• Design & Manufacturing
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• v.16 no.2
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• pp.39-45
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• 2022

Sheet Metal Forming by Press Forming Process takes a lot of time and cost from mold design to manufacturing. Therefore, all of die-makers are continuously conducting research to reduce the number of mold processes or the size of blanks to reduce costs. In the case of Forming complex shapes such as automobile component, wrinkles and cracks occur, so draw beads are used. Draw beads play an important role in suppressing the inflow of materials and minimizing the size of blanks. Factors that affect material flow include draw bead, blank holding pressure, lubricant, and surface roughness of punch and die. Most of the factors affect friction. In this study, after classifying circular beads and rectangular beads in cylindrical drawing molds using the AutoForm analysis program, the factors affecting the material inflow were considered.

• PNF and Movement
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• v.15 no.3
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• pp.217-226
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• 2017

Purpose: The purpose of this study was to determine the effects of a modified abdominal draw-in maneuver on trunk stability and functional capacity as well as pain in patients with chronic low back pain. Methods: The study included 3 patients with chronic low back pain who volunteered to participate. The modified abdominal draw-in maneuver included a posterior pelvic tilt, a traditional abdominal draw-in maneuver, and a vibration sensory feedback device. Voluntary abdominal contraction using the vibration sensory feedback device was performed by the subjects for more than 1 hour per day, 5 times per week, for 6 weeks along with common low back pain treatment. Electromyographic signals in the rectus abdominis (RA), external oblique (EO), internal oblique (IO), and erector spinae (ES) muscles were measured to compare muscle activation. The degree of pain was measured using the visual analogue scale (VAS), and functional capacity was measured using the Korea Oswestry Disability Index (K-ODI). All results were compared to the means before and after intervention. Results: After the intervention, the RA, EO, and IO showed increased muscle activation and the ES showed decreased muscle activation. The visual analogue scale decreased after intervention and the K-ODI decreased after intervention. Conclusion: Modified abdominal draw-in maneuvers in daily life combined with therapeutic exercises may be effective in relieving pain and dysfunctions in chronic low back pain patients.

• Journal of computational fluids engineering
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• v.18 no.4
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• pp.69-73
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• 2013

Mass manufacturing of optical fiber includes the process of very thin glass fiber drawing by heating and softening the high purity silica preform and applying the draw tension on the softened tip of preform neck-down profile in a draw furnace. In this computational study, this process is numerically modeled with simplified geometry of the draw furnace which is comprised of essential parts such as concentric graphite heater, muffle tube, and insulation surrounding the heater. The iterative computational scheme is employed between one-dimensional model of neck-down profile prediction and two-dimensional axisymmetric thermo-fluid CFD computation of radiative heating and working gas convection. The computational results show the experimentally observed neck-down profile in heated section of preform, while yielding the reasonable values of draw tension and heater wattage. Also, this study analyzes and discusses the effects of heating conditions such as heater length and temperature on several important aspects of glass fiber drawing process.

• Textile Coloration and Finishing
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• v.22 no.3
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• pp.272-281
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• 2010

This paper surveys the effects of drawing conditions of the worsted staple yarns on the mechanical properties of the knitted fabrics for highly aesthetical fabrics. The drawn worsted yarns were made on the yarn drawing system with various draw ratios under the fixed conditions of setting time, reduction and oxidation. The knitted fabric specimens were prepared on the 16 gauge circular knitting machine using these drawn worsted staple yarns. The tensile, shear, bending, compression and surface properties of these knitted fabrics were measured by KES-FB-AUTO-A system and also discussed with the drawing conditions. The tensile linearity, shear stiffness and bending rigidity decreased with increasing draw ratio. Any changes were not shown on the compressional properties with drawing conditions. But the friction coefficient of the knitted fabric on the course direction increased with increasing draw ratio, while there was no change according to the draw ratio on the wale direction.

• Journal of the Semiconductor & Display Technology
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• v.18 no.2
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• pp.23-28
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• 2019

Wire breakage in drawing, which is the most critical process in glass fiber manufacturing, is caused by numerous factors such as height, drawing speed, and air flow. The vibrations of the draw tower, however, is the most dominant factor to create the wire breakage. In this study, the structure of a draw tower has been analyzed through experiments and computer simulations to figure out the main reasons of the vibrations. And the design alterations were applied to the machine to identify the effects of those alterations. The result shows that design alterations of the draw tower structure can suppress the 87% of the vibrations, and further can prevent the wire breakage.

• Journal of the Korean Society of Physical Medicine
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• v.17 no.1
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• pp.117-125
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• 2022

PURPOSE: This study was carried out to examine the changes in the trunk control ability and hand grip when the abdominal draw-in maneuver using breathing was applied to stroke patients, and provide basic data regarding the trunk stabilization exercise. METHOD: After randomly placing patients in group I-applying the existing abdominal draw-in exercise and group II -applying the abdominal draw-in exercise using breathing, the intervention program was performed ten times per set (five sets per session), once a day, four times a week, for a total of four weeks. For the pre-tests before the intervention, trunk damage and hand grip were measured. After the four weeks of intervention, post-tests were conducted in the same way as the pre-tests for analyzing the study results. RESULTS: Both groups had significant differences in trunk control ability and hand grip (p < .05). The comparison between the two groups showed, significant differences only in the trunk control a ability(p < .05). CONCLUSION: The abdominal draw-in exercise using breathing led to the efficient contraction of abdominal muscles, which implies this is a more effective intervention to improve the trunk control ability.

