• Earthquakes and Structures
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• v.22 no.3
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• pp.305-318
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• 2022

This paper presents a comparative study of the damage potentials for the 2016 Gyeongju and 2017 Pohang earthquakes in Korea. Plausible technical explanations are provided for the more severe damage observed in the 2017 Pohang earthquake in spite of its relatively weaker magnitude and intensity measures based on the response analysis of elastic and inelastic single-degree-of-freedom systems for the recorded ground motions. In addition, a detailed case study was conducted for a fatally damaged piloti building with an eccentric shear wall core based on nonlinear dynamic analysis using the input ground motions modified for the building site.

• Annals of Occupational and Environmental Medicine
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• v.35
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• pp.49.1-49.7
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• 2023

The Korean Working Conditions Survey (KWCS) is a state-approved statistical survey that has been conducted by the Occupational Safety and Health Research Institute (OSHRI) every 3 years since 2006 to monitor changes in the working conditions of Koreans. This cross-sectional national survey involves a sample of 50,000 employed people aged 15 or older. KWCS measures various working conditions through > 130 survey questions, including questions regarding working hours, labor intensity, work-life balance, degree of exposure to risk factors, and subjective health status. Professional survey interviewers visit households and conduct face to face interviews. KWCS provides data and statistics for occupational safety and health polices and research in Korea. Furthermore, OSHRI holds academic conferences every year, awards high-quality academic papers, and supports researchers using data. Microdata is publicly available through the OSHRI website (https://oshri.kosha.or.kr).

• 한국체육학회지인문사회과학편
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• v.54 no.1
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• pp.553-566
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• 2015

This study was performed to identify the effects of different intensities of regular aerobic exercise on erythropoietin (EPO) and BDNF levels, and cognitive function and working memory in middle-aged women. Women aged 40 to 60 years residing in G-gu, Y-si, Gyeonggi-do were divided into 3 groups: control group, moderate-intensity aerobic exercise group and high-intensity aerobic exercise. All groups were asked to exercise at the given intensities, twice a week for a total of 12 weeks. Blood samples were collected from participants on week 0 (before exercising), week 6 and week 12, and then cognitive function and working memory tests were followed to measure erythropoietin (EPO) and BDNF levels, cognitive function and working memory. Repeated measures ANOVA, univariate analysis and follow-up test were performed on all data to compare the group, period and interaction through a SPSS. As a result, a significant difference over time was observed in EPO, BDNF, cognitive function and working memory; therefore, a follow-up one-way ANOVA analysis was performed on each group. As a result of analysis, a significant increase in erythrocyte, hematocrit, BDNF level and working memory was observed in moderate-intensity aerobic exercise group while erythrocyte and working memory were significantly increased inhigh-intensity aerobic exercise group. When comparing the results between the groups, the level of hematocrit was shown to be significantly higher in both moderate-and high-intensity aerobic group than the control group and also the higher level of hemoglobin was observed in both moderate-and high-intensity aerobic group comparing to control group. Considering the results of this study, therefore, a 12-week long aerobic exercise at moderate to high intensity positively affected EPO and BDNF levels, cognitive function and working memory in middle-aged women.

• Journal of Technology Innovation
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• v.24 no.4
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• pp.127-158
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• 2016

Multinational corporations' overseas R&D activities bring host countries positive effects such as knowledge spillover, technology transfer, job creation and etc. For this reason, many countries have made efforts to attract foreign firms' R&D investment in their national territories. Korean government have also implemented some policy measures to expedite foreign firms operating in Korea to increase R&D activities. However, the firms' R&D investment in Korea has still been unsatisfactory, and only few studies have examined this issue. Therefore, this study attempts to explain the R&D investment of foreign firms operating in Kore, from the perspective Dunning's eclectic paradigm. Utilizing linear regression and Tobit model, this study analyzes the influence of OLI advantages on R&D intensity of foreign firms in Korea. The result shows that locational advantages of Korea (such as revealed technological advantage) had positive influences on foreign firms' R&D intensity. However, the influence of other OLI advantages were different by foreign firms' nationalities. For instance, internalization advantages had influences on R&D intensity, but the directions were different between Japanese and other nationalities. Based on the results, we provided some discussion and attempted to draw implications for Korean government's FDI and R&D policy.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.6
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• pp.2617-2624
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• 2012

