• Journal of the Earthquake Engineering Society of Korea
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• v.9 no.3 s.43
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• pp.1-8
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• 2005

This paper describes a new objective methodology of seismic building damage assessment which is called Advanced Component Method(ACM). ACM is a major attempt to replace the conventional loss estimation procedure, which is based on subjective measures and the opinions of experts, with one that objectively measures both earthquake intensity and the response ol buildings. First, response of typical buildings is obtained analytically by nonlinear seismic static analysis, push-over analyses. The spectral displacement Is used as a measure of earthquake intensity in order to use Capacity Spectrum Method and the damage functions for each building component, both structural and non-structural, are developed as a function of component deformation. Examples of components Include columns, beams, floors, partitions, glazing, etc. A repair/replacement cost model is developed that maps the physical damage to monetary damage for each component. Finally, building response, component damage functions, and cost model were combined probabilistically, using Wonte Carlo simulation techniques, to develop the final damage functions for each building type. Uncertainties in building response resulting from variability in material properties and load assumptions were incorporated in the Latin Hypercube sampling technique. The paper also presents and compares ACM and conventional building loss estimation based on historical damage data and reported loss data.

• International Journal of Highway Engineering
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• v.15 no.2
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• pp.19-27
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• 2013

PURPOSES : This study aims to investigate the snow-melt effects of an underground electric heater's snow-melt system via a field performance test, for evaluating the suitability of the system for use on a concrete pavement. The study also investigates the effectiveness of dynamic measures for clearing snow after snowfall events. METHODS : In order to check the field applicability, in November 2010, specimens were prepared from materials used for constructing concrete pavements, and underground electric heating meshes (HOT-mesh) were buried at depths of 50 mm and 100 mm at the site of the Incheon International Airport Construction Research Institute. Further, an automatic heating control system, including a motion sensor and pavement-temperature-controlled sensor, were installed at the site; the former sensor was intended for determining snow-melt effects of the heating control system for different snowfall intensities. Pavement snow-melt effects on snowy days from December 2010 to January 2011 were examined by managing the electric heating meshes and the heating control system. In addition, data on pavement temperature changes resulting from the use of the heating meshes and heating control system and on the dependence of the correlation between the outdoor air temperature and the time taken for the required temperature rise on the depth of the heating meshes were collected and analyzed. RESULTS : The effects of the heating control system's preheat temperature and the hot meshes buried at depths of 50 mm and 100 mm on the melting of snow for snowfalls of different intensities have been verified. From the study of the time taken for the specimen's surface temperature to increase from the preheat temperature ($0^{\circ}C$) to the reference temperature ($5{\sim}8^{\circ}C$) for different snowfall intensities, the correlation between the burial depth and outdoor air temperature has been determined to be as follows: Time=15.10+1.141Depth-6.465Temp CONCLUSIONS : The following measures are suggested. For the effective use of the electric heating mesh, it should be located under a slab it may be put to practical use by positioning it under a slab. From the management aspect, the heating control system should be adjusted according to weather conditions, that is, the snowfall intensity.

• Journal of the Korean Society of Propulsion Engineers
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• v.18 no.1
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• pp.73-84
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• 2014

The present paper includes recent research works on the estimation of physical properties like equivalence ratio and heat release rate of flame through chemiluminescence measurement. Modern combustion devices require a precise control to increase combustion stability as well as to suppress pollutant emissions. The determination of combustion characteristics from chemiluminescence provides practical advantages over other techniques. However, the technique is dependent on equivalence ratio, combustion pressure, inlet temperature, turbulent intensity and fuel type. The intensity ratio of $OH^*$ and $CH^*$ has a strong relation with an equivalence ratio for methane/air premixed flames. The global measurement of chemiluminescence is accepted as a good indicator for a global heat release rate.

