• 제목/요약/키워드: Correlation comparison

검색결과 2,803건 처리시간 0.028초

외상 환자와 비외상 환자에서 삼투압차와 에탄올 농도의 상관관계 및 추정 에탄올 농도의 정확도 (Correlation Between the Osmolar Gap and Serum Ethanol Level and the Accuracy of Estimated Ethanol Level in Trauma Patients and Non-Trauma Patients)

  • 장형우;심민섭;한상국;송형곤
    • Journal of Trauma and Injury
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    • 제22권2호
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    • pp.148-153
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    • 2009
  • Purpose: The osmolar gap increases in proportion to the ethanol level. Some previous studies have shown that the correlation between the osmolar gap and the ethanol level is weak in trauma patient by using an indirect comparison with other patients. We conducted a direct comparison of the correlation of the osmolar gap to the ethanol level between trauma patients and non-trauma patients. We also analyzed the accuracy of the estimated ethanol level between the two groups. Methods: The research candidates were adult patients who had visited the emergency department of our hospital from December 2003 to November 2008. By using a retrospective chart review, we classified them into three subgroups: non-trauma without shock, trauma without shock, and trauma with shock. In each group, we compared the correlation between the osmolar gap and the measured ethanol level, and we analyzed the accuracy of the estimated ethanol level by using Lin's concordance correlation coefficient. Results: Four hundred forty-seven patients were enrolled in this study. For correlation of the osmolar gap and the measured ethanol level, Pearson's correlation coefficient was 0.916 in all patients, 0.939 in non-trauma without shock patients, 0.917 in trauma without shock patients, and 0.844 in trauma with shock patients. In the analysis of the accuracy of the estimated ethanol level by using Lin's concordance correlation coefficient, the accuracy in trauma with shock patients was lower than that in non-trauma without shock patients. Conclusion: We found that the correlation between the osmolar gap and the measured ethanol level in the patient group with trauma was lower than it was in the patient group without trauma. Moreover trauma patients with shock had a lower accuracy of the estimated ethanol level than non-trauma patients.

AODV 라우팅 프로토콜의 성능 매트릭들 간의 상관관계 분석에 기반한 라우팅 프로토콜들 간의 성능 비교 (Performance Comparison Between Routing Protocols Based on the Correlation Analysis of Performance Metrics for AODV Routing Protocol)

  • 이윤경;김주균
    • 한국IT서비스학회지
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    • 제12권4호
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    • pp.349-367
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    • 2013
  • In MANET, the AODV routing protocol with on-demand method has a problem in large control packet overhead. In order to improve this, we first need a comprehensive analysis of correlation between performance metrics and factors affecting the performance of AODV. Selected parameters based on this analysis make it enable to be a more accurate and fair performance analysis, as well as to reduce the time and effort when constructing a scenario for performance analysis. In this paper, various scenarios are configured to apply AODV by varying the values of factors affecting the performance with network simulator QualNet 5.0, and then the results are analysed using performance metrics proposed by IETF MANET working group. This paper also founds a correlation between performance metrics and factors affecting the performance for AODV routing protocol, choosing the values of factors that represent many of the most maximum and minimum values of each performance metrics, and proposes optimal simulation parameters for a more accurate performance evaluation of routing protocols with minimal scenario in experiments. Next, performance comparison of AODV, DSR and DYMO routing protocols based on the proposed simulation parameters is shown which provides a comparative analysis on the performance of on-demand routing protocols. Results of this paper could be very useful for the researcher or service provider who wants to find nice simulation environment or select a proper routing protocol.

턱관절장애 유무에 따른 깨물근, 목빗근의 두께 및 근긴장도, 최대 입벌림 범위의 비교 및 상관성 연구 (Comparison and Correlation on Muscle Thickness and Muscle Tone of Masseter Muscle and Sternocleidomastoid Muscle, Maximum Jaw Opening in Subjects With and Without Temporomandibular Joint Disorder)

