康指数:改进层次分析法
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基于GIS的滇中地区人居环境适宜性评价
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作者 张雪 刘璐 游珍 《云南地理环境研究》 2024年第1期8-18,共11页
科学评估人居环境适宜性,有助于城市可持续发展,实现人类活动与自然环境和谐共处。研究基于地理信息系统(GIS)技术,以1 km×1 km栅格为基本研究单元,构建了滇中地区地形、水文、植被、气候单要素和综合人居环境适宜性评价模型与标准... 科学评估人居环境适宜性,有助于城市可持续发展,实现人类活动与自然环境和谐共处。研究基于地理信息系统(GIS)技术,以1 km×1 km栅格为基本研究单元,构建了滇中地区地形、水文、植被、气候单要素和综合人居环境适宜性评价模型与标准,从空间上定量评价了滇中地区的人居环境适宜性空间分布特征。研究表明:(1)从自然单要素的适宜性评价结果来看,气候、水文和地被的适宜性评价结果均以比较适宜为主;而地形是该区域人居环境适宜性的主要限制要素,且在空间上分区比较破碎,以一般适宜地区为主,主要分布在区域的西部和北部。(2)从人居环境适宜性综合评价结果来看,整体的人居环境状况较好,空间上呈片状分布的特征,临界适宜和一般适宜地区区域点总面积的80%以上;昆明市的不适宜地区面积占比最高,高度适宜地区面积较小但多数分布在楚雄州,曲靖市整体的人居环境状况最好。(3)结合人口数量和密度空间分布数据来看,人口分布与人居环境适宜性在空间分布上存在较高一致性,滇中地区近90%的人分布在临界适宜、一般适宜和比较适宜地区。 展开更多
关键词 人居环境适宜性 人居环境指数 地理信息系统 滇中地区
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Therapeutic effect of neurogrowth factor in the treatment of gingival pain and swelling in patients with dental pulp necrosis after root canal therapy
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作者 Yan Li Hai-Yan Cheng 《Journal of Hainan Medical University》 2017年第20期150-153,共4页
Objective: To explore the clinical efficacy of neurogrowth factor in the treatment of gingival pain and swelling in patients with dental pulp necrosis after root canal therapy and the effect on the serum inflammatory ... Objective: To explore the clinical efficacy of neurogrowth factor in the treatment of gingival pain and swelling in patients with dental pulp necrosis after root canal therapy and the effect on the serum inflammatory cytokines. Methods: A total of 156 patients with gingival pain and swelling after root canal therapy due to dental pulp necrosis were included in the study and randomized into the control group (n=78) and teh treatment group (n=78). The patients in the control group were given metronidazole tablets. On the above basis, the patients in the treatment group were given local injection of neurogrowth factors. 10-day treatment was regarded as one course, and the patients were continuously treated for 2 courses. The improvement of clinical symptoms before and after treatment in the two groups was evaluated. Gingival sulcus index and serum inflammatory cytokines before and after treatment in the two groups were detected and compared. Results: When compared with before treatment, the periodontal soft tissue swelling, tooth mobility, and periapical pain scores after treatment in the two groups were significantly reduced, and those in the treatment group were significantly lower than those in the control group. When compared with before treatment, the gingival sulcus bleeding index 1 and 2 courses after treatment in the two groups was significantly reduced, and that 2 courses after treatment was significantly lower than that after 1 course treatment. The gingival sulcus bleeding index 1 and 2 courses after treatment in the treatment group was significantly lower than that in the control group. When compared with before treatment, the serum IL-8 and IL-6 levels after treatment in the two groups, and TNF-α level after treatment in the treatment group were significantly reduced, and the above indicators in the treatment group were significantly lower than those in the control group. Conclusions: The neurogrowth factors in the treatment of gingival pain and swelling in patients with dental pulp necrosis after root canal therapy can effectively improve the clinical symptoms, and inhibit the inflammatory reaction, with a significant efficacy. 展开更多
