• Title/Summary/Keyword: inaccuracy

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TFRC Flow Control Mechanism based on RTP/RTCP for Real-time Traffic Transmission (실시간 트래픽 전송을 위한 RTP/RTCP의 TFRC 흐름제어 기법)

  • Choi, Hyun-Ah;Song, Bok-Sob;Kim, Jeong-Ho
    • The Journal of the Korea Contents Association
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    • v.8 no.8
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    • pp.57-64
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    • 2008
  • In this paper, to resolve the problem caused by a network state information inaccuracy the slow delay time that conclusion of network state of one way delay time which accuracy delay time information, according to network state changes on the based TFRC flow control, and suggest that flow control mechanism to adjust transfer rate fit of real time multimedia data. In simulation, to measure of netowork state information that on the average about 12% difference of compared RTT and $OWD{\times}2$. When used RTT, used fair bandwidth TFRC much better than TCP about 32%, when used OWD, difference about 3% used fair bandwidth. Thus, conclusion of accuracy network state that used fair bandwidth according to network state changes on the based TFRC, users can support service of high quality that flow control mechanism to adjust transfer rate fit of real time data.

Transesterification of Dimethyl Terephthalate with Diethylene Glycol (Dimethyl terephthalate와 diethylene glycol의 에스테르 교환 반응)

  • Kim, Gunhyung;Cho, Minjeong;Jeon, Yeonghwan;Han, Myungwan;Kang, Kyungsuk
    • Korean Chemical Engineering Research
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    • v.53 no.2
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    • pp.253-261
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    • 2015
  • The kinetics of the transesterification of dimethyl terephthalate (DMT) with diethylene glycol (DEG) was studied in a batch reactor. bis-hydroxyethoxytethyl-terephthalate (BHEET), which is polyester polyol monomer, can be produced by the transesterification reaction. Zinc acetate was used as a catalyst. Previous kinetic studies was carried out in a semi-batch reactor where generated methanol was removed so that reverse reactions were not considered in the kinetic expressions, resulting in inaccuracy of the kinetic model. Mathematical models of a batch reactor for the tranesterification reaction, which took the reverse reaction into account, were developed and used to characterize the reaction kinetics and the composition distribution of the reaction products. More accurate models than previous ones were obtained and found to have a good agreement between model predictions and experimental data. Effect of process variables on the esterification reaction was investigated based on the experimental and simulation results.

Stock market stability index via linear and neural network autoregressive model (선형 및 신경망 자기회귀모형을 이용한 주식시장 불안정성지수 개발)

  • Oh, Kyung-Joo;Kim, Tae-Yoon;Jung, Ki-Woong;Kim, Chi-Ho
    • Journal of the Korean Data and Information Science Society
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    • v.22 no.2
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    • pp.335-351
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    • 2011
  • In order to resolve data scarcity problem related to crisis, Oh and Kim (2007) proposed to use stability oriented approach which focuses a base period of financial market, fits asymptotic stationary autoregressive model to the base period and then compares the fitted model with the current market situation. Based on such approach, they developed financial market instability index. However, since neural network, their major tool, depends on the base period too heavily, their instability index tends to suffer from inaccuracy. In this study, we consider linear asymptotic stationary autoregressive model and neural network to fit the base period and produce two instability indexes independently. Then the two indexes are combined into one integrated instability index via newly proposed combining method. It turns out that the combined instability performs reliably well.

