• Journal of Electrical Engineering and Technology
• /
• v.3 no.2
• /
• pp.263-270
• /
• 2008

We studied partial discharge detection by sensing electromagnetic waves emitted from the partial discharge source in an HV Rotating Machine using a UWB sensor. In this study, we design a new type of compact low frequency UWB sensor based on micro-strip technology. We also perform many experiments of offline and dismantled testing compared with the existing HFCT on stator winding of the HV generator. We mention the detailed design of a new compact UWB sensor along with the time domain PRPD pattern and frequency domain results of partial discharge in the stator winding of a 6.6kV rotating machine by offline testing performed in a laboratory.

• International Journal of Advanced Culture Technology
• /
• v.8 no.4
• /
• pp.294-298
• /
• 2020

We was constructed of the spread movement with tremor layer point by the tractile-dot structure that was analyzed the squirm quake forms of the perception movement on the atom liquid. Algorithm of squirm quake forms was used to move the spread tremor on the atom state. To detect the tiny signal, we compared the association average value of the squirm quake form on the atom state. Their subject were issued the valuation standard and perception movement for basic atom condition by the spread tremor. We take to detect the tiny scores of average during perception movement side from the spread tremor that magnetic condition get to a variation of the Ma-αAVG and Ma-αMAX-MIN with 6.25±0.35 units, that electric condition get to a variation for the El-αAVG and El-αMAX-MIN with 5.68±0.42 units. The spread tremor was to investigate the capacity of the tremor form, to uptake a spread data of spread tremor level on the CCPL that was denoted the calm-classification form by the spread perception level system. As the squirm quake forms was demanded by the spread tremor signal, max-average values of perception movement were checked the spread position for association average data. We make mention of squirm quake forms for a signal association and a quake data signal of relation system.

• Annual Conference on Human and Language Technology
• /
• 2022.10a
• /
• pp.502-506
• /
• 2022

본 논문에서는 KorBERT와 개체 인기정보(popularity)를 이용한 개체연결 기술을 소개한다. 멘션인식(mention detection)은 KorBERT를 이용한 토큰분류 문제로 학습하여 모델을 구성하였고, 개체 모호성해소(entity disambiguation)는 멘션 컨텍스트와 개체후보 컨텍스트 간의 의미적 연관성에 대한 KorBERT기반 이진분류 문제로 학습하여 모델을 구성하였다. 개체 인기정보는 위키피디아의 hyperlink, inlink, length 정보를 활용하였다. 멘션인식은 ETRI 개체명 인식기를 이용한 모델과 비교하였을 경우, ETRI 평가데이터에서는 F1 0.0312, 국립국어원 평가데이터에서는 F1 0.1106의 성능 개선이 있었다. 개체 모호성해소는 KorBERT 모델과 Popularity 모델을 혼용한 모델(hybrid)에서 가장 우수한 성능을 보였다. ETRI 평가데이터에서는 Hybrid 모델에서의 개체 모호성 해소의 성능이 Acc. 0.8911 이고, 국립국어원 평가데이터에서는 Acc. 0.793 이였다. 최종적으로 멘션인식 모델과 개체 모호성해소 모델을 통합한 개체연결 성능은 ETRI 평가데이터에서는 F1 0.7617 이고, 국립국어원 평가데이터에서는 F1 0.6784 였다.

• Annual Conference on Human and Language Technology
• /
• 2021.10a
• /
• pp.264-269
• /
• 2021

상호참조해결은 주어진 문서에서 상호참조해결의 대상이 될 수 있는 멘션을 추출하고, 같은 개체를 의미하는 멘션 쌍 또는 집합을 찾는 자연어처리 작업이다. 하나의 멘션 내에 멘션이 될 수 있는 다른 단어를 포함하는 중첩 멘션은 순차적 레이블링으로 해결할 수 없는 문제가 있다. 본 논문에서는 이러한 문제를 해결하기 위해 멘션의 시작 단어의 위치를 여는 괄호('('), 마지막 위치를 닫는 괄호(')')로 태깅하고 이 괄호들을 예측하는 멘션 탐지 모델과 멘션 탐지 모델에서 예측된 멘션을 바탕으로 포인터 네트워크를 이용하여 같은 개체를 나타내는 멘션을 군집화하는 상호참조해결 모델을 제안한다. 실험 결과, 4개의 영어 대화 데이터셋에서 멘션 탐지 모델은 F1-score (Light) 94.17%, (AMI) 90.86%, (Persuasion) 92.93%, (Switchboard) 91.04%의 성능을 보이고, 상호참조해결 모델에서는 CoNLL F1 (Light) 69.1%, (AMI) 57.6%, (Persuasion) 71.0%, (Switchboard) 65.7%의 성능을 보인다.