• Journal of Acupuncture Research
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• v.33 no.2
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• pp.77-87
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• 2016

Objectives : This is a pilot study for a large randomized controlled trial to investigate the efficacy and safety of a newly developed contrast therapy device-- alternating topical heat and cold -- for patients with chronic low back pain. The main objective of this study is to confirm the feasibility of the study design. Methods : The design was a randomized, 2-arm, parallel-group, single-blind, placebo controlled trial. Patients in each group received real or sham contrast therapy in an acupuncture point 10 times over four weeks. The primary outcome measure was pain intensity on a 100-mm visual analogue scale (VAS). The secondary outcomes were back-related dysfunction based on the Oswestry Disability Index (ODI), the Roland-Morris disability questionnaire (RMDQ), and range of motion of lumbar spine based on the modified Schober test (mSchober test), Finger-to-Floor distance (FTF distance), and Finger-to-Thigh distraction (FTT distraction). Results : A total of 30 subjects with chronic low back pain were randomly assigned to a contrast therapy group (n＝15) or a sham group (n＝15). A repeated-measures analysis of variance showed statistically significant group time interaction for VAS, RMDQ, mSchober test and FTF distance (p<0.05). The treatment group showed significant improvement in pain intensity and functional disability as compared to the sham group. Conclusion : Contrast therapy may be an effective and safe treatment for chronic low back pain.

• Horticultural Science & Technology
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• v.16 no.3
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• pp.364-365
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• 1998

The present study was conducted to develop a more accurate and efficient measure than any other quantifying measures of the leaf variegation when influenced by changes in certain physical and environmental factors. Through this computer quantification for two Tradescantia cultivars, it was ascertained that total leaf area decreased and extent of the leaf variegation increased as light intensity increased. According to this result to determine the brightness of the leaf, using the same aforementioned measurement, the leaf color was brightest in the sun and it become darker as light intensity decreased. High correlation was found between total leaf and leaf variegation area measured by leaf area meter and the pixel of computer graphic file through scanning. Thus, the leaf area and leaf variegation area measurement using computer graphic will be used very efficiently.

• The Korean Journal of Pain
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• v.13 no.2
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• pp.175-181
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• 2000

Background: Pain is often measured using psychophysical scaling techniques. However, all of these methods found their limits, since they were based on the subjective sensations reported by the subjects. It is, therefore, desirable to validate psychophysical pain measures by simultaneously measuring some physiological correlate of nociception. We studied an objective method for measuring pain in human volunteer using R(III) nociceptive flexion reflex. Methods: Four different intensity of electrical stimuli between perception and 1.4 times the R(III) nociceptive flexion threshold were delivered to the sole of the feet in 8 normal volunteers. We measured the flexion reflex activity in the skin over the ipsilateral tibialis anterior muscle and subjects rated each stimulus on a visual analog scale (VAS) Results: Both R(III) nociceptive flexion reflex activity and VAS ratings showed a linear relationship with stimulus intensity and with each other in all volunteers. Conclusions: R(III) nociceptive flexion reflex elicited through electrical stimulation may used as an objective pain measurement, previsionary based on our study paradigm.

• Journal of Environmental Health Sciences
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• v.26 no.3
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• pp.32-37
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• 2000

Nowadays, a new word called SBS(sick building syndrome) has been come into existence. At the point of time when an interest about indoor air pollution and, according to this, countermeasure plan are internationally. Moreover institutional countermeasure should be attended at national level since indoor air quality in public places where many people gather is directly connected with national health. Especially indoor pollution of indoor stadia where all sorts of sports are held can give rise to every kinds of respiratory ailments to players as well as audiences. So it is presented as a main factor that indoor space of stadia is crowded with players and audiences compared with other kinds of indoor space. Therefore, in this research to analyze pollution degree of indoor circumstance for gymnasium and exercising room of folk wrestling. basketball, judo, wrestling, hapkido, swordsmanship and boxing making indoor gymnasium and exercising room an object, when 7 items were measures such as thermocircumstance(temperature, relative humidity, air current, intensity of illumination), dust, carbon monoxide, and carbon dioxide being based on the indoor environmental standard of the first clause of Article 45 of public utilization service which is showed at public hygiene of the Ministry of Health and Social Affairs, it was showed that indoor temperature, relative humidity, air current and intensity of illumination were over standard amount at the most of folk wrestling gymnasium and exercising room. Indoor density of carbon monoxide was preserved to the extent of standard amount (10ppm) at all gymnasiums but carbon dioxide was not in excess of standard amount(1,000 ppm) at most of gymnasiums. Indoor density of dust induced from respiration exceeded the standard amount (150 $\mu\textrm{g}$/㎥) at all gymnasiums of the folk wrestling. Since the folk wrestling players and participants feel physical subjective symptom seriously, in other words the degree of indoor air pollution at gymnasiums and exercising rooms of the folk wrestling is very high, fundamental solution and countermeasure plan should be presented.

