• Proceedings of the KWS Conference
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• 1994.10a
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• pp.115-118
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• 1994

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.3B
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• pp.297-306
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• 2008

In order to determine the effects of lock gate expansion at the Lake Youngsan and Yeongam as well as increase in the width of the connecting channel of the two lakes on flood control downstream of the Youngsan River, an unsteady hydraulic flood routing was conducted by combining the Lake Youngsan and Yeongam as a single connected system. The coupled operation of the two lakes was found to have little effect when the widths of the lock gates and the connecting channel are set at the current level. It was also found that increasing the width of the connecting channel as well as the lock gate of the Lake Yeongam is an effective means of reducing the stage of the Lake Youngsan, whereas an increase in the width of the Lake Youngsan's lock gate had a relatively smaller effect. The extended width of the connecting channel leads to a rise in the stage of the Lake Yeongam. In order to reduce the elevated stage, The Lake Yeongam's lock gate must be expanded along with the Lake Yeongsan's lock gate. The analysis found that the stage of the Lake Yeongsan can be effectively controlled through adjustment of opening and shutting criteria of the connecting channel's lock gate, when diversion discharge between the lakes is increased as a result of expanding the width of the connecting channel.

• Journal of Periodontal and Implant Science
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• v.29 no.3
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• pp.635-645
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• 1999

The present study examines the effects of orthodontic treatment of surgically exposed impacted upper canines or ectopically erupted upper canines to periodontal condition and whether various opening procedures have significant difference in postoperative periodontal status. The subjects included 23 orthodontic patients(7 men, 16 women) with unilateral upper canine impaction treated either with closed eruption technique(group I), with apically positioned flap procedure (group II), and those with canines ectopically erupted through keratinized gingiva (group III). In each subject, the ectopic canine was orthodontically aligned, and changes in periodontal tissue were assessed by measuring keratinized gingival width, attached gingival width, probing depth and bone probing depth. In all three groups, the width of keratinized gingiva was preserved while showed no signs of detrimental periodontal condition such as gingival recession. In all three groups, no significant difference in periodontal pocket depth from control was observed. The width of attached gingiva was significantly greater in patients treated with apically positioned flap procedure(group II) than in patients on other groups.

• Journal of Welding and Joining
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• v.24 no.5
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• pp.37-42
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• 2006

The robotic arc welding is widely employed in the fabrication industry fer increasing productivity and enhancing product quality by its high processing speed, accuracy and repeatability. Basically, the bead geometry plays an important role in determining the mechanical properties of the weld. So that it is very important to select the process variables for obtaining optimal bead geometry. In this paper, the possibilities of the Infrared camera in sensing and control of the bead geometry in the automated welding process are presented. Both bead width and thermal images from infrared thermography are effected by process parameters. Bead width and isotherm radii can be expressed in terms of process parameters(welding current and welding speed) using mathematical equations obtained by empirical analysis using infrared camera. A linear relationship exists between the isothermal radii producted during the welding process and bead width.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.5
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• pp.1227-1234
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• 1994

A cold spot temperature control system for the batch annealing furnace has been established in order to reduce energy consumption which is essential to improve productivity and stabilize the properties of products. A relationship between annealing cycle time and gas flow rate is developed and also for the variation of coil cold spot temperature with time during heating, and actual temperature measurements at mid-width of each coil during soaking. The results of the temperature variation effect on the cold rolled steel sheet batch annealing are as follows. (1) Cooling rate increasing gradually with increasing atmospheric gas flow, but heating rate is hardly increasing without atmospheric gas component change. (2) In case of short time heating, the slowest heating part is the center of B coil and in case of ling time heating, the low temperature point moves from the center of coil to inside coil. (3) The outside of top coil is the highest temperature point under heating, which becomes the lowest temperature point under cooling. (4) Soaking time determination depends on the input coil width, and soaking time for quality homogenization of 1214 mm width coil must be 2 hours longer than that of 914 mm width coil.

• Journal of the Korean Society of Marine Environment & Safety
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• v.13 no.4
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• pp.113-117
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• 2007

The study was performed on the development of system in which the bead width can be controlled. In order to control the bead width, we designed the automatic seam tracking device by attaching the probe type strain gauge sensor, motor driving slide and encoder to check the moving distance, and interface card connected MCU(80Cl96KC) upside the speed controllable carriage. Seam tracking experiments were done by changing the bead width. We compared and analyzed the sampling data which were obtained by output voltage of strain gauge sensor and rotary encoder pulse every 50ms.