关键词 Dental pulp necrosis Root CANAL therapy gingival PAIN and SWELLING Neurogrowth factor Inflammatory cytokine gingival SULCUS bleeding index
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基于GIS与层次分析模型的生态旅游舒适度评价方法 被引量:1
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作者 韩燕妮 《桉树科技》 2023年第2期27-34,共8页
为了提升区域范围内的生态旅游质量,针对生态旅游舒适度分析结果片面及冗余性的问题,提出基于地理信息系统(Geographic Information System,GIS)与层次分析(Analytic Hierarchy Process,AHP)模型的生态旅游舒适度评价方法。建立评价指... 为了提升区域范围内的生态旅游质量,针对生态旅游舒适度分析结果片面及冗余性的问题,提出基于地理信息系统(Geographic Information System,GIS)与层次分析(Analytic Hierarchy Process,AHP)模型的生态旅游舒适度评价方法。建立评价指标体系,通过两两对比判断矩阵及方根法确定生态旅游舒适度评价指标的权重值。结果显示:该方法所构建的评价指标体系信度较高,获取生态旅游舒适度评价结果准确,方法可行。 展开更多
关键词 giS 层次分析模型 生态旅游 舒适度评价 指标体系 等级划分图
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杂粮的有效利用——低GI(Glycaemic Index)食品的必要性(英文) 被引量:1
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作者 片山直美 《中国粮油学报》 EI CAS CSCD 北大核心 2007年第6期64-70,共7页
研究了在体重过多人群的食生活里导入杂粮的有效性以及杂粮食谱的营养价值。营养价值参考了日本厚生劳动省发表的"日本人食事摄取基准",这资料标示了目标热量、各种营养成分的目标摄取量以及许多项目的极限程度。因为极限程... 研究了在体重过多人群的食生活里导入杂粮的有效性以及杂粮食谱的营养价值。营养价值参考了日本厚生劳动省发表的"日本人食事摄取基准",这资料标示了目标热量、各种营养成分的目标摄取量以及许多项目的极限程度。因为极限程度与年龄、性别和生理状态有关,在此我们以普通生活的成人作为基准。杂粮中的营养成分,苋的热量358kcal、蛋白质12.7g、脂肪6.0g、糖质64.9g、食物纤维7.4g、Na 1.0mg、P540mg、Fe 9.4mg、Ca 160mg、K 600mg、Cu 0.92mg、Zn 5.8mg、Mn 6.14mg、维生素A 2.0ug以及微量的维生素C。经过研讨设计了营养平衡最佳的食谱为:糙米200g、苋50g、andeskinua50g、大豆110g、甘薯200g、绿黄色蔬菜(小青菜)300g、鸡蛋55g以及泥鳅100g。食用这个食谱可以摄取热量2007 kcal(是基准摄取量的100%),其他营养成分的摄取量与基准摄取量相比分别为:蛋白质173%、脂肪72%、碳水化物105%、K 332%、Ca262%、Mg 267%、P 250%、Fe 420%、Zn 183%、Cu 343%、VA 126%、VD 100%、VE 142%、VK 940%、VB1237%、VB2174%、烟碱酸201%、VB6218%、VB12375%、叶酸350%、泛酸160%、VC 176%、食物纤维185%、盐分5%以及Mn 273%。不足的盐分可以使用调味料来补充。氨基酸的摄取量推测是基准值的100%。蛋白质:脂肪:碳水化物的比例是19.0∶18.0∶63.0,与理想的平衡比接近。 展开更多
关键词 杂粮 gi(Glycaemic index) 营养平衡食物 超重人群
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基于GIS的田间精细化管理——以玉米种业田间种植为例
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作者 段保霞 《智慧农业导刊》 2023年第18期17-20,共4页
该文介绍基于GIS的田间精细化管理平台的设计与实现。以玉米田间种植指标的数字化为基础,采集田间种植过程关键指标数据,获取环境要素信息,对田间空间数据通过GIS进行转换、处理和分析,用以制定种植计划、规范田间管理、保证品种质量、... 该文介绍基于GIS的田间精细化管理平台的设计与实现。以玉米田间种植指标的数字化为基础,采集田间种植过程关键指标数据,获取环境要素信息,对田间空间数据通过GIS进行转换、处理和分析,用以制定种植计划、规范田间管理、保证品种质量、建立种植绩效考核体系及提高工作效率。同时,当进入种子加工厂后,通过产品数字化技术及质量追溯平台,对产品生产加工、包装对应、仓库管理、订单、物流和销售等各个环节的信息进行有效采集、对应和管理,从而进行产品生命周期的全程监控,实现物流跟踪、质量控制及追溯等功能。 展开更多
关键词 giS 种植指标 精细化管理 标准化流程 田间种植
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A Novel Hybrid Method for Measuring the Spatial Autocorrelation of Vehicular Crashes: Combining Moran’s Index and Getis-Ord G<sub>i</sub><sup style='margin-left:-7px;'>*</sup>Statistic 被引量:1
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作者 Azad Abdulhafedh 《Open Journal of Civil Engineering》 2017年第2期208-221,共14页
Spatial autocorrelation is a measure of the correlation of an observation with other observations through space. Most statistical analyses are based on the assumption that the values of observations are independent of... Spatial autocorrelation is a measure of the correlation of an observation with other observations through space. Most statistical analyses are based on the assumption that the values of observations are independent of one another. Spatial autocorrelation violates this assumption, because observations at near-by