• Proceedings of the KSR Conference
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• 2011.10a
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• pp.374-374
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• 2011

Recently the construction of railway sections passing the central area of cities and stations under railway lines are increasing, and then it is urgently required to take the countermeasures against the railway vibration and the second-phase noise radiated from it. The most efficient countermeasure, out of technologies developed up to now, is the floating slab track which is the track system isolated from the sub-structure by springs. In other countries, the source technologies for anti-vibration design and vibration isolator - one of key components - have been developed and many installation experiences have been accumulated. However, in Korea, since the system design technology and technologies for key components are not yet developed, the foreign system are being introduced without any adjustment, and the key component, vibration isolator, depends on imports. In this study, based on the results of previous studies of the dust-control device installation using the slab and go through time after lifting impressive when stepped on power generated by the cross-section of the slab and shear connection re-examined the structural stability.

• Journal of the Korean Society for Railway
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• v.15 no.6
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• pp.531-536
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• 2012

This study presents a result on aero-acoustic characteristics of pantograph panheads. To analyze the fluid flow around the panhead and resulting sound radiation, simple models of panhead were used in the numerical simulations called Lattice-Boltzmann method. The simulation results were verified using the wind tunnel test. The main aerodynamic noise was generated from the vortex shedding which is characterized by the Strouhal number, flow speed and geometry. The reduction in the radiated noise with simultaneously achieving increased lifting force was implemented for the simple rectangular geometry used in this study. Also, it was shown that the radiated sound power was significantly reduced by minimizing vortex shedding using through-holes or streamline shapes.

• Journal of Korea Society of Industrial Information Systems
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• v.6 no.3
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• pp.79-86
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• 2001

The CTD(Cumulative Trauma Disorder) as a new kind of occupational disease occurs mainly to workers on handling line under the highly-specialized industrial environments. This study took into account their exposure to Cumulative Trauma Disorders(CTD) by the utilization of EMG system, with respect to worker's muscle fatigue test according to fulfillment of iterative and simple task. The findings of this study were as follows : From the result of AEMG test analysis, worker's fatigue extent according to elapsed time of task was inclined to be increased continually. On the other hand, after its task ending, their fatigue extent was inclined to be decreased than before-circumstance of refractory brick lifting. The transference of MF(Median Frequency) and MPF(Mean Power Frequency) had highly significant difference between muscle fatigue and the elapsed time of work. Especially, their fatigue extent to erectorspinae and multifidus to lift firebrick was increased in the mean time. The transference of ZCR(Zero Crossing Rate) had considerable significant difference between muscle fatigue and the elapsed time of work. In short, as the work went of the muscle fatigue extent increased gradually. Thus, it can be concluded that the fatigue of erectorspinae and multifidus extent according to fulfillment of iterative and simple task is gradually being increased.

• Korean Institute of Interior Design Journal
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• v.25 no.5
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• pp.42-54
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• 2016

The purpose of this study is to provide a reference for stage planning by analyzing current state of major theaters' stage space and understanding feedback from directors belonged to theaters. Each room in total 18 theaters' stage facilities was measured and their usage and requirements were analyzed on the spot. In addition, each director provided their experiential knowledge about appropriate stage composition for musical performance. The findings are as follow: under stage machinery is not needed for musical. Tour teams prefer to use their own show-deck for set conversion. On the other hand, over stage flying system needs to be able to deal with dense, fast, and accurate scene change. The size and location of the motor room needs to be carefully considered. The number of set battens is directly linked up with the size of the motor room, which should be located lower than the gridiron. As stage sets get bigger and complicated, the number of works at the gridiron is also increasing. The grating floor has to have enough strength coping with machines lifting heavy sets. Most sound control for musical performance is being done at F.O.H. these days rather that in the sound control room. It should equip enough work area and related infra especially for tour teams. 1st gallery needs to have enough effective width, power infra for lighting fixture, and strong guardrail. Lastly, the whole process of parking-unloading-transporting equipments and sets from loading dock to stage and vice versa needs to be efficient, and this has to be carefully considered from early stage of planning.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.1
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• pp.124-133
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• 2017

In the current lighting market, LEDs that have a high luminous efficiency, a long life and consume less power have emerged as next generation lighting. Owing to various designs and sizes of LEDs, the production process of existing LEDs involves many tasks that require manual labor; hence, the assembly of LEDs necessitates manpower. Because of the use of manpower, the production costs of LEDs increases and production efficiency decreases. Recently, the assembly parts of LEDs have been standardized for minimizing manual labor, and an LED is developed as an LED panel. The automatic assembly system produces LED convergent lighting by assembling two LED panels and one diffusion cover. To increase the production efficiency of the LED convergent lighting module, it is important that the development of a feeder can continuously supply the LED panels is required, and whose design has sufficient stability. The automatic assembly system of the LED convergent lighting module consists of two feeders, which convey LED panels and diffusion covers to a main conveyor, which assembles the lifted panels and covers. In this study, structural analysis and fatigue life for forced loads on the conveyer line of the feeder in the process of lifting LED panels and diffusion covers of each feeder, is analyzed. In addition, the drive of the belt constituting the conveyor line of each feeder is simulated, and the dynamic characteristics of the belt is analyzed using the virtual engineering method.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.5
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• pp.1264-1271
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• 1990

The vortex lattice method was adopted to predict the aerodynamic performance of a horizontal axis wind turbine. For this simulation. the rotor blade was divided into many panels both in chordwise and spanwise direction and then replaced by horseshoe vortices. The wake was divided into two parts of near wake and far wake : the near wake was assumed as helical vortex line elements and the far wake was modeled by semi-infinite circular vortex cylinder. The induced velocity components were calculated by the Biot-Savart law. By this way the power coefficient was obtained and represented as a function of the tip speed ratio. The numerical results obtained were compared with those of the other methods and experimental results and showed good agreement with experimental results.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.38 no.4
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• pp.226-232
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• 2015

