• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.697-700
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• 1999

Strengthening existing structure using the exterior steel wire is utilized because of their high adaptability and strengthening efficiency. In the practical aspect, the fixing methods, which are generally adopted have caused problems. A new method is not easily designed because of the weak points, a limit of tension stress, and complex transmit processes. To make up for the weak points in the current fixing method, tensile end bracket similar to a supporting plate has been developed, but the tensile end bracket was relatively big because of increasing length welded between the end plate and the resisting plate.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.219-222
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• 2007

The Full-Off Fitting of Movable Bracket using conventional line have received a dynamic contact impact between contact wire and pantograph of electric rolling stock, so this impact cause a rapid vibration of foreword and back near the supporting point of movable bracket. The Full-Off Fitting on Movable Bracket in conventional line differs from that in high speed line. Now conventional line have required a speed up for new electric locomotive and electric car. In speed-up track and big impact place, the Full-Off Fitting and the dropper often get demage. We have done a study of buffering function to solve that problem in conventional line. We have find a need adopting buffer fitting. It is decrease a dynamic impact between contact wire and pantograph of electric rolling stock.

• Special Issue of the Society of Naval Architects of Korea
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• 2005.06a
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• pp.63-68
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• 2005

Optimum design of the big brackets is performed through iterated 3-D FE analyses to meet the permissible limits of stress, which consumes an excessive amount of calculation time. Therefore, this study has been prepared to determine rapidly and accurately an optimum size and scantling of the big brackets at the initial design stage. The generalized slope deflection method (GSDM) based on the span point concept is applied to enhance the efficiency of iterated structural analyses. The accuracy and applicability of the present method is verified by comparing with a detail 3-D FE analysis of web frame structures. As an optimization technique, evolution strategies (ES) are applied using discrete design variables for practical design.

• The korean journal of orthodontics
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• v.28 no.4 s.69
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• pp.641-657
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• 1998

This study was undertaken to compare the bond strength and the fracture site of new and recycled brackets according to the base design. 252 sound premolars extracted for orthodontic treatment were collected and Type I, Type II, Type III brackets were divided into four groups by recycling method Each bracket was then bonded to an extracted premolar. Instron Universal Testing Machine(model W) was used to measure the shear bond strength, and the surface of the recycled brackets were viewed in SEM For the analysis of the results, one way ANOVA and Scheffe's multiple range test was executed using the SPSSWIN program. 1. The shear bond strength showed statistically significant difference according to the bracket base design(p<0.001). Type III bracket(round indentation base, micro-etched) showed the highest bond strength, Type I bracket(foil-mesh base) was second, and Type II bracket(grooved integral base, micro-etched) was last. 2. The effect of recycling on the bond strength was different according to bracket type. The shear bond strength of Type I, Type II brackets showed the smallist reduction when treated for 1 minute in Big Jane(p<0.05), but the shear bond strength of Type III brackets showed no statistically significant difference according to recycling method(p>0.05). 3. In Type I, Type II brackets, frequent fracture site was bracket-resin interface, but in Type III brackets, about half of the resin was retained on the tooth surface frequently. 4. The shear bond strength was highest when about half of the resin was retained on the tooth surface(p<0.05). 5. The resin remnant on the bracket base after recycling had no effect on the shear bond strength.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.6
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• pp.205-212
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• 2003

This paper may provide a basic design data for the safer car seat mechanism and the quality of the material used by finding out the passenger's dynamic behavior when protected by seat belt during collision. A computer simulation with finite element method is used to accomplish this objective. At first, a detailed geometric model of the seat is constructed using CAD program. The formation of a finite element from a geometric data of the seat is carried out using Hyper-Mesh that is the commercial software for mesh generation and post processing. In addition to seat modeling, the finite element model of seat belt and dummy is formed using the same software. Rear impact analysis is accomplished using Pam-Crash with crash pulse. The part of the recliner and right frame is under big stress in rear crash analysis because the acceleration force is exerted on the back of the seat by dummy. The stress condition of the part of the bracket is checked as well because it is considered as an important variable on the seat design. Front impact model which including dummy and seal belt is analyzed. A Part of anchor buckle of seat frame has high stress distribution because of retraction force due to forward motion of dummy at the moment of collision. On the basis of the analysis result, remodeling and reanalysis works had been repeatedly done until a satisfactory result is obtained.