locations are related to each other, and hence, the consideration of spatial autocorrelations has been gaining attention in crash data modeling in recent years, and research have shown that ignoring this factor may lead to a biased estimation of the modeling parameters. This paper examines two spatial autocorrelation indices: Moran’s Index;and Getis-Ord Gi* statistic to measure the spatial autocorrelation of vehicle crashes occurred in Boone County roads in the state of Missouri, USA for the years 2013-2015. Since each index can identify different clustering patterns of crashes, therefore this paper introduces a new hybrid method to identify the crash clustering patterns by combining both Moran’s Index and Gi*?statistic. Results show that the new method can effectively improve the number, extent, and type of crash clustering along roadways. 展开更多
关键词 Spatial AUTOCORRELATION Moran’s index Getis-Ord gi* Statistic Vehicle Crashes
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Integrating Lithostratigraphic Units and GIS-Analysis Techniques to Modified Surface Water Quality Index 被引量:1
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作者 Majed Ibrahim Habes Al-Mashakbeh 《Journal of Environmental Protection》 2016年第8期1104-1112,共10页
The purpose of this study is to investigate the effect of using Bicarbonate and Calcium parameters as alternatives to the lithostratigraphic units covered the catchment area, on water quality index (WQI) values that h... The purpose of this study is to investigate the effect of using Bicarbonate and Calcium parameters as alternatives to the lithostratigraphic units covered the catchment area, on water quality index (WQI) values that have been implemented with GIS technique at Wadi Al-Arab Dam. The analyzed results (by WQI method) have been used to depict water quality for the two approaches. Based on physico-chemical parameters, the calculated values for WQI over the 3-year for study period were 169, 168, and 157, respectively. While the WQI values were 184, 183 and 172, respectively, as a result of incorporated Bicarbonate and Calcium parameters in WQI calculations that significantly contributed to increasing the WQI. The elevated values may be attributed to the influence of carbonate stone dissolution and mechanical erosion under weathering conditions that are prevalent during winter season in the catchment area. As a consequence of lithostratigraphic unites product and GIS technique integration and normalization processes, most of water quality ranks are good and only autumn season has poor water quality in the 2012 and 2013, while in 2014 it has good water quality in the same season. The WQI values increase in general trend from winter to autumn seasons during the study period that may be referred to outflow by daily consumption, evaporation rising, and seepage water. The analysis shows that the modified water quality values of the Wadi Al-Arab Dam Reservoir (WADR) vary after using Bicarbonate and Calcium parameters by constant value. Generally, the results signify that the WADR is not polluted based on the physical and chemical characteristics of water. 展开更多
关键词 giS Lithostratigraphic Units Water Quality index Surface Water RESERVOIR SEASONALITY Irbid Wadi Al-Arab Dam JORDAN
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Spatial/temporal indexing and information visualization genre for environmental digital libraries 被引量:3
