• Journal for History of Mathematics
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• v.21 no.1
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• pp.79-96
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• 2008

In early 21st century, universities in Korea has been asked the new roles according to the changes of educational and social environment. With Korea's NURI and Brain Korea 21 project support, some chosen research oriented universities now should produce "teacher of teachers". We look 100 years back America's mathematics and see many resemblances between the status of US mathematics at that time and the current status of Korean mathematics, and find some answer for that. E. H. Moore had produced many good research mathematicians through his laboratory teaching techniques. R. L. Moore was his third PhD students. He developed his Texas/Moore method. In this article, we analyze what R. L. Moore had done through his American School of Topology and Moore method. We consider the meaning that early University of Texas case gives us in PBL(Problem Based Learning) process.

• Geomechanics and Engineering
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• v.13 no.5
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• pp.715-742
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• 2017

Earth berms are often left in place to support retaining walls or piles in order to eliminate horizontal struts in excavations of soft soil areas. However, if the excavation depth is relatively large, an earth berm-supported retaining system may not be applicable and could be replaced by a multi-bench retaining system. However, studies on multi-bench retaining systems are limited. The goal of this investigation is to study the deformation characteristics, internal forces and interaction mechanisms of the retaining structures in a multi-bench retaining system and the failure modes of this retaining system. Therefore, a series of model tests of a two-bench retaining system was designed and conducted, and corresponding finite difference simulations were developed to back-analyze the model tests and for further analysis. The tests and numerical results show that the distance between the two rows of retaining piles (bench width) and their embedded lengths can significantly influence the relative movement between the piles; this relative movement determines the horizontal stress distribution in the soil between the two rows of piles (i.e., the bench zone) and thus determines the bending moments in the retaining piles. As the bench width increases, the deformations and bending moments in the retaining piles decrease, while the excavation stability increases. If the second retaining piles are longer than a certain length, they will experience a larger bending moment than the first retaining piles and become the primary retaining structure. In addition, for varying bench widths, the slip surface formation differs, and the failure modes of two-bench retained excavations can be divided into three types: integrated failure, interactive failure and disconnected failure.

• Korean Journal of Logic
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• v.22 no.1
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• pp.1-23
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• 2019

Gott, Carter, Leslie, Bostrom and so on, as Descartes did, have made the evidence that is "I am here as an observer" to support many other beliefs. Bostrom and others who studied observation selection effects are missing two points. First, the self-consciousness information of the ones who just came up is distinct from that of the ones who have awoken. The awoken 'I' can trace back by memory to the past, but the 'I' who just came up can not. Second, when calculating credence, we must distinguish the ones in the possible worlds from the ones in the actual worlds. An estimate of credence where only one possible world is actualized among all possible worlds, differs fundamentally from that where all possible worlds are actualized. Keeping these two points in mind, we have explored what is the nature of the self-consciousness information of the one who just came up. We examine in depth the two human embryos thought experiment.

• Geomechanics and Engineering
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• v.19 no.2
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• pp.153-165
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• 2019

A case study of monitoring and analysis of surface settlement induced by tunneling of Tabriz metro line 2 (TML2) is presented in this paper. The TML2 single tunnel has been excavated using earth pressure balanced TBM with a cutting-wheel diameter of 9.49 m since 2015. Presented measurements of surface settlements, were collected during the construction of western part of the project (between west depot and S02 station) where the tunnel was being excavated in sand and silt, below the water table and at an average axis depth of about 16 m. Settlement readings were back-analyzed using Gaussian formula, both in longitudinal and transversal directions, in order to estimate volume loss and settlement trough width factor. In addition to settlements, face support and tail grouting pressures were monitored, providing a comprehensive description of the EPB performance. Using the gap model, volume loss prediction was carried out. Also, COB empirical method for determination of the face pressure was employed in order to compare with field monitored data. Likewise, FE simulation was used in various sections employing the code Simulia ABAQUS, to investigate the efficiency of numerical modelling for the estimating of the tunneling induced-surface settlements under such a geotechnical condition. In this regard, the main aspects of a mechanized excavation were simulated. For the studied sections, numerical simulation is not capable of reproducing the high values of in-situ-measured surface settlements, applying Mohr-Coulomb constitutive law for soil. Based on results, for the mentioned case study, the range of estimated volume loss mostly varies from 0.2% to 0.7%, having an average value of 0.45%.