• Membrane Journal
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• v.28 no.3
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• pp.157-168
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• 2018

Potassium tannate (TA-K), which is prepared by base treatment of the bio-renewable tannic acid (TA), was evaluated for its potential application as a draw solute for water purification by forward osmosis. The forward osmosis and recovery properties of TA-K were systematically investigated. In the application of forward osmosis through the active layer facing feed solution (AL-FS) method, the water flux of TA-K draw solution was significantly higher than that of the TA draw solution, while that of the latter was not identified. At a low concentration of 100 mM, the osmotic pressure (1,135 mOsmol/kg) of the TA-K draw solution was approximately 6.5 times that (173 mOsmol/kg) of the NaCl draw solution. Furthermore, the water flux and specific salt flux (6.14 LMH, 1.26 g/L) of the TA-K draw solution at 100 mM were approximately 2.5 and 0.5 times those of the NaCl draw solution (2.46 LMH, 2.63 g/L) at the same concentration, respectively. For reuse, TA-K was precipitated by using a metal ion and recovered through membrane filtration. This study demonstrates the applicability of a phytochemical material as a draw solute for forward osmosis.

• Membrane Journal
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• v.29 no.2
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• pp.111-121
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• 2019

An organic citrate series draw solute was synthesized using diethyl malonate for forward osmosis. The structure of the final compound potassium pentane-1,3,3,5-tetracarboxylate was confirmed by $^1H-NMR$ and $^{13}C-NMR$ analysis. Osmotic pressure, solubility, water permeability and reverse salt flux were measured for the properties of the draw solute. Forward osmosis results showed that the draw solute exhibited higher water flux than other draw solutes of trisodium citrate and tripotassium citrate. Reverse salt flux of all the organic daw solutes was much lower than that of NaCl. The osmotic pressure of the synthesized draw solute was 25% lower than that of NaCl. The solubility of the draw solute was 317 g/ 100 g water, which is 8.8 times higher than that of NaCl. A commercialized nanofiltration membrane was used for the recovery of the draw solute. The draw solute could be effectively recovered at low pressure.

• Textile Coloration and Finishing
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• v.3 no.1
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• pp.8-16
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• 1991

In order to investigate the fine structure of PET films, PET films were stretchd at various draw ratios (2, 3, 4, 5) below $T_g$ ($72^{\circ}C$) and then annealed at various temperatures (125, 150, 175, $200^{\circ}C$) under free-annealed (FA) and taut-annealed (TA) conditions. Such changes as thermal shrinkage, crystallinity, crystallite size, dynamic viscoelasticity and thermal behaviour were measured in relation to the draw ratio and annealing condition.The following results were obtained. 1. Thermal shirinkage increased with increasing annealing temperature and draw ratio, but decreased in case of draw ratio 4 (draw ratio 3 at $200^{\circ}C$) and above it. 2. The degree of crystallinity of FA samples were higher than those of TA samples. 3. Tan 5 of TA samples were less than those of FA samples, and storage moduli (E') and loss moduli (E") of FA samples were less than those of TA samples; moreover, maximum tan '||'&'||' temperature of FA samples were shifted toward higher temperature than those of TA samples. 4. The melting endotherm ($T_m$) and heat of fusion $(\DeltaH)$ of the PET film increased with the draw ratio and annealing temperature; in addition, premelting endotherm ($T_m$) and heat of fusion $(\DeltaH)$ of the local crystallization in the FA samples were larger than those of TA samples. 5. The X-ray diffraction pattern displayed sharp peaks gradually with the draw ratio and annealing temperature. 6. Crystallite sizes of FA samples were larger than those of TA samples.

• Journal of The Korean Society of Integrative Medicine
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• v.12 no.2
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• pp.177-186
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• 2024

Purpose : The purpose of this study was to use oral instruction and taping to induce abdominal draw-in in the previous study, but there is a lack of research on the comparison of effects. Therefore, in this study, we would like to study how the effect of oral instruction, taping, and no feedback can affect muscle activity when performing abdominal draw-in pier exercises. Methods : Before the experiment, group A trained piers and applied only draw-in piers, group B applied taping feedback, and group C were divided into three groups per week for six weeks, and three sets of contractions for five seconds per group were performed five times, and a minute break was provided between each exercise. As a measurement tool, a wireless surface electromyography (EMG) was used to measure surface electromyography (Telemyo-DTS, NORAXON, USA) that derives a synthetic unit of muscle using a surface electrode. For statistical processing of data, the analysis is performed using the SPSS/PC Version 25.0 statistical program for Windows, and the statistical significance level is a=.05 Results : First, the duration was somewhat shorter in order to more accurately compare the muscle activity of the core muscles. Therefore, future research needs to be research that can be exercises with precise biofeedback and taping applied over a longer period of time. Secondly, it is believed that there is no significant difference, since the subjects were studied in healthy young adult men and women, not patients. Thirdly, they could not control the daily life of the subjects. Through future research, it is necessary to analyze the correlation between muscle activity and abdominal muscle thickness by adding ultrasound in addition to muscle activity in various age groups. Conclusion : During draw-in bridge exercise according to feedback, the muscle activity of the back muscle increased, and there was no significant difference in the muscle activity of the back muscle according to each feedback. Therefore, both the feedback applied during the draw-in pier exercise and the control group are effective in changing the thickness of the abdominal muscles.