Sampling

取样
  • 文章类型: Journal Article
    背景:人群病毒载量(VL),艾滋病毒传播潜力的最全面的衡量标准,由于缺乏对所有艾滋病毒感染者的完整抽样,因此无法直接测量。
    目标:给定HIV诊所的电子健康记录(EHR),这个群体的一个有偏见的样本,可能被用来试图推算这一措施。
    方法:我们模拟了一个由10,000名个体组成的群体,并根据几何平均值为4449拷贝/mL的监测数据进行了VL校准。我们从(A)源种群中采样了3个假设的EHR,(B)那些被诊断的人,和(C)那些被保留在照管中的人。我们的分析使用抽样权重,然后进行贝叶斯调整,从每个EHR估算出人口VL。然后使用来自特拉华州HIV诊所的EHR数据来测试这些方法。
    结果:加权后,估计值以相应更宽的95%间隔向人群值的方向移动,如下:诊所A:4364(95%间隔1963-11,132)拷贝/mL;诊所B:4420(95%间隔1913-10,199)拷贝/mL;诊所C:242(95%间隔113-563)拷贝/mL.贝叶斯调整的加权进一步改进了估计。
    结论:这些发现表明,方法学调整对于从单个诊所的EHR估计群体VL是无效的,而没有资源密集型的信息先验的阐明。
    BACKGROUND: Population viral load (VL), the most comprehensive measure of the HIV transmission potential, cannot be directly measured due to lack of complete sampling of all people with HIV.
    OBJECTIVE: A given HIV clinic\'s electronic health record (EHR), a biased sample of this population, may be used to attempt to impute this measure.
    METHODS: We simulated a population of 10,000 individuals with VL calibrated to surveillance data with a geometric mean of 4449 copies/mL. We sampled 3 hypothetical EHRs from (A) the source population, (B) those diagnosed, and (C) those retained in care. Our analysis imputed population VL from each EHR using sampling weights followed by Bayesian adjustment. These methods were then tested using EHR data from an HIV clinic in Delaware.
    RESULTS: Following weighting, the estimates moved in the direction of the population value with correspondingly wider 95% intervals as follows: clinic A: 4364 (95% interval 1963-11,132) copies/mL; clinic B: 4420 (95% interval 1913-10,199) copies/mL; and clinic C: 242 (95% interval 113-563) copies/mL. Bayesian-adjusted weighting further improved the estimate.
    CONCLUSIONS: These findings suggest that methodological adjustments are ineffective for estimating population VL from a single clinic\'s EHR without the resource-intensive elucidation of an informative prior.
    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
    背景:教育神经科学研究,研究学习的神经生物学机制,历史上纳入了主要来自白色的样本,中产阶级,和/或郊区人口。然而,在不关注代表性的研究中进行抽样可能会导致有偏见的解释和结果,这些结果不太容易推广到预期的目标人群。先前的研究揭示了群体内和跨群体的神经认知结果的差异,进一步表明,这种做法可能会掩盖具有实际意义的重大影响。
    历史边缘化社区的消极态度,源于历史虐待,有偏见的研究结果,以及研究团队之间隐含或明确的态度,会阻碍多元化参与。研究过程的质量,包括语言要求,研究地点,时间需求会产生额外的障碍。
    方法:灵活的数据收集方法,社区扩张,透明的报告可以建立信任并增强抽样多样性。长期解决方案包括优先考虑与边缘化社区相关的研究问题,增加劳动力多样性,以及样本人口统计数据的详细报告。这种共同努力对于强大的教育神经科学研究至关重要,以最大程度地扩大学习者的积极影响。
    BACKGROUND: Educational neuroscience research, which investigates the neurobiological mechanisms of learning, has historically incorporated samples drawn mostly from white, middle-class, and/or suburban populations. However, sampling in research without attending to representation can lead to biased interpretations and results that are less generalizable to an intended target population. Prior research revealing differences in neurocognitive outcomes both within- and across-groups further suggests that such practices may obscure significant effects with practical implications.
