旅行时间是交通的重要措施。准确的旅行时间预测也是操作和先进信息系统的基础。短期旅行时间预测等各种解决方案,例如利用实时GPS数据和优化方法来跟踪车辆的路径的解决方案。然而,可靠的长期预测仍然具有挑战性。我们在本文中展示了旅行时间的适用性和有用性即邮政服务的交货时间预测。我们调查了几种方法,如线性回归模型和基于树的集合,如随机森林,堆垛和升压,允许通过进行广泛的实验并考虑许多可用性方案来预测交货时间。结果表明,旅行时间预测可以帮助减轻邮政服务的高延误。我们表明,一些升压算法,例如轻梯度提升和CATBoost,在准确性和运行时效率方面具有比其他基线,如线性回归模型,装袋回归和随机林等其他基线具有更高的性能。
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The cyber-physical convergence is opening up new business opportunities for industrial operators. The need for deep integration of the cyber and the physical worlds establishes a rich business agenda towards consolidating new system and network engineering approaches. This revolution would not be possible without the rich and heterogeneous sources of data, as well as the ability of their intelligent exploitation, mainly due to the fact that data will serve as a fundamental resource to promote Industry 4.0. One of the most fruitful research and practice areas emerging from this data-rich, cyber-physical, smart factory environment is the data-driven process monitoring field, which applies machine learning methodologies to enable predictive maintenance applications. In this paper, we examine popular time series forecasting techniques as well as supervised machine learning algorithms in the applied context of Industry 4.0, by transforming and preprocessing the historical industrial dataset of a packing machine's operational state recordings (real data coming from the production line of a manufacturing plant from the food and beverage domain). In our methodology, we use only a single signal concerning the machine's operational status to make our predictions, without considering other operational variables or fault and warning signals, hence its characterization as ``agnostic''. In this respect, the results demonstrate that the adopted methods achieve a quite promising performance on three targeted use cases.
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最近,已经努力将信号阶段和时机(SPAT)消息标准化。这些消息包含所有信号交叉方法的信号相时机。因此,这些信息可用于有效的运动计划,从而导致更多均匀的交通流量和均匀的速度轮廓。尽管努力为半活化的信号控制系统提供了可靠的预测,但预测完全驱动控制的信号相时仍具有挑战性。本文提出了使用聚合的流量信号和循环检测器数据的时间序列预测框架。我们利用最先进的机器学习模型来预测未来信号阶段的持续时间。线性回归(LR),随机森林(RF)和长期内存(LSTM)神经网络的性能是针对天真基线模型进行评估的。结果基于瑞士苏黎世的全面信号控制系统的经验数据集表明,机器学习模型的表现优于常规预测方法。此外,基于树木的决策模型(例如RF)的表现最佳,其准确性满足实用应用要求。
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As ride-hailing services become increasingly popular, being able to accurately predict demand for such services can help operators efficiently allocate drivers to customers, and reduce idle time, improve congestion, and enhance the passenger experience. This paper proposes UberNet, a deep learning Convolutional Neural Network for short-term prediction of demand for ride-hailing services. UberNet empploys a multivariate framework that utilises a number of temporal and spatial features that have been found in the literature to explain demand for ride-hailing services. The proposed model includes two sub-networks that aim to encode the source series of various features and decode the predicting series, respectively. To assess the performance and effectiveness of UberNet, we use 9 months of Uber pickup data in 2014 and 28 spatial and temporal features from New York City. By comparing the performance of UberNet with several other approaches, we show that the prediction quality of the model is highly competitive. Further, Ubernet's prediction performance is better when using economic, social and built environment features. This suggests that Ubernet is more naturally suited to including complex motivators in making real-time passenger demand predictions for ride-hailing services.
