• Journal of Electrical Engineering and Technology
• /
• v.11 no.2
• /
• pp.529-536
• /
• 2016

In this paper we proposed an unsupervised algorithm to estimate the reverberation time (RT) directly from the reverberant speech signal. For estimation process we use maximum likelihood estimation (MLE) which is a very well-known and state of the art method for estimation in the field of signal processing. All existing RT estimation methods are based on the decay rate distribution. The decay rate can be obtained either from the energy envelop decay curve analysis of noise source when it is switch off or from decay curve of impulse response of an enclosure. The analysis of a pre-existing method of reverberation time estimation is the foundation of the proposed method. In one of the state of the art method, the reverberation decay is modeled as a Laplacian distribution. In this paper, the proposed method models the reverberation decay as a Gamma distribution along with the unification of an effective technique for spotting free decay in reverberant speech. Maximum likelihood estimation technique is then used to estimate the RT from the free decays. The method was motivated by our observation that the RT of a reverberant signal when falls in specific range, then the decay rate of the signal follows Gamma distribution. Experiments are carried out on different reverberant speech signal to measure the accuracy of the suggested method. The experimental results reveal that the proposed method performs better and the accuracy is high in comparison to the state of the art method.

• The Korean Journal of Pain
• /
• v.18 no.2
• /
• pp.138-141
• /
• 2005

Background: There have been many attempts to alleviate pain after surgery, but there is no common approach to the control of postoperative pain. The use of epidural opioids, with local anesthetics, has been a widely employed formula to date. Ketamine, an N-methyl-d-aspartate receptor antagonist, has an excellent analgesic effect. Although there have been many reports on the dose and route of administrating analgesics, there have been few concerning the continuous epidural infusion of ketamine with fentanyl. We designed this study to find the effects of ketamine compared to those of epidurally injected bupivacaine and fentanyl, and used this trial to study any potential side effects. Methods: In a double blind trial, 55 patients received either fentanyl, $0.3{\mu}g/kg/h$ (Group F), or fentanyl, $0.3{\mu}g/kg/h$, and ketamine, 0.1 mg/kg/h (Group FK), added to 0.125% bupivacaine, at rates as high as 2 ml/h, for patient controlled epidural analgesia (PCEA) following a transabdominal hysterectomy. Ten minutes before the operation, patients received 10 ml of 0.125% bupivacaine, with either 0.5 mg/kg ketamine or the same amount of normal saline with $50{\mu}g$ fentanyl added. The pain scores and the side effects were recorded at 1, 3, 6 and 24 hour post operation. Results: There were no differences in the pain scores or side effects between the two groups. Conclusions: We failed to find any effect of the addition of epidural ketamine compared to the that of the bupivacaine and fentanyl formula. However, it is suggested that further investigations will be required on the dose and route of administration.

• Science of Emotion and Sensibility
• /
• v.11 no.3
• /
• pp.427-439
• /
• 2008

In order to effectively communicate the fragrances of commercial perfumes to consumers, it is important to apply congruent colors to their bottles and packaging. This research investigated the cross-modal associations between colors and fragrances through two experiments. In the first experiment, bottle colors of more than 200 popular perfumes in the market were analyzed. Distinguishable color design patterns of the bottles were revealed in accordance with their fragrance types. The second experiment expanded the use of color-odor matching task to a test population of Korean participants. Participants selected colors evoked by fragrances of three test perfumes in a blind setting. These three perfumes had characteristic hues and their associated hues were similar with the real colors of their bottles. In addition, there were significant variations in color tone across fragrance notes, viz. the top notes, middle notes, and base notes. The results of the two experiments suggest the existence of robust cross-modal associations between particular colors and fragrances in commercial perfumery.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.41
• /
• pp.29.1-29.10
• /
• 2019

Background: Reduction in postoperative complications is of vital considerations in impacted third molar teeth surgery. The aim of this study was to compare postoperative complications of impacted third molar surgeries for bone removal using laser, piezoelectric equipment, and conventional rotary instruments. Methods: To address the research purpose, the investigator designed the prospective double-blind clinical trial study. The sample size was determined 20 (40 teeth) by sampling formula in any kind of operation. The data of patients were obtained in the different periods in terms of pain, trismus, swelling, ecchymosis, and patient's satisfaction and then analyzed using SPSS 20 software via paired t test and Wilcoxon and McNemar's tests. Results: The pain immediately after surgery and 2 days and 7 days after surgery was higher in the laser group. The swelling immediately after surgery was more in the laser group but not significant. The amount of mouth opening immediately after surgery and 2 days and 7 days after surgery was significantly lower in the laser group than in the piezosurgery group. The total duration of surgery and duration of osteotomy were significantly longer in the laser group. The patient's satisfaction from surgery with piezosurgery was more than that with laser, but this difference was not significant. Conclusion: Due to the rising demand for impacted wisdom tooth surgery, the present study suggests that hard tissue laser surgery and piezosurgery can clear the future of impacted molar surgery, and these approaches are more efficient in reducing postoperative complications compared to the conventional surgeries.

