• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.4
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• pp.705-716
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• 2017

As many environmental pollution problems have arisen, various studies related to the environmental evaluation have been carried out in the construction industry. However, there is no methodology for estimating the environmental load quickly for design alternatives of civil facilities in the design phase. This study aim to establish criteria of works information and designed parts which can efficiently estimate environmental loads of PSC beam bridge based on standard quantity at the early design phase. For this purpose, a detailed environmental loads database was constructed by performing Life Cycle Assessment (LCA) based on detailed design data of 25 bridges. In addition, major work with high impact on environmental load were selected, and the analysis of characteristics of environmental load according to the required materials and 8 impact categories were conducted. As a result, the superstructure accounted for 42.91%. In the superstructure, remicon of the material base and PSC beam work occupied 53.13% and 31.25%. In the substructure, remicon, rebar, and cement, which are material base, accounted for more than 93%. It is expected that this major work and material information for each part of bridge can be utilized in the construction of the model, which can estimate the approximate environmental load, reflecting the characteristics of the structure in the design phase.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.5
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• pp.751-760
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• 2018

Currently, the quality measurement of the work is carried out by the supervisor's visual inspection, as the workers individually judge the number of resolutions, thickness, speed and vibration. After work, we are conducting follow-up work through traditional spot test, which is less representative. Therefore, it is impossible to check the results of the resolution, and there is always the possibility that problems will arise due to poor construction. This study demonstrates the feasibility of using the continuous compaction strength measurement method by comparing the continuous compaction strength measurement method and the conventional compaction strength measurement method after performing the compaction in the actual field scale in various test conditions. The validity is verified by analyzing the Compaction Meter Value of an Intelligent Compaction roller composed of a Global Positioning System and an accelerometer, Based on the proven results, a full range of quality can be confirmed without a single test. The quality confirmation is visualized in the compaction control program developed in this study, This enables the field manager to perform real-time quality monitoring at the same time as compaction.

• Journal of the Korea Computer Graphics Society
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• v.16 no.4
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• pp.25-33
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• 2010

With the popularization of digital photography, people are now capturing and storing far more photos than ever before. However, the enormous number of photos often discourages the users to identify desired photos. In this paper, we present a novel method for fast and intuitive browsing through large collections of geo-referenced photographs. Given a set of photos, we construct a hierarchical structure of clusters such that each cluster includes a set of spatially adjacent photos and its sub-clusters divide the photo set disjointly. For each cluster, we pre-compute its convex hull and the corresponding polygon area. At run-time, this pre-computed data allows us to efficiently visualize only a fraction of the clusters that are inside the current view and have easily recognizable sizes with respect to the current zoom level. Each cluster is displayed as a single polygon representing its convex hull instead of every photo location included in the cluster. The users can quickly transfer from clusters to clusters by simply selecting any interesting clusters. Our system automatically pans and zooms the view until the currently selected cluster fits precisely into the view with a moderate size. Our user study demonstrates that these new visualization and interaction techniques can significantly improve the capability of navigating over large collections of geo-referenced photos.

• Journal of the Korea Concrete Institute
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• v.23 no.3
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• pp.377-384
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• 2011

Although concrete is considered as fire proof materials, high strength concrete shows severe material and structural damages when exposed to fire. To understand such damages in high strength concrete structures, the effects of various design parameters and fire condition on the thermal behaviors of high strength concrete structures are investigated in this study. In order to achieve this goal, fire tests are performed on high strength concrete columns with different fire conditions and design parameters including cross sectional area, cover thickness, and reinforcement alignment. To investigate thermal behaviors, temperature distributions and amount of spalling are measured. In overall, the columns show rapidly increasing inner temperatures between 30~60 mins of the fire tests due to spalling. In detail, the higher temperature distributions are observed from the columns with the larger cross section and less cover thickness. Moreover, among the columns with same reinforcing ratio, larger number of reinforcements with the smaller diameter causes the higher temperature distribution. The findings from the experimental study allow not only understanding of thermal behaviors of high strength concrete columns under fire, but also guidance in revising fire safety design.