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在线旅行社(OTA)的网站在元搜索竞标引擎上宣传。预测酒店将收到的单击数量的给定出价金额的问题是管理元搜索引擎上OTA广告活动的重要一步,因为出价时间的点击次数定义了要生成的成本。在这项工作中,各种回归器都结束了,以提高点击预测性能。按照预处理程序,将功能集分为火车和测试组,具体取决于样品的记录日期。然后,将数据收集进行基于XGBoost的缩小降低,从而大大降低了特征的维度。然后通过将贝叶斯高参数优化应用于XGBoost,LightGBM和SGD模型来找到最佳的高参数。单独测试了十种不同的机器学习模型,并将它们组合在一起以创建合奏模型。提出了三种替代合奏解决方案。相同的测试集用于测试单个和集合模型,46个模型组合的结果表明,堆栈集合模型得出所有的R2分数。总之,整体模型将预测性能提高了约10%。
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天然气管道中的泄漏检测是石油和天然气行业的一个重要且持续的问题。这尤其重要,因为管道是运输天然气的最常见方法。这项研究旨在研究数据驱动的智能模型使用基本操作参数检测天然气管道的小泄漏的能力,然后使用现有的性能指标比较智能模型。该项目应用观察者设计技术,使用回归分类层次模型来检测天然气管道中的泄漏,其中智能模型充当回归器,并且修改后的逻辑回归模型充当分类器。该项目使用四个星期的管道数据流研究了五个智能模型(梯度提升,决策树,随机森林,支持向量机和人工神经网络)。结果表明,虽然支持向量机和人工神经网络比其他网络更好,但由于其内部复杂性和所使用的数据量,它们并未提供最佳的泄漏检测结果。随机森林和决策树模型是最敏感的,因为它们可以在大约2小时内检测到标称流量的0.1%的泄漏。所有智能模型在测试阶段中具有高可靠性,错误警报率为零。将所有智能模型泄漏检测的平均时间与文献中的实时短暂模型进行了比较。结果表明,智能模型在泄漏检测问题中的表现相对较好。该结果表明,可以与实时瞬态模型一起使用智能模型,以显着改善泄漏检测结果。
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This paper proposes a data and Machine Learning-based forecasting solution for the Telecommunications network-rollout planning problem. Milestone completion-time estimation is crucial to network-rollout planning; accurate estimates enable better crew utilisation and optimised cost of materials and logistics. Using historical data of milestone completion times, a model needs to incorporate domain knowledge, handle noise and yet be interpretable to project managers. This paper proposes partition-based regression models that incorporate data-driven statistical models within each partition, as a solution to the problem. Benchmarking experiments demonstrate that the proposed approach obtains competitive to better performance, at a small fraction of the model complexity of the best alternative approach based on Gradient Boosting. Experiments also demonstrate that the proposed approach is effective for both short and long-range forecasts. The proposed idea is applicable in any context requiring time-series regression with noisy and attributed data.
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多种统计和机器学习方法用于使用机器学习方法在特定道路上建模崩溃频率,通常具有更高的预测准确性。最近,包括堆叠在内的异质集合方法(HEM)已成为更准确和强大的智能技术,并且通常通过提供更可靠和准确的预测来解决模式识别问题。在这项研究中,我们将堆叠的关键下摆方法之一应用于城市和郊区动脉的五个车道段(5T)上的崩溃频率。将堆叠的预测性能与参数统计模型(泊松和负二项式)和三种最先进的机器学习技术(决策树,随机森林和梯度增强)进行了比较,每种技术都被称为基础学习者。通过采用最佳的体重方案通过堆叠结合单个基础学习者,由于规格和预测准确性的差异,各个基础学习者中有偏见的预测问题可以避免。从2013年到2017年收集并集成了包括崩溃,流量和道路清单在内的数据。数据分为培训,验证和测试数据集。统计模型的估计结果表明,除其他因素外,崩溃随着不同类型的车道的密度(每英里数)的增加而增加。各种模型的样本外预测的比较证实了堆叠优于所考虑的替代方法的优越性。从实际的角度来看,堆叠可以提高预测准确性(与仅使用具有特定规范的基本学习者相比)。当系统地应用时,堆叠可以帮助确定更合适的对策。
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血浆定义为物质的第四个状态,在高电场下可以在大气压下产生非热血浆。现在众所周知,血浆激活液体(PAL)的强和广谱抗菌作用。机器学习(ML)在医疗领域的可靠适用性也鼓励其在等离子体医学领域的应用。因此,在PALS上的ML应用可以提出一种新的观点,以更好地了解各种参数对其抗菌作用的影响。在本文中,通过使用先前获得的数据来定性预测PAL的体外抗菌活性,从而介绍了比较监督的ML模型。进行了文献搜索,并从33个相关文章中收集了数据。在所需的预处理步骤之后,将两种监督的ML方法(即分类和回归)应用于数据以获得微生物灭活(MI)预测。对于分类,MI分为四类,对于回归,MI被用作连续变量。为分类和回归模型进行了两种不同的可靠交叉验证策略,以评估所提出的方法。重复分层的K折交叉验证和K折交叉验证。我们还研究了不同特征对模型的影响。结果表明,高参数优化的随机森林分类器(ORFC)和随机森林回归者(ORFR)分别比其他模型进行了分类和回归的模型更好。最后,获得ORFC的最佳测试精度为82.68%,ORFR的R2为0.75。 ML技术可能有助于更好地理解在所需的抗菌作用中具有主要作用的血浆参数。此外,此类发现可能有助于将来的血浆剂量定义。
