• Geotechnical Engineering
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• v.32 no.4
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• pp.14-24
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• 2016

• Proceedings of the Zoological Society Korea Conference
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• 2003.08a
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• pp.160.1-160
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• 2003

No Abstract, See Full Text

• 건축구조
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• v.19 no.5
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• pp.69-77
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• 2012

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2015.10a
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• pp.399-400
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• 2015

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.49 no.3
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• pp.81-88
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• 2012

In this paper, we propose a novel speech enhancement algorithm for effective noise suppression in various noisy environments. In the proposed method, to result in improved decision performance for speech and noise segments, local speech absence probability (LSAP, local SAP) based on Teager energy of noisy speech is used as the feature parameter for voice activity detection (VAD) in each frequency subband instead of conventional LSAP. In addition, The presented method utilizes global SAP (GSAP) derived in each frame as the weighting parameter for the modification of the adopted TE operator to improve the performance of TE operator. Performances of the proposed algorithm are evaluated by objective test under various environments and better results compared with the conventional methods are obtained.

• Steel and Composite Structures
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• v.24 no.2
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• pp.227-237
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• 2017

This paper presents optimization of a long-span portal steel frame under dynamic wind loads using a surrogate-assisted evolutionary algorithm. Long-span portal steel frames are often used in low-rise industrial and commercial buildings. The structure needs be able to resist the wind loads, and at the same time it should be as light as possible in order to be cost-effective. In this work, numerical model of a portal steel frame is constructed using structural analysis program (SAP2000), with the web-heights at five locations of I-sections of the columns and rafters as the decision variables. In order to evaluate the performance of a given design under dynamic wind loading, the equivalent static wind load (ESWL) is obtained from a database of wind pressures measured in wind tunnel tests. A modified formulation of the problem compared to the one available in the literature is also presented, considering additional design constraints for practicality. Evolutionary algorithms (EA) are often used to solve such non-linear, black-box problems, but when each design evaluation is computationally expensive (e.g., in this case a SAP2000 simulation), the time taken for optimization using EAs becomes untenable. To overcome this challenge, we employ a surrogate-assisted evolutionary algorithm (SAEA) to expedite the convergence towards the optimum design. The presented SAEA uses multiple spatially distributed surrogate models to approximate the simulations more accurately in lieu of commonly used single global surrogate models. Through rigorous numerical experiments, improvements in results and time savings obtained using SAEA over EA are demonstrated.

• The Korean Journal of Ecology
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• v.17 no.3
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• pp.333-344
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• 1994

Community structure and habitat characteristics of Acer mono stands were studied in Mt. Giri $(127{\circ}35'E.,\;35{\circ}18'N)$ and Mt. $Baekun(127{\circ}38'E.,\;35{\circ}05'N)$. The vegetation was investigated by the Braun-Blanquet's phytosociological method. Distribution of Acev mono was most abundant on eastern and western slopes in valley side. The community structure was composed of 4 layers and average number of species appeared in each quadrat was 24. Habitats were almost covered with exposed rocks and the surface soil was classified to clay loam. The isothermal date lines of Mt. Giri and Baekun were 130 and 120 days, respectively, which is the number of days with mean daily minimum temperature below zero during the year. The daily range of temperature was compared at 4 regions during sap extraction.

• Journal of the Korean GEO-environmental Society
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• v.3 no.4
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• pp.19-27
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• 2002

Prediction of exact soil loss yield has as important engineering meaning as prediction of exact flow measurement in a stream. The quantity of soil loss in a stream should be considered in planning and management of water resources and water quality such as design and maintenace of hydraulic structures : dams, weirs and seawalls, channel improvement, channel stabilization, flood control, design and operation of reservoirs and design of harbors. In this study, the soil loss of Sap-gyo reservoir watershed is simulated and estimated by RUSLE model which is generally used in the estimation of soil loss. The parameters of RUSLE model are selected and estimated using slope map, landuse map and soil map by GIS. These parameters are applied to RUSLE's estimating program. And soil loss under probability rainfall in different frequencies are estimated by recent 30 years of rainfall data of Sap-gyo reservoir watershed.

• Korean Journal of Plant Resources
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• v.13 no.1
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• pp.54-60
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• 2000

To investigate the effects of Oenanthe javanica sap (OJS) on plasma lipid composition, several biochemical parameters such as total cholesterol, HDL-cholesterol, triglyceride, GOT, GPT and malodialdehyde were compared in the four groups as follows: a normal group with basal diet, a control group with high-fat diet, a treatment group with high-fat diet and OJS 1 ml/kg, and the other treatment group with high-fat diet and OJS 1.5 mg/kg. In addition, the body weight change, food intake and food efficiency ratios were measured. In this study, treatment groups decreased plasma total cholesterol levels.

• Resources Recycling
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• v.24 no.1
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• pp.43-50
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• 2015

An extensive literature survey and personal communication with relevant experts made it possible to understand economic and technical feasibility of disposable diaper recycling. Commercial level of soiled diaper recycling technology is currently available from a Dutch company, Knowaste Co., who owns a proprietary separation technology of the pulps, plastics and super absorbing polymer (SAP). In Korea, on the other hand, pre-consumer diaper recycling technology without material separation at its infancy converts manufacturing scraps into refuse plastic fuel (RPF), container/truck cargo boards or automobile boards/sheets. Although previous studies on feasibility of post-consumer recycling in Korea showed mutually contradictory implication, it was found out in this research that significantly positive economic feasibility can be obtained with pre-consumer diaper recycling. Subsequent recycling R&D including pre-consumer scrap and policy support may expedite 'Establishment of Sustainable Society.