Aggregation function

聚合函数
  • 文章类型: Journal Article
    计算机断层扫描(CT)是临床实践中广泛使用的无创诊断工具。然而,临床CT成像中常用的小分子碘化对比剂(ICAs)具有在体内非特异性分布等局限性,通过肾脏快速清除,等。,导致狭窄的成像时间窗口。相比之下,现有的纳米级ICA面临着结构不确定性等挑战,重现性差,低碘含量,和一致性问题。在这项研究中,提出了一种利用聚集诱导发光剂(AIEgen)设计和制造一种单组分纳米ICA(即,BioDHU-CTNP)在激活时表现出独特的聚集效应。小尺寸的BioDHU-CT纳米粒子表现出优异的肿瘤靶向能力,可以释放经AIEgen修饰的ICA,释放效率高达88.45%,在肿瘤区域高表达的活性氧的激活下。释放的ICA在肿瘤区域执行原位聚集能力,这可以提高CT造影剂的保留效率,延长了成像时间窗,提高了肿瘤区域的成像质量。
    Computed tomography (CT) is a widely utilized noninvasive diagnostic tool in clinical practice. However, the commonly employed small molecular iodinated contrast agents (ICAs) in clinical CT imaging have limitations such as nonspecific distribution in body, rapid clearance through kidneys, etc., leading to a narrow imaging time window. In contrast, existing nano-sized ICAs face challenges like structural uncertainty, poor reproducibility, low iodine content, and uniformity issues. In this study, a novel approach is presented utilizing the aggregation-induced emission luminogen (AIEgen) to design and fabricate a kind of monocomponent nano-sized ICA (namely, BioDHU-CT NPs) that exhibits a unique aggregation effect upon activation. The small sized BioDHU-CT nanoparticles exhibit excellent tumor targeting capabilities and can release ICA modified with AIEgen with a high release efficiency up to 88.45%, under the activation of reactive oxygen species highly expressed in tumor regions. The released ICA performs in situ aggregation capability in the tumor region, which can enhance the retention efficiency of CT contrast agents, extending the imaging time window and improving the imaging quality in tumor regions.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    这里,我们提出了一种改进的水质指数(WQI)模型,用于使用科克港评估沿海水质,爱尔兰,作为案例研究。该模型涉及通常的四个WQI组件-选择包含的水质指标,指标值的子索引,子索引加权和子索引聚合-进行改进,以使该方法更加客观和数据驱动,并且不太容易出现日蚀和歧义错误。该模型使用机器学习算法,XGBoost,根据对总体水质状况的相对重要性,对水质指标进行排序和选择。在有数据的十项指标中,透明度,溶解的无机氮,氨态氮,BOD5,叶绿素,夏季选择温度和正磷酸盐,而总有机氮,溶解的无机氮,pH值,透明度和溶解氧选择冬季。使用国家推荐的沿海水质指导值开发的线性插值函数用于水质指标的子索引,并将XGBoost排名与排名顺序质心加权方法结合使用以确定子指标权重值。测试了八个子索引聚合函数-五个来自现有的WQI模型,三个由作者提出。将计算出的指标与使用多元线性回归(MLR)方法获得的指标进行比较,并将R2和RMSE用作聚集函数性能的指标。作者提出的加权二次均值函数(夏季R2=0.91,RMSE=4.4;冬季R2=0.97,RMSE=3.1)和未加权算术平均函数(夏季R2=0.92,RMSE=3.2;冬季R2=0.97,RMSE=3.2)被确定为最佳函数,与其他函数相比,显示出减少的日食和歧义问题。
    Here, we present an improved water quality index (WQI) model for assessment of coastal water quality using Cork Harbour, Ireland, as the case study. The model involves the usual four WQI components - selection of water quality indicators for inclusion, sub-indexing of indicator values, sub-index weighting and sub-index aggregation - with improvements to make the approach more objective and data-driven and less susceptible to eclipsing and ambiguity errors. The model uses the machine learning algorithm, XGBoost, to rank and select water quality indicators for inclusion based on relative importance to overall water quality status. Of the ten indicators for which data were available, transparency, dissolved inorganic nitrogen, ammoniacal nitrogen, BOD5, chlorophyll, temperature and orthophosphate were selected for summer, while total organic nitrogen, dissolved inorganic nitrogen, pH, transparency and dissolved oxygen were selected for winter. Linear interpolation functions developed using national recommended guideline values for coastal water quality are used for sub-indexing of water quality indicators and the XGBoost rankings are used in combination with the rank order centroid weighting method to determine sub-index weight values. Eight sub-index aggregation functions were tested - five from existing WQI models and three proposed by the authors. The computed indices were compared with those obtained using a multiple linear regression (MLR) approach and R2 and RMSE used as indicators of aggregation function performance. The weighted quadratic mean function (R2 = 0.91, RMSE = 4.4 for summer; R2 = 0.97, RMSE = 3.1 for winter) and the unweighted arithmetic mean function (R2 = 0.92, RMSE = 3.2 for summer; R2 = 0.97, RMSE = 3.2 for winter) proposed by the authors were identified as the best functions and showed reduced eclipsing and ambiguity problems compared to the others.