• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.7 no.2
• /
• pp.66-71
• /
• 2008

The data of the deformation and the stress according to time are studied at upper model of press and lower model of the blanking plate applied by press with the width, length and height of 0.4 m and 0.6 m respectively. The press is pushing downward on the plate fixed at the lower floor. These data are compared and investigated through this study. By using these results, there is the maximum deformation at 4 corners in the lower plate model of aluminium alloy fixed at lower floor. This deformation incase of elapsed time of 0.6 second becomes 4 times as much as in case of elapsed time of 0.2 second. The quantity of deformation at the lower plate model becomes more than at the upper press model to the extent of 10%. At the lower plate model of aluminium alloy, there is the maximum Von-Mises equivalent stress at 4 corners and both sides of middle area on the lower plate model of aluminium alloy. This stress in case of elapsed time of 0.6 second becomes 6 times as much as in case of elapsed time of 0.2 second. The Von-Mises equivalent stress of lower plate model becomes 2 times as much as that of upper press mode.

• Journal of Institute of Control, Robotics and Systems
• /
• v.13 no.7
• /
• pp.631-636
• /
• 2007

An efficient obstacle avoidance algorithm is proposed in this paper to avoid dynamic obstacles using a collision vector while a tele-operated mobile robot is moving. For the verification of the algorithm, an operator watches through a monitor and controls the mobile robot with a force-reflection joystick. The force-reflection joystick transmits a virtual force to the operator through the Inter-net, which is generated by an adaptive impedance algorithm. To keep the mobile robot safe from collisions in an uncertain environment, the adaptive impedance algorithm generates the virtual force which changes the command of the operator by pushing the operator's hand to a direction to avoid the obstacle. In the conventional virtual force algorithm, the avoidance of moving obstacles was not solved since the operator cannot recognize the environment realistically by the limited communication bandwidth and the narrow view-angle of the camera. To achieve the dynamic obstacle avoidance, the adaptive virtual force algorithm is proposed based on the collision vector that is a normal vector from the obstacle to the mobile robot. To verify the effectiveness of the proposed algorithm, mobile robot navigation experiments with multiple moving obstacles have been performed, and the results are demonstrated.

• Korean Journal of Agricultural Science
• /
• v.47 no.1
• /
• pp.95-104
• /
• 2020

The Ministry of Agriculture, Food, and Rural Affairs is currently pushing forward policies targeting the Rural Convergence Industry initiative to incubate the front-runners of the '6th industry', to increase off-farm income, to create rural jobs for elderly, and to create women-based farms. As a result, in 2017, a total of 11,604 Rural Convergence Industries were in business, and the goods produced from those industries were diverse. However, the quality and safety of those products are not being checked and managed thoroughly, which has caused consumers to not trust products made from the Rural Convergence Industries. Through a survey and the ordering logit model, this study analyzed consumer perception of the safety and quality of goods from the Rural Convergence Industries. The analysis revealed that we must first raise awareness of the importance of rural agriculture areas and the products of the Rural Convergence Industries to uplift consumer perceptions regarding the products produced by the industries. The analysis also revealed that diverse points of distribution (sellers), education on the importance of rural and urban areas, and marketing Rural Convergence Industry products within suburban consumer populations are necessary to increase the consumption of these products.

• 한국지구물리탐사학회:학술대회논문집
• /
• 2003.11a
• /
• pp.214-220
• /
• 2003

Pipe jacking is a name for a method to excavate a tunnel by pushing pipe into the ground from an especial pit. Size of tunnels in this method is different from under 900mm (microtunneling) to more than 3,000mm. Method of excavation is also different from hand digging to use of any kind of tunnel boring machines such as slurry and earth pressure balance (EPB) machines. Slurry pipe jacking was firmly established as a special method for the nondisruptive construction of the underground tunnels in urban area. During the pipe jacking and microtunneling process, the jacking load is an important parameter, controlling the pipe wall thickness, need to and location of intermediate jacking station, selection of jacking frame and lubrication requirements. The main component of the jacking load is due to frictional resistance. In this paper the skin friction between pipe surface and surrounding condition also lubricant quality based on a few fundamental tests, were considered. During this study unconfined compressive strength test, dynamic friction measurement test and direct shear box test were raised for one of the largest diameter slurry pipe jacking project in Fujisawa city in Japan. It could be concluded that in slurry pipe jacking, prediction of frictional forces are mainly dependent on successful lubrication, its quality and lubricant strength parameters. Conclusions from this study can be used for the same experiences.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.35 no.2
• /
• pp.88-97
• /
• 2012

The muscle strengths in various postures are still used in the workplace, although mechanization and automation have been continuously accomplished. The aim of this study is to measure the maximum muscle strength and analyze the muscle fatigue during the various wrench jobs which are one of the upper limbs related works. Four hundreds and eighty five college students (243 males and 242 females) participated in this study. Twelve muscle strengths which are using for pulling, pushing, lifting and lowering the wrench with various postures are measured. For every moment, the muscle strengths for both hands were measured. In each measurement, five seconds averaged value and peak value were collected. The averaged value of preferred hand and non-preferred hand was compared. Also, the averaged value of opposite movement was compared through t-test. The fatigue of agonist for each movement was analyzed using EMG analysis. The result of this study can provide some basic information not only in designing the tools in work but also in selection, training and management of workers.

