• Journal of Bio-Environment Control
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• v.26 no.1
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• pp.27-34
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• 2017

This study was carried out to estimate structural stabilities in respect of ground footings of plastic greenhouses on reclaimed lands. A 6m-wide multi-span plastic greenhouse with steel spiral piles as well as two 8.2m-wide single-span greenhouses with steel spiral piles and continuous pipe foundation respectively were built up on a reclaimed land with a SPT N-Value of 2 and measured how much the greenhouses were lifted up and subsided. In addition, the uplift capacity of three kinds of spiral piles(${\phi}50$, ${\phi}75$ and ${\phi}100$) was determined on a nearby reclaimed land. The results showed that the greenhouses with spiral piles had a slight vertical displacement like moving up and down but the scales of the rising up and sinking were negligible when compared to that of the greenhouses. The vertical displacement of the multi-span greenhouse ranged from +9.0mm(uplift) to -11.5mm(subsidence). As for the single-span greenhouses with spiral piles and continuous pipe foundation, the measurements showed that it varied from +1.3mm to -7.7mm and from +0.9mm to -11.2mm, respectively. The allowable uplift capacity of spiral piles could all be determined under criteria of ultimate load and accordingly had a value of 0.40kN, 1.0kN and 2.5kN, respectively. It was not entirely certain enough to make a final judgement on structural stabilities in respect of ground footings, it appeared likely however that the greenhouses with steel spiral piles was tentatively observed without any problems on reclaimed lands within the period.

• Journal of Oriental Neuropsychiatry
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• v.21 no.2
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• pp.157-169
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• 2010

Objectives : The aim of this study was to investigate the characteristics of Hwa-Byung(HB) patients, draw the clinical key issue of HB, and provide the data as the basis for development of Clinical Guideline of HB. Methods : The study participants included 151 subjects who thought they have HB in 9 site. For all patients, we used HB epidemiologic study protocol, which include the Korean version of the Structured Clinical Interview for the DSM-IV Diagnosis (SCID-1), diagnostic criteria of HB, symptoms check list, pattern identification tool, psychiastric psychological questionaires, and Framingham coronary risk score(FRS). Results : 1. For all participants, 62 % of subjects were diagnosed with HB. These patients had comorbid DSM-IV diagnoses with depression (65%) and anxiety (27%). But 22% of these patients had only HB. 2. HB patients had various physical symptoms when visiting, were diagnosed as various disease, and undergone medical treatments in the past. Among the diagonsed illness, Gastronitestinal diseases (51.6%), psychiatric disorders(40.9%), endocrine diseases(39.8%) were being the most frequent. The frequent physical symptoms of HB patients reported were chest discomfort, head ache, pallpitation, frequent sigh, amnesia, shoulder pain, dry mouth, eye fatigue etc. 3. HB patients had high scores in psychologic questionares, CES-D, STAI, and STAXI. It means that HB patients might be low-level emotional stability. 4. Participant had negative opinion about the treatment of HB that it would be difficult or impossible (65.7%), but they neglect the need of medical treatment. Conclusions : This result shows that HB is comorbid with various psychiatric disease, but it has different physio-psychological symptoms from others and there were only HB patients. so we identify HB is independent disease. Moreover, there were the wrong perception of HB which blocking treatments. These problems support that the neccesity of development of Clinical Guideline of HB.

• Fire Science and Engineering
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• v.34 no.1
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• pp.47-54
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• 2020

This paper proposes a solution to the problems of constructing and installing sway braces for existing standpipes in narrow spaces and pits. The study develops a floor-fixed sway brace for a narrow space that can support the ground area under horizontal seismic loads (X-axis, Y-axis) as well as vertical seismic loads (Z-axis). The results of structural analysis using SolidWorks simulation showed that the eccentric load was generated in the first design according to the anchored position along the vertical direction, and the problem of exceeding the allowable stress of the material along the horizontal and vertical directions. In the second design model, deformation caused by the eccentric load along the vertical direction, similar to the first design model, did not occur. The maximum strain rate was 0.17%, which is approximately 12.84% less than the first design model (Maximum strain rate of 13.01%). It was confirmed that the structural stability and durability improved. Compressive and tensile load testing of the prototypes showed that all of them meet the performance criteria of the standard.