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    考虑到人口正在迅速老龄化,对家庭老化技术的需求,它可以提供可靠的,对人类活动的不显眼的监控,预计将扩大。本研究的重点是改进姿态检测问题的解决方案,这是跌倒检测系统的一部分。跌倒检测,使用MicrosoftKinect传感器获取的深度图,是一个两阶段的方法。我们专注于系统的第一阶段,也就是说,从深度图的姿态识别。对于躺着的姿势检测,提出了一种新的混合FRSystem。在系统中,调查了两个规则集,第一个是基于领域知识创建的,第二个是基于粗糙集理论诱导的。此外,考虑了有和没有知识度量的两种推理聚合方法。结果表明,知识测度的新公理定义,我们提出的建议对推理的有效性有积极的影响,减少集合中规则数量的规则归纳法保持了它。
    Considering that the population is aging rapidly, the demand for technology for aging-at-home, which can provide reliable, unobtrusive monitoring of human activity, is expected to expand. This research focuses on improving the solution of the posture detection problem, which is a part of fall detection system. Fall detection, using depth maps obtained by the Microsoft Kinect sensor, is a two-stage method. We concentrate on the first stage of the system, that is, pose recognition from a depth map. For lying pose detection, a new hybrid FRSystem is proposed. In the system, two rule sets are investigated, the first one created based on a domain knowledge and the second induced based on the rough set theory. Additionally, two inference aggregation approaches are considered with and without the knowledge measure. The results indicate that the new axiomatic definition of knowledge measures, which we propose has a positive impact on the effectiveness of inference and the rule induction method reducing the number of rules in a set maintains it.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    一种量化渗滤液污染潜力的工具,称为修订后的渗滤液污染指数(r-LPI),已经开发了。它是使用模糊德尔菲层次分析法(FDAHP)开发的。制定需要四个主要步骤:参数选择,重量计算,参数的归一化,和参数的聚合。使用模糊德尔菲法(FDM)选择了分为三个标准的11个渗滤液参数。使用模糊层次分析法(FAHP)计算参数和标准的相对权重,和评级曲线用于参数的归一化。选择汇总函数是制定综合指标的最关键步骤之一。在这项研究中,简要讨论了r-LPI的概念,并检查了14种不同的聚集函数,以估计垃圾渗滤液的污染潜力。根据参数权重的责任和不责任,模棱两可,日食,和恒定的功能行为,消除了8个聚集函数。对其余六个聚集函数进行敏感性分析。此外,量化了由于参数汇总而丢失的信息。根据调查结果,结论是,加权加性函数有效地量化了垃圾渗滤液的污染潜力,因此推荐用于r-LPI。
    A tool to quantify the pollution potential of leachate, termed the revised leachate pollution index (r-LPI), has been developed. It was developed using the fuzzy Delphi analytic hierarchy process (FDAHP). The formulation entails four major steps: parameter selection, weight calculation, normalization of parameters, and aggregation of the parameters. Eleven leachate parameters categorized into three criteria were selected using the fuzzy Delphi method (FDM). The relative weights of the parameters and the criteria were computed using the fuzzy analytic hierarchy process (FAHP), and rating curves were used for normalization of the parameters. The selection of an aggregation function is one of the most critical steps in the development of a composite indicator. In this study, the concept of r-LPI was briefly discussed and 14 different aggregation functions were examined to estimate the pollution potential of landfill leachate. Based on accountability and non-accountability of weights of the parameters, ambiguity, eclipsing, and constant functional behavior, 8 aggregation functions were eliminated. The remaining six aggregation functions were subjected to sensitivity analysis. Furthermore, information lost due to aggregation of parameters was quantified. Based on the findings, it was concluded that the weighted additive function effectively quantifies the pollution potential of landfill leachate and thus recommended for the r-LPI.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    多标准决策分析是药物获益-风险评估的一种定量方法,通过将所有获益和风险汇总在一个分数中,可以进行一致的比较。多准则决策分析由几个部分组成,其中之一是效用(或损失)得分函数,它定义了收益和风险如何聚合成一个单一的数量。虽然线性效用评分是收益-风险评估中使用最广泛的方法之一,人们认识到,这可能会导致反直觉的决定,例如,建议使用极低获益或高风险的治疗方法。为了克服这个问题,分数构建的替代方法,即,产品,多元线性和规模损失得分模型,被建议。然而,到目前为止,关于这些模型隐含的差异的大多数论点都是启发式的。在这项工作中,我们考虑了四个模型来计算汇总的效用/损失分数,并在许多不同场景的广泛模拟研究中比较了它们的性能,在一个案例研究中。结果发现,与线性和多元线性模型相比,产品和规模损失得分模型在大多数情况下提供了更直观的治疗推荐决策,并且对标准中的相关性更稳健。