A Subway Arrival Notification System Using iBeacon (iBeacon을 이용한 지하철 도착 알림 시스템)

  • Jung, Hyun-Hee;Nam, Choon-Sung;Shin, Dong-Ryeol
    • Journal of KIISE
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    • v.42 no.2
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    • pp.272-279
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    • 2015
  • Concurrent with the more widespread usage of smart devices, mobile users' desires are becoming much more complex. Most IT experts insist that smart devices should have additional functions to satisfy these requirements. In particular, research has concentrated on LBS (Locationbased Service), because it is considered one of the most common mobile service types. Generally, Wi-Fi has a critical limitation for use for LBS services, because it requires new network connection points whenever its location (Network Zone) changes. Unfortunately, GPS also has a systematic problem in providing LBS service in the indoor environment, because of its inaccuracy in processing data. So, to redress these limitations, iBeacon technology has been designed, and is currently used for LBS service instead of Wi-Fi or GPS. By using iBeacon, which is based on Bluetooth 4.0 LE technology, we propose a M-SAS (Mobile-Subway-Alarm-Service System) that could accurately and timely provide its users with various mLBS (micro LBS) services, such as current user location, and subway arrival time.

A Path Prediction-Based Sensor Registry System for Stable Use of Sensor Information (센서 정보의 안정적인 이용을 위한 경로 예측 기반 센서 레지스트리 시스템)

  • Jeong, Dongwon;Doo, Migyeong
    • Journal of KIISE
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    • v.42 no.2
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    • pp.255-263
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    • 2015
  • The sensor registry system has been developed for instant use and seamless interpretation of sensor data in a heterogeneous sensor network environment. However, the existing sensor registry system cannot provide information for interpretation of the sensor data in situations in which the network is unstable. This limitation causes several problems such as sensor data loss, inaccuracy of processed results, and low service quality. A method to resolve such problems in the aspect of software is presented herein. In other words, an extended sensor registry system is proposed to enable the stable use of sensor information, even under conditions of unstable network connection, by providing sensor information with a mobile device in advance through the user path prediction. The results of experiments and evaluation are also presented. The extended sensor registry system proposed in this paper enhances the stable usability of sensor information as well as improves the quality of sensor-based services.

Literature Review on the Current Status of Herbal Medicine Use as Topical Anesthetics (한약의 국소 외용 마취제 활용 현황에 대한 문헌 고찰)

  • Song, Min-A;Hong, Young-Ju;Seo, Hyung-Sik
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.33 no.4
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    • pp.114-125
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    • 2020
  • Objectives : The aim of this study is to review the topical anesthetic effect of herbal medicine. Methods : Using domestic database(OASIS, RISS) and foreign database(Pubmed, Embase, Cochrane library, CNKI), clinical studies about efficacy of herbal medicine as topical anesthetics were searched. Only randomized controlled trials(RCT) were selected and analyzed. Results : Total 647 studies were searched. After screening process, 5 articles were selected. 2 were from Chinese database and 3 were from English database. Articles were about clinical use of herbal medicine as topical anesthetics and compare their efficacy with conventional topical anesthetics. Out of 5 articles, 4 articles used pain rating scales recorded by subjects as outcome measurement. All studies showed lower pain score in herbal medicine using groups. 4 studies showed that there was no statistically significant difference in pain score between herbal medicine using group and conventional topical anesthetics using group. Conclusions : The results suggest that topical anesthetics using herbal medicine is as effective as or maybe even more effective than conventional topical anesthetics. However, experimental design and composition of intervention were all different, which provides inaccuracy when comparing the experimental results. Also, sample sizes were small and the number of RCTs were insufficient to identify full list of herbs that have potentials to be used topical anesthetics. Further studies need to be conducted to find out potentials of herbal medicine as topical anesthetics.

Improvement of Cost-Schedule integration based Progress Management through PMIS (비용-일정통합기반 진도관리 개선방안)

  • Yoon, You-Sang;Suh, Sang-Wook;Jang, Gyu-Seong;Choi, Jang-Shik
    • Korean Journal of Construction Engineering and Management
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    • v.14 no.5
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    • pp.144-152
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    • 2013
  • Recently construction projects become more bigger. So construction companies have being performed cost and schedule management task by using PMIS. In engineering and construction phase, progress management which occur the most frequent information I/O(input and output) should be managed effectively by PMIS. Although most information by PMIS manage efficiently, cost-schedule information for progress management is difficult to be managed due to recurrent information input. thus when changed by price fluctuation and change order, progress management could not connnect cost information with schedule information. So it caused inaccuracy of progress measurement and data increase in PMIS. To solve this problem, This study suggests improved module for progress management through integration of cost-schedule using quantity take-offs as progress measurement method.