  • 이근효;천승철
    • 대한통합의학회지
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    • 제8권3호
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    • pp.93-101
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    • 2020
  • Purpose : Temporomandibular joint disorder (TMJD) is often accompanied by pain and limited range of motion of the jaw joint, which affect patients' quality of life and result in hypertrophy or hyperactivity of the muscles around the jaw joint. In this study, we compared the muscle thickness and tone of the masseter and sternocleidomastoid (SCM) muscles and the jaw range of motion in individuals with and without TMJD. Correlation comparison was performed on the results of the TMJD group. Methods : This study included 40 patients; 20 patients were assigned to an experimental group (TMJD group) and 20 to a control group (non-TMJD group). Ultrasonography, myotonometry, and measurements performed with digital Vernier calipers were used to determine the changes in muscle thickness, muscle tone, and maximum jaw opening, respectively. The independent t-test was used for intergroup comparison of data, and Pearson correlation coefficients were used to compare correlations in the TMJD group results. Results : We observed a significant intergroup difference in the masseter and SCM thickness during the relaxed and clenched phases (p<.05). A significant intergroup difference was also observed in maximum jaw opening (p<.05). With regard to muscle tone, we observed a significant intergroup difference in frequency (p=.011) and stiffness (p=.011) of the masseter, as well as in the frequency (p=.009) and stiffness (p=.026) of the SCM. We observed a moderate negative correlation (r=-.524) between maximum jaw opening and the frequency of the masseter. Additionally, we observed a moderately negative correlation between jaw opening and muscle stiffness (r=-.321). Conclusion : Planning exercise programs to treat patients with TMJD who present with pain should focus on efforts to reduce muscle thickness and achieve muscle relaxation (to reduce muscle tension) for improved jaw range of motion.

변동경향성 제거 전후의 수리지질학적 시계열분석 결과 비교 (Comparison of Hydrogeological Time Series Analysis Results Before and After Detrending)

  • 임홍균;최현미;이진용
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제16권2호
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    • pp.30-40
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    • 2011
  • In this study, we compared the analysis results before and after the detrending for the data. According to the comparison results, correlation functions were not much changed while autocorrelation and spectral density functions were largely varied. Especially, time series data with a long-term variation trend showed a distinctive difference. This study demonstrated a usefulness of the detrending for a further analysis.

Comparison of Sleep Parameter according to Apnea-Hypopnea Index

  • Jin, Bok-Hee
    • 대한임상검사과학회지
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    • 제44권4호
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    • pp.205-209
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    • 2012
  • Obstructive sleep apnea (OSA) is the most common type of sleep apnea and is caused by obstruction of the upper airway. It is characterized by repetitive pauses in breathing during sleep despite the effort to breathe. Apnea is closely related to clinical findings and respiratory disturbance index (RDI). The total subjects were 42 (male 26, female 16) and examined by polysomography (PSG) in terms of RDI above 5 and below 5 at Mok-Dong Hospital in Ewha Womans University from January to June, 2012. The study revealed the followings: The comparison of clinical findings and RDI above 5 showed significant increase in age, BMI, and snoring sound although lowest $SpO_2$ level decreased. The correlation coefficient analysis between clinical findings and RDI showed statistically significant correlation in age, BMI, lowest $SpO_2$ although snoring sound and average $SpO_2$ showed statistically insignificant correlation.

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Comparison of Daily Soil Water Contents Obtained by Energy Balance-Water Budget Approach and TDR

  • Rim, Chang-Soo
    • Korean Journal of Hydrosciences
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    • 제8권
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    • pp.57-68
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    • 1997
  • The daily soil water contents were obtained from the time domain reflectometry(TDR) method and energy balance-water budget approach with eddy correlation at the two small semiarid watersheds of Lucky Hills and Kendall during the summer rainy period. There was a comaprison of daily soil water content measured and estimated from these two different approaches. The comparison is valuable to evaluate the accuracy of current soil water content measuring system using TDR and energy balance-water budget approach using eddy correlation method at a small watershed scale. The degree of simiarity between the regressions of these two methods of measuring soil water content was explained by determining the correlations between these methods. Simple linear regression analyses showed that soil water content measured from TDR method was responsible for 58% and 63% of the variations estimated from energy balance-water budget approach with edy correlation at Lucky Hills and Kendall, respectively. The scatter plots and the regression analyses revealed that two different approaches for soil water content measurement at a small watershed scale have no significant difference.