• Journal of the Korea Convergence Society
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• v.8 no.7
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• pp.323-330
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• 2017

Emotion in early childhood has been observed to make an important effect on behavioral development. The teacher has coached to develop good behavior based on considering emotional response rather than rational response. This study was to determine significance of emotional coaching for behavior development according emotion recognized by non-verbal measurement system developed specially in this study. The participants were 44 people and were asked to study in four experimental situation. The experiment was designed to four situation such as class without coaching, behavioral coaching, emotion coaching, and emotion coaching based on emotional recognition system. The dependent variables were subjective evaluation, behavioral amplitude, and HRC (Heart Rhythm Coherence) of heart response. The results showed the highest positive evaluation, behavioral amplitude, and HRC at emotion coaching based on emotional recognition system. In post-doc analysis, the subjective evaluation showed no difference between emotion coaching and system based emotion coaching. However, the behavioral amplitude and HRC showed a significant response between two coaching situation. In conclusion, quantitative data such as behavioral amplitude and HRC was expected to solve the ambiguity of subjective evaluation. The emotion coaching of teacher using emotional recognition system was can be to improve positive emotion and psychological stability for children.

• Journal of Environmental Science International
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• v.4 no.4
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• pp.367-377
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• 1995

The study of flocculation kinetics is of fundamental interest in the field of water treatment, because rational study of the factors affecting the coagulation process should be based on the rate of particle growth. The effect of sulfate on flocculation kinetics were examined using ferric nitrate as a coagulant to coagulate kaolin clay in water under several experimental conditions. Both the particle size distribution data obtained from the AIA and the on-line measurement of turbidity fluctuation by the PDA were used to measure flocculation kinetics. Results show that sulfate ion added to the kaolin suspension played an important role in the flocculation process, not only improving flocculation kinetics at more acidic pH levels but also changing surface charge of particles. The kinetics of flocculation were improved mainly by the enhanced rate and extent of Fe(III) precipitation attributed to the addition of sulfate, and thereby, better interparticle collision frequency, but little by the charge reductions resulting from the sulfate addition. The increase in sulfate concentration beyond $3\times10^{-4}M (up to 2\times10^{-3}M)$ did not induce further improvement in flocculation kinetics, although the higher concentrations of sulfate ion substantially increased the negative ZP value of particles. Key Words : Flocculation Kinetics, Fe(III) Coagulant, Sulfate ion, Turbidity Fluctuation.

• 한국지구과학회:학술대회논문집
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• 2010.04a
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• pp.110-110
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• 2010

2009년 7월 23일-24일 양일간의 APEC MTF 컨퍼런스는 APEC 회원 경제가 아시아-태평양지역에서 광업부문의 지속가능한 발전의 주제를 토의할 기회를 제공했다. 본 컨퍼런스는 APEC의 광업부문의 지속가능한 발전이라는 프로젝트의 중요 부분이며 컨퍼런스의 활발한 참여는 프로젝트의 성공을 증진시켰다. 지속가능한 발전에 대한 안건이 수년간 APEC의 핵심부분이었으며, 특히 광업장관(MRM)회의에 상정되어 왔다. 2004년 6월 칠레 안토파가스타의 제1차 회의에서, 광업장관들은 APEC 지역에서 광업 및 금속산업의 지속가능한 발전은 부를 창출하고, 환경사업을 창출하며, 사회적으로 책임있는 발전을 도모하며 사회를 위한 향상된 가치를 만들어낸다는데 동의했다. 초기의 action item들 중에서 지속가능한 발전에 있어서 광물 및 금속의 기여를 규명하는 것도 있었다. 광업에 있어서 지속가능한 발전에 대한 안건의 토의는 2005년 10월 한국의 경주 제2차 APEC MRM 회의에서 속계되었다. 관련된 action task는 채광 후 토지운영 뿐만 아니라 에너지 효율기술, 광업 오염 통제 기술과 같은 환경친화적인 채광기술에 대한 정보교환 및 협조를 독려하는 것이었다. 2007년 호주 퍼스의 제3차 회의에서 APEC MRM 회의는 특히 지구화의 시대에 APEC 지역 광물자원의 지속가능한 발전에 대한 긴밀한 지역적 협조에 대한 필요성을 인지하고 있다. 장관들은 역시 광업부문에서 지속가능한 발전에 대한 APEC 위상을 정립하기 위한 작업을 주도하기로 했으며 APEC 경제의 공통관심사를 UNCSD에 반영키 위한 자료제공을 하기로 결정했다. APEC 광업분야의 지속 가능한 개발에 관한 APEC MTF회의는 호주, 캐나다, 칠레, 중국, 인도네시아, 일본, 말레이시아, 파푸아 뉴기니, 페루, 필리핀, 한국, 러시아, 싱가포르, 타이완, 태국, 미국, 베트남에서 자신들의 지속 가능한 개발을 위한 활동에 관한 발표나 의견을 제시하였다. 세계 은행이나 AIM에서도 발표를 하였다. 중요한 소주제들은 다음과 같다. $\cdot$ APEC MTF가 APEC 광업분야의 지속 가능한 발전을 추구하는데 있어 적절한 포럼이라는 것 $\cdot$ 기업들이 사회적 책임(CSR)을 성실히 이행할 필요가 있다는 것 $\cdot$ 수자원과 인적자원의 부족을 다룰 필요가 있다는 것 $\cdot$ 적절한 광산 복구가 필요하다는 것이다. 한국은 "광업분야의 지속가능한 발전을 위한 환경과 광업간의 균형"이라는 프로젝트 아이디어를 제안했다. 인도네시아와 말레이시아는 한국측 프로젝트 수행의 중요성을 강조했다. 러시아 연방은 "광업에 있어 투자 활성화"라는 프로젝트 아이디어를 제안했다. 이 관점에서 MTF는 APEC 투자전문가 그룹과의 협력을 지지했으며 이 포럼간 활동을 활성화시키기 위하여 APEC 사무국에 요청했다. 이 프로젝트는 세계 광업분야의 투자를 증진시키는 최적관행 분석에 따라 제안될 것이고 수행될 것이다. 말레이시아는 광업 및 광업 산업의 지속가능한 발전지시자를 위한 역량구축 프로젝트를 제안했다. 태국은 말레이시아의 제안을 지지했으며 공동프로젝트를 제안했다.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.4
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• pp.313-319
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• 2015