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作者 CHEN Su-shing GRUNWALD Sabine 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第11期1235-1248,共14页
Protecting and preserving our environmental systems require the ability to understand the spatio-temporal distri- bution of soils, parent material, topography, and land cover as well as the effects of human activities... Protecting and preserving our environmental systems require the ability to understand the spatio-temporal distri- bution of soils, parent material, topography, and land cover as well as the effects of human activities on ecosystems. Space-time modelling of ecosystems in an environmental digital library is essential for visualizing past, present, and future impacts of changes occurring within such landscapes (e.g., shift in land use practices). In this paper, we describe three novel features, spa- tio-temporal indexing, visualization, and geostatistical genre, for the environmental digital library, Environmental Visualization and Geographic Enterprise System (ENVISAGE), currently in progress at the University of Florida. 展开更多
关键词 数字图书馆 giS 地理信息系统 搜索系统
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Research of the Differential Uplifting in the Palongzangbu Region Based on the Synthesis of the Watershed Index and Seismic Data
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作者 Wang Lin Zhao Yan +2 位作者 Tian Qinjian Li Wenqiao Xu Yueren 《Earthquake Research in China》 CSCD 2018年第1期64-79,共16页
Research on the differential uplifting in the Palongzangbu region is crucial to understanding the tectonic deformation mechanism and establishing the model of the faulted blocks in the region of the east structural kn... Research on the differential uplifting in the Palongzangbu region is crucial to understanding the tectonic deformation mechanism and establishing the model of the faulted blocks in the region of the east structural knot.In this paper,based on the ASTER-30m DEM,we calculate the hypsometry index(HI)of 19 watersheds in the Palongzangbu region,and study the differential uplifting in this region combining with seismic data,the ground deposition and erosion process.The result shows that the spatial distribution of the HI value can reflect the differential uplifting in the study area.Differential uplifting exists within different zones,and there are 2 relative strong uplifting centers.One center is near the east structural knot,and the other lies between the Lhari fault and Nujiang fault at their converging segment.Also,the watershed evolution,seismic activity,and ground deposition and erosion process are closely related to each other,and they constitute a chain of evidence which reveals the whole process from the tectonic movement underground to the landform evolution on the surface. 展开更多
关键词 WATERSHED HYPSOMETRY index giS DEM Differential Tectonic UPLIFTING East Structural KNOT
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Detection and Mapping of Water Quality Variation in the Godavari River Using Water Quality Index, Clustering and GIS Techniques
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作者 Indrani Gupta Awkash Kumar +1 位作者 Chandrakant Singh Rakesh Kumar 《Journal of Geographic Information System》 2015年第2期71-84,共14页