Interferential currents (IFC) and transcutaneous electrical nerve stimulation (TENS) are used for pain management. This study compared the analgesic effects of IFC and TENS on experimentally induced ischemic pain in otherwise pain-free subjects using a modified version of the submaximal-effort tourniquet technique. The subjects were 14 volunteers (7 male, 7 female) without known pathology that could cause pain. Their mean age was $26.7{\pm}2.0$ years. A single-blind, sham controlled, parallel-group method was used. The primary outcome measure was the change in the self-report of pain intensity during 1 of 3 possible interventions: (1) IFC, (2) TENS, or (3) sham electrotherapy. The IFC and TENS were administered on the forearm, and the sham electrotherapy group received no current output via a dummy stimulator. The results show that a 2-way repeated-measures analysis of variance revealed that there was no change in pain intensity during treatment when all 3 groups were considered together. The mean to pain intensity with the IFC intervention was no different than with TENS. Thus, Statistical analysis showed that both interventions decreased the pain intensity ratings significantly and the difference between interventions was not simply insignificant. IFC has been shown to be more comfortable than TENS in present studies and is likely to be better accepted and tolerated by patients, clinical investigation is warranted.

• Journal of Korean Society of Forest Science
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• v.101 no.1
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• pp.28-35
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• 2012

Rainfall is widely recognized as a major landslide-triggering factor. Most of the latest landslides that occurred in South Korea were caused by short-duration heavy rainfall. However, the relationship between rainfall characteristics and landslide occurrence is poorly understood. To examine the effect of rainfall on landslide occurrence, cumulative rainfall(mm) and rainfall intensity(mm/hr) of serial rain and antecedent rainfall(mm) were analyzed for 18 landslide events that occurred in the southern and central regions of South Korea in June and July 2011. It was found that all of these landslides occurred by heavy rainfall for one or three days, with the rainfall intensity exceeding 30 mm/hr or with a cumulative rainfall of 200 mm. These plotted data are beyond the landslide warning criteria of Korea Forest Service and the critical line of landslide occurrence for Gyeongnam Province. It was also found that the time to landslide occurrence after rainfall start(T) was shortened with the increasing average rainfall intensity(ARI), showing an exponential-decay curve, and this relation can be expressed as "T = $94.569{\cdot}exp$($-0.068{\cdot}ARI$)($R^2$=0.64, p<0.001)". The findings in this study may provide important evidences for the landslide forecasting guidance service of Korea Forest Service as well as essential data for the establishment of non-structural measures such as a warning and evacuation system in the face of sediment disasters.

• Journal of Ocean Engineering and Technology
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• v.33 no.6
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• pp.590-596
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• 2019

Numerous deaths and substantial property damage have occurred recently due to frequent disasters of the highest intensity according to the abnormal climate, which is caused by various problems, such as global warming, all over the world. Such large-scale disasters have become an international issue and have made people aware of the disasters so they can implement disaster-prevention measures. Extensive information on disaster prevention actively has been announced publicly to support the natural disaster reduction measures throughout the world. In Japan, diverse developmental studies on disaster prevention systems, which support hazard map development and flood control activity, have been conducted vigorously to estimate external forces according to design frequencies as well as expected maximum frequencies from a variety of areas, such as rivers, coasts, and ports based on broad disaster prevention data obtained from several huge disasters. However, the current reduction measures alone are not sufficiently effective due to the change of the paradigms of the current disasters. Therefore, in order to obtain the synergy effect of reduction measures, a study of the establishment of an integrated system is required to improve the various disaster prevention technologies and the current disaster prevention system. In order to develop a similar typhoon search system and establish a disaster prevention infrastructure, in this study, techniques will be developed that can be used to forecast typhoons before they strike by using artificial intelligence (AI) technology and offer primary disaster prevention information according to the direction of the typhoon. The main function of this model is to predict the most similar typhoon among the existing typhoons by utilizing the major typhoon information, such as course, central pressure, and speed, before the typhoon directly impacts South Korea. This model is equipped with a combination of AI and DNN forecasts of typhoons that change from moment to moment in order to efficiently forecast a current typhoon based on similar typhoons in the past. Thus, the result of a similar typhoon search showed that the quality of prediction was higher with the grid size of one degree rather than two degrees in latitude and longitude.