    UNASSIGNED: Negative attitudes among historically marginalized communities, stemming from historical mistreatment, biased research outcomes, and implicit or explicit attitudes among research teams, can hinder diverse participation. Qualities of the research process including language requirements, study locations, and time demands create additional barriers.
    METHODS: Flexible data collection approaches, community engaugement, and transparent reporting could build trust and enhance sampling diversity. Longer-term solutions include prioritizing research questions relevant to marginalized communities, increasing workforce diversity, and detailed reporting of sample demographics. Such concerted efforts are essential for robust educational neuroscience research to maximize positive impacts broadly across learners.
    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
    背景:在为患者偏好研究选择样本时,招募符合特定治疗决定条件的参与者可能很困难或不切实际.然而,一般公众样本可能不是合适的代理人。
    目的:本研究比较了普通公众成员和确诊RA患者的一级亲属(FDRs)对类风湿关节炎(RA)预防性治疗的偏好,以评估普通公众样本是否可以用作FDRs的代表。
    方法:参与者被要求想象他们正在经历关节痛,并进行筛查测试,表明在2年内有60%的机会发展为RA。使用离散选择实验,参与者在不接受治疗和2种未标记的假设治疗之间进行了一系列选择,以降低RA的风险.为了评估数据质量,完成调查部分的时间和理解问题进行了评估。使用随机参数Logit模型来获得属性级估计,用于计算相对重要性,最大可接受风险(MAR),以及假设的预防性治疗的市场份额。
    结果:与一般公众样本(n=982)相比,FDR样本(n=298)花费了更多的时间完成调查,并且在理解问题上表现更好。一般公众和FDR参与者样本之间的相对重要性排名相似;然而,其他涉及权重的相对偏好度量,包括MAR和市场份额,FDR的MARs数值较高。
    结论:在RA预防方面,一般公众(平均风险)可能是总体相对重要性排名而不是权重的风险更大的样本(FDRs)的合理代理。代理样本的理由应该是明确的。
    结论:使用离散选择实验,将来自普通公众的参与者与一级亲属对类风湿关节炎(RA)预防性治疗的偏好进行比较。就预防性治疗的最重要和最不重要的属性而言,组间的偏好相似,效率是最重要的属性。然而,相对权重不同。公众和一级亲属对假设的RA预防性治疗的调查和预测的市场份额有所不同。公众可能是患者偏好等级的风险群体的合理代表,但不是疾病预防背景下的权重;然而,在选择非患者时,在进行患者偏好研究的样本选择时应格外小心.
    BACKGROUND: When selecting samples for patient preference studies, it may be difficult or impractical to recruit participants who are eligible for a particular treatment decision. However, a general public sample may not be an appropriate proxy.
    OBJECTIVE: This study compares preferences for rheumatoid arthritis (RA) preventive treatments between members of the general public and first-degree relatives (FDRs) of confirmed RA patients to assess whether a sample of the general public can be used as a proxy for FDRs.
    METHODS: Participants were asked to imagine they were experiencing arthralgia and had screening tests indicating a 60% chance of developing RA within 2 yrs. Using a discrete choice experiment, participants were offered a series of choices between no treatment and 2 unlabeled hypothetical treatments to reduce the risk of RA. To assess data quality, time to complete survey sections and comprehension questions were assessed. A random parameter logit model was used to obtain attribute-level estimates, which were used to calculate relative importance, maximum acceptable risk (MAR), and market shares of hypothetical preventive treatments.
    RESULTS: The FDR sample (n = 298) spent more time completing the survey and performed better on comprehension questions compared with the general public sample (n = 982). The relative importance ranking was similar between the general public and FDR participant samples; however, other relative preference measures involving weights including MARs and market share differed between groups, with FDRs having numerically higher MARs.
    CONCLUSIONS: In the context of RA prevention, the general public (average risk) may be a reasonable proxy for a more at-risk sample (FDRs) for overall relative importance ranking but not weights. The rationale for a proxy sample should be clearly justified.
