• Journal of the Korean Society of Industry Convergence
• /
• v.22 no.3
• /
• pp.273-280
• /
• 2019

Carbon fiber composite laminate has been widely used in the area of sports applications such as race car, golf club, fishing rods, yacht. In this study, carbon fiber composite laminate was used in the rear upright of leisure purposed small size single-seat electric race car to reduce its unsprung mass of suspension system. The focus of this research is to investigate in finding optimal stacking lay-up of rear upright laminated with carbon fiber composite in the early design phase. Forces transferred from circuit road to rear upright were estimated through MBD(Multi-Body Dynamics)model of the rear suspension geometry. To evaluate the strength of the rear upright laminated with carbon fiber composite which generally behaves in an anisotropic or orthotropic manner, FEA(Finite Element Analysis) model suitable for composite materials was built followed by its strength was evaluated depending on different stacking lay-up. The result showed that Symmetric stacking lay-up [$45^{\circ}/-45^{\circ}/90^{\circ}/0^{\circ}$]s for frontal area and symmetric stacking lay-up with 1mm aluminum core [$45^{\circ}/-45^{\circ}/90^{\circ}/Core$]s for rear area were most suitable of 16 lay-up cases from the side of both strength based on Tasi-wu failure index and weight.

• Korean Journal of Agricultural Science
• /
• v.46 no.2
• /
• pp.341-350
• /
• 2019

Garlic is one of the most popular seasoning bulb vegetables in Korea and is the most commonly used food ingredient. However, the cultivation areas are decreasing every year as the price drops due to imported garlic, and labor is insufficient to produce garlic by conventional methods. Cultivation requires various tasks until garlic is harvested. Seeding is one of the important and laborious tasks; thus, mechanization is necessary. When seeding garlic, the sprout should face upwards; otherwise, it may rot or produce poor quality garlic. This study investigated the extent of growth of northern- and southern-type garlic in eight different positions. The results show when the roots were not planted properly, the stems were weak, and the garlic bulbs were small. A simple garlic planter was manufactured with a crank-press mechanism to plant garlic in an upright position. Using this machine, a three-fold experiment was carried out with 100 strips of garlic. The test results showed that 99.4% of the planted garlic strips were positioned upright or close to being upright, and 0.6% failed to take root. An image processing algorithm was developed to locate the root part of the garlic, and the result showed a success rate of 81%. A future study will develop an automatic garlic upright planting system with a viewing system.

• Korean Journal of Applied Biomechanics
• /
• v.26 no.3
• /
• pp.285-292
• /
• 2016

Objective: This study collected data on muscle fatigue and ground reaction force during walking to provide a basis for development of custom-fitted outdoor walking shoes. The study analyzed an upright body exercise program using spine stabilization technique to determine the effect on foot plantar pressure in archers, demonstrate the effectiveness of upright body exercise, and develop a new, effective, and efficient training program. Method: A 12-week upright body exercise program was evaluated for the effect on plantar pressure in archers. Ten prize-winning archers (3 men, 7 women) in B metropolitan city, each with ${\geq}10years$ of experience, were given an explanation of the content and purpose of the program, and provided informed consent. Upright body exercise was performed 3 times a week for 12 weeks. A resistive pressure sensor was used to measure foot plantar pressure distribution and analyze quantitative information on variation in postural stability and weight shifting in dynamic balance during shooting, as well as plantar pressure in static balance with the eyes open and closed. Results: There were no significant differences in foot plantar pressure before and after participation in the exercise program. There was no statistically significant difference in foot plantar pressure in static balance with the eyes open or closed, or in foot plantar pressure in dynamic balance during shooting. Conclusion: An upright body exercise program had positive effects on foot plantar pressure in static and dynamic balance in archers by reducing body sway and physical imbalance during shooting and with eyes closed. This program is expected to help archers improve their posture and psychological state, and thereby improve performance.

• Korean Journal of Applied Biomechanics
• /
• v.28 no.1
• /
• pp.9-18
• /
• 2018

Objective: This study aimed to analyze how the upright body type exercise program affected body balance and record of archers. This study aimed to prove the effectiveness of upright body type exercise, on this basis, in enhancing the performance of archery players. Method: A total of 14 archers (7 men and 7 women) in B Metropolitan City who had ${\geq}4years$ of career in archery and were given explanation of its contents and purpose before giving spontaneous consent to the experiment were enrolled in the study. The upright body type exercise program was implemented thrice a week for 12 weeks, with higher exercise intensity with time. A resistive pressure sensor, Gaitview AFA-50, was used to measure the foot plantar pressure distribution and analyze quantitative information concerning variation in posture stability and weight shift in dynamic balance of foot plantar pressure in shooting and static balance of plantar pressure with the eyes open and closed and the change in archery record accompanying the change in body balance. Results: As for the differences in foot plantar pressure between before and after participation in the upright body type exercise program, there was no significant difference in static balance of foot plantar pressure with the eyes open, and there was statistically significant difference at the ${\alpha}=.05$ significance level in static balance of foot plantar pressure with the eyes closed or in dynamic balance of foot plantar pressure in shooting. There was statistically significant difference at the ${\alpha}=.05$ significance level in archery record. Conclusion: The upright body type exercise program had positive effects on static and dynamic balance of foot plantar pressure by allowing archers to experience less body sway and physical imbalance in shooting with closed eyes and positive effects on archery record. Thus, the program is expected to help archers correct their posture and perform better.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.22 no.1
• /
• pp.112-118
• /
• 2013

Formula race car is generally recognized as a vehicle which is optimally designed for on-road race track with the regulations of race host bodies. Especially, the uprights of suspension system decisively have effects on the performance of cornering and stability of race car's driving performance, which are very important factors in the design of race car. This paper is a study of optimal upright design of F1800 grade formula race car which are normally used in professional race circuit in Korea. To design optimally the front upright of F1800 formula race car, Taguchi's orthogonal array, which is known for more useful method than full factorial design experimental method in cost and time, is used with CAE method such as FEM analysis. And the result of this paper shows that Taguchi's orthogonal array employed for this optimal design is very useful for designing the front upright of race car by minimizing its weight as well as keeping its safety factor as enough as designer wants in the view of quality, cost and delivery at the early design step.