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A well-performing prediction model is vital for a recommendation system suggesting actions for energy-efficient consumer behavior. However, reliable and accurate predictions depend on informative features and a suitable model design to perform well and robustly across different households and appliances. Moreover, customers' unjustifiably high expectations of accurate predictions may discourage them from using the system in the long term. In this paper, we design a three-step forecasting framework to assess predictability, engineering features, and deep learning architectures to forecast 24 hourly load values. First, our predictability analysis provides a tool for expectation management to cushion customers' anticipations. Second, we design several new weather-, time- and appliance-related parameters for the modeling procedure and test their contribution to the model's prediction performance. Third, we examine six deep learning techniques and compare them to tree- and support vector regression benchmarks. We develop a robust and accurate model for the appliance-level load prediction based on four datasets from four different regions (US, UK, Austria, and Canada) with an equal set of appliances. The empirical results show that cyclical encoding of time features and weather indicators alongside a long-short term memory (LSTM) model offer the optimal performance.
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在带有电动车队的乘车系统中,充电是一个复杂的决策过程。大多数电动汽车(EV)出租车服务要求驾驶员做出利己主义决定,从而导致分散的临时充电策略。车辆之间通常缺乏或不共享移动性系统的当前状态,因此无法做出最佳的决定。大多数现有方法都不将时间,位置和持续时间结合到全面的控制算法中,也不适合实时操作。因此,我们提出了一种实时预测性充电方法,用于使用一个名为“闲置时间开发(ITX)”的单个操作员进行乘车服务,该方法预测了车辆闲置并利用这些时期来收获能量的时期。它依靠图形卷积网络和线性分配算法来设计最佳的车辆和充电站配对,以最大程度地提高利用的空闲时间。我们通过对纽约市现实世界数据集的广泛模拟研究评估了我们的方法。结果表明,就货币奖励功能而言,ITX的表现优于所有基线方法至少提高5%(相当于6,000个车辆操作的$ 70,000),该奖励奖励功能的建模旨在复制现实世界中乘车系统的盈利能力。此外,与基线方法相比,ITX可以将延迟至少减少4.68%,并且通常通过促进顾客在整个车队中更好地传播乘客的舒适度。我们的结果还表明,ITX使车辆能够在白天收获能量,稳定电池水平,并增加需求意外激增的弹性。最后,与表现最佳的基线策略相比,峰值负载减少了17.39%,这使网格操作员受益,并为更可持续的电网使用铺平了道路。
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在人工智能中,我们经常寻求确定许多变量的未知目标函数$ y = f(\ mathbf {x})$给出有限的例子$ s = \ {(\ mathbf {x ^ {(i)}} ,y ^ {(i)})\} $ with $ \ mathbf {x ^ {(i)}} \以$ d $是一个感兴趣的域名。我们将$ S $称为培训集和最终任务是识别近似于新$ \ MATHBF {x} $近似于此目标函数的数学模型;使用$ t \ neq s $(即,测试模型泛化),设置$ t = \ {\ mathbf {x ^ {x ^ {x ^ {x ^ {x ^ {x ^ {x ^ {x ^ {x ^ {x但是,对于某些应用,主要兴趣是近似于较大的域名$ d'$的未知函数,该域为$ d $。例如,在涉及设计新结构的情况下,我们可能有兴趣最大化$ F $;因此,源自$ S $的模型也应该在$ d'$以$ y $大于$ s $ m $的值概括为$ d'$。从这种意义上讲,AI系统将提供重要信息,可以指导设计过程,例如,使用学习模型作为设计新实验室实验的代理功能。通过结合添加剂样条模型,我们基于持续分数的迭代配合来介绍一种多变量回归的方法。我们将其与Adaboost,内核,线性回归,Lasso Lars,线性支持向量回归,多层感知,随机林,随机梯度下降和XGBoost等方法进行比较。我们基于物理化学特性预测超导体临界温度的重要问题的性能。
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Platelet products are both expensive and have very short shelf lives. As usage rates for platelets are highly variable, the effective management of platelet demand and supply is very important yet challenging. The primary goal of this paper is to present an efficient forecasting model for platelet demand at Canadian Blood Services (CBS). To accomplish this goal, four different demand forecasting methods, ARIMA (Auto Regressive Moving Average), Prophet, lasso regression (least absolute shrinkage and selection operator) and LSTM (Long Short-Term Memory) networks are utilized and evaluated. We use a large clinical dataset for a centralized blood distribution centre for four hospitals in Hamilton, Ontario, spanning from 2010 to 2018 and consisting of daily platelet transfusions along with information such as the product specifications, the