• Journal of international Conference on Electrical Machines and Systems
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• v.2 no.3
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• pp.295-299
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• 2013

This paper presents the new structure of a spindle motor for hard disk drive (HDD). It can produce axial force as well as torque without a pulling plate or a pulling magnet required for the normal operation of a hydrodynamic bearing in rotating-shaft structure. The proposed models have different air gap length along the axial direction by changing the thickness of permanent magnet (PM). One has a single slope and the other has double slopes on the surface of PM. For the design of the proposed models, variables are defined and its effects on the motor performances are investigated by 3-demensional finite element analysis (FEA). The equi-performance curves are investigated for the main characteristics of the spindle motor such as generated torque, axial force and torque ripple ratio. The validity of the proposed models is verified by the feasibility study and performance evaluation.

• Journal of Animal Environmental Science
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• v.8 no.2
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• pp.99-106
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• 2002

This study was conducted to improve utilization efficiency of slurry and choose a suitable type of tractor power which can be attached by manure spreader in the paddy field. In the paddy field, the pulling force for the spreader was measured by using a measurement system installed between tractors with and without the spreader. The soil moisture contents at the 0${\sim}$10cm and 10${\sim}$20cm depth of test soil(SiCL) were 28.45% d.b. and 23.47% d.b., respectively in average while Cone Index at l0cm and 15cm depth were 14.5kPa and 16.2kPa, respectively. It was impossible to measure the soil moisture contents and Cone Index below 20cm depth of the soil because the hardness of the soil increased greatly. Thereafter, hard pan of the sampled soil was found at 15${\sim}$20cm depth. While the required power only for the dragged tractor was found to be 3.44kW in the test field, the required pulling powers of tractor considering the pumping were 8.48${\sim}$12.48kW, 12.19${\sim}$16.19kW, 16.96${\sim}$20.96kW, respectively for 2 tons, 3 tons, and 4 tons of tank capacity. As the tank capacity increased, the sinkage of soil were also increased to 7cm, l0cm, and 12cm, respectively for the tractors with 2 tons, 3 tons and 4 tons of tank capacity. Considering about 60% of pulling efficiency of tractor, a tractor which had lower than 25.74kW of pulling power was suitable to pull the spreader and spread the slurry simultaneously for manure spreader with 2 tons of tank capacity. 29.42kW${\sim}$36.78kW of pulling power was found to be optimum for the tractor with 3 tons of tank capacity while over 40.45kW for 4 tons of tank capacity.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.5
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• pp.345-349
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• 2000

$Al_2O_3/ZrO_2$eutectic fibers were grown by micro-pulling down technique and investigated their microstructure as a function of solidification rate. $Al_2O_3/ZrO_2$eutectic fibers 0.2~2 mm in diameter and 500 mm in length have been grown with a pulling rate of 0.1~15 mm/min. The eutectic microstructures changed as a function of fulling rate from rod-shaped to cellular shape containing some thin lamellar pattern via uniform lamellar structure. Typical lamellar thickness decreased from about 380 nm to 110 nm as the pulling rate increased from 1 mm/min to 15 mm/min. The interlamellar spacing fitted with the inverse-square-root dependence on pulling rate according to $\lambda$= $1{\times}v^{-1/2}$, where $\lambda$ has the dimension in $\mu\textrm{m}$ and v is $\mu\textrm{m}$/s. Hardness value reached 13.1 GPa at 15 mm/min of pulling rate and tensile strength 900 MPa at 10 mm/min were also increased as the interlamellar spacing decreased.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.10a
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• pp.327-328
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• 2009

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.109-110
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• 2011

• Journal of Korean Foot and Ankle Society
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• v.6 no.1
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• pp.86-91
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• 2002

Purpose: This study was designed to evaluate whether the method "Distal pulling with wire" after primary repair of Achilles tendon, can result in early restoration of ankle motion. Materials and Methods: In 14 cases of tendocalcaneus repair, the proximal stump was pulled down distally by wire and fixed the ends of wire to the transcalcaneal K - wire. We evaluated the range of motion of ankle joint at 4th, 6th, 12th week in 10 patients whom we followed up for more than 1 year. We evaluated the results of Achilles tendon repair by Hooker's criteria. Results: Range of motion of ankle joint revealed as follows. Degree of mean dorsiflexion improved - $5.1^{\circ},\;15.0^{\circ},\;22.4^{\circ}$ at 4th, 6th and 12th week respectively, while plantarflexion improved $21.5^{\circ},\;32.7^{\circ}$ and $42.3^{\circ}$ respectively. At one year follow up, seven of them had no problems in active daily life and sports activities. According to Hooker's criteria, the result rated excellent in nine, satisfactory in one. Conclusion: Early gain of ankle joint motion was possible by "Distal pulling with wire" after primary repair of Achilles tendon.

