• Title/Summary/Keyword: Time interval measurement

Search Result 286, Processing Time 0.028 seconds

Automated Measurement of Native T1 and Extracellular Volume Fraction in Cardiac Magnetic Resonance Imaging Using a Commercially Available Deep Learning Algorithm

  • Suyon Chang;Kyunghwa Han;Suji Lee;Young Joong Yang;Pan Ki Kim;Byoung Wook Choi;Young Joo Suh
    • Korean Journal of Radiology
    • /
    • v.23 no.12
    • /
    • pp.1251-1259
    • /
    • 2022
  • Objective: T1 mapping provides valuable information regarding cardiomyopathies. Manual drawing is time consuming and prone to subjective errors. Therefore, this study aimed to test a DL algorithm for the automated measurement of native T1 and extracellular volume (ECV) fractions in cardiac magnetic resonance (CMR) imaging with a temporally separated dataset. Materials and Methods: CMR images obtained for 95 participants (mean age ± standard deviation, 54.5 ± 15.2 years), including 36 left ventricular hypertrophy (12 hypertrophic cardiomyopathy, 12 Fabry disease, and 12 amyloidosis), 32 dilated cardiomyopathy, and 27 healthy volunteers, were included. A commercial deep learning (DL) algorithm based on 2D U-net (Myomics-T1 software, version 1.0.0) was used for the automated analysis of T1 maps. Four radiologists, as study readers, performed manual analysis. The reference standard was the consensus result of the manual analysis by two additional expert readers. The segmentation performance of the DL algorithm and the correlation and agreement between the automated measurement and the reference standard were assessed. Interobserver agreement among the four radiologists was analyzed. Results: DL successfully segmented the myocardium in 99.3% of slices in the native T1 map and 89.8% of slices in the post-T1 map with Dice similarity coefficients of 0.86 ± 0.05 and 0.74 ± 0.17, respectively. Native T1 and ECV showed strong correlation and agreement between DL and the reference: for T1, r = 0.967 (95% confidence interval [CI], 0.951-0.978) and bias of 9.5 msec (95% limits of agreement [LOA], -23.6-42.6 msec); for ECV, r = 0.987 (95% CI, 0.980-0.991) and bias of 0.7% (95% LOA, -2.8%-4.2%) on per-subject basis. Agreements between DL and each of the four radiologists were excellent (intraclass correlation coefficient [ICC] of 0.98-0.99 for both native T1 and ECV), comparable to the pairwise agreement between the radiologists (ICC of 0.97-1.00 and 0.99-1.00 for native T1 and ECV, respectively). Conclusion: The DL algorithm allowed automated T1 and ECV measurements comparable to those of radiologists.

Soil Evaporation Evaluation Using Soil Moisture Measurements at a Hillslope on a Mountainous Forest (산림 사면에서 실측 토양수분을 이용한 토양증발평가)

  • Gwak, Yong-Seok;Kim, Sang-Hyun
    • Journal of Korea Water Resources Association
    • /
    • v.45 no.6
    • /
    • pp.557-568
    • /
    • 2012
  • In order to understand the hydrological processes on the mountainous forest, the configuration of soil evaporation (E) out of evapotranspiration (ET) is a challenging and important topic. In this study, we attempted to understand the soil evaporation process for a humid forest hillslope via measuring and analyzing soil moistures with a sampling interval in 2 hours at three locations for 10 days between May 22th and 31th 2009. Two methods were used to estimate soil evaporation in every 2hr; one is a method using soil moisture measurement ($E_{SM}$), the others methods are based on Penman equation (Penman (1948), Staple (1974), Konukcu (2007), Equilibrium Penman ($E_{equili}$)). As a critical parameter in determining $E_{SM}$, the dry surface layer (DSL), was estimated using energy balance equation. The accumulated soil evaporation ($E_{SM}$) of A, B, C points were estimated as 2.09, 1.08 and 2.88 mm, respectively. The estimated evaporation of Penman (1948), Staple (1974), Konukcu (2007), $E_{equili}$ were 4.91, 8.80, 8.63 and 3.28 mm. The proposed method with soil moisture measurement showed lower soil evaporations than the other conventional methods. The increasing soil temperature and interaction between soil and atmosphere due to existence of litter and DSL are considered as dominant factors for soil evaporation. The $E_{SM}$ has the apparent lag time between 2 and 4 hr compared with $E_{equili}$ and net radiation. The DSL and surface resistance ($r_s$) were increased as soil moisture was decreased for in this study. The estimated DSL through the temporal distribution analysis of soil moisture and tension measurements was also similar to that of the energy balance relationship.