• Journal of Environmental Science International
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• v.25 no.7
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• pp.1007-1016
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• 2016

Environmental policy implementation has been strengthened to protect the source waters in Korea and to improve their water quality. Increasing of non-point source caused water quality problem continuously. Research on runoff from forests, which occupy over 65% of the land in korea, is insufficient, and studies on the characteristics and influences of storm runoff are necessary. In this study, we chose to compare the effects of land use in the form of two types of forest distribution and then gathered data on storm characteristics and runoff properties during rainfall events in these areas. Furthermore, the significance and influences of the discharges were analyzed through correlation analysis, and multilateral runoff characteristics were examined by deducing a formula through $COD_{Mn}$ and TOC regression analysis. At two forest points, for which the basin areas differed from each other, flow changed according to storm quantity and intensity. The peak discharge at point A, where the basin area was big, was high, whereas water-quality fundamental items (BOD, $COD_{Mn}$, and SS) and TOC density were high at point B where the slope and storm intensity were high. Effects of dissolved organic matter were determined through correlation analysis, and the regression formulas for $COD_{Mn}$ and TOC were deduced by regression analysis. It is expected that the data from this study could be useful as basic information in establishing forest management measures.

• Journal of the Earthquake Engineering Society of Korea
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• v.7 no.6
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• pp.35-47
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• 2003

Seismic ground motion can vary significantly over distances comparable to the length of a majority of highway bridges on multiple supports. This paper presents results of fragility analysis of two actual highway bridges under ground motion with spatial variation. Ground motion time histories are artificially generated with different amplitudes, phases, as well as frequency contents at different support locations. Monte Carlo simulation is performed to study dynamic responses of the bridges under these ground motions. The effect of spatial variation on the seismic response is systematically examined and the resulting fragility curves are compared with those under identical support ground motion. This study shows that ductility demands for the bridge columns can be underestimated if the bridge is analyzed using identical support ground motions rather than differential support ground motions. Fragility curves are developed as functions of different measures of ground motion intensity including peak ground acceleration(PGA), peak ground velocity(PGV), spectral acceleration(SA), spectral velocity(SV) and spectral intensity(SI). This study represents a first attempt to develop fragility curves under spatially varying ground motion and provides information useful for improvement of the current seismic design codes so as to account for the effects of spatial variation in the seismic design of long-span bridges.

• Architectural research
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• v.20 no.1
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• pp.17-25
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• 2018

Countermeasures against earthquake disasters such as the seismic capacity evaluation and/or retrofit schemes of buildings, especially existing low-rise reinforced concrete buildings, have not been fully performed since Korea had not experienced many destructive earthquakes in the past. However, due to more than 1200 earthquakes with low or moderate intensity in the off-coastal and inland of Korea during the past 20 years, and due to the recent moderate earthquakes in Korea, such as the 2016 Gyeongju Earthquake with M=5.8 and the 2017 Pohang Earthquake with M=5.4, the importance of the future earthquake preparedness measures is highly recognized in Korea. The main objective of this study is to provide the basic information regarding seismic capacities of existing low-rise reinforced concrete buildings in Korea. In this paper, seismic capacities of 14 existing low-rise reinforced concrete public buildings in Korea are evaluated based on the Japanese Standard for Evaluation of Seismic Capacity of Existing Reinforced Concrete Buildings. Seismic capacities between existing buildings in Korea and those in Japan is compared, and the relationship of seismic vulnerability of Korean buildings and Japanese buildings damaged due to severe earthquakes are also discussed. Results indicated that Korean existing low-rise reinforced concrete buildings have a narrow distribution of seismic capacities and they are relatively lower than Japanese buildings, and are also expected to have severe damage under the earthquake intensity level experienced in Japan. It should be noted from the research results that the high ductility in Korean existing low-rise buildings obtained from the Japanese Standard may be overestimated, because most buildings investigated herein have the hoop spacing wider than 30 cm. In the future, the modification of strength and ductility indices in the Japanese Standard to propose the seismic capacity evaluation method of Korean buildings is most needed.