• Korean Journal of Poultry Science
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• v.22 no.1
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• pp.7-13
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• 1995

To investigate the response of egg production to the artificial light to induce early egg laying. and the changes of egg weight and egg shape during the egg laying cycle, 30 Korean ring-necked pullets and their 1,284 eggs layed under artificial light control were used in this study. The first egg was ohserved at the age of 31 wk, after 4 wk of stimulating light(16 hour light: 8 hour dark). Egg production rate during seven 2-wk periods from the begining of the first egg was 43.7% and a clear peak egg production(61.7%) was shown at the 4th 2-wk period. The effects of egg production period and pullet on the egg weight, egg length, egg width and egg shape index(width/length) were significant(P<0.01). In the egg production cycle. egg weight, egg length and egg width increased steadly with time. but the value of egg shape index increased up to the 3rd 2-wk period and then decreased. Repeatabilities from intraclass correlation for the egg weight, egg length. egg width and egg shape index were 0.61. 0.53, 0.49 and 0.48, respectively.

• Laser Solutions
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• v.18 no.4
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• pp.17-22
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• 2015

In this paper, ablation rate of $Al_2O_3$ ceramics by femtosecond laser fluence is derived with experimental method. The automatic three axis linear stage makes laser optics to move with high spatial resolution. With 10 times objective lens, minimal pattern width of $Al_2O_3$ is measured in the focal plane. Ablated surface area is shown as linear tendency increasing number of machining times with various laser power conditions. Machining times is most sensitive condition to control $Al_2O_3$ pattern width. Also, the linear increment of pattern width with laser power change is investigated. In high machining speed, the ablation volume rate is more linear with fluence because pulse overlap is minimized in this condition. Thermal effect to surrounding medium can be minimized and clean laser process without melting zone is possible in high machining speed. Ablation volume rate decelerates as increasing machining times and multiple machining times should be considered to achieve proper ablation width and depth.

• Journal of The Korean Society of Integrative Medicine
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• v.1 no.2
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• pp.67-80
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• 2013

Purpose : This study was to investigate effects of closed kinetic chain and open kinetic chain exercise on the lumbar stabilizarion. Methods : A total of 30 healthy over 20 years old college students(men = 14, women = 16) who were participated in this. We selected randomly people of CKC, OKC, and control group. For the past four weeks, CKC and OKC group worked out 3 times per week and then we compared within group and between groups on muscle width. Results : 1. The width of internal oblique, transverse abdominis, and multifidus were all significantly increased after four weeks exercise in the CKC group(P<.05). 2. The width of internal oblique, transverse abdominis, and multifidus were all increased after four weeks exercise in the OKC group but transverse abdominis musule only showed significant difference. 3. Difference values between pre-exercise and post-exercise of transverse abdominis and multifidus in the CKC group was significantly high and difference among the groups were significant. Conclusion : Accordingly, lumbar stabilizing exercise was more effective to increase a width of abdominal deep muscles through CKC exercise.

• Journal of Welding and Joining
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• v.14 no.4
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• pp.33-42
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• 1996

In recent years there has been a significant growth in the use of the automated and/or robotic welding system, carried out as a means of improving productivity and quality, reducing product costs and removing the operator from tedious and potentially hazardous environments. One of the major difficulties with the automated and/or robotic welding process is the inherent lack of mathematical models for determination of suitable welding process parameters. Partial-penetration, single-pass bead-on-plate welds were fabricated in 12mm AS 1204 mild steel flats employing five different welding process parameters. The experimental results were used to develop three empirical equations: curvilinear; polynomial; and linear equations. The results were also employed to find the best mathematical equation under weld bend width to assist in the process control algorithms for the Gas Metal Arc Welding(GMAW) process and to correlate welding process parameters with weld bead width of bead-on-plates deposited. With the help of a standard statistical package program. SAS, multipe regression analysis was undertaken for investigating and modeling the GMAW process, and significance test techniques were applied for the interpretation of the experimental data.