    CONCLUSIONS: Participants from the general public were compared to first-degree relatives on their preferences for rheumatoid arthritis (RA) preventive treatments using a discrete choice experiment.Preferences were similar between groups in terms of the most important and least important attributes of preventive treatments, with effectiveness being the most important attribute. However, relative weights differed.Attention to the survey and predicted market shares of hypothetical RA preventive treatments differed between the general public and first-degree relatives.The general public may be a reasonable proxy for an at-risk group for patient preferences ranks but not weights in the disease prevention context; however, care should be taken in sample selection for patient preference studies when choosing nonpatients.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: English Abstract
    An overview of researches, mainly by foreign specialists, on current available approaches for sampling to study the traces of gunshot residue (GSR) is presented. The comparative characteristics of traditional methods of samples (use of cotton and gauze tampons, blotting paper, textile fabrics, adhesive tapes, adhesives and vacuum samplers), as well as advanced technologies, including special devices and sorbents, are given. The characteristics of samplings from hands, scalp, nostrils, clothes of examined persons as well as procedures, that allow to increase the duration of GSR detection, are described in details. The importance of GSR sustainability over time is noted. On average, the most likely detection periods of particles are less than 1 hour for samples, collected from hands, more than 1 hour for samples from clothes and 2-3 hours for face. It is possible to detect the GSR particles in hair up to 24 h., and in nasal mucus after 6 h. of shot. The methods of identification and determination for analytes of inorganic and organic nature are discussed. The most common methods for determining heavy metal particles are atomic spectrometry, namely atomic absorption with electrothermal atomization and atomic emission. The combination of scanning laser ablation and mass-spectrometry with inductively coupled plasma makes it possible to detect more than 15 analytes in a single sample. Scanning electron microscopy with X-ray detectors is effective for the examination of powder particles. The described methods of sampling complement each other increasing the possibility of evidence base for court proceedings.
    Представлен обзор научных работ, в основном зарубежных специалистов, по имеющимся на данный момент способам отбора проб для исследования следов продуктов выстрела (СПВ). Приведены сравнительные характеристики традиционных способов (использование ватных и марлевых тампонов, фильтровальной бумаги, текстильной ткани, липких лент, клеев, вакуумных пробоотборников) пробоотбора, а также передовых технологий, включая специальные устройства и сорбенты. Подробно описаны особенности отбора проб на руках, волосистой части головы, ноздрях, одежде проверяемых лиц, а также соответствующие процедуры, позволяющие повысить длительность периода обнаружения СПВ. Отмечена важность фактора устойчивости СПВ во времени. В среднем периоды наиболее вероятного обнаружения частиц составляют <1 ч для образцов, изъятых с рук, >1 ч для одежды и около 2—3 ч для лица. Обнаружение частиц СПВ на волосах возможно до 24 ч, а в носовой слизи — через 6 ч после выстрела. Обсуждаются методы идентификации и определения аналитов неорганической и органической природы. Для определения частиц тяжелых металлов наиболее распространены методы атомной спектрометрии: атомно-абсорбционный с электротермической атомизацией и атомно-эмиссионный. Комбинация сканирующей лазерной абляции и масс-спектрометрии с индуктивно связанной плазмой позволяет определять свыше 15 аналитов в одной пробе. Для исследования пороховых частиц эффективно использование сканирующей электронной микроскопии с рентгеновскими детекторами. Описанные способы отбора проб дополняют друг друга, увеличивая возможность доказательной базы для судебного производства.
    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
    这项研究检查了训练(进入俱乐部时的年龄,小时的俱乐部练习,自由发挥,其他运动)和环境特征(受欢迎程度,媒体报道,学校和父母的支持)在三个十年的时间里影响了瑞士国家队女运动员在精英足球中的发展。
    84名参与者完成了回顾性调查问卷,根据与瑞士国家队的第一场比赛,他们被分为三个队列(C1=2000年,n=24;C2=2001-2010年,n=29;C3=2011-2022年,n=31)。采用方差分析来比较关于训练和环境变量的队列。
    研究结果表明,感知到的环境条件更好,童年自由游戏和其他运动的数量停滞不前,降低俱乐部进入的年龄,并增加各队列的俱乐部实践和总训练量。
    实际含义突出了空闲时间和俱乐部实践的微观结构中的非结构化环境中的人才发展途径。
    UNASSIGNED: This study examines the training (age at club entry, hours in club practice, free play, other sports) and environmental characteristics (popularity, media coverage, school and parental support) influencing the development of female Swiss national team players in elite football over a three-decade period.
