• Title/Summary/Keyword: Science & Technology Databases

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Analysis of Posting Preferences and Prediction of Update Probability on Blogs (블로그에서 포스팅 성향 분석과 갱신 가능성 예측)

  • Lee, Bum-Suk;Hwang, Byung-Yeon
    • Journal of KIISE:Databases
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    • v.37 no.5
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    • pp.258-266
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    • 2010
  • In this paper, we introduce a novel method to predict next update of blogs. The number of RSS feeds registered on meta-blogs is on the order of several million. Checking for updates is very time consuming and imposes a heavy burden on network resources. Since blog search engine has limited resources, there is a fix number of blogs that it can visit on a day. Nevertheless we need to maximize chances of getting new data, and the proposed method which predicts update probability on blogs could bring better chances for it. Also this work is important to avoid distributed denial-of-service attack for the owners of blogs. Furthermore, for the internet as whole this work is important, too, because our approach could minimize traffic. In this study, we assumed that there is a specific pattern to when a blogger is actively posting, in terms of days of the week and, more specifically, hours of the day. We analyzed 15,119 blogs to determine a blogger's posting preference. This paper proposes a method to predict the update probability based on a blogger's posting history and preferred days of the week. We applied proposed method to 12,115 blogs to check the precision of our predictions. The evaluation shows that the model has a precision of 0.5 for over 93.06% of the blogs examined.

An Efficient Location Encoding Method Based on Hierarchical Administrative District (계층적 행정 구역에 기반한 효율적인 위치 정보 표현 방식)

  • Lee Sang-Yoon;Park Sang-Hyun;Kim Woo-Cheol;Lee Dong-Won
    • Journal of KIISE:Databases
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    • v.33 no.3
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    • pp.299-309
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    • 2006
  • Due to the rapid development in mobile communication technologies, the usage of mobile devices such as cell phone or PDA becomes increasingly popular. As different devices require different applications, various new services are being developed to satisfy the needs. One of the popular services under heavy demand is the Location-based Service (LBS) that exploits the spatial information of moving objects per temporal changes. In order to support LBS efficiently, it is necessary to be able to index and query well a large amount of spatio-temporal information of moving objects. Therefore, in this paper, we investigate how such location information of moving objects can be efficiently stored and indexed. In particular, we propose a novel location encoding method based on hierarchical administrative district information. Our proposal is different from conventional approaches where moving objects are often expressed as geometric points in two dimensional space, (x,y). Instead, in ours, moving objects are encoded as one dimensional points by both administrative district as well as road information. Our method is especially useful for monitoring traffic situation or tracing location of moving objects through approximate spatial queries.

Extended Buffer Management with Flash Memory SSDs (플래시메모리 SSD를 이용한 확장형 버퍼 관리)

  • Sim, Do-Yoon;Park, Jang-Woo;Kim, Sung-Tan;Lee, Sang-Won;Moon, Bong-Ki
    • Journal of KIISE:Databases
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    • v.37 no.6
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    • pp.308-314
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    • 2010
  • As the price of flash memory continues to drop and the technology of flash SSD controller innovates, high performance flash SSDs with affordable prices flourish in the storage market. Nevertheless, it is hard to expect that flash SSDs will replace harddisks completely as database storage. Instead, the approach to use flash SSD as a cache for harddisks would be more practical, and, in fact, several hybrid storage architectures for flash memory and harddisk have been suggested in the literature. In this paper, we propose a new approach to use flash SSD as an extended buffer for main buffer in database systems, which stores the pages replaced out from main buffer and returns the pages which are re-referenced in the upper buffer layer, improving the system performance drastically. In contrast to the existing approaches to use flash SSD as a cache in the lower storage layer, our approach, which uses flash SSD as an extended buffer in the upper host, can provide fast random read speed for the warm pages which are being replaced out from the limited main buffer. In fact, for all the pages which are missing from the main buffer in a real TPC-C trace, the hit ratio in the extended buffer could be more than 60%, and this supports our conjecture that our simple extended buffer approach could be very effective as a cache. In terms of performance/price, our extended buffer architecture outperforms two other alternative approaches with the same cost, 1) large main buffer and 2) more harddisks.

The Effect of Virtual Reality Programs on Upper Extremity Function in Stroke Patients : A Meta-Analysis (뇌졸중 환자의 가상현실 프로그램이 상지기능에 미치는 영향 : 메타분석)

  • Cho, Sung-Hyoun;Choi, Ki-Bok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.8
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    • pp.429-439
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    • 2020
  • This study examined the effect size of virtual reality programs on the upper extremity function of stroke patients through a meta-analysis. Databases, such as the Research Information Sharing Service, the Korean Studies Information Service System, the National Library of Korea, the Korean Citation Index, and the National Digital Science Library, were used. Previous articles were surveyed for virtual reality programs between January 2010 and June 2019. A meta-analysis was performed by selecting the final 14 studies based on the PICO standard. The RoB and RoBANS tools were used as quality assessment tools for randomized and non-randomized control trials, respectively. The CMA 3.0 program was used to calculate the effect size of each study. Sub-group analysis, meta-regression analysis, and publication bias were performed. The total effect size of the virtual reality programs on the upper extremity function was Hedges's g=0.390 (95% CI: 0.192~0.587) (p<.05). The virtual reality program positively affects the upper extremity function of stroke patients. Therefore, the development of various virtual reality programs and industry-academia cooperation technology for stroke patients is required in accordance with the fourth industry. Randomized control trials and detailed upper extremity function studies for virtual reality programs will be needed in follow-up studies.

