• Journal of the Korean Society for Nondestructive Testing
• /
• v.28 no.6
• /
• pp.519-523
• /
• 2008

Poisson's ratio is one of elastic constants of elastic solids. However, it has not attracted attention due to its narrow range and difficult measurement. Transverse wave velocity as well as longitudinal wave velocity should be measured for nondestructive measurement of Poisson's ratio. Hard couplant for transverse wave prevents transducer from scanning over specimen. In the present work, a novel measurement of Poisson's ratio distribution was proposed. Immersion method was employed for the scanning over the specimen. Echo signals of normal beam longitudinal wave were collected. Transverse wave modes generated by mode conversion were identified. From transit time of longitudinal and transverse waves, Poisson's ratio can be determined without information of specimen thickness. This technique was demonstrated for aluminum and steel specimens.

• The Transactions of the Korean Institute of Electrical Engineers B
• /
• v.53 no.1
• /
• pp.16-23
• /
• 2004

Permanent magnet-excited transverse flux linear motor(TFLM) is known to have more excellent ratio of force to weight than any other linear motors. But, thrust generated by phase current is non-linear with regard to current and relative position like switched reluctance motor. This makes current and speed controller design difficult. This paper presents a method on minimization of thrust ripple of permanent magnet-excited transverse flux linear motor. Using genetic algorithm(GA), optimal current waveform can be found under the constraint conditions such as current limit, minimum of ohmic loss and limited rate of change of current etc. The effectiveness is verified through computer simulation and experimental test results.

• Journal of Korea Water Resources Association
• /
• v.54 no.12
• /
• pp.1305-1316
• /
• 2021

In this study, a new empirical formula for 2D transverse dispersion coefficient was developed using the results of previous tracer test studies, and the performance of the formula was evaluated. Since many tracer test studies have been conducted under the conditions where the width-to-depth ratio is less than 50, the existing empirical formulas developed using these imbalanced tracer test results have limitations in applying to rivers with a width-to-depth ratio greater than 50. Therefore, in order to develop an empirical formula for transverse dispersion coefficient using the imbalanced tracer test data, the Synthetic Minority Oversampling TEchnique (SMOTE) was used to oversample new data representing the properties of the existing tracer test data. The hydraulic data and the transverse dispersion coefficients in conditions of width-to-depth ratio greater than 50 were oversampled using the SMOTE. The reliability of the oversampled data was evaluated using the ROC (Receiver Operating Characteristic) curve. The empirical formula of transverse dispersion coefficient was developed including the oversampled data, and the performance of the results were compared with the empirical formulas suggested in previous studies using R². From the comparison results, the value of R² was 0.81 for the range of W/H < 50 and 0.92 for 50 < W/H, which were improved accuracy compared to the previous studies.

• The korean journal of orthodontics
• /
• v.46 no.5
• /
• pp.331-342
• /
• 2016

Objective: To evaluate the accuracy and reliability of the diagnostic tools available for assessing maxillary transverse deficiencies. Methods: An electronic search of three databases was performed from their date of establishment to April 2015, with manual searching of reference lists of relevant articles. Articles were considered for inclusion if they reported the accuracy or reliability of a diagnostic method or evaluation technique for maxillary transverse dimensions in mixed or permanent dentitions. Risk of bias was assessed in the included articles, using the Quality Assessment of Diagnostic Accuracy Studies tool-2. Results: Nine articles were selected. The studies were heterogeneous, with moderate to low methodological quality, and all had a high risk of bias. Four suggested that the use of arch width prediction indices with dental cast measurements is unreliable for use in diagnosis. Frontal cephalograms derived from cone-beam computed tomography (CBCT) images were reportedly more reliable for assessing intermaxillary transverse discrepancies than posteroanterior cephalograms. Two studies proposed new three-dimensional transverse analyses with CBCT images that were reportedly reliable, but have not been validated for clinical sensitivity or specificity. No studies reported sensitivity, specificity, positive or negative predictive values or likelihood ratios, or ROC curves of the methods for the diagnosis of transverse deficiencies. Conclusions: Current evidence does not enable solid conclusions to be drawn, owing to a lack of reliable high quality diagnostic studies evaluating maxillary transverse deficiencies. CBCT images are reportedly more reliable for diagnosis, but further validation is required to confirm CBCT's accuracy and diagnostic superiority.

• Advances in aircraft and spacecraft science
• /
• v.10 no.3
• /
• pp.281-302
• /
• 2023

In this paper, bending analysis of exponentially varying functionally graded (FG) plate is presented using trigonometric shear deformation theory (TSDT) considering both transverse shear and normal deformation effects. The in-plane displacement field consists of sinusoidal functions in thickness direction to include transverse shear strains and transverse displacement include the effect of transverse normal strain using the cosine function in thickness coordinate. The governing equations and boundary conditions of the theory are derived using the virtual work principle. System of governing equations, for simply supported conditions, Navier's solution technique is used to obtain results. Plate material properties vary across thickness direction according to exponential distribution law. In the current theory, transverse shear stresses are distributed accurately through the plate thickness, hence obviates the need for a shear correction factor. TSDT results are compared with those from other theories to ensure the accuracy and effectiveness of the present theory. The current theory is in excellent agreement with the semi-analytical theory.