    UNASSIGNED: A retrospective questionnaire was completed by 84 participants, who were divided into three cohorts based on their first game with the Swiss national team (C1 = until 2000, n = 24; C2 = 2001-2010, n = 29; C3 = 2011-2022, n = 31). ANOVAs were employed to compare the cohorts regarding training and environmental variables.
    UNASSIGNED: The findings demonstrate better perceived environmental conditions, stagnating volume of free play and other sports in childhood, decreasing age at club entry, and increasing club practice and total training volume across cohorts.
    UNASSIGNED: Practical implications highlight talent development avenues in unstructured settings during free time and in the micro-structure of club practice.
    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
    严重急性呼吸道综合症冠状病毒2(SARS-CoV-2)可以在上下呼吸道复制。我们旨在评估采样前的症状特征和症状持续时间是否与上或下呼吸道样本的测试阳性相关。
    我们于2020年4月14日至2020年11月2日在丹麦中部地区进行了一项回顾性队列研究,包括在48小时内来自上呼吸道和下呼吸道的SARS-CoV-2逆转录酶聚合酶链反应样本的住院患者以及至少一个阳性测试结果。
    在122名患者中,101在两个样本中(83%)均为阳性,7(5%)仅在上呼吸道样本中呈阳性,和14(11%)仅在下呼吸道样本中呈阳性。症状的中位数为4(IQR3,5.75)和5(IQR3,7),分别,仅上呼吸道样本阳性的患者和一致阳性的患者;而仅上呼吸道样本阳性的患者为1(IQR1,3)。如果下呼吸道的补充取样以下呼吸道症状为指导,98%(120/122)的患者将被诊断为2019年冠状病毒病。在三个患者组中没有观察到症状持续时间的实质性差异。
    下呼吸道症状的存在可用于确定是否需要从下呼吸道进行补充采样。症状持续时间与上呼吸道或下呼吸道的测试阳性无关。
    Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can replicate in the upper and lower respiratory tract. We aimed to evaluate whether symptom characteristics and symptom duration prior to sampling are associated with test positivity in upper or lower respiratory tract samples.
    We conducted a retrospective cohort study in the Central Denmark Region from 14 April 2020 to 2 November 2020 including hospitalised patients with SARS-CoV-2 reverse transcriptase-polymerase chain reaction samples from both the upper and lower respiratory tract within 48 h and at least one positive test result.
    Of 122 patients, 101 were positive in both samples (83%), 7 (5%) were positive only in the upper respiratory tract sample, and 14 (11%) were only positive in the lower respiratory tract sample. The median number of symptoms was 4 (IQR 3, 5.75) and 5 (IQR 3, 7), respectively, in patients with only a positive upper respiratory tract sample and in concordant positive patients; while 1 (IQR 1, 3) in patients with only a positive upper respiratory tract sample. 98% (120/122) of patients would have been diagnosed with coronavirus disease 2019 if supplemental sampling from the lower respiratory tract was guided by lower respiratory tract symptoms. No substantial difference in the duration of symptoms was observed across the three patient groups.
    The presence of lower respiratory tract symptoms could have been used to determine whether supplemental sampling from the lower respiratory tract was necessary. Symptom duration was not associated with test positivity in the upper or lower respiratory tract.
