scholarly journals An Association Rules-Based Method for Outliers Cleaning of Measurement Data in the Distribution Network

2021 ◽  
Vol 9 ◽  
Author(s):  
Hua Kuang ◽  
Risheng Qin ◽  
Mi He ◽  
Xin He ◽  
Ruimin Duan ◽  
...  
Keyword(s):  
Cost Function ◽  
Association Rules ◽  
Mahalanobis Distance ◽  
Spatial Clustering ◽  
Distribution Network ◽  
Measurement Data ◽  
Operation Management ◽  
Test Results ◽  
Cleaning Method ◽  
Outliers Detection

For any power system, the reliability of measurement data is essential in operation, management and also in planning. However, it is inevitable that the measurement data are prone to outliers, which may impact the results of data-based applications. In order to improve the data quality, the outliers cleaning method for measurement data in the distribution network is studied in this paper. The method is based on a set of association rules (AR) that are automatically generated form historical measurement data. First, the association rules are mining in conjunction with the density-based spatial clustering of application with noise (DBSCAN), k-means and Apriori technique to detect outliers. Then, for the outliers repairing process after outliers detection, the proposed method uses a distance-based model to calculate the repairing cost of outliers, which describes the similarity between outlier and normal data. Besides, the Mahalanobis distance is employed in the repairing cost function to reduce the errors, which could implement precise outliers cleaning of measurement data in the distribution network. The test results for the simulated datasets with artificial errors verify that the superiority of the proposed outliers cleaning method for outliers detection and repairing.

scholarly journals Load characteristics of three-plunger pumps for spray seawater fire-fighting

2020 ◽  
pp. 142-146
Author(s):  
В.А. Наумов ◽  
Н.Л. Великанов ◽  
А.В. Тришина
Keyword(s):  
Satisfactory Agreement ◽  
Test Data ◽  
High Efficiency ◽  
Measurement Data ◽  
Fire Fighting ◽  
Test Results ◽  
Hydraulic Characteristics ◽  
Fire Extinguishing ◽  
Load Characteristics ◽  
Low Pressures

Цель статьи – получить эмпирические зависимости для характеристик трехплунжерных противопожарных насосов (ТПН), необходимые для автоматизации расчетов систем тушения пожаров на судах с применением распыленной морской воды. Задачи исследования: проверка непротиворечивости данных испытаний; определение расчетных зависимостей производительности ТПН, к.п.д., затраченной мощности от давления. Проведенный анализ результатов испытаний ТПН подтвердил возможность использования предложенных зависимостей в инженерных расчетах. Данные измерений удовлетворительно согласуются с результатами расчетов, за исключением к.п.д. Отклонение экспериментальных точек от эмпирических зависимостей, скорее всего, связано с занижением значений затраченной мощности на испытаниях при небольших давлениях. Предложено для оценки к.п.д. использовать ранее полученную типовую зависимость. Построены графики для характеристик насоса NP25/41-170S. Пример расчета рабочей точки насосной установки с использованием приближенной гидравлической характеристики водяной пожарной системы судна показал высокую эффективность предложенных методик. The purpose of the article is to obtain empirical dependences for the characteristics of three-plunger fire-fighting pumps (TFP), which are necessary for automating calculations of fire extinguishing systems on ships using sprayed seawater. Research objectives: checking the consistency of test data; determining the calculated dependences of the TFP performance, efficiency, power expended on pressure. The analysis of the TFP test results confirmed the possibility of using the proposed dependencies in engineering calculations. The measurement data are in satisfactory agreement with the results of calculations, with the exception of efficiency. The deviation of experimental points from the empirical dependences is most likely due to an underestimation of the power consumed during tests at low pressures. It is proposed to use the previously obtained typical dependence to estimate the efficiency. Graphs are plotted for the characteristics of the NP25/41-170S pump. An example of calculating the working point of a pumping unit using the approximate hydraulic characteristics of the ship's water fire system showed the high efficiency of the proposed methods.

scholarly journals Time interval measurement module implemented in SoC FPGA device

2016 ◽  
Vol 62 (3) ◽  
pp. 237-246 ◽  
Author(s):  
Grzegorz Grzęda ◽  
Ryszard Szplet
Keyword(s):  
Mass Measurement ◽  
Measurement Data ◽  
Measurement Instrument ◽  
General Concept ◽  
Time Interval ◽  
Processing Unit ◽  
Test Results ◽  
Interval Measurement ◽  
Time Interval Measurement ◽  
On Chip

Abstract We presents the design and test results of a picosecond-precision time interval measurement module, integrated as a System-on-Chip in an FPGA device. Implementing a complete measurement instrument of a high precision in one chip with the processing unit gives an opportunity to cut down the size of the final product and to lower its cost. Such approach challenges the constructor with several design issues, like reduction of voltage noise, propagating through power lines common for the instrument and processing unit, or establishing buses efficient enough to transport mass measurement data. The general concept of the system, design hierarchy, detailed hardware and software solutions are presented in this article. Also, system test results are depicted with comparison to traditional ways of building a measurement instrument.

