• 한국시뮬레이션학회논문지
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• 제1권1호
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• pp.17-24
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• 1992

The capacity of the drilling process in Multi-Layer PCB fabrication can be affected by various process parameters determining material flows in the unit operations. The ratio of mass-lamination to pin lamination and the number of stacks as the most critical paramaters, among them, were chosen on the basis of exhaustive field evaluation to study their effects on the capacity of the process. The best alternative condition for maximum capacity of the process was selected by simulation of process.

• 한국주조공학회지
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• 제29권2호
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• pp.59-63
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• 2009

Effects of Ti on damping capacity and mechanical properties are investigated in hot rolled Fe-17%Mn alloy. The existing damping alloy with Fe-Mn binary system was limited the use by high production cost, however in case of using scrap iron instead of pure iron although the content of carbon is higher it is possible to be applied wider field especially construction items because the production cost is lower. However, the excellent specific damping capacity is dropped due to the high content of carbon, we developed advanced type of damping alloy included Ti. TiC is formed with added Ti and it holds the specific damping capacity similar to existing damping alloy. The effect of Ti on damping capacity is found to be beneficial in carbon-containing alloy, which is attributed to the depletion of carbon solute due to the formation of TiC.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 가을 학술발표회 논문집
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• pp.350-357
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• 2002

The scale effect should be considered to determine the bearing capacity and settlement of footings from Plate-Load Test, because of the size difference between a footing and a loading plate. To analyze characteristics of bearing capacity and settlement according to the difference of loading plate sizes, model tests were peformed with four different sizes of square plate, which is B=10, 15, 20 and 25cm respectively, on five different kinds of subsoil, which is pure sand(100:0), sand-clay mixed soil(75:25, 50:50, 25:75), and pure clay(0:100). Based on the analyzed results, this paper also proposed a method of bearing capacity and settlement determination, where scale effect is considered depending on the mixing ratio of sand and clay. Applying the formular proposed in this research to field problems, it is expected that evaluation of bearing capacity and settlement of footings can be more reliable and more economic construction can be achieved.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2009년도 추계학술대회 논문집
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• pp.267-271
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• 2009

This paper presents the improvement and application effect in fault restoration program based on distribution automation system(DAS) of KEPCO. When a fault occurs, fault restoration program can detect fault section based on FI information of DAS, and calculate the best restoration solution by comparing the load capacity of outage area and the spare load capacity of connected distribution lines, and propose switch operating procedure for fault section isolation and outage restoration. Fault restoration program was applied to real field and it was verified that this program is applicable to diverse field cases. By using this fault restoration program to the field human error can be reduced and fault procedure can be more reliable, accurate, and fast.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 총회 및 춘계학술발표회
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• pp.13-16
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• 2005

Laboratory and field experiments were conducted to study the effectiveness of five adsorbents for the removal of arsenic. The adsorbents included activated alumina (AA), iron coated AA (ICAA), and granular ferric hydroxide (GFH), granular ferric oxide (GFO), and granular titanium dioxide (GTD). Laboratory experiments were conducted to investigate arsenic removal using challenge water prepared in accordance with NSF International Standards 53 (ANSl/NSF 53-2001). Field experiments were conducted using arsenic-contaminated groundwater In laboratory experiment, the treatment capacity decreased in the following order GTD > GFO > GFH. In contrast, the treatment capacity decreased in the following order GFO > GTD > GFH > ICAA > Ah in field experiments.

• 한국산림과학회지
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• 제95권2호
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• pp.209-215
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• 2006

We investigated antioxidant capacity in leaves of 14 coniferous trees under field conditions. We focused on understanding the species characteristics on antioxidant systems and screening the coniferous tree species with the best antioxidant systems using their characteristics. The antioxidant capacity of 14 coniferous trees was divided into three groups. First group was Thuja orientalis and Chamaecyparis obtusa and those species had the highest content of ${\beta}$-carotene and xanthophyll. Second group, C. obtusa and Juniperus chinensis, used antioxidant enzymes to mitigate stress. C. obtusa represented high activity at superoxide dismutase (SOD), glutathione reductase (GR), and peroxidase (POD), and J. chinensis exhibited high activity at SOD, POD, catalase (CAT). Third group employed antioxidant such as ascorbic acid and ${\alpha}$-tocopherol. The antioxidant content of T. orientalis was the highest while that of Pinus parviflora and C. obtusa were the lowest. Few species belonged in three groups simultaneously, and most species belonged in at least one or two groups. In summary, we proposed that C. obtusa and T. orientalis had the highest antioxidant capacity while P. parviflora and P. desiflora for. multicalus had the lowest antioxidant capacity.