recipients' characteristics, and the recipients' laboratory test results. This study is the first to utilize different methods from statistical time series models to data-driven regression and a machine learning technique for platelet transfusion using clinical predictors and with different amounts of data. We find that the multivariate approaches have the highest accuracy in general, however, if sufficient data are available, a simpler time series approach such as ARIMA appears to be sufficient. We also comment on the approach to choose clinical indicators (inputs) for the multivariate models.
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提出了一种使用天气数据实时太阳生成预测的新方法,同时提出了既有空间结构依赖性的依赖。随着时间的推移,观察到的网络被预测到较低维度的表示,在该表示的情况下,在推理阶段使用天气预报时,使用各种天气测量来训练结构化回归模型。从国家太阳辐射数据库获得的德克萨斯州圣安东尼奥地区的288个地点进行了实验。该模型预测具有良好精度的太阳辐照度(夏季R2 0.91,冬季为0.85,全球模型为0.89)。随机森林回归者获得了最佳准确性。进行了多个实验来表征缺失数据的影响和不同的时间范围的影响,这些范围提供了证据表明,新算法不仅在随机的情况下,而且在机制是空间和时间上都丢失的数据是可靠的。
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本文比较分析随机森林的性能和基于历史数据预测能源消耗的领域的梯度增强算法的性能。应用两种算法以单独预测能源消耗,然后使用加权平均合奏方法合并在一起。所达到的实验结果之间的比较证明,加权平均合奏方法比单独应用的两种算法中的每种都提供了更准确的结果。
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合奏的基本分支混合合奏在许多机器学习问题,尤其是回归中蓬勃发展。几项研究证实了多样性的重要性。但是,以前的合奏仅考虑在子模型训练阶段的多样性,与单个模型相比,改进有限。相反,本研究从异质模型池中选择和权重子模型。它使用内点过滤线性搜索算法解决了优化问题。这种优化问题创新地将负相关学习作为惩罚项,可以选择多种模型子集。实验结果显示了一些有意义的观点。模型池构造需要不同类别的模型,每个类别都作为子模型为所有可能的参数集。选择每个类的最佳子模型以构建基于NCL的合奏,该集合比子模型的平均值要好得多。此外,与经典常数和非恒定加权方法相比,基于NCL的合奏在几种预测指标中具有重要优势。实际上,由于模型不确定性,很难在事先结论数据集的最佳子模型。但是,我们的方法将获得可比较的精度作为RMSE度量的潜在最佳子模型。总之,这项研究的价值在于它的易用性和有效性,使混合团合奏可以接受多样性和准确性。
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PV power forecasting models are predominantly based on machine learning algorithms which do not provide any insight into or explanation about their predictions (black boxes). Therefore, their direct implementation in environments where transparency is required, and the trust associated with their predictions may be questioned. To this end, we propose a two stage probabilistic forecasting framework able to generate highly accurate, reliable, and sharp forecasts yet offering full transparency on both the point forecasts and the prediction intervals (PIs). In the first stage, we exploit natural gradient boosting (NGBoost) for yielding probabilistic forecasts, while in the second stage, we calculate the Shapley additive explanation (SHAP) values in order to fully comprehend why a prediction was made. To highlight the performance and the applicability of the proposed framework, real data from two PV parks located in Southern Germany are employed. Comparative results with two state-of-the-art algorithms, namely Gaussian process and lower upper bound estimation, manifest a significant increase in the point forecast accuracy and in the overall probabilistic performance. Most importantly, a detailed analysis of the model's complex nonlinear relationships and interaction effects between the various features is presented. This allows interpreting the model, identifying some learned physical properties, explaining individual predictions, reducing the computational requirements for the training without jeopardizing the model accuracy, detecting possible bugs, and gaining trust in the model. Finally, we conclude that the model was able to develop complex nonlinear relationships which follow known physical properties as well as human logic and intuition.
