• Title/Summary/Keyword: Time Series Cleaning

Search Result 15, Processing Time 0.021 seconds

Time Series Data Cleaning Method Based on Optimized ELM Prediction Constraints

  • Guohui Ding;Yueyi Zhu;Chenyang Li;Jinwei Wang;Ru Wei;Zhaoyu Liu
    • Journal of Information Processing Systems
    • /
    • v.19 no.2
    • /
    • pp.149-163
    • /
    • 2023
  • Affected by external factors, errors in time series data collected by sensors are common. Using the traditional method of constraining the speed change rate to clean the errors can get good performance. However, they are only limited to the data of stable changing speed because of fixed constraint rules. Actually, data with uneven changing speed is common in practice. To solve this problem, an online cleaning algorithm for time series data based on dynamic speed change rate constraints is proposed in this paper. Since time series data usually changes periodically, we use the extreme learning machine to learn the law of speed changes from past data and predict the speed ranges that change over time to detect the data. In order to realize online data repair, a dual-window mechanism is proposed to transform the global optimal into the local optimal, and the traditional minimum change principle and median theorem are applied in the selection of the repair strategy. Aiming at the problem that the repair method based on the minimum change principle cannot correct consecutive abnormal points, through quantitative analysis, it is believed that the repair strategy should be the boundary of the repair candidate set. The experimental results obtained on the dataset show that the method proposed in this paper can get a better repair effect.

Electrolyzed Water Cleaning for Semiconductor Manufacturing (전리수를 이용한 반도체 세정 공정)

  • 류근걸;김우혁;이윤배;이종권
    • Journal of the Semiconductor & Display Technology
    • /
    • v.2 no.3
    • /
    • pp.1-6
    • /
    • 2003
  • In the rapid changes of the semiconductor manufacturing technologies for early 21st century, it may be safely said that a kernel of terms is the size increase of Si wafer and the size decrease of semiconductor devices. As the size of Si wafers increases and semiconductor device is miniaturized, the units of cleaning processes increase. A present cleaning technology is based upon RCA cleaning which consumes vast chemicals and ultra pure water (UPW) and is the high temperature process. Therefore, this technology gives rise to environmental issue. To resolve this matter, candidates of advanced cleaning processes have been studied. One of them is to apply the electrolyzed water. In this work, electrolyzed water cleaning was compared with various chemical cleaning, using Si wafer surfaces by changing cleaning temperature and cleaning time, and especially, concentrating upon the contact angle. It was observed that contact angle on surface treated with Electrolyzed water cleaning was $4.4^{\circ}$ without RCA cleaning. Amine series additive of high pKa (negative logarithm of the acidity constant) was used to observe the property changes of cathode water.

  • PDF

Cleaning Noises from Time Series Data with Memory Effects

  • Cho, Jae-Han;Lee, Lee-Sub
    • Journal of the Korea Society of Computer and Information
    • /
    • v.25 no.4
    • /
    • pp.37-45
    • /
    • 2020
  • The development process of deep learning is an iterative task that requires a lot of manual work. Among the steps in the development process, pre-processing of learning data is a very costly task, and is a step that significantly affects the learning results. In the early days of AI's algorithm research, learning data in the form of public DB provided mainly by data scientists were used. The learning data collected in the real environment is mostly the operational data of the sensors and inevitably contains various noises. Accordingly, various data cleaning frameworks and methods for removing noises have been studied. In this paper, we proposed a method for detecting and removing noises from time-series data, such as sensor data, that can occur in the IoT environment. In this method, the linear regression method is used so that the system repeatedly finds noises and provides data that can replace them to clean the learning data. In order to verify the effectiveness of the proposed method, a simulation method was proposed, and a method of determining factors for obtaining optimal cleaning results was proposed.