scholarly journals An Adaptive Ellipse Distance Density Peak Fuzzy Clustering Algorithm Based on the Multi-target Traffic Radar

Sensors ◽  
2020 ◽  
Vol 20 (17) ◽  
pp. 4920
Author(s):  
Lin Cao ◽  
Xinyi Zhang ◽  
Tao Wang ◽  
Kangning Du ◽  
Chong Fu
Keyword(s):  
Euclidean Distance ◽  
Clustering Algorithm ◽  
Spatial Clustering ◽  
Search Algorithm ◽  
Measurement Data ◽  
Data Sets ◽  
Density Peak ◽  
Close Range ◽  
Decision Graph ◽  
Membership Matrix

In the multi-target traffic radar scene, the clustering accuracy between vehicles with close driving distance is relatively low. In response to this problem, this paper proposes a new clustering algorithm, namely an adaptive ellipse distance density peak fuzzy (AEDDPF) clustering algorithm. Firstly, the Euclidean distance is replaced by adaptive ellipse distance, which can more accurately describe the structure of data obtained by radar measurement vehicles. Secondly, the adaptive exponential function curve is introduced in the decision graph of the fast density peak search algorithm to accurately select the density peak point, and the initialization of the AEDDPF algorithm is completed. Finally, the membership matrix and the clustering center are calculated through successive iterations to obtain the clustering result.The time complexity of the AEDDPF algorithm is analyzed. Compared with the density-based spatial clustering of applications with noise (DBSCAN), k-means, fuzzy c-means (FCM), Gustafson-Kessel (GK), and adaptive Euclidean distance density peak fuzzy (Euclid-ADDPF) algorithms, the AEDDPF algorithm has higher clustering accuracy for real measurement data sets in certain scenarios. The experimental results also prove that the proposed algorithm has a better clustering effect in some close-range vehicle scene applications. The generalization ability of the proposed AEDDPF algorithm applied to other types of data is also analyzed.

3D automatic liver segmentation using feature-constrained Mahalanobis distance in CT images

2016 ◽  
Vol 61 (4) ◽  
pp. 401-412 ◽  
Author(s):  
Saif Dawood Salman Al-Shaikhli ◽  
Michael Ying Yang ◽  
Bodo Rosenhahn
Keyword(s):  
Cost Function ◽  
Mahalanobis Distance ◽  
Texture Features ◽  
Disease Diagnosis ◽  
Ct Images ◽  
Image Features ◽  
Active Shape Model ◽  
Liver Segmentation ◽  
Shape Model ◽  
Active Shape

Abstract Automatic 3D liver segmentation is a fundamental step in the liver disease diagnosis and surgery planning. This paper presents a novel fully automatic algorithm for 3D liver segmentation in clinical 3D computed tomography (CT) images. Based on image features, we propose a new Mahalanobis distance cost function using an active shape model (ASM). We call our method MD-ASM. Unlike the standard active shape model (ST-ASM), the proposed method introduces a new feature-constrained Mahalanobis distance cost function to measure the distance between the generated shape during the iterative step and the mean shape model. The proposed Mahalanobis distance function is learned from a public database of liver segmentation challenge (MICCAI-SLiver07). As a refinement step, we propose the use of a 3D graph-cut segmentation. Foreground and background labels are automatically selected using texture features of the learned Mahalanobis distance. Quantitatively, the proposed method is evaluated using two clinical 3D CT scan databases (MICCAI-SLiver07 and MIDAS). The evaluation of the MICCAI-SLiver07 database is obtained by the challenge organizers using five different metric scores. The experimental results demonstrate the availability of the proposed method by achieving an accurate liver segmentation compared to the state-of-the-art methods.

scholarly journals Nonintrusive Appliance Load Monitoring: An Overview, Laboratory Test Results and Research Directions

Sensors ◽  
2019 ◽  
Vol 19 (16) ◽  
pp. 3621 ◽  
Author(s):  
Augustyn Wójcik ◽  
Robert Łukaszewski ◽  
Ryszard Kowalik ◽  
Wiesław Winiecki
Keyword(s):  
Smart Home ◽  
State Of The Art ◽  
Measurement Data ◽  
Electricity Consumption ◽  
Identification Accuracy ◽  
Test Results ◽  
Research Directions ◽  
Laboratory Test Results ◽  
New Directions ◽  
Load Monitoring