    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
    生态瞬时评估(EMA)广泛用于健康研究,以捕获个人在日常生活中的经验。大多数EMA研究,然而,依靠非概率抽样方法,在EMA研究中留下了非随机参与感兴趣的个体特征的可能性。需要了解预测参与EMA研究的因素,以评估这种可能性,并且还可以告知最佳招聘策略。
    本研究旨在研究愿意参与EMA研究与受访者特征相关的程度,并确定参与的最关键预测因素。
    我们利用了有关潜在EMA参与者的一般年轻成年人群的全面数据的可用性,并使用和比较了逻辑回归,分类和回归树,和随机森林方法来评估受访者参与几十年到几分钟EMA研究的特征预测因子。
    在未调整的逻辑回归模型中,性别,迁移背景,焦虑,注意缺陷多动障碍的症状,压力,和亲社会性是参与意愿的重要预测因子;在Logistic回归模型中,为所有预测因子相互调整,迁移背景,烟草使用,社会排斥是重要的预测因素。基于树的方法还确定了迁移状态,烟草使用,和亲社会是突出的预测因素。然而,总的来说,从受访者的特征来看,参与数十年至分钟EMA研究的意愿只能弱地预测。最佳模型的曲线下交叉验证面积仅在0.56至0.57的范围内。
    结果表明,迁移背景是改善EMA参与和样本代表性的唯一最有希望的目标;然而,需要更多的研究来改善对健康EMA研究参与的预测。
    Ecological momentary assessment (EMA) is widely used in health research to capture individuals\' experiences in the flow of daily life. The majority of EMA studies, however, rely on nonprobability sampling approaches, leaving open the possibility of nonrandom participation concerning the individual characteristics of interest in EMA research. Knowledge of the factors that predict participation in EMA research is required to evaluate this possibility and can also inform optimal recruitment strategies.
    This study aimed to examine the extent to which being willing to participate in EMA research is related to respondent characteristics and to identify the most critical predictors of participation.
    We leveraged the availability of comprehensive data on a general young adult population pool of potential EMA participants and used and compared logistic regression, classification and regression trees, and random forest approaches to evaluate respondents\' characteristic predictors of willingness to participate in the Decades-to-Minutes EMA study.
    In unadjusted logistic regression models, gender, migration background, anxiety, attention deficit hyperactivity disorder symptoms, stress, and prosociality were significant predictors of participation willingness; in logistic regression models, mutually adjusting for all predictors, migration background, tobacco use, and social exclusion were significant predictors. Tree-based approaches also identified migration status, tobacco use, and prosociality as prominent predictors. However, overall, willingness to participate in the Decades-to-Minutes EMA study was only weakly predictable from respondent characteristics. Cross-validation areas under the curve for the best models were only in the range of 0.56 to 0.57.
    Results suggest that migration background is the single most promising target for improving EMA participation and sample representativeness; however, more research is needed to improve prediction of participation in EMA studies in health.
    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
    在案例交叉研究中,评估三种对照抽样策略的暴露-结果效应估计的偏差和精度。
    在线病例交叉研究调查了膝骨关节炎急性耀斑的八种与体力活动相关的触发因素。在危险期(自我宣布的耀斑发作前≤24小时)测量暴露。控制期暴露量以三种方式进行测量:(1)在13周内进行四次预定问卷,(2)基线确定的“正常”身体活动水平,(3)耀斑发作前三天以上。衍生的赔率比,比较95%置信区间和标准误差。
    744名参与者(平均年龄62.1[SD10.2]岁;61%为女性),493报告了714次耀斑。从预定问卷中选择控件,独立于危险时期,在预期方向上产生了主要的赔率比(曝光“很多”与曝光“根本没有”,范围:0.57-3.22)。当在基线(范围:0.01-1.42)或紧接爆发前(范围:0.30-1.27)对对照进行采样时,大多数比值比估计值被颠倒。与在基线(范围:0.267-0.589)或紧接爆发前(范围:0.319-0.621)采样的对照相比,从计划问卷(范围:0.264-0.473)中采样的对照时,对数比值比的标准误差最小。
    我们的发现对对照样品选择很敏感。在一定条件下,不同的模式可以归因于过度报道和社会可取性偏见,人们可能想更积极地展示自己的“日常”身体活动水平,在基线。在耀斑时的曝光测量可能不太精确,并且由于在耀斑期间系统地报告不同的曝光,因此更容易受到召回偏差的影响。与独立于耀斑的控制测量相比。
    UNASSIGNED: To evaluate bias and precision of exposure-outcome effect estimates from three control sampling strategies in a case-crossover study.