In-Situ Dry-cleaning (ISD) Monitoring of Amorphous Carbon Layer (ACL) Coated Chamber

  • Lee, Ho-Jae;Park, George O.;Hong, Sang-Jeen
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2012.02a
    • /
    • pp.183-183
    • /
    • 2012
  • In the era of 45 nm or beyond technology, conventional etch mask using photoresist showed its limitation of etch mask pattern collapse as well as pattern erosion, thus hard mask in etching became necessary for precise control of etch pattern geometry. Currently available hard mask materials are amorphous carbon and polymetric materials spin-on containing carbon or silicon. Amorphous carbon layer (ACL) deposited by PECVD for etch hard mask has appeared in manufacturing, but spin-on carbon (SOC) was also suggested to alleviate concerns of particle, throughput, and cost of ownership (COO) [1]. SOC provides some benefits of reduced process steps, but it also faced with wiggling on a sidewall profile. Diamond like carbon (DLC) was also evaluated for substituting ACL, but etching selectivity of ACL was better than DLC although DLC has superior optical property [2]. Developing a novel material for pattern hard mask is very important in material research, but it is also worthwhile eliminating a potential issue to continuously develop currently existing technology. In this paper, we investigated in-situ dry-cleaning (ISD) monitoring of ACL coated process chamber. End time detection of chamber cleaning not only provides a confidence that the process chamber is being cleaned, but also contributes to minimize wait time waste (WOW). Employing Challenger 300ST, a 300mm ACL PECVD manufactured by TES, a series of experimental chamber cleaning runs was performed after several deposition processes in the deposited film thickness of $2000{\AA}$ and $5000{\AA}$. Ar Actinometry and principle component analysis (PCA) were applied to derive integrated and intuitive trace signal, and the result showed that previously operated cleaning run time can be reduced by more than 20% by employing real-time monitoring in ISD process.

  • PDF

A Study on the Household Work Time's Change and Its Structure in Urban Home Makers (도시 가정주부의 가사노동시간변화와 구조에 관한 연구)

  • 김선희
    • Journal of the Korean Home Economics Association
    • /
    • v.27 no.1
    • /
    • pp.111-126
    • /
    • 1989
  • The aim of the present study is to research into the household work time change and its structure in urban home makers by the choosen eleven studies and KBS's Data 1981, 1983, 1985, 1987. This study were proceeded under some limitations, it is choosen eleven studies that is different region: large city, medium and small town, and the household work's categories of original auther were changed. And KBS's Data was composed of general formation without personal character of home maker: FLC, number of childeren, family type, education, region. Although this study have a certain meaning of implementation, research into the household work time change and its's structure. The major findings of this study can be autlined as follows: (1) Total household work time did'nt so much changed through the choosen eleven studies compared with the last twenty years ago. In the change of each province household work time, time connected with meals and dwelling did not showed consistancy of change. But cloth laundering and mending time of 80's were declined compared with 70's. Family care time of 80's was increased, home management and buying time was declined untill '85, but again increasing trend '87. In choosen eleven studies, the household work time structure of urban home makers can be outlined: time connected with Meals>Family care>Cloth laundering and mending>Dwelling>Home management and Buying. (2) KBS's time-series data were analized as follows: a) Total household work time of '87 was declining gradually in weekday (34 minutes), sat. (41 minutes), sun (1 house and 2 minutes) compared with '81. b) The change of each province household work time: the time of cooking and sewing home management were declining gradually in its Mean time and its ratio of acters. The acter ratio of household worker in '81, '83, '85 was composed Cooking > Cleaning > Laundering > Home management > Buying > Child care > Sewing. In '87 was composed Cooking > Cleaning > Laundering > Buying > Home management > Child care > Sewing. c) The structure of household work time revealed some differences in each year and a day of the week.

  • PDF

Column cleaning, regeneration and storage of silica-based columns (실리카 기반 컬럼의 세척, 재생 및 보관 가이드)