COMPARATIVE EXPERIMENTAL STUDY ON MEASUREMENT OF ORAL TEMPERATURE WITH DIFFERENT KINDS OF CLINICAL THERMOMETERS -comparison of Oral Temperature and Oral Placement Time among Fahrenheit Glass Thermometer, Electric Thermometer, Yu II centigrade Glass Thermometer, and Kuk II centigrade Glass Thermometer- (각종 체온계의 구강체온측정에 관한 실험적 비교연구 -외제화씨 체온계, 전자체온계 및 국산 섭씨체온계에 의한 측정온도와 측정시간의 비교-)

  • 윤정숙
    • Journal of Korean Academy of Nursing
    • /
    • v.4 no.2
    • /
    • pp.93-106
    • /
    • 1974
  • The purposes of this study are to identify the necessity of utilization of electric thermometer, to determine the difference of clinical thermometers to reach maximum or optimum temperature, and to determine the length of time necessary for temperature taking, with Fahrenheit thermometer, electric thermometer, Yu Ⅱ centigrade thermometer, and Kuk ll centigrade thermometer. The first and second comparative Experiments were' conducted from August 25 through September 30, 1973. In the first experiment, Fahrenheit thermometer, which had been accurately teated two times, and electric thermometer have been utilized. These two kinds of thermometers were inserted simultaneously under the central area of the tongue and the mouth kept closed while thermometers were in place. All temperature readings were done at one minute interval until leaching-maximum temperature. These procedures were repeated one hundred times and the data were-analyzed statistically by means of the t-test. In the second experiment, Fahrenheit thermometer, which had been accurately tested two. times, Yu Ⅱ centigrade thermometer, and Kuk Ⅱ centigrade thermometer have been utilized. These three kinds of thermometers were inserted simultaneously under the central area of the. tongue and the mouth kept closed while thermometer were in place. All temperature readings were done at one minute interval until reaching maximum temperature. These procedures were. repeated one hundred times and the data were analyzed statistically by means of the F-ratio Under the eight hypotheses designed for this study, the findings obtained are as follows: 1. There were no significant differences in the maximum temperature between Fahrenheit thermometer and electric thermometer. The mean maximum temperature for Fahrenheit thermometers was 37.06℃ and for electric thermometer was 37.09℃. 2. The placement time to reach maximum temperature taken by Fahrenheit thermometer was significantly shorter than that by electric thermometer. The mean placement time for Fahrenheit thermometers was 4.04 minutes, for electric thermometer was 5.52 minutes. In the case of Fahrenheit thermometers, 45 to 77 percent after 3 to 5 minutes, over 90 Percent after 7 minutes, and 100 percent after 10 minutes, had reached optimum temperature. When the electric thermometer was used, 23 to 54 percent after 3 to 5 minutes, over 90 percent after 9 minutes, and 100 percent after 12 minutes, had reached optimum temperature. 5. There ware no significant differences in the maximum temperature among Fahrenheit thermometer, Yu Ⅱ centigrade thermometer, and Kuk Ⅱ centigrade thermometer. The mean maximum temperature for Fahrenheit thermometers was 36.67℃, for Yu Ⅱ centigrade thermometer, was 33.73℃, and for Kuk Ⅱ centigrade thermometers was 37.76℃. 6. There were no significant differences in placement time to reach maximum temperature among Fahrenheit thermometer, Yu Ⅱ centigrade Thermometer, and Kuk Ⅱ centigrade thermometer. The mean placement time (or Fahrenheit thermometers was 7.77 minutes, for Yu Ⅱ centigrade thermometers was 7.25 minutes, and Kuk Ⅱ centigrade thermometers was 7.25 minutes. In the case of Fahrenheit thermometers, 8 to 24 percent after 3 to 5 minutes, over 90 percent after 11 minutes, and 100 percent after 13 minutes, had reached maximum temperature. When the Yu Ⅱ centigrade thermometer was used, 10 to 27 percent after 3 to 5 minutes, over 90 percent after 11 minutes, an8 103 percent after 13 minutes, had reached maximum temperature. When the Kuk Ⅱ centigrade thermometer was used, 11 to 27 Percent after 3 to 5 minutes, over 90 percent after 11 minutes, and 100 percent after 12 minutes, had reached maximum temperature. 7. There were no significant differences in the optimum temperature(the maximum temperature minus 0.1℃) among fahrenheit thermometer, Yu Ⅱcentigrade thermometer, and Kuk Ⅱ centigrade thermometer. The mean optimum temperature for Fahrenheit thermometers was 36.60℃, for Yu Ⅱ centigrade thermometers was 36.69℃, and Kuk Ⅱ centigrade thermometers was 36.69℃. 8. There were no significant differences in placement time to reach optimum temperature among Fahrenheit thermometer, Yu Ⅱ centigrade thermometer, and Kuk Ⅱ centigrade thermometer The mean placement time for Fahrenheit thermometers was 5.70 minutes, for Yu Ⅱ centigrade thermometers was 5.54 minutes, and for Kuk Ⅱ centigrade thermometers was 5.28 minutes. In the case of Fahrenheit thermometers, 21 to 49 percent after 3 to 5 minutes, over 90 percent after 9 minutes, and 100 percent after 12 minutes, had reached optimum temperature. When the Yu Ⅱ centigrade thermometer was used, 23 to 51 percent after 3 to 5 minutes over 90 percent after 10 minutes, and 100 percent after 12 minutes, had reached optimum temperature. When the Kuk Ⅱ centigrade Thermometer was used, 23 to 57 Percent after 3 to 5 minutes, over 90 percent after 9 minutes, and 100 Precent after 11 minutes, had reached optimum temperature.