The objective of this research is to develop a tool for planning and managing the water quality of River Godavari. This is achieved by classifying the pollution levels of Godavari River into several categories using w... The objective of this research is to develop a tool for planning and managing the water quality of River Godavari. This is achieved by classifying the pollution levels of Godavari River into several categories using water quality index and a clustering approach that ensure simple but accurate information about the pollution levels and water characteristics at any point in Godavari River in Maharashtra. The derived water quality indices and clusters were then visualized by using a Geographical Information System to draw thematic maps of Godavari River, thus making GIS as a decision support system. The obtained maps may assist the decision makers in managing and controlling pollution in the Godavari River. This also provides an effective overview of those spots in the Godavari River where intensified monitoring activities are required. Consequently, the obtained results make a major contribution to the assessment of the State’s water quality monitoring network. Three significant groups (less polluted, moderately and highly polluted sites) were detected by Cluster Analysis method. The results of Discriminant Analysis revealed that five parameters?i.e.?pH, Dissolved Oxygen (DO), Faecal Coliform (FC), Total Coliform (TC) and Ammonical Nitrogen (NH3-N) were necessary for analysis in spatial variation. Using discriminant function developed in the analysis, 100% of the original sites were correctly classified. 展开更多
关键词 giS Water Quality index CLUSTER ANALYSIS DISCRIMINANT ANALYSIS
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Evaluation of Groundwater Quality in the Deep Maastrichtian Aquifer of Senegal Using Multivariate Statistics and Water Quality Index-Based GIS
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作者 Djim M. L. Diongue Laila Sagnane +3 位作者 Huguette Emvoutou Maria Faye Ibra D. Gueye Serigne Faye 《Journal of Environmental Protection》 CAS 2022年第11期819-841,共23页
A regional groundwater quality evaluation was conducted in the deep Maastrichtian aquifer of Senegal through multivariate statistical analysis and a GIS-based water quality index using physicochemical data from 232 bo... A regional groundwater quality evaluation was conducted in the deep Maastrichtian aquifer of Senegal through multivariate statistical analysis and a GIS-based water quality index using physicochemical data from 232 boreholes distributed over the whole country. The aim was to 1) identify the water types and likely factors influencing the hydrochemistry, and 2) determine the suitability of groundwater for drinking and irrigation. Results showed that sodium, chloride, and fluoride are highly correlated with electrical conductivity (EC) reflecting the significant contribution of these elements to groundwater mineralization. The principal component analysis evidenced: 1) salinization processes (loaded by Na<sup>+</sup>, K<sup>+</sup>, EC, Cl<sup>-</sup>, F<sup>-</sup> and HCO<sub>3</sub>-</sup>) controlled by water/rock interaction, seawater intrusion and cation exchange reactions;2) dolomite dissolution loaded by the couple Ca<sup>2+</sup> and Mg<sup>2+</sup> and 3) localized mixing with upper aquifers and gypsum dissolution respectively loaded by NO<sub>3</sub>-</sup> and SO<sub>4</sub>2-</sup>. The