  • Matt James;Mark Fever
    • FOCUS: LIFE SCIENCE
    • /
    • no.1
    • /
    • pp.1.1-1.4
    • /
    • 2024
  • This article provides comprehensive guidance on the maintenance, cleaning, regeneration, and storage of silica-based HPLC (High-Performance Liquid Chromatography) columns. The general considerations emphasize the importance of using in-line filters and guard cartridges to protect columns from blockage and irreversible sample adsorption. While these measures help, contamination by strongly adsorbed sample components can still occur over time, leading to an increase in back pressure, loss of efficiency, and other issues. To maximize column lifetime, especially with UHPLC (Ultra-High Performance Liquid Chromatography) columns, it is advisable to use ultra-pure solvents, freshly prepared aqueous mobile phases, and to filter all samples, standards, and mobile phases. Additionally, an in-line filter system and sample clean-up on dirty samples are recommended. However, in cases of irreversible compound adsorption or column voiding, regeneration may not be possible. The document also provides specific recommendations for column cleaning procedures, including the flushing procedures for various types of columns such as reversed phase, unbonded silica, bonded normal phase, anion exchange, cation exchange, and size exclusion columns for proteins. The flushing procedures involve using specific solvents in a series to clean and regenerate the columns. It is emphasized that the flow rate during flushing should not exceed the specified limit for the particular column, and the last solvent used should be compatible with the mobile phase. Furthermore, the article outlines the storage conditions for silica based HPLC columns, highlighting the impact of storage conditions on the column's lifetime. It is recommended to flush all buffers, salts, and ion-pairing reagents from the column before storage. The storage solvent should ideally match the one used in the initial column test chromatogram provided by the manufacturer, and column end plugs should be fitted to prevent solvent evaporation and drying out of the packing bed.

  • PDF

Natural Dyeing of Silk Fabrics with Dansam (Salvia miltiorrhiza Bunge) Extract (단삼 추출액을 이용한 견직물의 천연염색)

  • Nam, Jeongran;Lee, Jeongsook
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.37 no.7
    • /
    • pp.874-881
    • /
    • 2013
  • Dansam (Salvia miltiorrhiza Bunge) is a perennial plant that belongs to the Labiatae family and is characterized by red pigment found in the epidermis of its roots. Research on the dyeability of Dansam extract was performed with repeated trials under various conditions such as temperature, time, and mordant treatment. Silk fabrics were dyed with Dansam extract and mordanted with various agents such as Al, Fe, Cu, and Sn to evaluate the dyeability and functionality of Dansam extract; subsequently, the K/S value and the change of surface color were analyzed using a colorimeter. In addition, the dyeability of dyed fabrics (such as color fastness to washing, dry cleaning fastness, rubbing fastness and light fastness) and functionality (such as antibacterial activity and deodorization) were analyzed. The surface colors of all dyed fabrics were recorded and the results showed the presence of mostly YR series of colors; in addition, a GY color series appeared in the Fe pre-mordants of the silk fabric. The highest K/S values were recorded in Fe post-mordants. The washing fastness were Level 3 and Level 4; in addition, the dry-cleaning fastness showed excellent results at Level 4 and Level 5. The rubbing fastness was satisfactory at Level 3 and Level 4 and the light fastness was satisfactory at Level 4. The results of the measurements (that pertained to the antibacterial activity of fabrics dyed with Dansam extract) showed a 99.9% bacteria reduction rate of Staphylococcus aureus and Klebsiella pneumoniae. In regards to deodorization ability, dyed fabrics were found to have higher deodorization rates than those not dyed. The dyed fabric demonstrated exceptional deodorization qualities.

A Study of Housing Environment Problems through the Daily newspapers ( II ) -Centering around a excretion and fixing process of lavatory- (일간지를 통해 본 주거환경문제의 연구 ( II ) - 분뇨에서 변소의 정착과정을 중심으로 -)

  • 신경주
    • Journal of the Korean housing association
    • /
    • v.3 no.2
    • /
    • pp.89-99
    • /
    • 1992
  • We discussed the change of housing environmental problems from the early 1900s to the present in Study(I). This study(II) which secendly research of study(I) analyzed the fixing precess of a lavatory centering around a excretion which was a serious housing environmental problem in 1920 to 1940. The documentary research method was used for this study. Articles of content analysis(N=185) were published in 1920 to 1990 which were The Deng-A daily news article about a excretion and a lavatory. The main content of this study was examined the change, such as the number of whole article, the column number of article by time series. and the content of article by subject. 1. The number of whole article by time series was collected mainly in1920s-1930s. In 1940s-1960s, one-two column of article was appeared generally and three-four, five column of article was appeared in 1970-1980. 2. Contents of article was divided into two classes, excretion and lavatory. Contents of excretion was 1) a use of fertilizer 2) the method of transportation 3) a cost of gathering 4) a place of disposal 5) the problem of cleaning. Contents of lavatory was 1) a public lavatory 2) a flush toilet 3) a sanitary conditions 3. 1) A use of fertilizer was concentrated in 1920s-1930s, and problems of it was solved more or less by change of management method. Transportation of excretion developed such as \ulcornerGue\ulcorner->a coach of tank style->underground transportation->a dung car of absorption style. Disposal place of excretion was a cause of dissatisfaction in 1920s and it is serious problem Today. A duty of excretion gathering was transfered to a private worker in 1978. The accunulation problem of excretion was continued until 1940s-1950s. The management law of waste matters was proclaimed in 1986. 2) A public lavatory was planned in 1924 for the first time, and it is insufficient in these days, A settlement of public lavatory in building which has upward of 20pyung became obligation in 1973. The problem of water contamination which by poor septic tank was happened in 1970s-1980s.