The aging of Korea is rapidly advancing in an unprecedented rate in the world. Indoor and outdoor safety accidents involving the elderly frequently occur, with elderly population increasing. Because the physical strength of elderly is decreased, it is necessary to develop devices that aid the everyday life of the elderly to prevent safety accidents. Among many activities, the motions of standing from and sitting on a chair require much physical strength from particular body parts, which causes an overload for particular body parts. To the elderly the repeating motion of standing from and sitting down on a chair is burdensome, because they do not have enough physical strength compare to young persons. As a result the elderly could be injured or falling during standing or sitting. Therefore, the development of a lift chair that considers the problems mentioned above is necessary to prevent the safety accidents of the elderly. The study designed a non-motorized lift chair that comfortably aids the standing and sitting down motion for the use of the elderly by reflecting the anthropometric data of the Korean elderly over 65 years old. Also the design was implemented to smoothly aid the standing motion by considering the knee angle of the elderly when standing. Because the regained strength to stand from a chair is depend on the knee angle. Unlike existing lift devices, this device utilizes a tilting mechanism that does not use electric power so that the product could be composed inexpensively than existing chairs released in the market.

• Journal of Drive and Control
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• v.18 no.4
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• pp.19-27
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• 2021

A bunker bed is a type of furniture that efficiently utilizes a narrow indoor space by having a high bed and using the empty space below as a living and storage space. The demand for multi-purpose furniture is increasing due to the recent increase in single-person households and wide-spread shared accommodation. According to the consumer research, one of the major drawbacks of a bunker bed was to get on and off the bed through a ladder or stairs. In order to overcome these problems, it was confirmed that the height adjustment function that can easily adjust the minimum and maximum heights of the bed was necessary. In this study, a height adjustable bunker bed was designed by using a gas spring that generates a repulsive force by the compressed gas inside. The design process consisted of the following three steps: Firstly, the hysteresis characteristics due to a friction and spring constant of a commercial gas spring were confirmed by measuring the repulsive force vs. compressed displacement. Secondly, requirements of the vertical lifting force exerted on the bed against gravity force were derived. Finally, the height-adjustable bed using the four-bar link mechanism was designed with 4 parameters so that the bed weight of 60-70 kgf could be adjusted to 800 mm in height by an affordable initial operation force. The performance was verified through prototype production and the results of vertical displacement and force to move were nearly the same as designed. In addition, an electrically operated height-adjustable bed was also designed with linear actuators and the performance was proved with the prototype.

• Journal of English Language & Literature
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• v.56 no.2
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• pp.219-236
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• 2010

As a poet, a reviewer of books, and an editor of a major literary journal, Marianne Moore participated in aesthetic revolution which invented the American poetry of the twentieth century. Of all the modernists, she was one of the few truly technical originals, and became an endearing mascot of poetry. Innately attentive to detail, Moore wrote a myriad of poems about animal and plant subjects, and set out to develope and secure her own particular paradigm for modernist poetic and the poetry of objective and scientific description. Foregrounding a mind scientifically trained, Moore used her verse to demonstrate a means by which to see the reality beyond the obvious. Ironically enough, however, a central difficulty with understanding Moore's poetry lies with her concern for such scientific or surface description and precision. In order to understand Moore's poetry fully, it is of special necessity to appreciate relativity among the seemingly disparate entities such as science and literature, as Moore herself did. This paper explores the way in which the poetic techniques of Moore substantiate her sense of morality that underlies the creation of her poetry. Rather than merely addressing her artistic genius or craftsmanship as a modernist poet, Moore's methods engage the power of imagination, magic, lifting the human spirit and eschewing anthropocentric perspectives. For Moore, the poet's magic comes by diligence. In so doing, as I would argue here, Moore draws on the nature of language, especially what Bakhtin insisted with his notions of polyphony and carnival. By introducing openness to various perspectives and meanings in her verse, Moore succeeds in maintaining her own sense of creativity while continuing to acknowledge morality. In a similar skein, her use of active verbs in animal poems and the kaleidoscopic descriptions demonstrate how Moore accommodates imagination and reality, and form and content.

• Journal of the Korean Applied Science and Technology
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• v.40 no.6
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• pp.1340-1349
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• 2023

Despite its profound impact on athletic performance, the significance of heart rate recovery (HRR) has been insufficiently addressed in the filed of sports science, particularly in the context of weightlifting characterized by brief and intense exertions involving heavy weights. Serving as a valuable indicator of autonomic nervous system and cardiovascular function, HRR assumes a pivotal role in weightlifting. This comprehensive review aims to delineate the specific demands for HRR in weightlifting, shedding light on the often overlooked cardiovascular considerations within training regimes focused on strength and power. The investigation scrutinizes the repercussions of HRR on weightlifting performance, seeking to elucidate how inadequate recovery intervals may result in physiological and psychological consequences. These consequences encompass a distorted perception of effort, disruption of coordination, compromised posture due to irregular breathing, and an overall decline in lifting capacity. The review systematically presents compelling evidence pertaining to heart rate response and recovery patterns during weightlifting, underscoring the critical importance of well-structured rest periods. Furthermore, the review delves into a comprehensive discussion of factors influencing HRR in weightlifting, encompassing variables such as sex, age, cardiovascular function, hydration, nutrition, and psychological aspects. Finally, a key emphasis is placed on the integration of effective HRR techniques into the training regimens of weightlifters, thereby ensuring sustained and optimized performance outcomes.