• Journal of Korean Society of Rural Planning
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• v.26 no.4
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• pp.81-91
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• 2020

This study was conducted to analyse climate change impact on agriculture infrastructure and propose improved measures on vulnerable areas. Recently, Climate change has resulted in damaging effects on agricultural fields through increases in drought intensity and flood risk. It is expected that this impact will increase over time. This study shows that Gyeong-gi and Chung-nam provinces are affected by drought and Gyeong-buk and Gyeong-nam provinces are affected by heavy rain. However, there are also regional variations within each province. Agricultural infrastructure affected by drought may also be affected by heavy rain. Increased damages on the infrastructure due to increased extreme weather events require preventive measures especially in vulnerable areas. In order to minimize the damage by climate change, we need to introduce a reform in the system which selects project region by analysing climate change impacts. Furthermore, impact assessment of climate change from projects such as 'water supply diversification', 'flooded farmland improvement', and 'irrigation facility reinforcement' also need to be adopted to improve the measures. The results of this study are expected to provide a foundation for establishing measures on coping with climate change in the agricultural sector.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.10
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• pp.3802-3807
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• 2010

In most sports, a key evaluator of athletic performance is sprinting speed. There are two trainable factors associated with speed including mechanical efficiency and force production. The squat exercise is one of the beneficial exercises implemented to enhance lower extremity power for sprinters. However, there has been little research on the optimal exercise intensity for sprinting performance. This study was to investigate whether performing different squat exercises prior to a 40m sprint would improve running speed. Ten male high school sprinters performed six 40m sprints following the different squat intensities (30%, 50%, 70%, and 90% of 1RM). A one-way ANOVA with repeated measures revealed that 40m sprint times had significantly improved after 50% ($5.27{\pm}0.13$, p<0.0001) and 70% ($5.26{\pm}0.15$, p<0.0001) of 1RM squat exercises compared to sprint times not following a squat % ($5.33{\pm}0.16$). Performing squat exercises with intensities of 50% and 70% of 1RM may improve 40m sprint times. Therefore, it is suggested that coaches and sprinters could include a medium intensity squat exercise (70%) in the warm-up procedure in order to improve sprint performance.

• Journal of Korean Ophthalmic Optics Society
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• v.6 no.2
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• pp.71-75
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• 2001

In this paper, a three-dimensional measuring system of thermoluminescence(TL) spectra based on temperature, wavelength and luminescence intensity was introduced. The system was composed of a spectrometer, temperature control unit for thermal stimulation, photon detector and personal computer for control the entire system. Temperature control was achieved by using feedback to ensure a linear-rise in the sample temperature. Digital multimeter(KEITHLEY 195A) measures the electromotive force of Copper-Constantan thermocouple and then transmits the data to the computer through GPIB card. The computer converts this signal to temperature using electromotive force-temperature table in program, and then control the power supply through the D/A converter. The spectrometer(SPEX 1681) is controlled by CD-2A, which is controlled by the computer through RS-232 communication port. For measuring the luminescence intensity during the heating run, the electrometer(KEITHLEY 617) measures the anode current of photomultiplier tube(HAMAMATSU R928) and transmits the data to computer through the A/D converter. And, we measured and analyzed thermoluminescence of $CaSO_4$ : Dy, P using the system. The measuring range of thermoluminescence spectra was 300K-575K and 300~800 nm, $CaSO_4$ : Dy. P was fabricated by the Yamashita's method in Korea Atomic Energy Research Institute(KAERI) for radiation dosimeter. Thermoluminesce spectra of the $CaSO_4$ : Dy, P consist of two main peak at temperature of $205^{\circ}C$, wavelength 476 nm and 572 nm and with minor ones at 658 nm and 749 nm.