Incidence of Liver Function Test Abnormality among Patients Hospitalized in an Oriental Hospital (한방병원에 입원한 환자군에서 간기능 검사 이상자의 빈도 조사)

  • Han, Chang-Woo;Kim, Su-Young;Min, Kwan-Sik;Lee, Jin-Hyuk;Lee, Sang-Ho;Youn, You-Suk
    • The Journal of Korean Medicine
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    • v.31 no.2
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    • pp.109-113
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    • 2010
  • Objectives: Liver function tests are used as screening tests for liver injuries, but their inaccuracy on positive predictive values can result in numerous false positive results. We investigated the incidence of liver function test abnormalities of patients who came to an oriental medicine hospital, in order to present a practical way to rule out false positive results for other studies designed to investigate the safety of Korean herb medicine. Methods: We analyzed the medical records and liver function test results proceeded at admission of all in-patients admitted to Jaseng Oriental Medicine Hospital, from July 2008 to June 2009. Results: Among 1,117 inpatients, 941 executed liver function tests on admission, and 40 were excluded due to their diagnosed liver disease. 747 (82.9%) of 901 enrolled patients were within the normal range of all liver function tests, and 140 (15.5%) and 14 (1.6%) were classified as "abnormalities of liver tests" and "liver injury" respectively, according to the CIOMS (Council for International Organizations of Medical Sciences) criteria. Conclusions: According to the results, among the outcomes of liver function tests proceeded among the patients admitted to the oriental medicine hospital, excluding who were diagnosed with liver disease, 17.1% showed abnormality. This means simple liver function test results are not sufficient in determining liver toxicity of Korean herb medicine (KHM).

Localization of primary user for cognitive radios based on estimation of path-loss exponent (인지무선시스템을 위한 전송 손실 지수 추정 기반의 기 사용자 위치 검출 기법)

  • Anh, Hoang;Koo, Insoo
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.13 no.5
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    • pp.55-63
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    • 2013
  • In cognitive radio networks, acquirement of position information of primary user is very important to secondary network since localization information of primary users can be utilized for improving the spectrum efficiency of secondary network and for avoiding harmful interference to primary users by using proper power control. Among various location methods, Received Signal Strength (RSS)-based localization has been widely used for distance measurements in the location detection process despite its inherent inaccuracy because it can be easily implemented without any additional hardware cost. In the RSS-based localization, the distance is measured by the received signal strength, and distance error can be caused by many factors such as fading, shadowing and obstacle between two nodes. In the paper, therefore we propose a localization scheme based on estimation of path-loss exponent to localize the location of primary users more accurately. Through simulations, it is shown that the proposed scheme can provide less localization error and interference rate to primary users than other schemes.

Development of Experience System for Sasang Constitution Analysis (사상체질 분석 체험 시스템 개발)

  • So, Ji-Ho;Jeon, Young-Ju
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.20 no.5
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    • pp.9-13
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    • 2020
  • Sasang Constitutional Medicine is a traditional Korean medicine optimized for personalized medicine, and despite its effective clinical efficacy, the inaccuracy of constitutional diagnosis has been pointed out as a limitation. To improve the accuracy, a constitutional analysis algorithm based on quantitative data was developed. In this study, a constitutional analysis experience system applied with the algorithm was developed and repeatability was evaluated. The system analyzes the constitution of the experiencer by collecting front and side facial images, audio, and questionnaire and calculating the integrated constitution probability value. To evaluate the repeatability of the probability values of the system was performed five times each for three people, and the coefficient of variation was 4.778%, indicating that the repeatability was sufficient. The system could contribute to the promotion of the awareness of Sasang medicine.