    UNASSIGNED: Online case-crossover study investigating eight physical activity-related triggers for acute flares in knee osteoarthritis. Exposures were measured in hazard periods (≤24 hours before self-declared flare onset). Control period exposure was measured in three ways: (1) four scheduled questionnaires over 13-weeks, (2) \"usual\" physical activity levels ascertained at baseline, (3) over three days before flare onset. Derived odds ratios, 95% confidence intervals and standard errors were compared.
    UNASSIGNED: Of 744 participants (mean age 62.1 [SD 10.2] years; 61% female), 493 reported 714 flares. Selecting controls from scheduled questionnaires, independent of hazard periods, yielded predominantly odds ratios in the expected direction (exposure \"a lot\" versus exposure \"not at all\", range: 0.57-3.22). When controls were sampled at baseline (range: 0.01-1.42) or immediately before a flare (range: 0.30-1.27) most odds ratio estimates were inverted. Standard errors of the log odds ratios were smallest when controls were sampled from scheduled questionnaires (range: 0.264-0.473) compared to controls sampled at baseline (range: 0.267-0.589) or immediately before a flare (range: 0.319-0.621).
    UNASSIGNED: Our findings are sensitive to control sample selection. Under certain conditions, different patterns could be attributed to over reporting and social desirability bias, where people may want to present themselves more positively about their \"usual\" physical activity levels, at baseline. Exposure measurement at the time of a flare may be less precise and more susceptible to recall bias due to systematically reporting exposures differently during a flare, compared to control measurement independent of flares.
    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
    有关食品安全监控的历史数据通常用作设计监控计划的信息源。然而,这样的数据通常是不平衡的:数据集的一小部分涉及高浓度的食品安全危害(代表被污染的高风险的商品批次,阳性)和数据集的很大一部分是指低浓度存在的食品安全危害(代表受污染风险较低的商品批次,底片)。这种不平衡的数据集使建模复杂化,以预测商品批次的污染概率。本研究提出了一种加权贝叶斯网络(WBN)分类器,利用不平衡监测数据,提高存在食品和饲料安全隐患的模型预测精度,专门用于饲料中重金属的存在。应用不同的权重值导致每个相关类别的不同分类精度;最佳权重值被定义为产生最有效监测计划的值,也就是说,确定受污染饲料批次的最高百分比。结果表明,贝叶斯网络分类器导致阳性样本(20%)和阴性样本(99%)的分类精度之间存在较大差异。随着WBN的方法,阳性样本和阴性样本的分类准确率均在80%左右,对于预先设定的3000个样本量,监测有效性从31%增加到80%。本研究结果可用于提高食品和饲料中各种食品安全危害监测的有效性。
    Historical data on food safety monitoring often serve as an information source in designing monitoring plans. However, such data are often unbalanced: a small fraction of the dataset refers to food safety hazards that are present in high concentrations (representing commodity batches with a high risk of being contaminated, the positives) and a high fraction of the dataset refers to food safety hazards that are present in low concentrations (representing commodity batches with a low risk of being contaminated, the negatives). Such unbalanced datasets complicate modeling to predict the probability of contamination of commodity batches. This study proposes a weighted Bayesian network (WBN) classifier to improve the model prediction accuracy for the presence of food and feed safety hazards using unbalanced monitoring data, specifically for the presence of heavy metals in feed. Applying different weight values resulted in different classification accuracies for each involved class; the optimal weight value was defined as the value that yielded the most effective monitoring plan, that is, identifying the highest percentage of contaminated feed batches. Results showed that the Bayesian network classifier resulted in a large difference between the classification accuracy of positive samples (20%) and negative samples (99%). With the WBN approach, the classification accuracy of positive samples and negative samples were both around 80%, and the monitoring effectiveness increased from 31% to 80% for pre-set sample size of 3000. Results of this study can be used to improve the effectiveness of monitoring various food safety hazards in food and feed.