  • PDF

The Effects of Sensory Integration Intervention Combined With Auditory Perception Training on Sensory Processing, Visual Perception and Attention of Children With Developmental Delay: Single-Subject Design (청지각 훈련과 병행한 감각통합치료가 발달지연 아동의 감각처리, 시 지각 발달, 주의집중에 미치는 영향: 개별실험연구)

  • Park, Mi-Young;Lim, Young-Myung;Kim, Hee
    • The Journal of Korean Academy of Sensory Integration
    • /
    • v.15 no.2
    • /
    • pp.66-79
    • /
    • 2017
  • Objective : The purpose of this study is investigate the effects of sensory integration combined with auditory treatment on the sensory processing, visual perception and attention ability of children with developmental delay. Methods : A combined treatment of auditory training and sensory integration therapy was implemented to 3 children aged 4 to 7 and diagnosed with developmental delay during 9 weeks period from December 2016 to January 2017. ABA' design which is one of single subject research designs was used in this study. Baseline A had 4 sessions, intervention B had 15 sessions, and baseline A' had 4 sessions, so 23 sessions were applied in total. During the baseline A and A 'periods, visual perception ability was measured by K-DTVP-2 (Korea Developmental Test Visual Perception-2) and sensory processing ability was evaluated by sensory profile. The maintenance time of attention was measured with the absence of intervention for the baseline period, and for the intervention period, it was measured at 10 minutes break time which was provided after the intervention. The children's attention time during a fine motor task provided were measured using video recorder with the interval recording method, and the interval for the evaluation was 30 seconds. Results : No statistically significant difference were found in the visual perception function and sensory processing scores before and after treatment. Attention of participant A enhanced significantly while that of participant B and C did not improve significantly. Conclusion : It is hard to conclude that sensory integration therapy combined with auditory perception training has positive effects on visual perception function and attention of children with developmental delays. However, there were significant increase in attention and improvements in behavior related to sensory processing for some cases in this study. In further study, longer intervention periods and valid measurement need to be applied in order to get better results. And it is proposed that more studies need to be done to enhance evidence of auditory perception training as a mean to facilitate attention and to prepare learning.

Kinematic Effects of Newly Designed Knee-Ankle-Foot Orthosis With Oil Damper Unit on Gait in People With Hemiparesis

  • Park, Hyung-Ki;Kim, Tack-Hoon;Choi, Houng-Sik;Roh, Jung-Suk;Cynn, Heon-Seock;Kim, Jong-Man
    • Physical Therapy Korea
    • /
    • v.20 no.1
    • /
    • pp.64-73
    • /
    • 2013
  • The purposes of this study were to develop a new orthosis controlling ankle and knee joint motion during the gait cycle and to identify the effects of the newly designed orthosis on gait kinematics and tempospatial parameters, including coordination of the extremities in stroke patients. Fifteen individuals who had sustained a stroke, onset was 16 months, participated in this study. Before application of the measurement equipment the subjects were accustomed to walking on the ankle-foot orthosis (AFO) or stance control knee with knee flexion assisted-oil damper ankle-foot orthosis (SCKAFO) for 5 minutes. Fifteen patients were investigated for 45 days with a 3-day interval between sessions. Measurements were walking in fifteen stroke with hemiparesis on the 3D motion analysis system. Comparison of AFO and SCKAFO are gait pattern. The difference between the AFO and SCKAFO conditions was significant in the gait velocity, step length of the right affected side, stance time of both legs, step-length asymmetry ratio, single-support-time asymmetry ratio, ${\phi}$-thigh angle and ${\phi}$-shank angle in the mid swing (p<.001). Using a SCKAFO in stroke patients has shown similar to normal walking speeds can be attained for walking efficiency and is therefore desirable. In this study, the support time of the affected leg with the SCKAFO was longer than with the AFO and the asymmetry ratio of single support time decreased by more than with the AFO. This indicates that the SCKAFO was effective for improving gait symmetry, single-support-time symmetry. This may be due to the decrease of gait asymmetry. Thus, the newly designed SCKAFO may be useful for promoting gait performance by improving the coordination of the extremity and decreasing gait asymmetry in chronic stroke patients.