Nonintrusive appliance load monitoring (NIALM) allows disaggregation of total electricity consumption into particular appliances in domestic or industrial environments. NIALM systems operation is based on processing of electrical signals acquired at one point of a monitored area. The main objective of this paper was to present the state-of-the-art in NIALM technologies for the smart home. This paper focuses on sensors and measurement methods. Different intelligent algorithms for processing signals have been presented. Identification accuracy for an actual set of appliances has been compared. This article depicts the architecture of a unique NIALM laboratory, presented in detail. Results of developed NIALM methods exploiting different measurement data are discussed and compared to known methods. New directions of NIALM research are proposed.

scholarly journals Multi Objective for PMU Placement in Compressed Distribution Network Considering Cost and Accuracy of State Estimation

2019 ◽  
Vol 9 (7) ◽  
pp. 1515 ◽  
Author(s):  
Kong ◽  
Wang ◽  
Yuan ◽  
Yu
Keyword(s):  
State Estimation ◽  
Estimation Error ◽  
Distribution Network ◽  
Measurement Data ◽  
Optimal Solution ◽  
Pareto Set ◽  
Measurement Unit ◽  
Nsga Ii ◽  
Multi Objective ◽  
Pmu Placement

A phasor measurement unit (PMU) can provide phasor measurements to the distribution network to improve observability. Based on pre-configuration and existing measurements, a network compression method is proposed to reduce PMU candidate locations. Taking the minimum number of PMUs and the lowest state estimation error as the objective functions and taking full observability of distribution network as the constraint, a multi objective model of optimal PMU placement (OPP) is proposed. A hybrid state estimator based on supervisory control and data acquisition (SCADA) and PMU measurements is proposed. To reduce the number of PMUs required for full observability, SCADA measurement data are also considered into the constraint by update and equivalent. In addition, a non-dominated sorting genetic algorithm-II (NSGA-II) is applied to solve the model to get the Pareto set. Finally, the optimal solution is selected from the Pareto set by the technique for order preference by similarity to ideal solution (TOPSIS). The effectiveness of the proposed method is verified by IEEE standard bus systems.

New Method to Assist Discrimination of Liver Diseases by Spherical SOM with Mahalanobis Distance

2012 ◽  
Vol 16 (1) ◽  
pp. 55-61 ◽  
Author(s):  
Norie Kanzaki ◽  
◽  
Akihiro Kanagawa ◽  
Keyword(s):  
Acute Hepatitis ◽  
Mahalanobis Distance ◽  
Blood Test ◽  
Input Data ◽  
Distance Measure ◽  
Medical Data ◽  
Data Conversion ◽  
Test Results ◽  
Automated Diagnosis ◽  
Test Items

Spherical SOM, an improved version of a kind of neutral network SOM, has successfully been applied to data analysis in a variety of fields achieving effective results. However, distance measure of commercial spherical SOM is limited to the Euclidean distance and it is not suitable enough to the analysis of biased data such as blood test results. The Mahalanobis distance is said to be effective for the analysis of such medical data. Therefore it is expected that better results should be obtained if spherical SOM with Mahalanobis distance is applied to the analysis of medical data. In this paper, we take blood test items as multi-dimensional vectors and convert the input data into Mahalanobis distance with the aim of developing an automated diagnosis system by spherical SOM with Mahalanobis distance as pseudo input data. Conversion of the input data into Mahalanobis distance ensures correct evaluations of the biased data of blood test results at the same time allowing automated diagnosis based on doctors’ intuitions and experiences. We have grouped subjects of diagnosis whose features were not well discriminated by conventional Mahalanobis distance and have administered detailed discrimination by the group and obtained better discrimination rates. While in the conventional studies TP rates for the following five categories, no liverrelated problem, hepatoma (liver cancer), acute hepatitis, chronic hepatitis and liver cirrhosis, were 100%, 70%, 100%, 80% and 60% respectively, they were 96%, 80%, 71%, 86% and 91% respectively with the proposed method. Significant results were obtained overall except for acute hepatitis.

scholarly journals Experimental Investigation of an Automotive Magnetorheological Shock Absorber

2017 ◽  
Vol 11 (4) ◽  
pp. 253-259
Author(s):  
Łukasz Jastrzębski ◽  
Bogdan Sapiński
Keyword(s):  
Shock Absorber ◽  
Measurement Data ◽  
Test Results ◽  
Experimental Examination ◽  
Piston Velocity ◽  
Testing Program ◽  
Technical Data ◽  
Piston Displacement ◽  
Operating Current ◽  
Set Up

AbstractThe study summarises the experimental examination of an automotive magnetorheological (MR) shock absorber under electrical and mechanical excitations, investigates its current and force responses and the energy dissipation in the system. The aim of experiments was to acquire measurement data that allows in next step of the research program to engineer an energy harvesting device for the absorber. The work covers basic technical data of the absorber, description of the experimental set-up, scenario of testing program and test results of the device. Of particular importance is the influence the operating current, piston displacement amplitude and piston velocity have on the absorber’s response.

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