A Systematic Review on Studies Related to Disaster (재난관련 연구의 체계적 문헌고찰)

  • Park, Ju Young;Kim, Gaeun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.4
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    • pp.276-292
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    • 2018
  • This study was conducted to investigate the trends in domestic and international disaster-related research through a systematic review of the literature and to establish a basis for future disaster-related countermeasures and development directions. A related literature search was conducted through the domestic and foreign databases through the combination of disaster-related terms from 2000 until February 28, 2017, and 79 articles were used in the analysis based on selection and exclusion criteria of 177 total documents. As a result of the research, 31.6% of disaster research type was quantitative studies, and 29.1% of the major disciplines were medical research. In addition, there were engineering(18.9%), public administration(13.9%), and nursing(11.4%). In foreign literature, there are many triage studies for the classification of patients in multiple lesions. On the other hand, only 30.4% of total triage studies in Korea were detected. Most of them were related to triage development, triage evaluation, triage research, and reviews. In addition, according to the disaster nursing capacity framework of the International Council of Nurses, 72.3% of studies were related to the response phase. Future research on disasters requires interdisciplinary convergence, patient classification, and technology integration to improve the survival rate of multiple injuries, and an integrated system based on the results of collaborative research among interdisciplinary groups is needed.

Detection and Analysis of Post-Typhoon, Nabi Three-Dimensional Changes in Haeundae Sand Beach Topography using GPS and GIS Technology (GPS·GIS 기법을 활용한 태풍 후 해운대 해빈지형의 3차원 변화 탐지 및 분석)

  • Hong, Hyun-Jung;Choi, Chul-Uong;Jeon, Seong-Woo
    • Journal of the Korean Association of Geographic Information Studies
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    • v.9 no.3
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    • pp.82-92
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    • 2006
  • As beaches throughout Korea have suffered great losses of sand due to artificial developments and meteorological phenomena, particularly typhoons, it is necessary to monitor beaches that are prone to erosion continuously, establish and enforce a comprehensive plan to attack coastal erosion with the object of the long-term management. However, debates and temporary measures, not based on accurate coastal zone surveys and analyses, have been established up to now. Therefore, with Haeundae sand beach as a case study, we proposed methods to collect accurate spatial data of the coastline and the sand beach through GPS survey. And we detected and analyzed topographic changes resulting from Typhoon Nabi quantitatively and qualitatively, by using GIS technique. Results showed a mean elevation of 1.95 m, a total area of 53,441 $m^2$, and a total volume of 104,639 $m^3$ after Typhoon Nabi. Mean elevation rose 0.06 m between the pre- and the post-typhoon surveys by a protective shore wall. However, strong winds and north-northeast surges brought by the typhoon caused erosion of the area and the volume, by 3,096 $m^2$ and 2,320 $m^3$. Accurate spatial databases of coastal zones based on integrated GPS GIS techniques and quantitative and qualitative analyses of topographical changes will help Korea develop systematic and effective countermeasures against coastal erosion.

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Risk of Breast Cancer and Total Malignancies in Rheumatoid Arthritis Patients Undergoing TNF-α Antagonist Therapy: a Meta-analysis of Randomized Control Trials

  • Liu, Yang;Fan, Wei;Chen, Hao;Yu, Ming-Xia
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.8
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    • pp.3403-3410
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    • 2014
  • Context: Interest exits in whether TNF-alpha antagonists increase the risk of breast cancer and total malignancies in patients with rheumatoid arthritis (RA). Objectives: To analyze the risk of malignancies, especially breast cancer, in patients with RA enrolled in randomized control trials (RCTs). Methods: A systematic literature search for RCTs from 1 January 1998 to 1 July 2013 from online databases, such as PubMed, WILEY, EMBASE, ISI web of knowledge and Cochrane Library was conducted. Studies included RCTs that compared the safety of at least one dose of the five TNF-${\alpha}$ antagonists with placebo or methotrexate (MTX) (or TNF-${\alpha}$ antagonists plus MTX vs placebo plus MTX) in RA patients for more than 24 weeks and imported all the references into document management software EndNote${\times}6$. Two independent reviewers selected studies and extracted the data about study design, patients' characteristics and the type, number of all malignancies. Results: 28 RCTs from 34 records with 11,741 patients were analyzed. Of the total, 97 developed at least one malignancy during the double-blind trials, and breast cancer was observed in 17 patients (17.5% of total malignancies). However, there was no statistically significant increased risk observed in either the per protocol (PP) model (OR 0.65, 95%CI [0.22, 1.93]) or the modified intention to treat (mITT) model (OR 0.75, 95%CI [0.25, 2.21]). There were also no significant trend for increased risk of total malignancies on anti-TNF-${\alpha}$ therapy administered at approved doses in either model (OR, 1.06, 95%CI [0.64, 1.75], and OR, 1.30, 95%CI [0.80, 2.14], respectively). As to the two models, modified intention to treat model analysis led to higher estimation than per protocol model analysis. Conclusions: This study did not find a significantly increased risk of breast cancer and total malignancies in adults RA patients treated with TNF-${\alpha}$ antagonists at approved doses. However, it cannot be ignored that more patients developed malignancies with TNF-${\alpha}$ antagonists therapy compared with patients with placebo or MTX, in spite of the lack of statistical significance, so that more strict clinical trials and long-term follow-up are needed, and both mITT and PP analyses should be used in such safety analyses.

