• Korean Journal of Applied Biomechanics
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• v.31 no.4
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• pp.308-313
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• 2021

Objective: The purpose of this study was to investigate the effect of different kettlebell mass (30%, 40%, and 50% of the body mass) on kinematics and kinetic variables of kettlebell swing. Method: Total of 16 healthy male who had at least 1 year of kettlebell training experience were participated in this study (age: 31.69 ± 3.46 yrd., height: 173.38 ± 4.84 cm, body mass: 74.53 ± 6.45 kg). In this study, a 13-segments whole-body model (upper trunk, lower trunk, pelvis, both side of forearm, upperarm, thigh, and shank) was used and 26 reflective markers were attached to the body to identify the segments during the movement. A 3-dimensional motion analysis with 8 infrared cameras and 4 channeled EMG was performed to find the effect of kettlebell mass on its swing. To verify the kettlebell mass effect, a one-way ANOVA with a repeated measure was used and the statistical significance level was set at 𝛼=.05. Results: Firstly, in all lower extremity joints and thoracic vertebrae, a statistically significant change in angle was shown according to an increase in kettlebell mass during kettlebell swing (p<.05). Secondly, in both the up-swing and down-swing phases, the knee joint and ankle joint ROM showed a statistically significant increase as the kettlebell mass increased (p<.05) but no statistically significant difference was found in the hip joint and thoracic spine (p>.05). Lastly, the hamstrings muscle activity was statistically significantly increased as the kettlebell mass increased during up-swing phases (p<.05). Also, as the kettlebell mass increased in P4 of the down swing phase, the gluteus maximus showed a statistically significantly increased muscle activation, whereas the rectus femoris showed a statistically significantly decreased muscle activation (p <.05). Conclusion: As a result of this study, hip extension decreased and knee extension increased at 40% and 50% of body mass, and the spine also failed to maintain neutrality and increased flexion. Also, when kettlebell swings are performed with 50% of body mass, synergistic muscle dominance appears over 30% and 40% of body mass, which is judged to have a risk of potential injury. Therefore, it is thought that for beginners who start kettlebell exercise, swing practice should be performed with 30% of body mass. In addition, even in the case of experienced seniors, as the weight increases, the potential injury risk may increase, so it is thought that caution should be exercised when performing swings with 40% and 50% of body mass. In conclusion, it is thought that increasing the weight after sufficiently training with 30% of the weight of all subjects performing kettlebell swing is a way to maximize the exercise effect as well as prevent injury.

• Cross-Cultural Studies
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• v.46
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• pp.411-434
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• 2017

With emphasis on various local cultures to confront the Western central culture, Ngugi wa Thiong'o proposes them 'to move horizontally' so as not to repeat the oppressive culture of the West. We need not only dialogues between dominant languages and peripheral languages, but also between marginal languages. With respect to this point, Ngugi thinks that translation itself could be very effective. Ngugi wants to stimulate writing and speaking in marginalized languages and promote translation as a means of making these languages visible. He regards translation as a conversational tool among languages and cultures in the multicultural global community. As is already well known, his determination to write his later works only in his native Gikuyu language has a great meaning in his anti-colonial as well as anti-neocolonial movement. Its proof is his recent effort to cooperate with Jalada Africa. Simon Gikandi criticized the English translation of Matigari as a denial of cultural hegemony of Gikuyu language and its subordination to the global cultural market. However, the concept of 'thick translation', helps us move from Gikandi's doubt of the 'epistemology of translation' to a meaningful strategy of postcolonial translation. Facing some of the scholars' doubts related to his over-stressing language problem, Ngugi points out that the world has managed to function well through translation: the possibility of translation between cultures and translation as a mediating tool for communication nationally as well as internationally. Based on this two-sided solution of translation, he believes that we can overcome the opposition between relativity and universality, center and periphery, and the dominant and the subordinate.

