• Imaging Science in Dentistry
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• v.54 no.3
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• pp.240-250
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• 2024

Purpose: This study was performed to assess the clinical validity and accuracy of a deep learning-based automatic landmarking algorithm for cone-beam computed tomography (CBCT). Three-dimensional (3D) CBCT head measurements obtained through manual and automatic landmarking were compared. Materials and Methods: A total of 80 CBCT scans were divided into 3 groups: non-surgical (39 cases); surgical without hardware, namely surgical plates and mini-screws (9 cases); and surgical with hardware (32 cases). Each CBCT scan was analyzed to obtain 53 measurements, comprising 27 lengths, 21 angles, and 5 ratios, which were determined based on 65 landmarks identified using either a manual or a 3D automatic landmark detection method. Results: In comparing measurement values derived from manual and artificial intelligence landmarking, 6 items displayed significant differences: R U6CP-L U6CP, R L3CP-L L3CP, S-N, Or_R-R U3CP, L1L to Me-GoL, and GoR-Gn/S-N (P<0.05). Of the 3 groups, the surgical scans without hardware exhibited the lowest error, reflecting the smallest difference in measurements between human- and artificial intelligence-based landmarking. The time required to identify 65 landmarks was approximately 40-60 minutes per CBCT volume when done manually, compared to 10.9 seconds for the artificial intelligence method (PC specifications: GeForce 2080Ti, 64GB RAM, and an Intel i7 CPU at 3.6 GHz). Conclusion: Measurements obtained with a deep learning-based CBCT automatic landmarking algorithm were similar in accuracy to values derived from manually determined points. By decreasing the time required to calculate these measurements, the efficiency of diagnosis and treatment may be improved.

• Journal of radiological science and technology
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• v.34 no.2
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• pp.105-116
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• 2011

In this study, we present the measurements of effective dose from CT of head & neck region. A series of dose measurements in anthropomorphic Rando phantom was conducted using a radio photoluminescent glass rod dosimeter to evaluate effective doses of organs of head and neck region from the patient. The experiments were performed with respect to four anatomic regions of head & neck: optic nerve, pons, cerebellum, and thyroid gland. The head & neck CT protocol was used in the single scan (Brain, 3D Facial, Temporal, Brain Angiography and 3D Cervical Spine) and the multiple scan (Brain+Brain Angiography, Brain+3D Facial, Brain+Temporal, Brain+3D Cervical spine, Brain+3D Facial+Temporal, Brain+3D Cervical Spine+Brain Angiography). The largest effective dose was measured at optic nerve in Brain CT and Brain Angiography. The largest effective dose was delivered to the thyroid grand in 3D faical CT and 3D cervical spine, and to the pons in Temporal CT. In multiple scans, the higher effective dose was measured in the thyroid grand in Brain+3D Facial, Brain+3D Cervical Spine, Brain+3D Facial+Temporal and Brain+3D Cervical Spine+Brain Angiography. In addition, the largest effective dose was delivered to the cerebellum in Brain CT+Brain Angiography CT and higher effective dose was delivered to the pons in Brain+Temporal CT. The results indicate that in multiple scan of Brain+3D Cervical Spine+Brain Angiography, effective dose was 2.52 mSv. This is significantly higher dose than the limitation of annual effective dose of 1 mSv. The effective dose to the optic nerve was 0.31 mSv in Brain CT, which shows a possibility of surpassing the limitation of 1 mSv by furthre examination. Therefore, special efforts should be made in clinical practice to reduce dose to the patients.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.6
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• pp.989-999
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• 2017

In this study, hydraulic experimental studies were conducted to estimate the empirical formulas of loss coefficient, which is necessary to calculate the energy loss occurred in the dividing channel junction of sewer system. The experimental apparatus was consisted of two outflow conduit with a $90^{\circ}$ angle to the inlet conduit, and the pressure and velocity heads are measured to analyze the energy losses in the branch. The measurements of the hydraulic grade line show that the hydraulic grade line was steeply descended at the dividing point due to the head loss, and the decreasing amount of velocity head increased with the increase of flowrate ratio. The head loss exponentially increased in the outlet with larger runoff as the increase of flowrate ratio and Froude number, and the head loss coefficient also increased. On the other hands, the head loss coefficients decreased in the outlet with smaller runoff as the increase of the flowrate ratio and Froude number. Using the experimental results, the empirical formulas of loss coefficient was suggested for each outlet, and the error of empirical formula was 3.91 and 5.19%, respectively. Furthermore, the total head loss coefficient calculated by the two empirical formulas was compared with the experimental results, and the error was 3.62%.