  • PDF

Quality Control of Observed Temperature Time Series from the Korea Ocean Research Stations: Preliminary Application of Ocean Observation Initiative's Approach and Its Limitation (해양과학기지 시계열 관측 자료 품질관리 시스템 구축: 국제 관측자료 품질관리 방안 수온 관측 자료 시범적용과 문제점)

  • Min, Yongchim;Jeong, Jin-Yong;Jang, Chan Joo;Lee, Jaeik;Jeong, Jongmin;Min, In-Ki;Shim, Jae-Seol;Kim, Yong Sun
    • Ocean and Polar Research
    • /
    • v.42 no.3
    • /
    • pp.195-210
    • /
    • 2020
  • The observed time series from the Korea Ocean Research Stations (KORS) in the Yellow and East China Seas (YECS) have various sources of noise, including bio-fouling on the underwater sensors, intermittent depletion of power, cable leakage, and interference between the sensors' signals. Besides these technical issues, intricate waves associated with background tidal currents tend to result in substantial oscillations in oceanic time series. Such technical and environmental issues require a regionally optimized automatic quality control (QC) procedure. Before the achievement of this ultimate goal, we examined the approach of the Ocean Observatories Initiative (OOI)'s standard QC to investigate whether this procedure is pertinent to the KORS. The OOI QC consists of three categorized tests of global/local range of data, temporal variation including spike and gradient, and sensor-related issues associated with its stuck and drift. These OOI QC algorithms have been applied to the water temperature time series from the Ieodo station, one of the KORS. Obvious outliers are flagged successfully by the global/local range checks and the spike check. Both stuck and drift checks barely detected sensor-related errors, owing to frequent sensor cleaning and maintenance. The gradient check, however, fails to flag the remained outliers that tend to stick together closely, as well as often tend to mark probably good data as wrong data, especially data characterized by considerable fluctuations near the thermocline. These results suggest that the gradient check might not be relevant to observations involving considerable natural fluctuations as well as technical issues. Our study highlights the necessity of a new algorithm such as a standard deviation-based outlier check using multiple moving windows to replace the gradient check and an additional algorithm of an inter-consistency check with a related variable to build a standard QC procedure for the KORS.

Dyeing Properties and Functionality of Hot-water Extract from Juniperus chinensis Heartwood (향나무 심재 열수추출물의 염색성과 기능성)

  • Nam, Ki Yeon;Lee, Jung Soon
    • Textile Coloration and Finishing
    • /
    • v.25 no.3
    • /
    • pp.181-193
    • /
    • 2013
  • The purpose of this study is to investigate dyeing properties and functionality of cotton and silk fabrics dyed with hot-water extract from Juniperus chinensis heartwood. Water-soluble dye of Juniperus chinensis heartwood extracted with distilled water was expressed YR color series. Dye uptake of cotton continued to increase according to the increase of the dye concentration. Its variation trends were shown to be similar to the isothermal absorption curve of the Freundlich. Dye uptake of silk was better than cotton, increased depending on increasing concentration of the dye, dyeing time and temperature. Its variation trends were shown to be similar to the isothermal absorption curve of the Langmuir. As the pH increased, the dye uptake of fabrics reduced and showed increased on red tinge. Colors of the dyed fabrics were various, depending on dye concentration and the mordant type and mordant concentration. Washing fastness, light fastness and perspiration fastness were not good. However, rubbing and dry cleaning fastness showed relatively good grade. Dyed fabrics of ultraviolet-cut ability and deodorant ability were improved. And dyed fabrics showed antimicrobial abilities of 99.9% against Staphylococcus aureus.