• The Korean Journal of Archival Studies
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• no.3
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• pp.3-32
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• 2001

In this paper, local public archives is referred to the public archives of provincial governments and metropolitan city governments as defined in the public Records Management Act. Under the Act, as professional archives, the local public archives preserves records designated as permanent preservation which the local government and its sub-agencies created or received to conduct public business. The Act also allows local public archives to establish an appropriate basic plan to manage its holdings as well as to oversight its sub-agencies. The Act stipulates that the local public archives are to be established in all provinces and metropolitan cities. The local public archives shall preserve archival heritage safely and utilize use of the recorded information as defined in the Article one of the Act. The local archives shall respect the principle of provenance. It is expected that the local archives shall strengthen local archival promotion campaigns which necessarily reflect unique local circumstances. However, as the Act just recommended the establishment of local public archives not to force as a mandatory procedure, it resulted in a flow of some confusions and misinterpretations. Despite the act was proclaimed two years ago, the local public archives are not yet established, not to mention that no preparatory works are on the way. To establish the local public archives effectively which meet local residents needs and demands, provincial governments and metropolitan city governments should proceed a well-prepared preparatory works plan considering the steps to transform them into the local public archives when they establish agency records centers. The first step in this process is to reach at a common consensus on the functions and roles of the local public archives which accommodates local residents needs and demands. Secondly, by analyzing the functions of archives to be established, an estimation of needed human resources, facilities, equipments, organization, budget appropriation, and local rules should be performed. Otherwise, the establishment of decent local archives is a far remote future. One of the methods to proceed this project systematically is to establish a local research institute for the local archives and cultural studies which would be put under the local university authority while consulting with local governments, local civil organizations, local historical and cultural societies. It is very undesirable to stress too much upon administrative efficiency when concerned parties discuss the functions and roles of the local public archives. They must keep in mind that when the functions to collect and use historically valuable records are active then administrative efficiency can be raised as well as accountability. Collecting and arranging historically valuable records is a short-cut way to promote accountability and develop local political culture. The local public archives is a valuable community historical center and an effective medium to facilitate historical speaking and writing among local people, something more than a simple public archives. Then our campaign for the establishment of local public archives can be a meaningful political cultural movement.

• Journal of Technology Innovation
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• v.27 no.2
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• pp.1-36
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• 2019

In line with the international community's movement to reduce greenhouse gas emission, Korea implemented FIT(Feed in Tariff) in 2002 as part of its renewable energy development project. Although the policy had shifted to full-scale RPS(Renewable Portfolio Standards) in 2012, policymakers are still seeking changes due to policy ineffectiveness. While previous studies explain sudden policy changes through external factors, recent research sheds light on internal factors in the process of policy transition. The purpose of this study is to investigate the factors that are responsible for rapidly changing policies in latecomer nations. In order to find this, we look at the case of transition from the FIT to the RPS in Korea's expansion of renewable energy policy. As a result of the research, it is confirmed that the Top-Down decision making system of Korea and the external regulatory change cause rapid policy transition. By looking at these variables, we propose useful implications for policymakers to minimize the policy failure in future policy design and evolution.

• Korean Journal of Applied Biomechanics
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• v.31 no.2
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• pp.133-139
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• 2021

Objective: This study aims to verify the conventional deadlift motions using by two different grips, thereby elucidating the grounds for effective training methods that can minimize the risk of injury. Method: Total of 18 healthy young adults were recruited for this study (age: 25.11±2.19 yrs., height: 175.67±5.22 cm, body mass: 78.5±8.09 kg, 1-RM: 125.75±19.48 kg). All participants were asked to perform conventional deadlift with two types of grips which are overhand grip (OG) and underhand grip (UG). In each grip, participant perform the deadlift with 50% and 80% of the pre-measured 1-RM. A 3-dimensional motion analysis with 8 infrared cameras and 3 channels of EMG was performed in this study. A two-way ANOVA (group × load) with repeated measure was used for statistical verification. The significant level was set at α=.05. Results: There were significant differences in grip type and weight on the right shoulder joint, and only significant difference in grip on the left shoulder joint (p<.05). The hip joint ROM was significantly increased as the weight increased in both types of grips on phase 1, while the ROM of hip joint was significantly decreased as the weight increased only in the case of OG on phase 2 (p<.05). In case of the OG, as the weight, increased significantly increased L1 ROM and L3 ROM were revealed on phase 1 and phase 2, respectively (p<.05). Moreover, as the weight increased, UG revealed significantly decreased L5 ROM on phase 1, while both grips showed significantly increased ROM on phase 2 (p<.05). In addition, the erector spinae and the biceps femoris, which are synergist for the motion, showed a significant difference in both types of grip according to the weight (p<.05). The muscle activity ratio of gluteus maximus/biceps femoris showed a significant difference only in the UG according to the weight (p<.05). Conclusion: In conclusion, beginners might be suggested to use the UG for maintaining the neutral state of the lumbar spine and focus on the gluteus maximus muscle, which is the main activation muscle. For the experts, it may recommend alternative use of the OG and UG according to the training purpose to minimize the compensation effect.

