• 상하수도학회지
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• 제24권5호
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• pp.573-580
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• 2010

Average pressure in a pipe network is one of critical factors to estimate the flow distribution and to calculate UARL (Unavoidable Annual Real Losses) value in ILI (Infrastructure Leakage Index). While its collection period and measuring location are essential to obtain average pressure, their standard method have not been established so far. In this study, proper method including its procedure for data collection period and measuring point for average pressure were suggested using non-exceedance probability concept in the water distribution network.

• Korean Journal of Radiology
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• 제19권6호
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• pp.1172-1178
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• 2018

Objective: To analyze and compare the age of data in contemporary research articles published in representative general radiology journals. Materials and Methods: We searched for articles reporting original research studies analyzing patient data that were published in the print issues of the Korean Journal of Radiology (KJR), European Radiology (ER), and Radiology in 2017. Eligible articles were reviewed to extract data collection period (time from first patient recruitment to last patient follow-up) and age of data (time between data collection end and publication). The journals were compared in terms of the proportion of articles reporting the data collection period to the level of calendar month and regarding the age of data. Results: There were 50, 492, and 254 eligible articles in KJR, ER, and Radiology, respectively. Of these, 44 (88%; 95% confidence interval [CI]: 75.8-94.8%), 359 (73%; 95% CI: 68.9-76.7%), and 211 (83.1%; 95% CI: 78-87.2%) articles, respectively, provided enough details of data collection period, revealing a significant difference between ER and Radiology (p = 0.002). The age of data was significantly greater in KJR (median age: 826 days; range: 299-2843 days) than in ER (median age: 570 days; range: 56-4742 days; p < 0.001) and Radiology (median age: 618; range: 75-4271 days; p < 0.001). Conclusion: Korean Journal of Radiology did not fall behind ER or Radiology in reporting of data collection period, but showed a significantly greater age of data than ER and Radiology, suggesting that KJR should take measures to improve the timeliness of its data.

• 한국콘텐츠학회논문지
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• 제10권8호
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• pp.51-58
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• 2010

이동 싱크를 이용한 데이터 수집에서 센서 노드들이 이동 싱크의 통신반경에 포함되는 시간은 불균등하다. 불균등한 시간내에 효율적인 데이터 수집을 위해서는 이동 싱크와 센서 노드간 데이터 수집 스케줄링이 필요하다. 기존 이동 싱크에 이용된 스케줄링 기법들은 데이터 수집을 위해 이동 싱크의 통신범위에 머무는 시간과 이동 싱크로 수집된 데이터양 등을 고려하였다. 하지만 기존 연구들은 센서 네트워크에서 수집되는 데이터의 특성을 고려하지 않았다. 본 논문에서는 센서 노드별 데이터 수집 주기와 이동 싱크와 센서 노드사이의 데이터 수집 주기로 구성된 TDMA 스케줄링 기법을 제안하였다. 또한 온도, 습도 등과 같이 일정하게 증가 혹은 감소하는 센서 데이터의 특성을 고려한 TDMA 스케줄링 기반의 데이터 수집기법을 제안하였다. 제안한 데이터 수집 기법은 센서 노드별 전체 데이터의 수집이 아닌 사용자가 설정한 임계 값보다 크게 변한 데이터를 수집한다. 제안하는 기법의 우수성을 보이기 위해 기존 스케줄링 기법 중 데이터 균등 수집을 목표로 하는 DWEDF 기법과 성능 평가를 수행하였다. 실험 결과 제안하는 기법이 기존 DWEDF 기법에 비해 데이터 수집에 소모되는 에너지가 약23% 줄었고, 센서 노드의 데이터 수집실패가 감소하였다.

• Journal of Multimedia Information System
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• 제7권2호
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• pp.137-140
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• 2020

In this paper, we propose a simplified tag collection algorithm to improve the performance of ISO / IEC 18000-7, the standard of active RFID systems. In the proposed algorithm, the collection command is modified to include the result of the listening period response from the previous round. The tag, which has received the collection command, checks whether the slot to which it has responded is collided, transmits additional data to its data slot without a point-to-point read command and sleep command, and transitions to the sleep mode. The collection round in the standard consists of a series of collection commands, collection responses, read commands, read responses, and sleep commands. On the other hand, in the proposed tag collection algorithm, one collection round consists only of a collection command and a collection response. As a result of performance analysis, it can be seen that the proposed technique shows superior performance compared to the standard.

• 한국신뢰성학회지:신뢰성응용연구
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• 제8권1호
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• pp.1-13
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• 2008

A methodology for collection and analysis of automotive field reliability data is presented. Automotive warranty system usually covers a pre-determined period of time and/or mileage accumulation. Therefore mileage information for the vehicles that have not experienced any failure or problems during the warranty period is not available. In this paper, a reliability analysis method using the estimated mileage distribution from an additional survey for vehicles that have not any record during the warranty period is proposed. Methods of reliability analysis using the warranty information collected under the EU and US warranty policies are also provided.