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AI和数据驱动的解决方案已应用于不同的领域,并实现了优于和有希望的结果。在这项研究工作中,我们应用了K-Neart最邻居,极端的梯度提升和随机森林分类器来检测三个加密货币市场的趋势问题。我们使用这些分类器来设计一种在这些市场中进行交易的策略。我们在实验中的输入数据包括在单独的测试中使用或没有技术指标的价格数据,以查看使用它们的效果。我们对看不见数据的测试结果非常有前途,并在帮助具有专家系统的投资者利用市场并获利的投资者方面具有巨大的潜力。我们看不见的66天跨度的最高利润因子是1.60。我们还讨论了这些方法的局限性及其对有效市场假设的潜在影响。
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操作网络通常依靠机器学习模型来进行许多任务,包括检测异常,推断应用程序性能和预测需求。然而,不幸的是,模型精度会因概念漂移而降低,从而,由于从软件升级到季节性到用户行为的变化,功能和目标预测之间的关系会发生变化。因此,缓解概念漂移是操作机器学习模型的重要组成部分,尽管它很重要,但在网络或一般的回归模型的背景下,概念漂移并未得到广泛的探索。因此,对于当前依赖机器学习模型的许多常见网络管理任务,如何检测或减轻它并不是一件好事。不幸的是,正如我们所展示的那样,通过使用新可用的数据经常重新培训模型可以充分缓解概念漂移,甚至可以进一步降低模型的准确性。在本文中,我们表征了美国主要大都市地区的大型蜂窝网络中的概念漂移。我们发现,概念漂移发生在许多重要的关键性能指标(KPI)上,独立于模型,训练集大小和时间间隔,因此需要采用实用方法来检测,解释和减轻它。为此,我们开发了特征(叶)的局部误差近似。叶检测到漂移;解释最有助于漂移的功能和时间间隔;并使用遗忘和过度采样来减轻漂移。我们使用超过四年的蜂窝KPI数据来评估叶子与行业标准的缓解方法。在美国,我们对主要的细胞提供商进行的初步测试表明,LEAF在各种KPI和模型上都是有效的。叶子始终优于周期性,并触发重新培训,同时还要降低昂贵的重新经营操作。
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预测经济的短期动态 - 对经济代理商决策过程的重要意见 - 经常在线性模型中使用滞后指标。这通常在正常时期就足够了,但在危机期间可能不足。本文旨在证明,在非线性机器学习方法的帮助下,非传统和及时的数据(例如零售和批发付款)可以为决策者提供复杂的模型,以准确地估算几乎实时的关键宏观经济指标。此外,我们提供了一组计量经济学工具,以减轻机器学习模型中的过度拟合和解释性挑战,以提高其政策使用的有效性。我们的模型具有付款数据,非线性方法和量身定制的交叉验证方法,有助于提高宏观经济的启示准确性高达40 \% - 在COVID-19期间的增长较高。我们观察到,付款数据对经济预测的贡献很小,在低和正常增长期间是线性的。但是,在强年或正增长期间,付款数据的贡献很大,不对称和非线性。
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