• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.23 no.2
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• pp.119-131
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• 2024

Understanding accurate traffic performance is crucial for ensuring efficient highway operation and providing a sustainable mobility environment. On the other hand, an immediate and precise estimation of highway traffic performance faces challenges because of infrastructure and technological constraints, data processing complexities, and limitations in using integrated big data. This paper introduces a framework for estimating traffic performance by analyzing real-time data sourced from toll collection systems and dedicated short-range communications used on highways. In particular, this study addresses the data errors arising from segmented information in data, influencing the individual travel trajectories of vehicles and establishing a more reliable Origin-Destination (OD) framework. The study revealed the necessity of trip linkage for accurate estimations when consecutive segments of individual vehicle travel within the OD occur within a 20-minute window. By linking these trip ODs, the daily average highway traffic performance for South Korea was estimated to be248,624 thousand vehicle kilometers per day. This value shows an increase of approximately 458 thousand vehicle kilometers per day compared to the 248,166 thousand vehicle kilometers per day reported in the highway operations manual. This outcome highlights the potential for supplementing previously omitted traffic performance data through the methodology proposed in this study.

• KEPCO Journal on Electric Power and Energy
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• v.2 no.4
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• pp.557-562
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• 2016

계량데이터 관리 시스템은 수용가에서 검침된 계량데이터를 수집하고 관리하는 시스템이다. 이 시스템에는 검침된 데이터의 오검침과 유효성을 판단하는 검증과 누락된 검침값이나 오검침으로 판단된 구간값을 추정하는 VEE 알고리즘이 있다. 그러나 기존의 VEE 알고리즘은 현장 데이터의 특성을 반영하지 않고 검증하고 추정하기 때문에 그만큼 신뢰성과 정확도가 낮아지는 단점이 있다. 본 논문에서는 검증 신뢰성과 추정 정확도를 향상시킬 수 있는 차세대 VEE 알고리즘을 제안한다.

• Proceedings of the Korean Association for Survey Research Conference
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• 2001.04a
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• pp.27-59
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• 2001

The population enumeration data from the decennial U.S. census are used in the apportionment of the U.S. House of Representatives and federal revenue sharing. The primary purpose of this study is to examine the various issues about the U.S. Census 2000. More specifically, this paper analyzes the sociopolitical implications of the racial and ethnic variations in net undercount rate in the census. In addition, we investigate the politics of race and ethnicity centering the census questions on race and use of sampling for adjustment of the enumeration data.

• Survey Research
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• v.2 no.2
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• pp.27-59
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• 2001

The population enumeration data from the decennial U.S. census are used in the apportionment of the U.S. House of Representatives and federal revenue sharing. The primary purpose of this study is to examine the various issues about the U.S. Census 2000. More specifically, this paper analyzes the sociopolitical implications of the racial and ethnic variations in net undercount rate in the census. In addition. we investigate the politics of race and ethnicity centering the census questions on race and use of sampling for adjustment of the enumeration data.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.83-85
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• 2003

This paper presents a correction technique of missing load data. In this paper, the ARIMA(Autoregressive Integrated Moving Average) model and Piecewise Cubic Interpolation are applied to seek the missing parameters. The new model has been tested under a variety of conditions and it is shown in this paper to produce excellent results. It is helpful for operators to designed the load duration curve.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2022.06a
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• pp.93-96
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• 2022

IoT 기기의 보급 및 확산으로 많은 산업군에서 이를 바탕으로 시계열 데이터를 획득하고 분석하려는 시도가 확대되고 있다. 시간의 흐름에 따라 저장된 데이터들은 주기에 따라 특정 패턴을 갖는 경우가 많으며 이러한 패턴을 파악한다면 주요 산업군의 의사 결정에 도움이 된다. 그러나 IoT 기기의 수집 오류 및 네트워크 환경에 의해 대부분의 시계열 데이터들은 누락 데이터, 이상 데이터를 갖고 있으며 이를 처리하지 않고 분석할 경우 오히려 잘못된 결과를 초래한다. 본 논문에서는 패턴 파악을 위해 '시간, 일, 주, 월, 년' 등 시간의 주기를 기준으로 데이터를 분할하며 이에 기반하여 데이터셋을 재구성하고 활용 가능한 데이터와 불가능한 데이터로 구분한다. 선별된 데이터셋은 클러스터링에 적용하였으며, 제안하는 방법을 적용할 경우 주기를 갖는 시계열 데이터를 활용하는 분석 및 학습에서 더 나은 결과를 보임을 확인하였다.

• Spatial Information Research
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• v.17 no.1
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• pp.67-77
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• 2009

Mobile mapping systems with CCD cameras, GPS and IMU etc. can acquire massive photos and geographic informations along by roads. But it is easy to involve many errors or omissions of images and informations about roads and facilities with various files. And there were contained any conflicts or non-consistencies in massive mobile mapping data which were acquired by multiple survey teams in various survey regions. As an image tag standard, Exif helps us to encapsulate the precise GPS times and essential informations in the header of JPEG files and uses with the identification code for consistent managements of massive mobile mapping data in this paper. And Systematic management systems with data synchronization technology manage more consistently massive photos and their information.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.5
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• pp.916-922
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• 2001

A medium access control protocol is proposed for integrated voice and data services in the packet CDMA network with a small coverage. Uplink channels are composed of time slots and multiple spreading codes for each slot. This protocol gives higher access priority to the delay-sensitive voice traffic than to the data traffic. During a talkspurt, voice terminals reserve a spreading code to transmit multiple voice packets. On the other hand, whenever generating a data packet, data terminals transmit a packet based on the status Information of spreading codes in the current slot, which is received from base station. In this protocol, voice packet does not come into collision with data packet. Therefore, this protocol can increase the maximum number of voice terminals.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.9 no.4
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• pp.25-31
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• 2009

In this paper, the implementation of a production control system based on RFID has been studied in order to obtain an exact Cost Center data such as the name of workers included a process of work and a time period to finish the process. The cost center of a worker will be correctly obtained by checking the work time using RFID tag data and by transmitting the data to a server of ERP or POP system. And also warming up time, cleaning time, power failure, and out of order sign will be checked and calculated using the data stored in RFID tags attached in workers and machine facilities. Therefore, exact Cost Center data will be obtained by the production control system with touch screens entering the data according to the situation in real time.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.05a
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• pp.513-515
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• 2022

Manufacturing data collected using IoT devices in a smart factory environment is generally reliable except for noises caused by external factors. However, unlike manufacturing data that is collected mechanically, process data manually recorded by field-workers can cause problems such as the misspelled entries or the missing entries. Therefore, process data must be validated before being used as training data for artificial intelligence models. In this paper, based on the fact that which is a linear relationship between the power consumption of the MCT machine and the production of the product recorded by the field-workers, we detect anomalous records of the workers using robust linear regression.