• 한국의상디자인학회지
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• 제25권2호
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• pp.111-122
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• 2023

This study aims to collect Big Data related to DIY clothing, analyze the results on a year-by-year basis, understand consumers' perceptions, the status, and reality of DIY clothing. The reference period for the evaluation of DIY clothing trends was set from 2012 to 2022. The data in this study was collected and analyzed using Textom, a Big Data solution program certified as a Good Software by the Telecommunications Technology Association (TTA). For the analysis of fabric-related DIY products, the keyword was set to "DIY clothing", and for data cleansing following collection, the "Espresso K" module was employed. Also, via data collection on a year-by-year basis, a total of 11 lists were generated and the collected data was analyzed by period. The following are the findings of this study's data collection on DIY clothing. The total number of keywords collected over a period of ten years on search engines "Naver" and "Google" between January 1, 2012 and December 31, 2022 was 16,315, and data trends by period indicate a continuous upward trend. In addition, a keyword analysis was conducted to analyze TF-IDF (Term Frequency-Inverse Document Frequency), a statistical measure that reflects the importance of a word within data, and the relationship with N-gram, an analysis of the correlation concerning the relationship between words. Using these results, it was possible to evaluate the popularity and growing tendency of DIY clothing products in conjunction with the evolving social environment, as well as the desire to explore DIY trends among consumers. Therefore, this study is valuable in that it provides preliminary data for DIY clothing research by analyzing the status and reality of DIY products, and furthermore, contributes to the development and production of DIY clothing.

• 상하수도학회지
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• 제18권1호
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• pp.66-72
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• 2004

In this study, quantity and quality of collected rainwater by sand, gravel, soil, lawn and concrete surface, as collection materials were investigated and Rainwater Collection Prediction Model was developed to predict the amount of collected rainwater. The quantity of collected rainwater in concrete surface, gravel, sand, soil and lawn collection system was 1,067L(93.2%), 1,006L(87.8%), 902L(78.8%), 800L(69.9%), 788.5L(68.8%) for 8 months period, respectively. The average turbidity of collected rainwater in concrete surface, gravel, sand, soil and lawn collection system was 3.2NTU, 2.2NTU, 1.9NTU, 1.7NTU, 1.5NTU for 8 months period, respectively. For sand collection material, predicted amount by the Model and actual collected amount were 931.5L and 902L, which were very closed. For gravel collection material, predicted amount by Model and actual collected amount were 1,028.21. and 1,006L, which were very closed. To simulate the optimal rainwater storage volume, the rainfall and evaporation data in Dae-jeon city were used. For sand collection system with 30m2 area, the maximum storage volume was $17m^3$ and 62% of the year was secured for use of 240L/day.

• 대한토목학회논문집
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• 제32권3D호
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• pp.205-212
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• 2012

일반국도 교통량조사는 크게 수시조사와 상시조사로 나누어진다. 수시조사는 상시조사와 달리 표본조사로 시행되고 있으며 조사 시기에 따라 AADT에 대한 오차의 크기가 달라진다. 따라서 본 연구에서는 수시조사의 AADT 추정의 정확도를 높이기 위하여 도로 유형별로 AADT와의 오차가 작은 수시조사 시기를 파악하고자 하였다. 그리고 상시조사는 조사 지점에 설치되어 있는 장비의 고장이나 오작동 등으로 인하여 교통량 자료가 정상적으로 수집되지 않아 해당 지점의 교통량 변동을 제대로 파악할 수 없는 경우가 자주 발생한다. 따라서 본 연구에서는 장비 설치년도, 중차량 비율 등이 장비의 고장이나 오작동의 원인이 될 수 있는 지를 장비 유지보수 횟수와의 상관관계 분석을 통하여 파악하고자 하였다.

• 보존과학연구
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• 통권22호
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• pp.155-171
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• 2001

The facilities of exhibition and collection for cultural properties is affected by environmental pollution. In order to accumulate a store of basic data, we was investigated eight points(three points at exhibition room and five points at collection room) at four institutes, from December 2000 to March 2001.As a result of investigation, the temperature of A-Exhibition room measured low because of don’t moved HVAC(Heating, Ventilation and Air-Conditioning) System, B Exhibition room is dry for the effect of air-conditioner and the air pollutants concentration of C-Exhibition room is high for the kind of an exhibition room. The air-condition was varied within the open period. The air pollutants concentration of A-Collection room is measured high because the air-pollutants is generated in a new buildings and the air pollutants concentration of C-1 & C-2-Collection room is high for the kind of an collection room. It is necessary to ventilate sufficiently.

• 유통과학연구
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• 제19권10호
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• pp.43-54
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• 2021

Purpose: The restrictions posed by the COVID-19 pandemic have affected the normal functioning of the economy. A country like India is facing a lot of concerns in all its sectors especially, in its fiscal system. This paper makes an attempt to examine the impact of COVID-19 first wave on Goods and Service Tax revenue collection and distribution in India and also studies the impact of COVID-19 first wave on the state wise GST revenue of the country. Research Design, Data and Methodology: Our study is based on published GST revenue data. Tools such as Paired Sample t-test, Wilcoxon signed rank test are employed to analyze the data. Results: Our results provide evidence that there is a sharp decline in the GST revenue in the months after the lockdown announcement. The large states show no significance impact of COVID-19 pandemic on GST collection. Whereas, small states like Manipur and Goa show significant difference in GST revenue collection & distribution between the pre and post lockdown period. Conclusion: The outcome of this study will help the policymakers to analyze the extent of the GST revenue loss to the government treasury and will allow them to take appropriate measures in the future.