• Journal of the Korean Institute of Gas
• /
• v.20 no.5
• /
• pp.104-111
• /
• 2016

Recently, the quantities of chemical material are increasing in chemical industries. At that time, release accident is increasing due to aging of equipment, mechanical failure, human error, etc. and industrial complexes found community properties in a specific area. For that matter, chemical release accident can lead to hight probability of large disaster. There is a need to analyze the boundaries optimal sensor placement calculated by selecting release scenarios through release condition and wether condition in a chemical process for release detection and response. This paper is to investigate chlorine release accident scenarios using COMSOL. Through accident scenarios, a numerical calculation is studied to determine optimized sensor placement with weight of detection probability, detection time and concentration. In addition, validity of sensor placement is improved by robustness analysis about unpredicted accident scenarios. Therefore, this verifies our studies can be effectively applicable on any process. As mention above, the result of this study can help to place mobile sensor, to track gas release based concentration data.

• Journal of Intelligence and Information Systems
• /
• v.19 no.3
• /
• pp.141-156
• /
• 2013

Social media is a representative form of the Web 2.0 that shapes the change of a user's information behavior by allowing users to produce their own contents without any expert skills. In particular, as a new communication medium, it has a profound impact on the social change by enabling users to communicate with the masses and acquaintances their opinions and thoughts. Social media data plays a significant role in an emerging Big Data arena. A variety of research areas such as social network analysis, opinion mining, and so on, therefore, have paid attention to discover meaningful information from vast amounts of data buried in social media. Social media has recently become main foci to the field of Information Retrieval and Text Mining because not only it produces massive unstructured textual data in real-time but also it serves as an influential channel for opinion leading. But most of the previous studies have adopted broad-brush and limited approaches. These approaches have made it difficult to find and analyze new information. To overcome these limitations, we developed a real-time Twitter trend mining system to capture the trend in real-time processing big stream datasets of Twitter. The system offers the functions of term co-occurrence retrieval, visualization of Twitter users by query, similarity calculation between two users, topic modeling to keep track of changes of topical trend, and mention-based user network analysis. In addition, we conducted a case study on the 2012 Korean presidential election. We collected 1,737,969 tweets which contain candidates' name and election on Twitter in Korea (http://www.twitter.com/) for one month in 2012 (October 1 to October 31). The case study shows that the system provides useful information and detects the trend of society effectively. The system also retrieves the list of terms co-occurred by given query terms. We compare the results of term co-occurrence retrieval by giving influential candidates' name, 'Geun Hae Park', 'Jae In Moon', and 'Chul Su Ahn' as query terms. General terms which are related to presidential election such as 'Presidential Election', 'Proclamation in Support', Public opinion poll' appear frequently. Also the results show specific terms that differentiate each candidate's feature such as 'Park Jung Hee' and 'Yuk Young Su' from the query 'Guen Hae Park', 'a single candidacy agreement' and 'Time of voting extension' from the query 'Jae In Moon' and 'a single candidacy agreement' and 'down contract' from the query 'Chul Su Ahn'. Our system not only extracts 10 topics along with related terms but also shows topics' dynamic changes over time by employing the multinomial Latent Dirichlet Allocation technique. Each topic can show one of two types of patterns-Rising tendency and Falling tendencydepending on the change of the probability distribution. To determine the relationship between topic trends in Twitter and social issues in the real world, we compare topic trends with related news articles. We are able to identify that Twitter can track the issue faster than the other media, newspapers. The user network in Twitter is different from those of other social media because of distinctive characteristics of making relationships in Twitter. Twitter users can make their relationships by exchanging mentions. We visualize and analyze mention based networks of 136,754 users. We put three candidates' name as query terms-Geun Hae Park', 'Jae In Moon', and 'Chul Su Ahn'. The results show that Twitter users mention all candidates' name regardless of their political tendencies. This case study discloses that Twitter could be an effective tool to detect and predict dynamic changes of social issues, and mention-based user networks could show different aspects of user behavior as a unique network that is uniquely found in Twitter.