Nondestructive Evaluation of Remanent Life of Turbine Rotor Steel by Measuring Reversible Magnetic Permeability (가역투자율 측정에 의한 터빈로터강의 비파괴적 잔여수명 평가)

  • Ryu, Kwon-Sang;Nahm, Seung-Hoon;Kim, Yong-Il
    • Journal of the Korean Society for Nondestructive Testing
    • /
    • v.23 no.4
    • /
    • pp.315-321
    • /
    • 2003
  • The integrity of the turbine rotors can be assessed by measuring the material properties at service temperature. In order to evaluate the remanent life of turbine rotor steel nondestructively, a measurement system of reversible magnetic permeability using an alternating perturbing magnetic field was constructed. We present a new non-destructive method to evaluate the remanent life of 1Cr-1Mo-0.25V steel using the value of reversible magnetic permeability. This method is based on the existence of reversible magnetic permeability in the differential magnetization around the coercive field strength. We measured the first harmonics voltage induced in a coil using a lock-in amplifier tuned to an exciting frequency. The Results of reversible magnetic Permeability and Wickers hardness on the aged samples show that the peak interval of reversible magnetic permeability (PIRMP) and Vickers hardness decreases as aging time increases. A softening curve is obtained from the correlation between Vickers hardness and the PIRMP. This curve can be used as a non-destructive method to evaluate the remanent life of turbine rotor steel.

Effective PPG Signal Processing Method for Detecting Emotional Stimulus (감성 자극 판단을 위한 효과적인 PPG 신호 처리 방법)

  • Oh, Dong-Gi;Min, Byung-Seok;Kwon, Sung-Oh;Kim, Hyun-Joong
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.37 no.5C
    • /
    • pp.393-402
    • /
    • 2012
  • In this study, we propose a signal processing algorithm to measure the arousal level of a human subject using a PPG(Photoplethysmography) sensor. From the measured PPG signals, the arousal level is determined by PPI(Pulse to Pulse Interval) and discrete-time signal processing. We ran psychophysical experiments displaying visual stimuli on TV display while measuring PPG signal from a finger, where the nature landscape scenes were used for restorative effect, and the urban environments were used to stimulate the stress. However, the measured PPG signals may include noise due to subject movement and measurement error, which results in incorrect detections. In this paper, to mitigate the noise impact on stimulus detection, we propose a detecting algorithm using digital signal processing methods and statistics of measured signals. A filter is adopted to remove a high frequency noise and adaptively designed taking into account the statistics of the measured PPG signals. Moreover we employ a hysteresis method to reduce the distortion of PPI in decision of emotional. Via experiment, we show that the proposed scheme reduces signal noise and improves stimulus detection.

A study on Evaluating Validity of SNR Calculation Using a Conventional Two Region Method in MR Images Applied a Multichannel Coil and Parallel Imaging Technique (다중채널코일과 병렬영상기법 이용 시 두영역측정법을 사용한 신호대잡음비 측정의 문제점)

  • Choi, Kwan-Woo;Son, Soon-Yong;Min, Jung-Whan;Kwon, Kyung-Tae;Yoo, Beong-Gyu;Lee, Jong-Seok
    • Journal of radiological science and technology
    • /
    • v.38 no.4
    • /
    • pp.403-410
    • /
    • 2015
  • The purpose of this study was to investigate the problems of a signal to noise ratio measurement using a two region measurement method that is conventionally used when using a multi-channel coil and a parallel imaging technique. As a research method, after calculating the standard SNR using a single channel head coil of which coil satisfies three preconditions when using a two region measurement method, we made comparisons and evaluations after calculating an SNR by using a two region measurement method of which method is problematic because it is used without considering the methods recommended by reputable organizations and the preconditions at the time of using a multi-channel coil and a parallel imaging technique. We found that a two region measurement method using a multi-channel coil and a parallel imaging technique shows the highest relative standard deviation, and thus shows a low degree of precision. In addition, we found out that the difference of SNR according to ROI location was very high, and thus a spatial noise distribution was not uniform. Also, 95% confidence interval through Blend-Altman plot is the widest, and thus the conformity degree with a two region measurement method using the standard single channel head coil is low. By directly comparing an AAPM method, which serves as a standard of a performance evaluation test of a magnetic resonance imaging device under the same image acquisition conditions, an NEMA method which can accurately determine the noise level in a signal region and the methods recommended by manufacturers of a magnetic resonance imaging device, there is a significance in that we quantitatively verified the inaccurate problems of a signal to noise ratio using a two region measurement method when using a multi-channel coil and a parallel imaging technique of which method does not satisfy the preconditions that researchers could overlook.

