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1.
Sensors (Basel) ; 24(4)2024 Feb 06.
Article in English | MEDLINE | ID: mdl-38400212

ABSTRACT

This research delves into advancing an ultra-wideband (UWB) localization system through the integration of filtering technologies (moving average (MVG), Kalman filter (KF), extended Kalman filter (EKF)) with a low-pass filter (LPF). We investigated new approaches to enhance the precision and reduce noise of the current filtering methods-MVG, KF, and EKF. Using a TurtleBot robotic platform with a camera, our research thoroughly examines the UWB system in various trajectory situations (square, circular, and free paths with 2 m, 2.2 m, and 5 m distances). Particularly in the square path trajectory with the lowest root mean square error (RMSE) values (40.22 mm on the X axis, and 78.71 mm on the Y axis), the extended Kalman filter with low-pass filter (EKF + LPF) shows notable accuracy. This filter stands out among the others. Furthermore, we find that integrated method using LPF outperforms MVG, KF, and EKF consistently, reducing the mean absolute error (MAE) to 3.39% for square paths, 4.21% for circular paths, and 6.16% for free paths. This study highlights the effectiveness of EKF + LPF for accurate indoor localization for UWB systems.

2.
J Korean Neurosurg Soc ; 46(4): 333-9, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19893722

ABSTRACT

OBJECTIVE: Few studies on the clinical spectrum of automated pressure-controlled discography (APCD)-defined positive discs have been reported to date. Thus, the present study was undertaken to analyze clinical parameters critical for diagnosis of discogenic pain and to correlate imaging findings with intradiscal pressures and pain responses in patients with APCD-positive discs. METHODS: Twenty-three patients who showed APCD-positive discs were selected for analysis. CT discogram findings and the degrees of nuclear degeneration seen on MRI were analyzed in comparison to changes of intradiscal pressure that provoked pain responses; and clinical pain patterns and dynamic factors were evaluated in relation to pain provocation. RESULTS: Low back pain (LBP), usually centralized, with diffuse leg pain was the most frequently reported pattern of pain in these patients. Overall, LBP was most commonly induced by sitting posture, however, standing was highly correlated with L5/S1 disc lesions (p < 0.01). MRI abnormalities were statistically correlated with grading of CT discogram results (p < 0.05); with most pain response observed in CT discogram Grades 3 and 4. Pain-provoking pressure was not statistically correlated with MRI grading. However, it was higher in Grade 3 than Grade 4. CONCLUSION: APCD-positive discs were demonstrated in patients reporting centralized low back pain with diffuse leg pain, aggravated by sitting and standing. MRI was helpful to assess the degree of nuclear degeneration, yet it could not guarantee exact localization of the painful discs. APCD was considered to be more useful than conventional discography for diagnosis of discogenic pain.

3.
J Korean Med Sci ; 23(6): 1005-10, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19119444

ABSTRACT

Few studies have been conducted to explain the pain patterns resulting from osteoporotic vertebral compression fractures (OVCF). We analyzed pain patterns to elucidate the pain mechanism and to provide initial guide for the management of OVCFs. Sixty-four patients underwent percutaneous vertebroplasty (N=55) or kyphoplasty (N=9). Three pain patterns were formulized to classify pains due to OVCFs: midline paravertebral (Type A), diffuse paravertebral (Type B), and remote lumbosacral pains (Type C). The degree of compression was measured using scale of deformity index, kyphosis rate, and kyphosis angle. Numerical rating scores were serially measured to determine the postoperative outcomes. As vertebral body height (VBH) decreased, paravertebral pain became more enlarged and extended anteriorly (p<0.05). Type A and B patterns significantly showed the reverse relationship with deformity index (p<0.05), yet Type C pattern was not affected by deformity index. Postoperative pain severity was significantly improved (p<0.05), and patients with a limited pain distribution showed a more favorable outcome (p<0.05). The improvement was closely related with the restoration of VBH, but not with kyphosis rate or angle. Thus, pain pattern study is useful not only as a guide in decision making for the management of patients with OVCF, but also in predicting the treatment outcome.