• Safety and Health at Work
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• v.5 no.4
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• pp.203-209
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• 2014

Background: Coal mining is of significant economic importance to the Australian economy. Despite this fact, the related workforce is subjected to a number of psychosocial risks and musculoskeletal injury, and various psychological disorders are common among this population group. Because only limited research has been conducted in this population group, we sought to examine the relationship between physical (pain) and psychological (distress) factors, as well as the effects of various demographic, lifestyle, and fatigue indicators on this relationship. Methods: Coal miners (N = 231) participated in a survey of musculoskeletal pain and distress on-site during their work shifts. Participants also provided demographic information (job type, age, experience in the industry, and body mass index) and responded to questions about exercise and sleep quality (on-and off-shift) as well as physical and mental tiredness after work. Results: A total of 177 workers (80.5%) reported experiencing pain in at least one region of their body. The majority of the sample population (61.9%) was classified as having low-level distress, 28.4% had scores indicating mild to moderate distress, and 9.6% had scores indicating high levels of distress. Both number of pain regions and job type (being an operator) significantly predicted distress. Higher distress score was also associated with greater absenteeism in workers who reported lower back pain. In addition, perceived sleep quality during work periods partially mediated the relationship between pain and distress. Conclusion: The study findings support the existence of widespread musculoskeletal pain among the coal-mining workforce, and this pain is associated with increased psychological distress. Operators (truck drivers) and workers reporting poor sleep quality during work periods are most likely to report increased distress, which highlights the importance of supporting the mining workforce for sustained productivity.

• The Korean Journal of Pain
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• v.34 no.4
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• pp.394-404
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• 2021

Background: We aimed to investigate the effect of epidural polydeoxyribonucleotide (PDRN) on mechanical allodynia and motor dysfunction in a rat model of lumbar foraminal stenosis (LFS). Methods: This study was conducted in two stages, using male Sprague-Dawley rats. The rats were randomly divided into eight groups. In the first stage, the groups were as follows: vehicle (V), sham (S), and epidural PDRN at 5 (P5), 8 (P8), and 10 (P10) mg/kg; and in the second stage, they were as follows: intraperitoneal PDRN 8 mg/kg, epidural 3,7-dimethyl-1-propargilxanthine (DMPX) (0.1 mg/kg), and DMPX (0.1 mg/kg). The LFS model was established, except for the S group. After an epidural injection of the test solutions, von Frey and treadmill tests were conducted for 3 weeks. Subsequently, histopathologic examinations were conducted in the V, S, P5, and P10 groups. Results: A total of 65 rats were included. The P8 and P10 groups showed significant recovery from mechanical allodynia and motor dysfunction at all time points after drug administration compared to the V group. These effects were abolished by concomitant administration of DMPX. On histopathological examination, no epineurial inflammation or fibrosis was observed in the epidural PDRN groups. Conclusions: Epidural injection of PDRN significantly improves mechanical allodynia and motor dysfunction in a rat model of LFS, which is mediated by the spinal adenosine A_2A receptor. The present data support the need for further research to determine the role of epidural PDRN in spinal stenosis treatment.

• International Area Studies Review
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• v.16 no.1
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• pp.303-325
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• 2012

This paper is to provide an analysis on the European Globalisation Adjustment Fund(EGF) program and the study of European Member State. Established in December 2006, the EGF was originally intended to help workers who were affected by redundancies resulting from globalisation. The EGF at present also provides support to workers who were made redundant as a direct result of the global financial and economic crisis. In general, EGF measures are defined as assistance actions for job search, training, upskilling, outplacement, business start-up, etc. The paper focuses on the cases implemented by EGF for redundant workers harmed by globalisation and by a direct result of the global financial & economic crisis, and also focuses on the statistical portrait of the EGF 2007-2011. In addition, the paper provides criteria & implications of the EGF in the changing international economy. Finally, we could learn the importance of the EGF program through the analysis in this paper. With criteria & implications of the EGF program, the effective application to keep workers in employment or help them back into jobs would help us get over difficulties.