The Measurement Of Postdischarge Patient Satisfaction Using Telephone Interview (전화를 이용한 퇴원환자 만족도 조사)

  • Song, Jung-Houp
    • Quality Improvement in Health Care
    • /
    • v.4 no.1
    • /
    • pp.104-114
    • /
    • 1997
  • Background : Hospitals(Health care providers) are under tremendous pressure to meet consumer demands in order to compete in the rapidly changing health care arena. Through evaluating patient satisfaction, hospitals(health care providers) can learn what the consumer Wants from the health care system. Timely feedback is necessary. The purpose of this study is to evaluate patients' hospital experience and satisfaction using telephone interview and to study the usefulness for telephone interview at assessing patient satisfaction. Method : The 846 patients who were discharged from September 17, 1996 to October 11, 1996 were targeted were telephoned. The informations gathered telephone survey were processed by computer and analyzed for the patient satisfaction, contributing factors. Result : The 846 patients who were discharged from September 17, 1996 to October 11, 1996 were called and 197 patients(23.3%) were successful interviewed. 51.3 percent of respondents were male and mean age is 39 years mean LOS(length of stay) is 13 days and 110(56.1%) patients were admitted by outpatients clinic. The mean calling-time is 5.5 minutes. There is no significant difference between interviewers(telemarketer) in patients satisfaction. Seven telephone interviews are possible by interview a day. There in no significant difference between groups in patients satisfaction in length of stay, path of admission, the interval between discharge and interview. 97.5 percent of respondents were satisfied with telephone interview and 81.7% were satisfied with overall satisfaction and 79.4 % of respondents were good response in interviewers' conclusion. Of six variables that were found to be correlated with telephone interview and eight variables correlated with overall hospital satisfaction, a multiple logistic regression analysis revealed that two most important variables which are significantly correlated with telephone interview are to meet doctors, not ask tediously then three variables which are with overall satisfaction are doctors explain, subject response, convenient facilities. Conclusion : The patients interviewed are satisfied with telephone interview. Telephone interview is good method for assessing patient satisfaction, making high levels of patient satisfaction and for hospital marketing.

  • PDF

Orbital Wall Reconstruction by Copying a Template (defect model) from the Facial CT in Blow-out Fracture (얼굴뼈 CT 계측 모형을 이용한 안와벽골절의 재건)

  • Kim, Jae Keun;You, Sun Hye;Hwang, Kun;Hwang, Jin Hee
    • Archives of Craniofacial Surgery
    • /
    • v.10 no.2
    • /
    • pp.71-75
    • /
    • 2009
  • Purpose: Recently, orbital wall fracture is common injuries in the face. Facial CT is essential for the accurate diagnosis and appropriate treatment to reconstruct of the orbital wall. The objective of this study was to report the method for accurate measurement of area and shape of the bony defect in the blow-out fractures using facial CT in prior to surgery. Methods: The authors experienced 46 cases of orbital wall fractures and examined for diplopia, sensory disturbance in the area of distribution of the infraorbital nerve, and enophthalmos in the preoperation and followed 1 months after surgery, from August 2007 to May 2008. Bony defect was predicted by measuring continuous defect size from 3 mm interval facial CT. Copying from the defect model (template), we reconstructed orbital wall with resorbable sheet (Inion $CPS^{(R)}$ Inion Oy, Tampere, Finland). Results: One months after surgery using this method, 26 (100%) of the 26 patients improved in the diplopia and sensory disturbance in the area of distribution of the infraorbital nerve. Also 8 (72.7%) of the 11 patients had enophthalmos took favorable turn. Conclusion: This accurate and time-saving method is practicable for determining the location, shape and size of the bony defect. Using this method, we can reconstruct orbital wall fracture fastly and precisely.