    Multi-criteria decision analysis is a quantitative approach to the drug benefit-risk assessment which allows for consistent comparisons by summarising all benefits and risks in a single score. The multi-criteria decision analysis consists of several components, one of which is the utility (or loss) score function that defines how benefits and risks are aggregated into a single quantity. While a linear utility score is one of the most widely used approach in benefit-risk assessment, it is recognised that it can result in counter-intuitive decisions, for example, recommending a treatment with extremely low benefits or high risks. To overcome this problem, alternative approaches to the scores construction, namely, product, multi-linear and Scale Loss Score models, were suggested. However, to date, the majority of arguments concerning the differences implied by these models are heuristic. In this work, we consider four models to calculate the aggregated utility/loss scores and compared their performance in an extensive simulation study over many different scenarios, and in a case study. It is found that the product and Scale Loss Score models provide more intuitive treatment recommendation decisions in the majority of scenarios compared to the linear and multi-linear models, and are more robust to the correlation in the criteria.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    评估供水能力对于满足利益相关者的需求至关重要,特别是在地中海地区。该地区已被确定为气候变化热点,以及由于人口增长和灌溉面积的扩大,对水的需求不断增加的地区。赫罗特河集水区(2500公里(2),法国)是一个典型的例子,自1960年代以来一直观察到排放的负面趋势。在这种情况下,当地利益攸关方首先需要了解过去控制水资源和需求演变的过程,以评估未来的供水能力,并预测用户未来可能面临的紧张局势。提出了一个为期10天的建模框架,以评估水资源在过去50年中是否能够满足水的需求。使用水文模型和大坝管理模型评估了供水。估计了家庭和农业部门的水需求动态。计算供水能力指数以评估子流域规模上满足水需求的程度和频率。模拟径流动态与校准和验证期间的观测结果非常吻合。自1980年代以来,国内用水需求大幅增加,其特点是夏季出现季节性高峰。下游子盆地的农业需求增加,而灌溉面积减少的上游则减少。因此,尽管在1961年至1980年之间满足了大多数水需求,但自1980年代以来,夏季的灌溉需求有时无法满足。这项工作是评估流域未来水资源分配能力可能变化的第一步,利用未来的气候变化,大坝管理和用水方案。
    Assessing water supply capacity is crucial to meet stakeholders\' needs, notably in the Mediterranean region. This region has been identified as a climate change hot spot, and as a region where water demand is continuously increasing due to population growth and the expansion of irrigated areas. The Hérault River catchment (2500 km(2), France) is a typical example and a negative trend in discharge has been observed since the 1960s. In this context, local stakeholders need first to understand the processes controlling the evolution of water resources and demands in the past to latter evaluate future water supply capacity and anticipate the tensions users could be confronted to in the future. A modelling framework is proposed at a 10-day time step to assess whether water resources have been able to meet water demands over the last 50 years. Water supply was evaluated using hydrological modelling and a dam management model. Water demand dynamics were estimated for the domestic and agricultural sectors. A water supply capacity index is computed to assess the extent and the frequency to which water demand has been satisfied at the sub-basin scale. Simulated runoff dynamics were in good agreement with observations over the calibration and validation periods. Domestic water demand has increased considerably since the 1980s and is characterized by a seasonal peak in summer. Agricultural demand has increased in the downstream sub-basins and decreased upstream where irrigated areas have decreased. As a result, although most water demands were satisfied between 1961 and 1980, irrigation requirements in summer have sometimes not been satisfied since the 1980s. This work is the first step toward evaluating possible future changes in water allocation capacity in the catchment, using future climate change, dam management and water use scenarios.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Sci-hub)

公众号