• The Journal of Engineering Geology
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• v.30 no.1
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• pp.43-57
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• 2020

The objective of this study was to evaluate the performance of high-strength lattice girders as a possible superior alternative to conventional steel arch ribs. For this purpose, the structural characteristics of supports were analyzed using numerical analysis, and their performance was evaluated using maximum bending load tests and tensile tests of the welded joint. According to the results of structural analysis, the optimum size of the upper and lower members and plates is 50 mm × 31.8 mm × 25.4 mm, demonstrating excellent functionality and economic efficiency. High-strength lattice girders of dimensions 55 mm × 30 mm × 20 mm and 85 mm × 30 mm × 20 mm, determined from bending load tests, are found to meet both the reference values and the target values of H-profiles 100 and 125. A review of the ratio of theoretical deflection to actual deflection shows that the high-strength lattice girder developed during this study meets fewer than five of the evaluation criteria for lattice girder deflections proposed by the Federal Railway Department of Germany. Finally, tensile test results reveal that the welded joint of the high-strength lattice girder at the main steel bar-auxiliary steel bar-plate junction exceeds the target value, indicating that the welded joint has sufficient stability.

• Tunnel and Underground Space
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• v.27 no.1
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• pp.39-49
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• 2017

The factor of safety (FOS) is commonly used as an index to quantitatively state the degree of safety of various rock structures. Therefore it is important to understand the definition and characteristics of the adopted FOS because the calculated FOS may be different according to the definition of FOS even if it is estimated under the same stress condition. In this study, four local factors of safety based on maximum shear stress, maximum shear strength, stress invariants, and maximum principal stress were defined using the Mohr-Coulomb and Hoek-Brown failure criteria. Then, the variation characteristics of each FOS along five stress paths were investigated. It is shown that the local FOS based on the shear strength, which is widely used in the stability analysis of rock structures, results in a higher FOS value than those based on the maximum principal stress and the stress invariants. This result implies that the local FOS based on the maximum shear stress or the stress invariants is more necessary than the local FOS based on the shear strength when the conservative rock mechanics design is required. In addition, it is shown that the maximum principal stresses at failure may reveal a large difference depending on the stress path.

• Journal of Food Hygiene and Safety
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• v.13 no.1
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• pp.24-28
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• 1998

Korean sesame oil mixed with corn oil and Chinese sesame oil were subjected to instrumental determination for fatty acid composition, sesaminol and sesamin contents, and induction period by AOM test to obtain basic data for ascertaining the truth of pure sesame oil, respectively. In sesame oil mixed with corn oil, stearic acid content of sesame oil containing above 20% corn oil was remarkably discriminated from that of pure sesame oil. Oleic and linoleic acid contents of sesame oil with 10% corn oil were significantly differnt from that of pure sesame oil. Stearicllinoleic acid ratio of sesame oil mixed with corn oil dcreased in proportion to corn oil content in sesame oil. Sesamolin and sesamin contents of sesame oil containing 30% corn oil were lower 18.3% and 21.0% than those of pure sesame oil, respectively. Induction periods of sesame oil by AOM were 8.14~9.24 hrs in Chinese sesame oil and sesame oils including 20% and 40% corn oils, but around 16hrs in Korean pure sesame oil. Based on the above results, it is considered that the comparisons of fatty acids, sesaminol and sesamin contents, and induction period by AOM test might be one of the potential criteria in discriminating between pure sesame oil and sesame oil mixed with corn oil.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.6
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• pp.1101-1107
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• 2016