This study relates to an investigation into semi-dry manufacturing process of BP sludge based on non-heating production method. In this study, we conducted a research into reduction of water content ratio which arose from mixture of BP by-products of high water content ratio(50% or higher) with industrial by-products to use such BP by-products as construction materials in large quantity. We measured the reduction rate of water content ratio at the feeding ratio of water content reduction agent(1:0.5) in BP by-products. The results showed that water content ratio was the lowest with 18.5% in the mixture of PA+CFA(1:0.5). Moreover, water content ratio ranged between approximately 9.2% and 11.4% at the age of 1 day to 2 days at the aging temperature of $20-30^{\circ}C$, suggesting that the water content ratio was in the range within 10% which was a level suitable for use as construction material in this study. Meanwhile, we compared and evaluated the physical properties of non-heated BP by-products based on post-aging pulverization method. The results showed that there was no significant difference, depending on pulverization method. When production efficiency and economic feasibility were taken into consideration, it was found desirable to use fine particle pulverizer or pin mill enabling continuous production.

• Journal of the Korean Data and Information Science Society
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• v.28 no.2
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• pp.339-348
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• 2017

One of the major issues of statistical process control for variables data is monitoring both the mean and the standard deviation. The traditional approach to monitor these parameters is to simultaneously use two seperate control charts. However there have been some works on developing a single chart using a single plotting statistic for joint monitoring, and it is claimed that they are simpler and may be more appealing than the traditonal one from a practical point of view. When using these control charts for variables data, estimating in-control parameters and checking the normality assumption are the very important step. Nonparametric Shewhart-Lepage chart, proposed by Mukherjee and Chakraborti (2012), is an attractive option, because this chart uses only a single control statistic, and does not require the in-control parameters and the underlying continuous distribution. In this paper, we introduce the Shewhart-Lepage chart, and propose the design procedure to find the optimal diagnosis limits when the location and the scale parameters change simultaneously. We also compare the efficiency of the proposed method with that of Mukherjee and Chakraborti (2012).

• Journal of the Korean Electrochemical Society
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• v.19 no.2
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• pp.39-44
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• 2016

Oxygen reduction reaction in the fuel cell (ORR) plays a dominant role in the overall reaction. In addition, the low compatibility between the membrane and the binder consisted of different materials, greatly reduces the efficiency of the fuel cell performance. In view of these two problems, geometrically modified copolymers with 9.9_Bis (4-hydroxyphenyl) were synthesized via condensation reaction instead of conventional biphenol and were adopted as hydrocarbon ionomer binders. By utilizing these binders, two kinds of MEAs using fluorinated Nafion membrane and hydrocarbon based membrane were manufactured in order to electrochemical performance evaluation. With current-voltage curves, there was no significant difference in the 0.6 V when two types of membrane were applied. Also, tafel slope became considerably lower as compared to the Nafion membrane. Thus, it is determined that the new hydrocarbon binder is expected to contribute the improvement in performance of fuel cells.