• Smart Structures and Systems
• /
• v.17 no.3
• /
• pp.471-489
• /
• 2016

Modal identification based on ambient vibration data has attracted extensive attention in the past few decades. Since the excitation for ambient vibration tests is mainly from the environmental effects such as wind and traffic loading and no artificial excitation is applied, the signal to noise (s/n) ratio of the data acquired plays an important role in mode identifiability. Under ambient vibration conditions, certain modes may not be identifiable due to a low s/n ratio. This paper presents a study on the mode identifiability of an instrumented cable-stayed bridge with the use of acceleration response data measured by a long-term structural health monitoring system. A recently developed fast Bayesian FFT method is utilized to perform output-only modal identification. In addition to identifying the most probable values (MPVs) of modal parameters, the associated posterior uncertainties can be obtained by this method. Likewise, the power spectral density of modal force can be identified, and thus it is possible to obtain the modal s/n ratio. This provides an efficient way to investigate the mode identifiability. Three groups of data are utilized in this study: the first one is 10 data sets including six collected under normal wind conditions and four collected during typhoons; the second one is three data sets with wind speeds of about 7.5 m/s; and the third one is some blind data. The first two groups of data are used to perform ambient modal identification and help to estimate a critical value of the s/n ratio above which the deficient mode is identifiable, while the third group of data is used to perform verification. A couple of fundamental modes are identified, including the ones in the vertical and transverse directions respectively and coupled in both directions. The uncertainty and s/n ratio of the deficient mode are investigated and discussed. A critical value of the modal s/n ratio is suggested to evaluate the mode identifiability of the deficient mode. The work presented in this paper could provide a base for the vibration-based condition assessment in future.

• Journal of Korean Clinical Health Science
• /
• v.3 no.3
• /
• pp.399-408
• /
• 2015

Objective. There were two objectives of the study, first was to identify the barriers as perceived by the patients and providers to access the low vision services and second was to identify the challenges faced by the main providers. Study design. Structured questionnaire based interviews of patients and providers Methodology. To find out the barriers to access of low vision services, the interviews based on structured questionnaire were conducted for two patient groups. The first group consisted of 97 visually impaired individuals attending the department of low vision services at Al-Shifa Trust Eye Hospital Rawalpindi while the second group included 56 visually impaired individuals attending the four rehabilitation centers/schools for the blind in Rawalpindi/Islamabad. To identify the barriers as perceived by the main providers of low vision services and challenges faced by them the interviews based on structured questionnaire were conducted for 19 low vision service providers. Results. From patients point of view, major barrier to low vision services identified was inability to visit hospital /rehabilitation center alone - 29.8% in hospital group and 33.9% in rehabilitation centers group, while the lack of social support, lack of family support, cost of travelling, long distance, afford ability, hesitation in using devices and lack of satisfaction were other important barriers identified. From providers' point of view, major barrier to uptake of services was the need for repeated follow-ups. Optometrists were the main provider of low vision services contributing to 47.4% of the providers. The major challenge faced by the providers was motivation of patients to use low vision devices. Conclusion. The major barrier to low vision services according to the patients is inability to visit the hospital alone, while according to providers, it is the need for repeated follow up which proves major barrier towards uptake of services. The motivation is the major challenge faced by providers, majority of which are optometrists.

• Journal of Periodontal and Implant Science
• /
• v.27 no.4
• /
• pp.701-722
• /
• 1997

It was reported that low dose doxycycline(LDD) regimen could inhibit pathologically elevated collagenase activity in the gingival crevicular fluid of petients with adult periodontitis without producing typical antibiotic side effects. The purpose of this study was to evaluate the effects of LDD regimen(20mg) administered during non-surgical therapy on clinical index and gingival crevicular fluid enzyme activity in diabetics who are at high risk for periodontal disease. Forty-nine subjects having at least two sites with probing pocket depths greater than 4mm were selected. In this double-blind, placebo-controlled study, the patients were administered 20 mg doxycycline capsule or placebo capsule b.i.d. for 2 weeks. Clinical parameters of dental plaque, gingival inflammation, probing pocket depth and probing attachment level were assessed at week 0, 2, 4, and 8. Gingival crevicular fluid samples were collected at the same time to evaluate the activities of collagenase and elastase. Clinical parameters and elastase activity were significantly reduced in all groups compared to the baseline value after treatment. Significantly greater reduction in pocket depth and gain in attachment level was shown in the LDD-administered group compared to placebo group in both adult periodontitis and diabetic patients. Total collagenase activity was also reduced significantly in all groups after treatment, but the greater reduction was seen in the LDD-administered diabetics group compared to relevant placebo group(at 4, 8week). Significantly greater reduction in active collagenase activity was also seen in the LDD-administered group compared to placebo group in diabetic patients(at 2, 4, 8week). These results indicated that use of low dose doxycycline could be aueseful adjunct to instrumentation therapy in the management of diabetic patient with periodontitis as well as adult periodontitis patient.