• Physical Therapy Korea
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• v.19 no.4
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• pp.32-37
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• 2012

The purpose of this study was to investigate the quantitative data of downward pulling tension in subjects with scapular downward rotation syndrome (SDRS) before and after 6-week self scapular upward rotation exercise (SURE) program. Eleven subjects with bilateral SDRS. The downward pulling tension(DPT) was measured digital tension-meter. The tension force data were collected using a surface electromyography before and after a 6-week self-scapular SURE program. The significance of difference between pre- and post-program was assessed using a paired t-test, with the level of significance set at ${\alpha}$=.05. The results showed that significant differences between pre- and post-SURE program were found for DPT (p<.05). These findings suggest that 6-week self SURE program is effective for reducing DPT in subjects with SDRS. Additionally, our DPT measurement can be useful for maintaining shoulder position and providing quantitative data between pre- and post-SURE program during passive correction of scapular position test.

• Journal of Korean society of Dental Hygiene
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• v.20 no.6
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• pp.973-980
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• 2020

Objectives: This study was to analyz the effects of comparative evaluation of the effects of oil pulling on periodontal indices. Methods: A total subjects were 38; control group (19 subjects) and experimental group (19 subjects). In the experimental group, coconut oil was provided and rinsed the mouth for about 10 minutes once a day. We evaluated possession rate of pocket depth (≥4 mm), possession rate of bleeding on exploring and possession rate of gingival recession (≥1 mm). Results: The possession rate of pocket depth (≥4 mm), bleeding on exploring and gingival recession (≥1 mm) significant difference in interaction between the group and measurement time. Conclusions: The findings of this study indicate that dental hygiene process and oil pulling specialists in care of periodontal diseases were effective mediation.

• Safety and Health at Work
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• v.7 no.3
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• pp.237-243
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• 2016

Background: This study examined the relationship between interhandle distances and upper limb exertion during simply pushing and pulling of a cart with four swivel wheels, defined by a roll box pallet (RBP) in a Japanese industrial standard. Methods: Six healthy young male participants were asked to push and pull an RBP at a distance of 5.2 m under six conditions corresponding to different interhandle distances (40 cm, 60 cm, and 80 cm) and weights (130 kg and 250 kg). The upper limb exertion was studied by shoulder abduction and flexion, and elbow flexion, as well as surface electromyogram (EMG) in shoulder extensor, and elbow flexor and extensor. Participants were required to provide subjective evaluations on operability after each trial. Results: Subjective operability indicated that a narrower interhandle distance had a better operability for pushing. Interhandle distance was also related to upper limb exertion especially for pushing. A narrow interhandle distance caused smaller shoulder adduction but larger elbow flexion. The normalized EMG data revealed that muscular activity became smaller with a narrow interhandle distance in shoulder extensor. During the pulling task, elbow flexion was smaller at a narrow interhandle distance, although subjective operability and normalized EMG were not significantly varied. Conclusion: A wider interhandle distance, such as 80 cm, was not suitable in the forwardbackward movement of the RBP. Therefore, this study concluded that an interhandle distance of 40 cm would be suitable for pushing and pulling an RBP to protect the workers' hands against the risk of injury by installing inner handles.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1211-1214
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• 2004

High-heeled women have been identified with balance control problems. The purposes of this study were to objectively quantify the displacements and velocities of center-of-pressure (COP) of body during waist pulling and to compare the differences between barefooted and high-heeled situations. We used a waist pulling system which has three different magnitudes to sway the subjects. We found that the kinematic information of barefooted and high-heeled women's COP is very important in understanding the mechanism of postural balance control of women in every-day life. In the high-heeled's case, the displacement of COP increases in 200％ as against bare footed. Also the velocity variation of COP grows three times than the bare footed. COP analysis in postural balance study of high-heeled women is also considered useful in development of the safety systems that prevent high-heeled women from falling