As an increase in the amount of RAP, there are growing interests in recycling asphalt concrete. In case of using the RAP as recycled asphalt pavement, it tends to be quality deteriorate. Therefore, the amount of RAP using is advised to be limited or has to be used with rejuvenator. In this study, asphalt mixture containing WMRA was analyzed to be used up to 50% for the sake of convenience on the process. As the results of evaluation, there was no significant difference in case of using 30% of RAP in the test of Marshall stability. However, in case of WMRA using up to 50%, it was satisfied criteria by flow value at 34.7. Further, result of toughness test was found that the crack resistance showed 55% higher than using straight asphalt when using WMRA binder up to 50%. According to the results of directly comparing crack resistance through repeated direct tensile test, it was shown that the fatigue crack resistance of WMRA pavement was increased by 263%. Therefore, it was shown that WMRA binder was effective in recycling RAP because WMRA binder could increase the percentage of RAP using up to 50%.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.567-573
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• 2020

This study was done to develop indicators for cities that can be used in the long term and in a sustainable manner. Activation indicators were developed to improve the resilience in the downtown area of Seo-gu, Incheon. Preliminary indicators were derived from prior studies on similar indicators of resilience for urban regeneration, and an expert opinion survey was conducted to analyze the suitability and importance of the indicators. Activation indicators were established for improving urban resilience in six areas: population stability, social inclusion, industrial diversity, local productivity, environmental sustainability, and social-based convenience. From 60 preliminary indicators, 42 indicators were selected through the expert opinion surveys for securing an economically active population, establishing a living infrastructure, improving the settlement environment, and upgrading industry to reflect the characteristics of the West, including industrial complexes. It was found that diversification is necessary. Further study is still necessary to improve the objectivity of the indicators and calculate a resilience index. The significance of this study is that it looks at quantitative indicators, complements other studies on regional decline diagnosis, and presents realistic alternatives suitable for domestic situations based on the concept of resilience.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.4
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• pp.248-258
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• 2020

In this study, an empirical analysis was performed with regards to traditional markets in Seoul, South Korea to find which physical maintenance elements, such as facility improvement for successful urban restoration, have greater effects on the expectation and activation awareness of successful urban restoration. This study targeted traditional markets located at the center of Seoul, which are visited by many domestic and international tourists as well as general consumers and are revitalizing the downtown area. A survey was conducted to collect a total of 515 completed questionnaires. Data analysis was performed using SPSS 23.0 and AMOS 22.0. The results of the analyses in this study indicate relevant urban invigoration factors (psychological, physical, diversity, functional, and stability factors), and it was observed that the expectation of urban regeneration was under the direct influence of the invigoration factors. Such a finding is meaningful in that it suggests a set of criteria to evaluate the concept of traditional markets in a comprehensive manner for successful urban regeneration while highlighting relevant invigoration factors for traditional marketplaces for the purpose of urban regeneration.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.17-24
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• 2020

This study examined the spectral information and reflectance of cracks of an embankment with drone-based hyperspectral imagery for crack detection. A Nano-Hyperspec mounted on a drone was used as a sensor, and hyperspectral videos of different intensities of illumination of the cracks on the embankment located in the downstream of Andong-Dam were obtained. An analysis of the data value of the illumination and peak data-value, the coefficients of determination were calculated to be 0.9864 of the uncracked areas and 0.9851 of the cracked area. The reflectance of each area showed a similar value and pattern, regardless of the intensity of illumination. This result may have occurred because the reference values of the white reference as the calculation criteria of reflectance varied according to the intensity of illumination. The reflectance at the cracked area was 5.65% lower in visible light and 4.58% lower in near-infrared light than that at the uncracked area. The detection of cracks may offer more precise results in further studies when the gimbal direction and camera angles of the drone are calibrated. Because hyperspectral imagery enables the detection of crack depths and types of clay minerals, which are difficult to identify in general RGB imagery, it can serve as a preemptive measure for evaluating the embankment stability.