    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
    这项研究的范围包括建立一个综合的具有成本效益的采样和实验室分析程序,描述采样,细颗粒提取废物沉积物的二次采样和分析不确定性。此程序旨在为决策者提供支持,以促进细粒废物堆积物的回收和土地开垦。此过程包括平衡复制采样设计(BRSD)以及三个拆分水平ANOVA数据处理。本文为读者提供了三个分层ANOVA分析(3L-ANOVA)的数学背景以及其实现的Excel算法。此外,本文介绍了在罗马尼亚铁矿石尾矿(IOT)旧池塘的情况下实施所开发方法的示例。本文的研究结果包括:a)认为,基于OM,SEM-EDS,XRFS和XRD观察,经典TOS对细粒度废物沉积物无效;b)BRSD与3L-ANOVA分析相结合是唯一适合可靠表征细粒度库存的方法;c)采样不确定性是分析物浓度不确定性预算的关键因素;d)Lilliefors方法适用于被测量值是否正常分布的假设检验;e)进行的BRDSD和TeliOVA调查的结果估计约5.5*106立方米,主要包括批次水平的矿物定量,即石英54%(±7%),赤铁矿15%(±3%),方解石11%(±3%),MgO3%(±1%),Al2O39%(±2%)。一些像Ti这样的CRM的浓度,V,Ba,Y,W在ACE极限及其相关的相对扩展不确定度超过50%。因此,扩大的不确定性清楚地描述了决策者关于废物价值的获取数据的可靠性。f)进入Teliuc的物联网可以作为水泥和陶瓷工业以及地质聚合物制造的矿物进行循环。此外,物联网可以作为道路建设和矿山封闭的填料。最后,Teliuc堆场可以在零浪费的情况下进行修复。通过增加收集项目的数量,可以将此程序提供的数据准确性提高到任何期望的水平。但是采样和分析的成本成比例地增加。在这种情况下,可以根据利益相关者的要求对发布的方法进行定制,以安全地支持将细粒度的副产品转化为有价值的二次资源的决定,促进采矿业更大的循环性。
    The scope of this study consists of setting up of an integrated cost-effective sampling & laboratory analyses procedure which delineates sampling, sub-sampling and analytical uncertainties in case of fine-grained extractive waste deposits. This procedure is designed to support the decision makers towards fine-grained waste deposits upcycling and land reclamation. This procedure consists of a balanced replicated sampling design (BRSD) coupled with a three split levels ANOVA data processing. The paper provides the readership with the mathematical backgrounds of the three split level ANOVA analysis (3L-ANOVA) and an Excel algorithm for its implementation. Also, the paper presents an example of implementation of the developed methods in the case of a Romanian iron ore tailings (IOT) old pond. The findings of the paper consist of: a) argues, based on OM, SEM-EDS, XRFS and XRD observations, that classical TOS is ineffective for fine-grained waste deposits; b) BRSD in conjunction with 3L-ANOVA analysis is the only approach fit for reliable characterization of the fine-grained stockpiles; c) sampling uncertainty is the critical factor of the uncertainty budget of the analyte concentration; d) Lilliefors approach is adequate for the hypothesis testing where or not the measurand is normal distributed; e) The outcomes of the BRDSD&3L-ANOVA investigations carried on Teliuc tailings, estimated at circa 5.5* 106 m3, consist mainly of mineral quantification at lot level i.e. quartz ∼54% (±7%), hematite ∼15% (±3%), calcite ∼11% (±3%), MgO 3% (±1%), Al2O3 9% (±2%). The concentrations of some CRMs like Ti, V, Ba, Y, W were found at ACE limits and their associated relative expanded uncertainties overpass 50%. Thus, the expanded uncertainties clearly depict the reliability of acquired data for the decision makers regarding waste valorization. f) The IOT into Teliuc can be upcycled as minerals for cement and ceramic industries as well as for geopolymer manufacture. Also, IOT can be downcycles as filler in road construction and mine closure. Finally, the Teliuc yard can be rehabilitated with zero-waste left behind. The data exactness provided by this procedure can be increased to any desirable level through increasing the number of collected items, but the cost of sampling and analyses increases proportionally. In such circumstances, the posted approach can be tailored at the stakeholder request as to safely underpin the decision to turn finegrained by-products into valuable secondary resources, facilitating a greater circularity of the mining industry.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

公众号