• Korean Journal of Applied Biomechanics
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• v.32 no.1
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• pp.17-23
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• 2022

Objective: The aim of this study was to investigate the effect Tiger-step walking on the movement of the lower extremities during walking. Method: Twenty healthy male adults who had no experience of musculoskeletal injuries on lower extremities in the last six months (age: 26.85 ± 3.28 yrs, height: 174.6 ± 3.72 cm, weight: 73.65 ± 7.48 kg) participated in this study. In this study, 7-segments whole-body model (pelvis, both side of thigh, shank and foot) was used and 29 reflective markers and cluster were attached to the body to identify the segments during the gait. A 3-dimensional motion analysis with 8 infrared cameras and 7 channeled EMG was performed to find the effect of tigerstep on uphill walking. To verify the tigerstep effect, a one-way ANOVA with a repeated measure was used and the statistical significance level was set at α=.05. Results: Firstly, Both Tiger-steps showed a significant increase in stance time and stride length compared with normal walking (p<.05), while both Tiger-steps shown significantly reduced cadence compared to normal walking (p<.05). Secondly, both Tiger-steps revealed significantly increased in hip and ankle joint range of motion compared with normal walking at all planes (p<.05). On the other hand, both Tiger-steps showed significantly increased knee joint range of motion compared with normal walking at the frontal and transverse planes (p<.05). Lastly, Gluteus maximus, biceps femoris, medial gastrocnemius, tibialis anterior of both tiger-step revealed significantly increased muscle activation compared with normal walking in gait cycle and stance phase (p<.05). On the other hand, in swing phase, the muscle activity of the vastus medialis, biceps femoris, tibialis anterior of both tiger-step significantly increased compared with those of normal walking (p <.05). Conclusion: As a result of this study, Tiger step revealed increased in 3d range of motion of lower extremity joints as well as the muscle activities associated with range of motion. These findings were evaluated as an increase in stride length, which is essential for efficient walking. Therefore, the finding of this study prove the effectiveness of the tiger step when walking uphill, and it is thought that it will help develop a more efficient tiger step in the future, which has not been scientifically proven.

• Journal of Marine Life Science
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• v.8 no.1
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• pp.87-92
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• 2023

Microplastic particles are ubiquitous in the environment and not standardized particles of size, shape, or type. Therefore, it is very limited to establish a risk assessment framework that accurately evaluated and manage the multi-dimension of marine environment including seawater and sediment based on toxic data. In the study, we review the characteristics and effects of marine environmental microplastic and suggest risk assessment framework (draft) based on the distribution and impact of marine environmental microplastics. Although, the characteristics of environmental microplastic are very widely but the most abundant toxic data are concentrated on unique shape and type, and there are also large gaps of test organism between laboratory-exposed organisms and resident species. Great limitations with respect to toxicity data quality also exist for traditional effect assessment methods, which in reliability of the resulting risk characterizations. However, considering the fact that the international community's movement on microplastics management is gradually strengthening and the pollution level of microplastics in marine environment is increasing, further research on environmental relevant risk assessment technique should be proposed based on the characteristics of microplastics in the marine environment.