• Journal of the Korea Society of Computer and Information
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• v.18 no.9
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• pp.71-78
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• 2013

In this paper, the golf club head hit the golf ball moves at a constant velocity, then move in the same direction at a constant velocity of the golf club head, the velocity of the golf ball was hitting and flying the golf ball is calculated. If velocity is different before you hit the golf ball, each of the velocity of the golf ball is calculated. The purpose of this paper is to make it easy to find out the velocity of a club's head, the mass of a golf ball, the velocity or the direction of a golf ball after impact in playing golf. The results of the experiment are represented in tables and figures. And we also propose the comparison analysis between our research and other traditional ones, the implications, and futhur studies in the future. The results of this study, unlike other studies, it was can be seen that measurements of several factors superior to the measurement of the velocity of the golf ball.

• Journal of Nutrition and Health
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• v.39 no.3
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• pp.264-273
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• 2006

Elevated maternal plasma homocysteine concentrations have been associated with adverse pregnancy outcomes. Serum homocysteine levels may be affected by the MTHFR genotypes and the nutritional status of B vitamins including vitamin $B_2,\;B_6$, folate and vitamin $B_{12}$. We investigated whether postnatal growth measurements were influenced by maternal MTHFR genotypes and their mid-pregnancy serum vitamin B and homocysteine levels. In 130 pregnant women of 24-28 wks of gestation, the MTHFR genotypes, serum B vitamins and homocysteine concentrations were analyzed. Physical growth status was assessed in their offsprings by measuring height, weight, and head and chest circumferences from birth up to 24 months. Serum homocysteine levels were higher in the subjects with T/T genotype than those with the C/T or C/C. Heights and head and chest circumferences of offsprings from the T/T mothers were significantly lower than those from the C/C or C/T mothers only when the serum homocysteine levels were above the median. The mean height of offsprings from the T/T mothers was significantly lower than those from the C/C and C/T mothers. The mean weight and head circumferences of offsprings born from the mothers whose mid-term pregnancy PLP levels were in the lowest quartile was significantly lower than those from mothers in the highest quartile. Heights and head circumferences of offsprings from the T/T mothers were significantly lower than those from the C/C or C/T mothers only when the serum FAD levels were in the lowest quartile. These results suggest that postnatal growth up to 24 months may be influenced by the maternal C677T MTHFR genotypes, and mid-pregnancy serum homocysteine and vitamin B status.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.23 no.1
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• pp.43-51
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• 2017

Background: This study was carried out to compare the effects of shoulder stabilization exercise and thoracic extension exercise including deep neck flexor exercise on posture and pain targeting physical therapists and occupational therapists with forward head posture. Methods: A total of 30 physical therapists and occupational therapists (15 males, 15 females), who are working in the nursing hospital at Daejeon, were randomly divided into a shoulder stabilization group (n=10), a thoracic extension exercise (n=10), and a control group (n=10), and 3 times were carried out for 8 weeks. Results: In the results of all measurements, 2 groups except for the control group showed a significant change in the recovery of forward head posture, and the should stabilization exercise group showed a relatively superior effect compared to the thoracic extension exercise group. Conclusions: These results of a study will be a basic data for the development of the forward head posture exercise therapy program.

• Journal of the Korean Society of Physical Medicine
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• v.1 no.1
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• pp.93-108
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• 2006

Purpose : To evaluate effects of McKenzie exercise on the functional recovery and forward head posture of chronic neck pain patients. Methods : The subjects were consisted of fifteen patients who had abnormal neck posture, mild neck pain (28 males, 17 females; mean aged 21.9) from 19 to 33 years of age(mean age 21.9). All subjects were received McKenzie exercise for 35 minutes with clinical massage per day three times a week during 4 weeks period. Neck disability index was used to measure functional disability level. Visual analogue scale(VAS) was used to measure subjective pain level. craniovetebral angle(CVA), cranial rotation angle(CRA) was used to measure forward head posture with digital camera. All measurements of each patients were measured at pre-treatment and after 2 week, after 4 week, post-treatment on 2 week. Result : The VAS of McKenzie exercise was significantly reduced between pre-treatment and post-treatment (p<.05) and effects of pain reduce was continued follow 2 weeks. The Neck Disability Index of McKenzie exercise was significantly reduced between pre-treatment and post-treatment (p<.05) and effects of pain reduce was continued follow 2 weeks. The CVA of McKenzie exercise was significantly reduced between pre-treatment and post-treatment (p<.05) and effects of pain reduce was continued follow 2 weeks. The CRA of McKenzie exercise was not significantly reduced between pre-treatment and post-treatment (p<.05). Conclusion : McKenzie exercise improved pain and function of Chronic neck pain patients.