hierarchical clustering analysis distinguished four clusters: 1) freshwater (EC = 594 μs/cm) with mixed-HCO<sub>3</sub> water type and ionic contents below WHO standard;2) brackish (Na-mixed) water type with moderate mineralization content (1310 μs/cm), 3) brackish (Na-Cl) water type depicted by high EC values (3292 μs/cm) and ionic contents above WHO and 4) saline water with Na-Cl water type and very high mineralization contents (5953 μs/cm). The mapping of the groundwater quality index indicated suitable zones for drinking accounting for 54% of the entire area. The occurrence of a central brackish band and its vicinity, which were characterized by high mineralization, yielded unsuitable groundwater for drinking and agricultural uses. The approach used in this study was valuable for assessing groundwater quality for drinking and irrigation, and it can be used for regional studies in other locations, particularly in shallow and vulnerable aquifers. 展开更多
关键词 Groundwater Quality index MAASTRICHTIAN Statistical Analysis giS
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基于GIS技术的玉米作物种植区主要气象灾害风险评估模型构建
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作者 王洪明 李茂桐 崔兆韵 《现代电子技术》 2023年第19期107-110,共4页
气象灾害风险的综合评估指标选取全面性较差,导致玉米作物种植区气象灾害风险评估准确性较差,为此文中构建基于GIS技术的玉米作物种植区主要气象灾害风险评估模型。基于自然灾害风险形成机制,从气象灾害危险性、暴露性、脆弱性、防灾能... 气象灾害风险的综合评估指标选取全面性较差,导致玉米作物种植区气象灾害风险评估准确性较差,为此文中构建基于GIS技术的玉米作物种植区主要气象灾害风险评估模型。基于自然灾害风险形成机制,从气象灾害危险性、暴露性、脆弱性、防灾能力四个方面选择主要气象灾害风险评价指标,以其归一化处理为前提,通过熵权法完成其权重的计算后,运用GIS技术实现种植区主要气象灾害风险的空间分析,构建主要气象灾害风险评估模型,划分主要气象灾害风险等级,实现气象灾害风险评估模型的构建。实验结果表明,该模型可实现单一、多气象灾害风险评估,有利于玉米作物生长。 展开更多
关键词 giS技术 玉米作物 气象灾害 风险评估模型 防灾减灾 熵权法 归一化 风险指数
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西帕依固龈液联合培氟沙星对慢性牙周炎患者治疗效果、疼痛程度及GI、PLI、SBI的影响
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作者 谢庆军 李明亮 方玉 《中国医学创新》 CAS 2023年第29期115-118,共4页
目的:探讨西帕依固龈液联合培氟沙星对慢性牙周炎患者治疗效果、疼痛程度及牙龈指数(GI)、牙菌斑指数(PLI)、龈沟出血指数(SBI)的影响。方法:选取2021年5月—2022年5月宜春市第二人民医院收治的86例慢性牙周炎患者作为本次研究对象,按... 目的:探讨西帕依固龈液联合培氟沙星对慢性牙周炎患者治疗效果、疼痛程度及牙龈指数(GI)、牙菌斑指数(PLI)、龈沟出血指数(SBI)的影响。方法:选取2021年5月—2022年5月宜春市第二人民医院收治的86例慢性牙周炎患者作为本次研究对象,按到院顺序的奇偶性将其分为对照组与观察组,每组43例。所有患者均行常规治疗,在此基础上,对照组使用米诺环素,观察组使用西帕依固龈液联合培氟沙星治疗。对比两组治疗后临床效果、PLI、牙周袋深度(PD)、GI、SBI、不良反应总发生率以及疼痛程度。结果:观察组总有效率高达97.67%明显高于对照组的76.74%(P<0.05);治疗前,两组PD、PLI、SBI、GI对比,差异均无统计学意义(P>0.05);治疗后,观察组上述指标均低于对照组(P<0.05)。治疗前,两组视觉模拟评分法(VAS)评分对比,差异均无统计学意义(P>0.05);治疗后,观察组VAS评分显著低于对照组(P<0.05)。观察组不良反应总发生率为4.65%,低于对照组的25.58%(P<0.05)。结论:临床治疗慢性牙周炎患者采用西帕依固龈液与培氟沙星结合,可进一步提高临床效果。不仅改善了患者因慢性牙周炎带来的疼痛感,还降低了PD、PLI、SBI、GI,并减少了不良反应的发生,两种药物相结合效果更为显著,可促进患者快速恢复。 展开更多
关键词 西帕依固龈液 培氟沙星 慢性牙周炎 疼痛程度 牙龈指数 牙菌斑指数 龈沟出血指数
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基于GIS的宜章县耕地质量等级评价
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作者 文雯 罗林涛 +3 位作者 杜金花 谢大声 凌宏辉 刘云华 《湖南农业科学》 2023年第8期76-83,共8页
以宜章县为研究区域,从立地条件、理化性状、养分状况、农田管理、生态环境这5个方面中选取15个评价指标,基于GIS建立合适的耕地质量评价模型和评价体系,运用层次分析法和特尔斐法确定评价区域耕地质量等级。结果表明:宜章县的29528.11 ... 以宜章县为研究区域,从立地条件、理化性状、养分状况、农田管理、生态环境这5个方面中选取15个评价指标,基于GIS建立合适的耕地质量评价模型和评价体系,运用层次分析法和特尔斐法确定评价区域耕地质量等级。结果表明:宜章县的29528.11 hm^(2)耕地可分为3大类共10个等级,高、中、低产耕地占比分别为31.16%、43.58%和25.26%;15个耕地评价因子中,隶属度均值小于0.7的是有效磷和灌溉能力2个因子,隶属度均值在0.7~0.8之间的有速效钾和地形部位2个因子,清洁程度、有机质、障碍因素、有效土层厚度、土壤容重、农田林网化程度6个因子的隶属度均值在0.9以上,生物多样性、排水能力、质地构型、耕层质地和pH值5个因子隶属度均值在0.8~0.9之间。根据研究结果,从加强高产耕地保育力度、明确中产耕地的改良方略、强化低产耕地质量提升措施3个方面提出了加强宜章县耕地质量保育的建议。 展开更多
关键词 耕地质量 等级评价 giS 评价指标 宜章县
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