An Integrative Review on Nursing Studies Related to Humor (유머와 관련된 국내 간호연구의 통합적 고찰)

  • Kim, Shin-Jeong;Kim, Sung Hee;Lee, Jung-Eun;Kim, Hye-Young;Yoo, So Young;Oh, Jina
    • Child Health Nursing Research
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    • v.20 no.1
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    • pp.58-66
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    • 2014
  • Purpose: The purpose of this paper was to describe the attributes of nursing with humor based on an integrative review and to present basic information for developing humor intervention programs for children. Methods: Using combinations of the terms 'nursing' and 'humor' as key words, the researchers searched four electronic databases to relevant identify studies. Thirteen studies were selected through full text screening of related research published in academic journals from January 1993 to April 2013. Results: Through in-depth discussion and investigation of the relevant literature, three components emerged; 1) using instruments of coping for stress relief, 2) symptoms relief through pleasant feeling, and 3) job satisfaction and work improvement of nurse using humor. Conclusion: The results of this study suggest that humor is valuable as a nursing intervention for children and the possibility of bringing about positive results in nursing care if nurses utilize the sense of humor as fully as they can. Therefore, it is critical for nurses to develop a diversity of humor interventions for children as well as measurements to test quality and quantity of humor used in clinical pediatric settings.

A Study on the Effect of Proprioceptive Neuromuscular Facilitation Training by Meta-analysis -Focused on Balance and Gait Ability in Patients with Storke

  • Jeun, Young-Ju
    • Journal of the Korea Society of Computer and Information
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    • v.27 no.7
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    • pp.145-152
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    • 2022
  • Stroke results in balance disorders, these directly affect autonomy and gait ability. The aim of this meta-analysis was to determine the efficacy of proprioceptive neuromuscular facilitation on balance and gait. We included all randomized controlled trials assessing the efficacy of proprioceptive neuromuscular facilitation on balance and gait control in patients after stroke. This study was conducted according to the PRISMA guideline. Cochrane library, CINAHL, and PubMed were searched for studies published up to November 2021, and all randomized controlled trails(RCT) assessing PNF therapy were included. This analysis included only RCT. A total of 18 studies were selected from 1091 records obtained from the databases. The meta-analysis was performed using the R project for statistical computing version 4.0.2. The overall intervention effect was middle (standardized mean difference (SMD): 0.56) Additionally, berg balance scale (SMD: 0.48), functional reach test (SMD: 0.51), timed up and go test (SMD: 0.78), 10m walking test (SMD: 0.52), and dynamic gait index (SMD: 0.33) had medium effect sizes. The average Pedro scale was 6.63 out of 18, with a low risk of bias. These findings indicate that PNF is an effective therapy for improving balance gait in stroke patients.

Analysis of LDC Message Reception Performance of Korean eLoran Pilot Service according to Modulation Methods (첨단 지상파항법시스템(eLoran) 시범서비스의 LDC 메시지 변조기법에 따른 수신성능 분석)

  • Pyo-Woong, Son;Sak, Lee;Tae Hyun, Fang;Kiyeol, Seo
    • Journal of Navigation and Port Research
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    • v.46 no.6
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    • pp.525-529
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    • 2022
  • In the eLoran system, the Loran Data Channel (LDC) is used to provide precise timing and positioning. The LDC message can be modulated with the Eurofix method, which modulates the transmission time of the 3rd-8th pulse not used for navigation, and the 9th pulse method, which modulates data using the 9th additional pulse after the existing 8 Loran pulses. In this paper, we analyzed the reception performance of the LDC message transmitted from the eLoran transmitter according to the modulation method. The eLoran testbed transmitter in Incheon was set to transmit LDC messages simultaneously with the 9th pulse modulation method and the Eurofix modulation method. Then, the LDC messages stored in the databases of the eLoran differential stations in Incheon and Pyeongtaek were analyzed in terms of the message reception rate according to the modulation method. Using the navigation aid management ship Inseong No. 1, the range of LDC message reception of actual sea users near Incheon Port was also analyzed. The results of this study are expected to be utilized in the full operational capability service after the eLoran pilot service.