• Journal of the Korea Convergence Society
• /
• v.9 no.3
• /
• pp.137-144
• /
• 2018

The purpose of this study was to investigate the fusion effects and difference them of the deep transverse stroking, manual stretching exercise and active muscle release technique on psoas major muscle thickness and muscle tone, and pelvic angle in non-specific low back pain patients. Psoas major muscle thickness was significantly decreased after the application of the deep transverse stroking $0.19{\pm}0.16cm$ (p <0.05), manual stretching exercise $0.18{\pm}0.14cm$ (p <0.05), and active muscle release technique $0.43{\pm}0.35cm$ (p <0.05). The pelvic angle was significantly decreased after the application of the deep transverse stroking $4.48{\pm}1.63^{\circ}$ (p <0.05), manual stretching exercise $5.36{\pm}2.04^{\circ}$ (p <0.05), and active muscle release technique $7.24{\pm}2.23^{\circ}$ (p <0.05). The Psoas major muscle tone was significantly decreased after application of the deep transverse stroking $0.96{\pm}0.93Hz$ (p <0.05), but manual stretching exercise $0.87{\pm}1.20Hz$ (p> 0.05) and active muscle release technique $0.82{\pm}0.98Hz$ (p> 0.05) there was no significant difference after application. There were no significant differences between the three intervention methods in the pelvic angle and psoas major muscle thickness and tone changes. In order to change psoas major muscle thickness and pelvic angle, three intervention methods should be applied appropriately according to the condition and environment of the patient, and deep transverse stroking is more effective for changing psoas major muscle tone.

• Proceedings of the KOSOMBE Conference
• /
• v.1989 no.05
• /
• pp.23-26
• /
• 1989

This paper describes the automatic recognition technique for heart enlargement diagnosis with the chest X-ray films enhanced by digital image processing. The technique measures a maximum transverse of the daiphragm and a maximum transverse of the heart by means of direction signature algorithms, then calculates the desired ratio of these two measured values. This is often refered to a cadiothoracic ratio which gives as useful clue for heart enlargement symptom. The experiment results in this paper show presented method is more efficient than the manual diagnosis method of the symptom.

• Korean Journal of Veterinary Research
• /
• v.23 no.1
• /
• pp.119-122
• /
• 1983

Paravertebral anesthesia for operation of abdominal wall in Korean cattle were effectively accomplished with the following technique. Any problems in surgical procedure were not observed under the block of ventral branches of the last thoracic nerve and the first and second lumbar nerves with the administration of preanesthetic. The site of injection for blocking of ventral branches of the thirteenth thoracic nerve were approximately 5cm lateral to the midline from the posterior edge of spinous process of the 13th thoracic vertebra and about 10ml of local anesthetic was injected immediately anterior to the transverse process of the first lumbar vertebra through thin site. The block of ventral branches of the first and second lumbar nerves were obtained by injecting 10ml of local anesthetic immediately below the posterior edge of transverse process of the 2nd and 4th lumbar vertebra, respectively.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.28 no.1
• /
• pp.40-45
• /
• 2008

Immersion ultrasonic testing (UT) was used to determine elastic moduli of solid materials instead of the widely-used contact UT method. Conventionally, immersion UT is only used for determining the longitudinal wave speed. However, in this research, transverse wave speed was measured through finding transverse wave echoes caused by mode-conversion at material's boundary. Also, even in the cases when wave speeds could not be determined due to unknown thickness, Poisson's ratio was able to be calculated from the ratio of longitudinal and transverse wave speeds. This technique was verified for several materials, and it was found that higher accuracy was obtained by immersion UT method for materials either with relatively high wave speed or with relatively small Poisson's ratio. This technique thus will be suitable fur ceramics or high strength materials.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.29 no.3
• /
• pp.145-152
• /
• 1987

This paper suggests a method for the analysis of box girders which are subject to the membrane and the plate bending actions, Moreover, the method is applied to the box girders under distributed loads which have various geometrical types of cross sections and are made out of different materials. The approach is based on the finite element technique in which the structure is considered to be a spatial assemblage of flat plate elements and the deformations of the plates are to be approximated with 9-noded parabolic isoparametric elements. The results are summarized as follows. 1.In all models, the larger the widths of top flange inside of web are, the larger the vertical deflections are. 2.The maximum transverse and longitudinal moments in the composite box girders are judged to be larger than those in the RC box girders. 3.The transverse and the longitudinal moments in top flange of composite box. girders are larger than those in that of the RC box girders. 4.The transverse and longitudinal moments in web and bottom flange of the composite box girders are estimated to be very small in compare to those in web and bottom flange of the RC box girders.