• Journal of Haehwa Medicine
• /
• v.24 no.1
• /
• pp.25-36
• /
• 2015

Objective : This study aims to evaluate a risk of bias by Risk of Bias tool and RoBANS(Risk of Bias Assessment tool for Non-randomized Study) tool for clinical trial papers proving treatment effect of herbs to alopecia and provides the newest reason of effectiveness of herbs to alopecia. Methos : Data were collected through electronic database including NDSL, KISS, KMBASE, Koreantk, OASIS, KoreaMed, KISTI, Pubmd, Cochrane CENTRAL and CINAHL. Two experts in Oriental Medince assessed risk of bias of randomized controlled trials by Cochrane group's Risk of Bias tool and non-randomized controlled trials by RoBANS tool after searching, reviewing and selecting papers. Results : Total number of selected trials is 20 including 4 randomized controlled trials, 13 non-randomized controlled trials and 3 case reports. This study evaluates the risk of bias of 17 papers including 4 randomized controlled trials and 13 non-randomized controlled trials except 3 case reports by risk of bias tool and RoBANS tool. All papers of randomized controlled trials are evaluated unclear for random sequence generation and allocation concealment as there are no word on them. And all papers of non-randomized controlled trials are evaluated unclear for blinding of outcome assessments and relatively low for others. Conclusion : We must try to specify concretely methods of allocation concealment after planning and practicing it for reducing a selection bias in randomized controlled trials. Also report a reason of missing value and blinding outcome assessments. And we have to agonize and mention methods of blinding of researchers for reducing a detection bias in non-randomized controlled trials.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.12 no.7
• /
• pp.1173-1179
• /
• 2008

Since there are very strong clutter returns in airborne and ground weather radars used for the detection of low altitude weather hazards, the reliable weather data cannot be extracted from the weak Doppler weather signal without cancellation of these strong clutter returns. However, the clutter cancellation in Doppler frequency domain is not an easy task since even the fixed clutter returns not to mention the moving clutter can have Doppler shifts due to the antenna rotation and operational environment. Therefore, it was shown in this paper a simple array antenna system can be used for the efficient clutter cancellation in the spatial domain. The weather signal, various moving and fixed clutters were modelled and simulated to prove the performance of this adaptive array system. Also, the degree of accuracy in pulse-pair estimates of a weather radar was compared and analyzed from the simulated weather data.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.34 no.6
• /
• pp.299-308
• /
• 2020

This study aimed to evaluate the effects of Chuna therapy for Sciatica. We searched the following 16 online databases without a language restriction (Pubmed, Cochrane, Embase, CINAHL, Ovid, Kmbase, RISS, NDSL, OASIS, KISS, KNAL, KTKP, DBpia, CNKI, Wangfang, J-stage) to find randomized controlled clinical trials that used Chuna therapy for Sciatica. The methodological quality of randomized controlled clinical trials (RCTs) were assessed using the Cochrane risk of bias tool and meta-analysis were performed. Among 496 articles that were searched, 15 RCTs were finally selected for systematic review. 14 studies showed that Chuna therapy has positive effect on sciatica. Two studies noted that there were side effects, and the difference between the intervention group and the control group was statistically insignificant. One study noted no side effects and the rest of the study, there was no mention of side effects. Meta-analysis showed positive results for Chuna single therapy in terms of efficiency rate compared to painkiller, herb medicine excepting acupuncture. When comparing Chuna therapy plus acupuncture and acupuncture, Chuna therapy plus acupuncture had a more positive result than acupuncture in terms of efficiency rate. Cochrane Risk of Bias (RoB)evaluation method, most of the studies's selection, performance, detection and reporting bias were unclear. The studies showed that Chuna therapy can significantly effective on sciatica. However, most of the studies's Risk of Bias included in the analysis were not low enough. In the future, to prove the level of evidence of Chuna therapy, more high-quality studies will be needed.

• Food Science of Animal Resources
• /
• v.33 no.5
• /
• pp.640-645
• /
• 2013

The purpose of this study was to utilize the results as a basic data of benzoic acids in animal products that didn't mention in the quality standard of National Veterinary Research and Quarantine Service (NVRQS) to solve the conflict of international trade and administration. Set-Pak method listed in the quality standard of NVRQS, faster than auto distillation methods with same recovery selected as a pre treatment for the determination of benzoic acid. The regression curve of benzoic acid with Sep-Pak method was linear with the $R^2$ value of 0.999 and the limit of detection (LOD) and limit of quantitation (LOQ) was 0.058 mg/kg and 0.176 mg/kg, respectively. The benzoic acid in the fermented milk was detected after the fermentation stage by addition of starter culture with the level of 2.28~10.48 mg/kg and 0~16.5 mg/kg in the commercial fermented milk products without detection by the addition of syrup. In case of cheese products, the benzoic acids level was influenced by the curd formation (Camembert cheese) and the quality of natural cheese (processed cheese), by the way, the benzoic acid level of commercial natural cheese was 0~4.2 mg/kg, processed cheese was 0~20.8 mg/kg, respectively. Based on this result, it may be possible to utilize as a basic data for the systematic control the level of natural benzoic acids in raw material, processing and final products of animal origin.