• The Journal of Korean Physical Therapy
• /
• v.15 no.4
• /
• pp.34-45
• /
• 2003

A 'pusher syndrome' encompassing postural imbalance and hemi-neglect is believed to aggravate the prognosis of stroke patients. The patients with pusher syndrome show a particular posture that pushing away from the unaffected side of the body. The objective of this study was to investigate associated proprioception, associated neuro-psychological symptoms and characteristics of functional outcome with and without pusher syndrome. The subjects of this study were 58 acute stroke patients who been rehabilitated at two university hospitals in Seoul and Buchun. Data were collected using proprioception test and line bisection test. The ability of ADL was assessed by the Modified Barthel Index, transfer by the Functional Independence Measure, and balance by the Modified Motor Assessment Scale. The results were that significant difference was found in the presence of proprioception, in the incidence of hemineglect and anosognosia, and in the score of ADL, transfer and balance between patients with and without pusher syndrome. Patients without pusher syndrome gained more motor score than patients with pusher syndrome. From improvement of view, patients with pusher syndrome gained the lowest score in ability of transfer. The finding suggest that the patients with pusher syndrome is a poorer functional outcome, be related to proprioception, hemineglect and anosognosia.

• Journal of Korean Society of Rural Planning
• /
• v.19 no.3
• /
• pp.169-182
• /
• 2013

The purpose of this study is derived by Utilization Strategy for Rural empty houses stability of Return to the Farm and Rural. The main findings can be summarized as follows. First, the recent return to the farm and rural has increased, and life patterns of diversification, and the retirement of the baby boomer generation return to the farm and rural ratio differed by region. Second, the required first order accurate and detailed to maximize the utilization of the rural empty houses Survey, and the integrated management system based on it should be built. Third, the public lead in pushing for policy to take advantage of an empty house, leasing and management capabilities by strengthening return to the farm and rural characters, revitalizing rural and residential stabilization is necessary. Finally, in order to enhance the utilization of the rural empty houses should prepare return to the farm and rural, Multi-Habitation and a common space for existing residents for a variety of purposes. The results of these studies has a significance that can promote rural housing return to the farm and rural, resource utilization and stable settlement, and rural areas activated at the same time. Utilization of specific rural empty houses feasible policy being prepared, by linking rural areas that can bring effects on the activation of alternative hope.

• Journal of Oriental Neuropsychiatry
• /
• v.11 no.1
• /
• pp.47-57
• /
• 2000

This study was designed and performed to identify the effects of oriental medical therapy on hwabyung patients by investigating the life events as the cause of Hwabyung, recent stress perception which influences the clinical appearances and change of symptoms by means of objective scales. 1. Through life events rating scale, life events are reported as follows, in the order of majority. Health, discord within family, martial life, friendship and interest, religion etc. Hwabyung patients experienced negative stress much more than positive stress. 2. Through the GARS (Global Assessment of Recent Stress), there were some significant decreases of stress perception in stress4(stress of sickness or injury), stress7(stress of change or no change in routine) and stress8(overall global stress)(p<0.05, respectively), but there were no significant decreases in five items out of eight items. 3. There were significant decreases of all rated symptoms(feeling of chest oppressed, stuffy in the chest or epigastric mass, feeling of something pushing-up, flushing of body or face, abrupt impulsion of anger, resentment), which were checked weekly for 4 times (p<0.05, respectively). In this study the symptoms of hwabyung were improved regardless of stress perception. It means that hwabyung can be improved significantly with oriental medical therapy.

• Korean Journal of Applied Biomechanics
• /
• v.20 no.3
• /
• pp.319-325
• /
• 2010

The purpose of this research was to investigate the differences in the ski carving turn motion according to level of expertise. The posture and movement of 6 skiers nearby the fall-line was evaluated with a biomechanical approach focusing the rotational mechanics. The slope was at an angle of $9^{\circ}$ and the following variables were measured and calculated: tangential velocity, change of COM height after passing fall-line, width between feet, angle between upper body and thigh, trunk angle, average radius of curvature and average centripetal force. The expert skiers minimized their center of mass height movement and maintained the width of between their feet after the passing the fall-line in comparison with the beginners and intermediate skiers. The experts restrained themselves from pushing their upper body downward after the turn to maximize the centripetal force. The experts in comparison with the beginners and intermediate skiers during the turn didn't have to reduce their radius of curvature to maintain a high centripetal force. It was concluded, that the most important factor affecting the centripetal force, was for the beginners and intermediate skiers, to minimize their movement while using the appropriate amount of edging.

• Korean Journal of Child Studies
• /
• v.35 no.5
• /
• pp.63-82
• /
• 2014

The purpose of this study is to elucidate how two young children understand force in rough-and-tumble play. For this purpose, a form of microanalysis(Forman, 2006) was used. They regarded black as the strongest color due to their daily experiences. They assumed that a structure made of black Lego-color-bricks would be strongest and made an experiment of beating it against blocks of other colors. Such repetitive behavior ultimately led them to realize that color had no correlation with strength. They also understood mechanical energy by which a boy's pushing power moves against an object. They tried to strike a bigger or protruding structure and understood that parts might be broken more easily by striking. This experience enabled the boys to realize the principle of resistance. That is to say, in the process of rough-and-tumble play, their misconceptions were gradually removed and they obtained scientific knowledge, including understanding of mechanical energy and the principle of resistance. This study found that two young children constructed knowledge together through the process of tool making and in contending for victory in rough-and-tumble play.