• 한국해양학회지
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• v.13 no.2
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• pp.26-30
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• 1978

This work concerns morphological studies of Alaska pollak, Theragra chalcogramma(PALLAS), and of the Nogari which is generally known as an immature form of the Alaska pollack. Observations are made to see whether significant differences in the meristic and morphometric characters can be recognized between two groups. Four meristic characters, namely, first anal fin rays, first dorsal fin rays, gill rakers, vertebra and three morphometric characters, namely, head length, snout length, eye diameter are chosen for the study. Results of the analyses reveal that the differences in all the selected meristic characters between Nogari and Alaska pollack are found to be not significant. Differences in the snout length in relation to the head length are found to be not significant . However, the differences in the head length in relation to the body length and the differences in eye diameter in relation to the head length are both found to be significant. In spite of the lack of informations on genetypic variations, it is reasonable to state that the Nogari appears to be a juvenile form of the Alaska pollak, and the differences in certain morphometric measurements between two groups are likely to be associated with the differences in the relative growth rates during the life stages.

• Osong Public Health and Research Perspectives
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• v.9 no.6
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• pp.354-361
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• 2018

Objectives: The purpose of this study was to explore the effects of injection laryngoplasty (IL) with hyaluronic acid in patients with vocal fold paralysis (VFP). Methods: A total of 50 patients with VFP participated in this study. Pre- and post-IL assessments were performed, which included analyzing the sustained vowel /a/ phonation, and the patient reading 1 Korean sentence from the "Walk" passage that comprised 25 syllables in 10 words. To investigate the effect of IL on vocal fold function, acoustic analysis (acoustic voice quality index, cepstral peak prominence, maximum phonation time, speaking fundamental frequency) was conducted and auditory-perceptual (grade and overall severity), visual judgment (gap), and self-questionnaire (voice handicap index-10) assessments were performed. Results: The patients with VFP showed statistically significant differences between pre-and post-IL assessments for acoustic and auditory-perception, visual judgment, and self-questionnaire assessments. Conclusion: The patients with VFP showed positive change in vocal fold function between pre- and post-IL measurements. The findings showed that IL with hyaluronic acid is an effective method to improve vocal fold function in patients with VFP.

• Korean Journal of Otorhinolaryngology-Head and Neck Surgery
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• v.61 no.12
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• pp.663-668
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• 2018

Background and Objectives The main objectives of this study were to determine the clinical usefulness of the program-assisted and real ear measurement (REM)-assisted fitting of hearing aids. Subjects and Method Fifteen participants with moderate to moderately severe hearing loss were enrolled in this study. Objective and subjective fitting results were assessed to compare the benefits between the program-assisted fitting (using a software fitting program) and the REM-assisted fitting. Real ear insertion gain (REIG), sound-field audiometry using warble tone, and Korean Hearing in Noise Test (K-HINT) were performed as objective tests. Sound quality rating was performed as a subjective test. Results In the program fitting, 48.89% of fitting points failed to come within ${\pm}10dB$ of the REIG target. In the REM fitting, however, the percentage of failure significantly decreased to 23.33% (p=0.013). In K-HINT test, the reception threshold for speech in quiet situation significantly decreased from 50.1 dB HL with the program fitting to 44.7 dB HL after the REM fitting (p<0.001). In front noise condition, signal-to-noise ratio improved from 4.53 dB to 3.50 dB with the REM fitting without statistical significance (p=0.099). In the sound quality rating, the REM fitting ($4.27{\pm}0.56$) showed a significantly better sound quality ratings than the program fitting ($3.69{\pm}0.74$) (p=0.017). Conclusion The REM fitting showed better results in both subjective and objective measurements than the program fitting.