• ALGAE
• /
• v.31 no.2
• /
• pp.175-187
• /
• 2016

This study evaluated the effects of γ-aminobutyric acid (GABA)-enriched fermented sea tangle (GFST), as a functional food, on brain derived neurotrophic factor (BDNF)-related muscle growth and lipolysis, in a sarcopenic obesity high-risk group. Twenty-one middle-aged women (53-63 y) participated in this randomized, double-blind, placebo controlled study. Participants ingested either 1,000 mg of GFST (n = 10) or a sucrose placebo (CON) (n = 11) everyday, for 8 weeks. Subjects were asked to abstain from any regular exercise. Fasting venous blood samples, body composition and muscular strength were measured before and after supplementation period. Collectively, we demonstrated that GFST significantly decreased total fat mass and triglyceride in body composition, as well as significantly increasing serum BDNF (p < 0.001), angiotensin converting enzyme (p < 0.001), human growth hormone and insulin-like growth factor-1 levels (p < 0.05 and p < 0.05, respectively) accompanied by increased total lean mass (p < 0.01). Furthermore, the reported improvements in total work, knee extension and flexion at 60° s⁻¹ (p < 0.05), and peak torque normalized to body weight of knee flexion at 60° s⁻¹ (p < 0.05), support an ergogenic effect of GABA associated with increased growth factor levels. The use of GFST, as a functional food ingredient, to elicit anti-obesity effects and stimulate the release of muscle-related growth factors with increasing serum BDNF levels may provide a protective intervention for age-related degeneration such as sarcopenic obesity.

• The Journal of Korean Medicine
• /
• v.23 no.2
• /
• pp.180-189
• /
• 2002

Background and Purpose : The hemiplegic upper extremity is affected in many stroke patients, and recovery is often poor. The purpose of this study was to assess the efficacy of electroacupuncture (EA) in enhancing the upper extremity motor and functional recovery of ischemic stroke patients. Subjects and Methods : Forty ischemic stroke patients (the upper extremity Fugl-Meyer motor scale (FM) score lower than 46, lesion location within middle cerebral artery territory) within 2 weeks of stroke onset were randomly allocated to either an EA group that received EA treatment or a control group that received only routine ward care. The EA was applied at Quchi-Shousanli (LI11-LI10), Waiguan-Hegu (TE5-LI4) points on the hemiparetic side six times per week for 4 weeks. The frequency of stimulation was 25-50Hz and the intensity was set at a level sufficient to induce muscle contraction. EA treatment was given for 30 minutes and all patients of both groups received standard rehabilitation program. Outcomes were assessed, in a blind manner, before treatment began and at 4 weeks after treatment, with the FM, the Motor Power score (MP) for shoulder/elbow, and the subsection of the Modified Barthel Index (MBI) for drinking/feeding/dressing upper body/grooming. Results : These 2 groups had comparable clinical characteristics, lesion location, lesion size, and pretreatment impairment scores. By the end of treatment, the EA group showed significantly more improvement than the control group in the subsection of the FM for shoulder/elbow/coordination (6.4 vs. 3.7; P=0.047) and the MP for shoulder/elbow (5.3 vs. 3.3; P=0.008). The subsection scores of the MBI for drinking/feeding/dressing upper body/grooming were not significantly different between two groups. No adverse effects due to treatment were found Conclusion : These results suggest that EA enhances the upper extremity motor recovery of acute stroke patients. However, this study failed to demonstrate any significant functional benefit related with upper extremity. Future study should be carried out in a larger sample size and use the functional outcome measure that is more specific and sensitive to the upper extremity.

• Journal of Chest Surgery
• /
• v.53 no.1
• /
• pp.28-33
• /
• 2020

Background: When an arteriovenous fistula (AVF) is created using the basilic or deep cephalic vein, it is additionally necessary to transfer the vessels to a position where needling is easy; however, many patients develop wound-related postsurgical complications due to the long surgical wounds resulting from conventional superficialization of a deep AVF or basilic vein transposition. Thus, to address this problem, we performed videoscopic surgery with small surgical incisions. Methods: Data from 16 patients who underwent additional videoscopic radiocephalic superficialization, brachiocephalic superficialization, and brachiobasilic transposition after AVF formation at our institution in 2018 were retrospectively reviewed. Results: Needling was successful in all patients. No wound-related complications occurred. The mean vessel size and blood flow of the AVF just before the first needling were 0.73±0.16 mm and 1,516.25±791.26 mL/min, respectively. The mean vessel depth after surgery was 0.26±0.10 cm. Percutaneous angioplasty was additionally performed in 25% of the patients. Primary patency was observed in 100% of patients during the follow-up period (262.44±73.49 days). Conclusion: Videoscopic surgery for AVF dramatically reduced the incidence of postoperative complications without interrupting patency; moreover, such procedures may increase the use of native vessels for vascular access. In addition, dissection using a videoscope compared to blind dissection using only a skip incision dramatically increased the success rate of displacement by reducing damage to the dissected vessels.