Subject(s)
Fractures, Compression/surgery , Osteoporosis/complications , Pain/surgery , Spinal Fractures/surgery , Aged , Aged, 80 and over , Female , Fracture Fixation, Internal/methods , Fractures, Compression/diagnostic imaging , Fractures, Compression/etiology , Humans , Kyphosis/therapy , Magnetic Resonance Imaging , Male , Middle Aged , Osteoporosis/diagnosis , Pain/etiology , Pain Measurement , Pain, Postoperative/etiology , Polymethyl Methacrylate/administration & dosage , Polymethyl Methacrylate/therapeutic use , Sickness Impact Profile , Spinal Fractures/diagnostic imaging , Surveys and Questionnaires , Tomography, X-Ray Computed , Treatment Outcome
4.
J Korean Med Sci ; 21(5): 911-6, 2006 Oct.
Article in English | MEDLINE | ID: mdl-17043428

ABSTRACT

Discogenic pain is a leading cause of chronic low back pain. The authors investigated the efficacy of pressure-controlled discography to determine its role in clinical decision-making for the management of patients with discogenic pain. Pressure-controlled discography was performed in 21 patients (51 discs) with pain-provocation, followed by post-discography computerized tomography scans. Pain response was classified as positive response and negative response, and measured with visual analog scale scores. Discographic findings were graded by the modified Dallas discogram scale. Elastance, pain provocation on intradiscal pressure, pressure and volume of initial pain response, and pain response intensity were statistically analyzed. Elastance showed significant differences between Grade 0 and Grade 4 and 5. Decreased elastance with positive pain response group was a good indicator to imply that disc degeneration presumably is a pain generator. Results of pain response were well correlated with intradiscal pressure but not with the amount of injected volume. Among 31 discs of Grade 4 and 5, 74% showed negative pain response and 26% showed positive response. It was concluded that pressure-controlled discography was useful to diagnose discogenic pain and excellent guide in decision-making for spinal operations.


Subject(s)
Intervertebral Disc/diagnostic imaging , Low Back Pain/diagnostic imaging , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Pain Measurement , Pressure , Tomography, X-Ray Computed
5.
J Korean Med Sci ; 21(1): 119-25, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16479077

ABSTRACT

Chronic neck and arm pain or cervicobrachialgia commonly occurs with the degeneration of cervical spine. Authors investigated the usefulness of radiofrequency (RF) neurotomies of cervical medial branches in patients with cervicobrachialgia and analyzed the factors which can influence the treatment outcome. Demographic data, types of pain distribution, responses of double controlled blocks, electrical stimulation parameters, numbers and levels of neurotomies, and surgical outcomes were evaluated after mean follow-up of 12 months. Pain distribution pattern was not significantly correlated with the results of diagnostic blocks. Average stimulation intensity was 0.45 V, ranging from 0.3 to 0.69, to elicit pain response in cervical medial branches. The most common involvement of nerve branches was C4 (89%), followed by C5 (82%), C6 (75%), and C7 (43%). Among total of 28 patients, nineteen (68%) reported successful outcome according to outcome criteria after 6 months of followup (p=0.001), and eight (42%) of 19 patients reported complete relief (100%) of pain. Four patients showed recurrence of pain between 6 and 12 months. It was therefore concluded that cervical medial branch neurotomy is considered useful therapeutic modality for the management of cervicobrachialgia in selected patients, particularly in degenerative zygapophyseal disorders.


Subject(s)
Brachial Plexus Neuritis/surgery , Brachial Plexus/surgery , Neurosurgical Procedures/methods , Adult , Aged , Aged, 80 and over , Back Pain/etiology , Back Pain/surgery , Brachial Plexus/pathology , Brachial Plexus Neuritis/complications , Brachial Plexus Neuritis/diagnosis , Chronic Disease , Electrosurgery/methods , Female , Humans , Male , Middle Aged , Neck Pain/etiology , Neck Pain/surgery , Nerve Block/methods , Neurosurgical Procedures/instrumentation , Treatment Outcome
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