• Korean Journal of Applied Biomechanics
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• v.33 no.3
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• pp.110-117
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• 2023

Objective: The purpose of this study was to find out kinematic and kinetic differences the lower extremity joint according to the landing type during vertical jump movement after jump landing, and to present an efficient landing method to reduce the incidence of injury in youth players. Method: Total of 24 Youth players under Korean Sport and Olympic Committee, who used either heel contact landing (HCG) or toe contact landing (TCG) participated in this study (HCG (12): CG height: 168.7 ± 9.7 cm, weight: 60.9 ± 11.6 kg, age: 14.1 ± 0.9 yrs., career: 4.3 ± 2.9 yrs., TCG height: 174.8 ± 4.9 cm, weight: 66.9 ± 9.9 kg, age 13.9 ± 0.8 yrs., career: 4.7 ± 2.0 yrs.). Participants were asked to perform jump landing consecutively followed by vertical jump. A 3-dimensional motion analysis with 19 infrared cameras and 2 force plates was performed in this study. To find out the significance between two landing styles independent t-test was performed and significance level was set at .05. Results: HCG showed a significantly higher dorsi flexion, extension and flexion angle at ankle, knee and hip joints, respectively compared with those of TCG (p<.05). Also, HCG revealed reduced RoM at ankle joint while it showed increased RoM at knee joint compared to TCG (p<.05). In addition, HGC showed greater peak force, a loading rate, and impulse than those of TCG (p<.05). Finally, greater planta flexion moment was revealed in TCG compared to HCG at ankle joint. For the knee joint HCG showed extension and flexion moment in E1 and E2, respectively, while TCG showed opposite results. Conclusion: Compared to toe contact landing, the heel contact landing is not expected to have an advantage in terms of absorbing and dispersing the impact of contact with the ground to the joint. If these movements continuously used, performance may deteriorate, including injuries, so it is believed that education on safe landing methods is needed for young athletes whose musculoskeletal growth is not fully mature.

• Journal of International Area Studies (JIAS)
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• v.15 no.1
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• pp.83-108
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• 2011

South America has vast energy resources with the renewable and non-renewable sources. However, many countries in the region are unable to guarantee adequate energy security both of energy supply and demand. Currently the possibility of energy security is high through regional energy integration based on the potential economic benefits. The difference of regulation system with the individual countries in the region impose strong barriers to integration process. Security of energy supply and its demand as well is fundamental issues in this region and regional energy cooperation is essential for getting rid of the insecurity of energy supplies. Despite of this problem, currently Latin American countries made a great effort to make multilateral energy security regime through projecting great energy infrastructure network(e.g. IIRSA) or mechanism especially in South America, which can give countries access to the region's reserve supplies by providing regulations and pricing mechanism with a shared energy market in this region. Brazil's active leading in the formulation of such movement toward energy security integration and participation of energy infrastructure network is good initiative to enforce this great energy security change. Politically and economically, Brazil's geographical position and the level of market size and oil and natural gas resources, in addition the leadership in renewable energy sources make it a sound candidate to take over the coordination of the secure integration of region's energy market. However, on the conditions of existing many obstacles such as, control of the output of the region's power plant, energy flows, the environmental matter within local community must be overcome to make more advance process and steps. Finally, to secure more institutional approach, this region must settle regional disputes resolution regime urgently.

• Journal of the Korean Geotechnical Society
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• v.26 no.5
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• pp.37-48
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• 2010

In this study, the seepage flow monitoring method by the hydraulic head loss rate was developed for the purpose of application to offshore construction site enclosed by cofferdams in which seepage force varies periodically. The amount of the hydraulic head loss rate newly defined in this graph was in a range between 0 and 1. The zero of the rate means the existence of flow with no seepage resistance. The 1 of the rate means no seepage flow through the ground. The closer to 1 the coefficient of determinant in the hydraulic head loss graph is, the more the ground through which seepage water flows is stable. The closer to 0 the coefficient of determinant in the hydraulic head loss graph is, the more the ground through which seepage water flows was unstable and the higher the possibilities of existence of empty space or of occurrence of piping on the seepage flow pass in the ground is. The hydraulic head loss graph makes it possible to monitor sensitively the situation of seepage flow state, and the graph helps to understand easily the seepage flow state at the specific section on the whole cofferdam.