• Ocean and Polar Research
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• v.40 no.4
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• pp.259-270
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• 2018

The purpose of this study is to provide information to understand the context of the Antarctic Treaty System by looking back on its development process. It also aims to review the roles and activities of the CEP in the System in order to support the improvement of our Antarctic science policy. This study considered the developmental histories of independent conventions for Antarctic conservation and Protocol on Environmental Protection to the Antarctic Treaty under the system. CEP, established in accordance with the Protocol, has expanded its roles in the ATCM under the circumstances of climate change and increasing human activities in the treaty area. I examined CEP's functions, relationships with formal observers, and its activities along with CCRWP. In addition, I have estimated the contribution of the Parties to the CEP based on the documents submitted by the Parties. The leading Parties of the System have strengthened their initiatives to expand contributions to CEP with their output based on national Antarctic Program. However, Korea has not been able to take initiatives in the System even though Korea has invested considerable resources in its Antarctic program. To strengthen Korea's capability to instigate initiatives in the system, I suggest the following approaches: Firstly, Korea should improve its Antarctic science policy based on the newly established CEP five-year work plan; Secondly, Korea should organize a long-standing expert group to focus on Antarctic environmental policy and related scientific information; finally, Korea should intensify its collaboration with other Parties in developing Antarctic environmental priority issues.

• Korean Journal of Applied Biomechanics
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• v.29 no.2
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• pp.105-112
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• 2019

Objective: The main purpose of this study was to investigate the effects of wearing an ankle weight belt while performing gait in water by focusing on the effect of using ankle weights have on the gait kinematics and the muscle activities for developing optimum training strategies. Method: A total of 10 healthy male university students were recruited for the study. Each participant was instructed to perform 3 gait conditions; normal walking over ground, walking in water chest height, and walking in water chest height while using ankle weights. All walking conditions were set at control speed of $4km/h{\pm}0.05km/h$. The depth of the swimming pool was at 1.3 m, approximately chest height. The motion capture data was recorded using 6 digital cameras and the EMG was recorded using waterproof Mini Wave. From the motion capture data, the following variables were calculated for analysis; double and single support phase (s), swing phase (s), step length (%height), step rate (m/s), ankle, knee, and hip joint angles ($^{\circ}$). From the electromyography the %RVC of the lower limb muscles medial gastrocnemius, rectus femoris, erector spinae, semitendinosus, tibialis anterior, vastus lateralis oblique was calculated. Results: The results show significant differences between the gait time, and step length between the right and left leg. Additionally, the joint angular velocities and gait velocity were significantly affected by the water resistance. As expected, the use of the ankle weights increased all of the lower leg maximum muscle activities except for the lower back muscle. Conclusion: In conclusion, the ankle weights can be shown to stimulate more muscle activity during walking in chest height water and therefore, may be useful for rehabilitation purposes.

• Journal of Korean Clinical Nursing Research
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• v.26 no.3
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• pp.327-336
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• 2020

Purpose: The purpose of this study was to describe changes in positive psychological capital, organizational commitment and burnout according to work periods for new nurses. Methods: A longitudinal study was done using surveys of 91 nurses from a tertiary hospital located in Seoul, South Korea. Data were collected from these newly graduated nurses during the period from July 2018 to September 2019, three times (2 months, 4 months and 6 months after starting to work). Results: Hope of positive psychological capital decreased after 6 months of work (F=7.11, p=.001) and organizational commitment decreased after 4 months of work (F=15.30, p<.001). Factors influencing participants' burnout included the optimism of positive psychological capital and continuance of organizational commitment. These factors explained 51.3% of the variance in burnout (F=48.47, p<.001). Conclusion: Organizational support for new nurses is urgently needed. It is necessary to develop programs to strengthen the positive psychological capital of newly graduated nurses to reduce their burnout and to help their job adaptation.