• 한국구조물진단유지관리공학회 논문집
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• 제23권4호
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• pp.53-60
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• 2019

이 연구에서는 정적 변위를 사용하는 유전자 알고리즘을 이용한 교량의 유한요소해석모델 개선 기법을 제안하며, PSC 거더교를 대상으로 한 실증시험 데이터를 이용하여 제안된 방법을 검증하였다. 실증 재하시험으로 정적재하시험과 의사정적재하시험을 수행하였으며, 각 재하시험의 계측 데이터를 이용하여 대상교량의 유한요소해석모델 개선을 진행하였다. 최종적으로 의사정적재하시험의 계측 데이터를 통해 개선된 모델을 이용하여 공용 내하력평가를 수행하였다. 내하력평가에는 현 도로교설계기준과 구 도로교설계기준, AASHTO LRFD의 설계 활하중을 이용하였으며, 각 설계기준 별 내하력평가 결과를 비교하였다.

• Computers and Concrete
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• 제33권5호
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• pp.573-594
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• 2024

This article presents a research study, with both laboratory and field tests, of a deep foundation in a markedly anisotropic medium. Particularly it has focused on the evaluation of the behavior of a pile, one meter in diameter, embedded in a rocky environment with difficult conditions, in the Flysch of the Spanish city of San Sebastián. To carry out the research, the site of a bridge over the Urumea River was chosen, which was supported by pre-excavated reinforced concrete piles. 4 borings were carried out, by the rotation and washing method, with continuous sampling and combined with flexible dilatometer tests. In the field, an Osterberg load test (O-cell) was performed, while in the laboratory, determinations of natural moisture, natural unit weight, uniaxial compressive strength (UCS), point load strength (PLS), compressive wave propagation velocity (V_c) and also triaxial and direct shear tests were carried out. The research results indicate the following: a) the empirical functions that correlate the UCS with the PLS are not always linear; b) for the studied Flysch it is possible to obtain empirical functions that correlate the UCS with the PLS and with the V_c; c) the bearing capacity of the studied Flysch is much greater than if it is evaluated by different load capacity theories; d) it is possible to propose an empirical function that allows evaluating the mobilized shear strength (τ_m), as a function of the UCS and the displacement relative of the pile (δ_r).

• Geomechanics and Engineering
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• 제38권3호
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• pp.261-273
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• 2024

This study presents a groundbreaking analytical approach to find an exact solution for the bearing capacity of strip footings on reinforced slopes, utilizing the two-phase approach and slip line method. The two-phase approach is considered as a generalized homogenization technique. The slip line method is leveraged to derive the stress field as a lower bound solution and the velocity field as an upper bound solution, thereby facilitating the attainment of an exact solution. The key finding points out the variation of the bearing capacity factor N_γ with influencing factors including the backfill soil friction angle, the footing setback distance from the slope crest edge, slope angle, strength, and volumetric fraction of inclusion layers. The results are evaluated by comparing them with those of relevant studies in the literature considering analytical and experimental studies. Through the application of the two-phase approach, it becomes feasible to determine the tensile loads mobilized along the inclusion layers associated with the failure zone. It is attempted to demonstrate the results by utilizing non-dimensional graphs to clearly illustrate variable impacts on reinforced soil stability. This research contributes significantly to advancing geotechnical engineering practices, specifically in the realm of static design considerations for reinforced soil structures.

• 농촌계획
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• 제22권4호
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• pp.131-138
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• 2016

Recently, the cultivated area is reduced, the ratio of upland-field in the total cultivated area is increasing relative appeared in 36.2% in 1990 from 43.7% in 2013. If upland-field can be applied well designed-infrastructure, good income crop production is possible, however, maintenance of infrastructure and a significant portion of the upland-field is maintained under insufficient infrastructure. While imports of agricultural products expanded since the 2000s in progress, looking at the self-sufficiency of upland-field crops, it is reduced to from 90% to 42% for the pepper, it is from 90% to 74% for the garlic, cereals is reduced from 42% by 26%. As a result of these conditions, the competitiveness of farmers has weakened, the risk to meet the challenges of this area of production and supply reduction increased. This study was the first to conduct a basic evaluation index, data analysis and evaluation of indicators to diagnose the agricultural production capacity of the upland field. 12 kinds classified index of producing conditions from the natural environment and eight factors for the cultivation and production capabilities have developed for the assessment of productivity of upland-field (especially Kimchi cabbage). Through this regional imbalance was found, based on the production capabilities conditions are good in Haenam, Gangneung, Pyeongchang. 3 Regions have been low and the lowest Youngwol to 0.8992. Climate(Cultivation conditions) indicators of Mungyeong region is the highest, relatively low areas were in Taebaek. In particular, it is determined to be preferred that the area required for the enhancing the production environment based on providing the convenience for the producing and maintenance of the first production area. It is necessary Increasing part of mechanization, agro-industrial competitiveness through aggressive management plans for facilities as required in the process of post-harvest storage, processing, distribution line can be improved.