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Type C의 연구 (Clinical study of Type C in Impedance Audiometry)

  • 김동환;소진명
    • 대한기관식도과학회:학술대회논문집
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    • 대한기관식도과학회 1977년도 제11차 학술대회연제 순서 및 초록
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    • pp.5.1-5
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    • 1977
  • 1946년 Metz가 처음으로 acoustic impedance bridge를 창안한 이후 많은 발전을 거듭하며 지금은 임상에 널리 이용되고 있으며 청각학에 많은 공헌을 하고 있다 우리나라에서도 이제 한국인의 정상치를 비롯한 많은 실험적 연구가 계속되고 있다. 저자는 본원에서 사용하고 있는 teledyne impedance (Model TA-ID)를 이용하여 나타난 Type C 때의 다음의 상관관계, 1. 이경소견과의 비교 2. 순음청력 역치와의 관계 3. Stapedial reflex와의 관계 4. 중이강내 압력과 참출물과의 상관관계 등을 조사하여 문헌고찰과 함께 보고하는 바이다.

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한국인 더미모델을 이용한 시트진동 시뮬레이션과 실차시험의 비교분석 (Comparison of Vehicle Experiment and Computer Simulation of Seat Vibration using Korean Dummy Model)

  • 유완석;김정훈;박동운;이순영
    • 한국자동차공학회논문집
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    • 제12권1호
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    • pp.145-152
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    • 2004
  • This paper compares seat vibrations of a small passenger car and a SUV. The results also include the comparison of the human body accelerations and the ride values, such as the component ride values, and SEAT values of 12 axis accelerations obtained at the human body and seat track. The ride comfort evaluation is usually carried out by experiments of real cars which are expensive and sometimes may contain errors by passenger's postures. Simulations by computer, on the other hand, enable to solve these problems when the accuracy is proven. This paper, thus, also shows the correlation of human body vibration between experiments and computer simulations. For the computer simulation, korean dummy models are developed from the Hybrid III models by scaling the body data of Hybrid III to those of Korean men and women. From the comparison between the test data and simulation data, a nice correlation in trends was shown.

Simulation Models for Investigation of Multiuser Scheduling in MIMO Broadcast Channels

  • Lee, Seung-Hwan;Thompson, John S.
    • ETRI Journal
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    • 제30권6호
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    • pp.765-773
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    • 2008
  • Spatial correlation is a result of insufficient antenna spacing among multiple antenna elements, while temporal correlation is caused by Doppler spread. This paper compares the effect of spatial and temporal correlation in order to investigate the performance of multiuser scheduling algorithms in multiple-input multiple-output (MIMO) broadcast channels. This comparison includes the effect on the ergodic capacity, on fairness among users, and on the sum-rate capacity of a multiuser scheduling algorithm utilizing statistical channel state information in spatio-temporally correlated MIMO broadcast channels. Numerical results demonstrate that temporal correlation is more meaningful than spatial correlation in view of the multiuser scheduling algorithm in MIMO broadcast channels. Indeed, the multiuser scheduling algorithm can reduce the effect of the Doppler spread if it exploits the information of temporal correlation appropriately. However, the effect of spatial correlation can be minimized if the antenna spacing is sufficient in rich scattering MIMO channels regardless of the multiuser scheduling algorithm used.

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Comparison of postoperative paresthesia after sagittal split osteotomy among different fixation methods: a one year follow-up study

  • Tabrizi, Reza;Bakrani, Kousha;Bastami, Farshid
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제45권4호
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    • pp.215-219
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    • 2019
  • Objectives: Postoperative paresthesia is a common complication after sagittal split osteotomy (SSO). This study aimed to compare paresthesia among different fixation methods one year postoperative. Materials and Methods: This prospective cohort study assessed subjects in four groups: class II with miniplate fixation (Group 1), class II with three-screw fixation (Group 2), class III with miniplate fixation (Group 3), and class III with three-screw fixation (Group 4). Paresthesia was evaluated one year postoperative based on a 0-10 visual analogue scale. Pearson correlation was used to evaluate associations of age and mandibular movement with paresthesia. ANOVA was used to compare paresthesia among groups. Results: A total of 80 subjects were enrolled, with 20 subjects in each of the four groups. The Pearson correlation test demonstrated a significant correlation between mandibular movement and paresthesia (P=0.001). Comparison of paresthesia among the groups showed significant differences among groups 1 and 2, 2 and 3, and 3 and 4 (P<0.05). Conclusion: The three-screw fixation method led to more paresthesia one year postoperative compared with miniplate fixation. In addition, the magnitude of mandibular movement had a positive correlation with paresthesia.