• Special Issue of the Society of Naval Architects of Korea
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• 2005.06a
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• pp.84-89
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• 2005

The double hull VLCC(Very Large Crude Oil Tanker) have been designed to have each four(4) longitudinal bulkheads and transverse bulkheads in general. Actually, the inside longitudinal bulkheads among four(4) longitudinal bulkheads, which are extended up to the end of the aft cargo hold for continuity of the members, have been designed with knuckled type inboard due to the narrowed hull shape at bottom region, but sometimes the straight type of longitudinal bulkheads were adopted based on the degree of the hull lines shape. However, regardless the type of longitudinal bulkheads, inside and outside longitudinal bulkheads conflict each other in aft cargo hold region This makes the structure more complex thus giving difficulties to structural design and production. Recently, a vessel of straight type was reported to have cracks on bracket end and tripping bracket toe in aft cargo hold region. As a solution to this problem, in designing the first 60m Beam VLCC, DSME developed a new cargo hold structure which is good in production and structural point of view by structural strength and fatigue analysis of fore and aft cargo hold.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.1009-1014
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• 2001

This study is to develop the end anchorage of external steel reinforcement of RC slab bridges. External prestress method using the existing steel is that When the anchorage is installed in slab end, a plenty of anchor bolts were required because the only tangential stress of anchor bolt received a tendon force. Then, for this reason, the wide end anchorage was required and the shape was complicate. But this reinforcement method using method that inserts anchor key at concrete surface cut a groove gets big internal force comparing to the anchorage using existing anchor bolt. Furthermore, the number of anchor bolt for installing apparently will be reduced, and the operation will be convenient because a small anchorage of a simple shape will be received a great tendon force.

• Journal of Auto-vehicle Safety Association
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• v.13 no.3
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• pp.60-68
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• 2021

Invisible passenger airbag door system of hard panel types must be designed with a weakened area such that the side airbag will deploy through the instrument panel as like intended manner, with no flying debris at any required operating temperature. At the same time, there must be no cracking or sharp edges in the head impact test. If the advanced airbag with the big difference between high and low deployment pressure ranges are applied to hard panel types of invisible passenger airbag (IPAB) door system, it becomes more difficult to optimize the tearseam strength for satisfying deployment and head impact performance simultaneously. It was introduced the 'Operating Window' idea from quality engineering to design the hard panel types of IPAB door system applied to the advanced airbag for optimal deployment and head impact performance. Zigzab airbag folding and 'n' type PAB mounting bracket were selected.

• Journal of the Korean Society of Clothing and Textiles
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• v.41 no.4
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• pp.722-740
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• 2017

This study was conducted to offer basic data that can be used in a clothing industry for active senior males that are emerging as a new consumer bracket in a rapid aging age. To this end, this study conducted an analysis of 'younger' older male body types based on data from the 6th Size Korea. As a result of the body type analysis of 'younger' older males who are considered active seniors in comparison to 'middle' aged males, the former's height items became shorter compared to 'middle' aged males, but circumference items were bigger. Males aged 35-69, who are 'middle' aged males and 'younger' old males were divided into three body types in this study: Type1- small body type with protruded belly, compared to weight. Type 2- body type of slim torso with wide shoulder-back widths. Type3- big body type overall with tall height and heavy weight. According to body type distribution by age group, the middle-aged males had Type2 body type the most. The younger-old males showed type1 the most. There is a need to reflect the body types of active senior male characteristics in apparel pattern design because the current fits are not appropriate if active senior males wear clothing targeted for males aged 30-50.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.489-497
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• 2000

Since Chinese cabbages weigh 3 to 5kgf and are big in size at the time of harvest, handling operations such as harvesting, loading and unloading including transportation require the highest labor demand among all other cultivation processes. Recently, though several cabbage harvesters were developed in Japan and Europe, those harvesters were not suitable for Chinese cabbages cultivated in Korea because of the size and shape. The cabbage harvester is almost meaningless without any proper cabbage piling and pallet unloading mechanism. Most harvesters developed so far adopted a sort of slide and free falling way in collecting cabbages into the pallet. Three or four labors are usually required for cleaning incoming cabbages and loading those in the pallet. Because of the required time for piling cabbages without severe damage and the required space capacity to carry empty and loaded pallets, harvesting speed should be adjusted in accordance with time required for consecutive operations. Up to now, any automatic or semi-automatic collecting device has not been developed in the world to pile cabbages on the layer one by one into the pallet in the ordered way with little damage and to unload pallet from the harvester continuously during the harvest process. To compromise system expenses and function, Semi-automatic cabbage piling and pallet unloading mechanism was devised and it required one labor. The foldable mesh pallet with a size of 1050mm x 1050mm x 1000mm and holding capacity of around 70 cabbages was utilized. The prototype for piling and unloading mechanism was composed of three parts such as feeding device, automatic piling device with retractable bellows, and pallet unloading device. Prior to developing the prototype, the geometric properties and the amount of the damage of the cabbage caused during the piling operation were investigated. Considering the height of the pallet, a series of cabbage carrying plates were mounted to the bracket chain to lift and to carry cabbages to the loading device. Indoor laboratory experiments showed that the cabbage carrying chain conveyor worked successfully. Considering the conveying speed 0.46m/sec of the pull up belt from the cabbages on the ground, the speed of cabbage carrying chain conveyor worked property in the range of 0.26m/sec to 0.36m/sec. The system allowed the operator to modify the position of cabbage slightly. Overall system worked successfully resulting into almost same capacity without severe damage to the cabbage as human did.