• Journal of the Ergonomics Society of Korea
• /
• v.5 no.1
• /
• pp.3-9
• /
• 1986

This research is aimed at examining age-related changes of postural sway when people stand upright, examining external effects which can be exerted upon the postural sway (experiment 1), and also analyzing specific changing characters of posture-control by sudden impacts (experiment 2). The total number of subjects was 115, who are in twenties through seventies and 75 of them were participated in experiment 2. In experimen 1, the subjects were examined for 25 seconds respectively while standing upright with both feet and with eyes opened, standing upright with both feet and with eyes closed, and standing upright with a single foot and with eyes opened. In experiment 2, only while standing upright with both feet and with eyes opened they were examined for 5 seconds. Main findings were as follows: 1. In the single-foot standing position, the growing older exerted more important effects upon the fluctuation length and area of the center of gravity than in the both-foot standing position. 2. The standard deviation was increasing with age in the fluctuation length and the fluctuation area of the center of gravity. 3. There were no significant differences in daily variation, temperature change, and muscle burdening. 4. The recuperation from the postural sway by external impacts was so slow with age. 5. There were little differences in decrease frequencies among the subjects but younger persons.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 2000.11b
• /
• pp.438-445
• /
• 2000

Positioning garlic cloves in upright standing in garlic field has been regarded as a very important job because it affects clove rooting, growing and, eventually, quality and yield in garlic production, Because of the geometrical uniqueness and irregularity of garlic cloves in shape, the planting operation has been conducted by manual work that needs a tremendous human labors and increases garlic production cost. The overall objective of this research was to develop garlic planting machine through investigating physical properties of garlic and designing clove upright positioning device after figuring out the factors affecting metering device and upright clove positioning mechanism. With the outcomes of the metering and posture positioning experiment, a garlic clove planter having twelve planting rows was developed for 37kW type tractor and feasibility test was carried out in the field. And, According to the performance test and cost analysis, the planter could accomplish planting operation of one hectare plot in 6.3 hours giving 48 times better efficiency, 6.3hrs/ha, and 74.2% of production cost reduction effect, 1,092,546won/ha, than the manual works of 299hrs/ha and 282,258won/ha. And, break-even point ofthe planter was calculated as of 2.71 hectares.

• Journal of ILASS-Korea
• /
• v.28 no.2
• /
• pp.97-104
• /
• 2023

A sprinkler is a fire suppression system that extinguishes combustible materials in the early stages of a fire, creating a spray. However, spray formation method of the sprinkler can result in an uneven distribution of water spray on the surface of combustible materials. It is necessary to ensure a consistent water flux density regardless of the spray direction and angle. In this study, the water flux distribution was analyzed for the various types of sprinkler head: circular, flush, pendent, and upright types. All sprinkler heads have a K-factor of 80 LPM/(0.1MPa)^0.5. In this study, water collection cubes were used to examine the water flux distribution. The upright type sprinkler head showed a low standard deviation in total sprayed area, indicating a high level of uniformity. The upright type head showed the lowest standard deviation in the radial direction, and also showed the lowest standard deviation in the azimuthal direction. Upright sprinkler head has no obstructing structure along the path of droplets after they are generated. For this reason, upright sprinkler head showed the most uniform water flux distribution on the floor.

• Steel and Composite Structures
• /
• v.3 no.5
• /
• pp.307-320
• /
• 2003

This paper presents an efficient approach to the determination of the buckling loads of down-aisle, spliced, unbraced, pallet rack structures subjected to vertical and horizontal loads. A pallet rack structures is analysed by considering the stability equations of an equivalent free-sway column. The effects of semi-rigid beam-to-upright, splice-to-upright and base-plate-to-upright connections are fully incorporated into the analysis. Each section of upright between successive beam levels in the pallet rack is considered to be a single column element with two rotational degrees of freedom. A computer algebra package was used to determine modified stability equations for column elements containing splices. The influence of the position of splices in a pallet rack is clearly demonstrated.

• Physical Therapy Korea
• /
• v.20 no.2
• /
• pp.20-27
• /
• 2013

The purpose of this study was to compare the slouched and upright sitting positions on lumbar joint reposition error (LJRE). Twenty subjects without low back pain were recruited for this study and, using a random number table, were randomly assigned to two groups; the upright sitting position group (UP group) and the slouched sitting position group (SP group). UP group was first asked to sit in an upright position and the SP group to sit in a slouched position as an intervention, and then the LJRE of both groups was measured at the neutral sitting position (lumbar flexion $0^{\circ}$). The measurement of the LJRE was repeated after one day. The sitting positions were performed for five minutes each and the LJRE was measured using an electronic goniometer. An independent t-test was used to compare the LJRE of both groups after each sitting position and after one day. The results of this study showed that the LJRE after an intervention in the UP group was lower than in the SP group (p<.05) and the LJRE after one day in the UP group was lower than in the SP group (p<.05). The findings of this study indicate that the upright sitting position can be applied to decrease LJRE, compared with the slouched sitting position. These findings also support that the upright sitting position reduces the potential for proprioceptive loss.