• Journal of Elementary Mathematics Education in Korea
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• v.20 no.2
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• pp.193-213
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• 2016

This study has two goals. The First is to develop and apply a step-by-step program and the degree to which students' mathematical skills. The second is to analyze mathematical attitude change around the first grade students was done. The program for learning complement number is composed of series of 5 steps and 11 classes. Play for learning complement number, taking into account the difficulty of the learning steps 1-5 are organized. First step is composed of the classes which fragmented pieces of shapes to complete the entire geometry with fun activities for the entire part of the concept of learning and it maintenance concepts and can naturally learn by associating step. In second step, tools to take advantage of the real world and collecting the conservative concept. 3rd steps is to repair the mathematical concept of the parish in the learning stage of expansion. 4th step is halrigalri, number cards, making ten games etc. 5th step is to verify the concept of complement number and number operation ability. The concept of complement number through fun activities can improve students' mathematical skills, and mathematical attitude change. Early in the program, students use the finger to throw acid in the process. Simple addition and subtraction calculations may take a long time and error, but more and more we progress through the program using the fingers is eliminated and a more complex form calculations was not difficult to act out.

• Journal of the Korean Geosynthetics Society
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• v.11 no.2
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• pp.1-9
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• 2012

In order to review the utility of Lade's single hardening constitutive model, a series of isotropic compression-expansion tests and consolidated drained triaxial tests including as CTC, TC, RTC, and OSP were performed by Baekma river sand with various of stress path. Parameters required in model were determined using these tests. The accuracy of analysis was reviewed by back analysis of test results used to determine the 11 parameters of soil property through the test of each stress path. Also. for verifying the accuracy of prediction for the stress-strain behavior using failure criterion related 9 parameters with correlational equation and constant and yield criterion related parameters h, ${\alpha}$ and ${\eta}_1$, when stress path is different with each other, it has been obtained in the review result of stress path dependent characteristics of the constitutional model through the analyzing results of CTC, TC, RTC, OSP, and fine silica sand tests.

• Journal of Distribution Science
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• v.12 no.6
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• pp.21-29
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• 2014

Purpose - This research undertakes to understand the competitiveness of the steel distribution industry of both Korea and China to strengthen Korea-Sino economic cooperation, examines impediments to trade between the two countries to analyze causes which affect trade, and examines improvements in these areas to identify means of trade expansion. Through this survey of a defined period, we can identify the structural factors of trade dependence in the relationship between Korea and China. Research design, data, and methodology - The data were collected from the Korea Traders Association, the Korea Customs Office, and UN Comtrade, from which whole table indexes are calculated. The research methodology uses trade-related indexes to focus on analyzing comparative advantages based on time-series analysis statistics data (2000-2012) by using the analysis index of trade intensity index (TII), the revealed comparative advantage index (RCA), and the trade specialization index (TSI). Results - The export ratio for Korea to China was slightly higher in 2000 at 2.867, and the export ratio for Korea to China was sustained in 2005. However, it diminished gradually, reaching 1.263 in 2012. During the period 2000-2012, the indexes were maintained without any significant change. However, they still remain close to -1. In particular, in 2012 it is the closest it has ever been to -1. Therefore, China has a comparative advantage in export specialization. On the other hand, Korea has a comparative advantage in import specialization. For the research period, all indexes were much lower than 1, which means that Korea has consistently had a comparative disadvantage against China for the past 10 years when compared to other industries, even though it experienced improvement in 2000. Conclusions - The summary of conclusions based on empirical analysis research are as follows: First, per the trade intensity index of industries between the two countries, we conclude that the export ratio index in 2000 is 2.867, which means the export ratio of Korea to China is slightly higher. Furthermore, the ratios of 2.259 and 1.263 held in 2005 and 2012, respectively, meaning that the export ratio of Korea to China was maintained in 2005, but was diminishing gradually as the index in 2012 was 1.263. Second, per the trade specialization index of the steel distribution industry between Korea and China, the value was -0.379 in 2000, -0.368 in 2005 and -0.568 in 2012. Looking at the whole period of 2000-2012, the indexes remained without any significant change. However, they are still moving closer to -1. In particular, in 2012 it is the closest it has ever been to -1. Third, regarding the revealed comparative advantage index of the steel distribution industry between Korea and China, the RCA indexes in 2005 and 2012 are 0.246 and 0.306, respectively, which are still far from 1, even though the index has improved compared to the 2000's value of 0.0001. Therefore, the Korean steel distribution industry is at a significant comparative disadvantage to that of the Chinese steel distribution industry.

• Journal of Adhesion and Interface
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• v.15 no.3
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• pp.100-108
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• 2014

In this work, a series of molar ratios composed with YD-128 and DDM were chosen based on the viscosity analysis. The mixtures of YD-128 and DDM with the different molar ratios were cured at $170^{\circ}C$ for 15 min followed by post cure at $190^{\circ}C$ for two hours. The thermal properties of the cured samples were investigated with DSC, TGA, DMA, and TMA. The conversion ratio of the mixtures of YD-128 and DDM (1 : 1.1) was calculated by dividing ${\Delta}H$ obtained from DSC experiments for each cured sample by ${\Delta}H$. The TGA data of the cured samples showed that the thermal stability and thermal degradation activation energy were proportional to the amount of DDM in the mixtures. However, the highest tan ${\delta}$, and the lowest thermal expansion data with DMA and TMA respectively were obtained from the stoichiometric mixture of YD-128 and DDM. Furthermore, the different ratio of mixtures were applied to test specimens to be cured at $170^{\circ}C$ to measure single lap shear strength with universal testing machine.

• Korean Journal of Environment and Ecology
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• v.32 no.1
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• pp.39-46
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• 2018

Breeding bird surveys provide the reference information for understanding bird community structure and function in the ecosystem and conserving biodiversity. Recent rapid change of biodiversity due to climate change and other factors has made it necessary to utilize acoustic sensors for accuracy and spatial expansion of forest bird survey data and for time-series monitoring of forest birds. The objective of this study is to investigate the possibility of using acoustic recording sensor to evaluate the diversity of forest birds at breeding season by comparing and analyzing the recorded data of bird songs and field bird survey data. We conducted the site survey and recording in 186 points in 48 areas of 4 regions of Gombaeryeong and Jochimryeong around Jeombongsan Mountain and Jugryeong and Gochiryeong around Sobaeksan Mountain from May 2nd to 16th in 2013. The analysis of the correlation between the recording result and Bird Community Index based on the field survey showed that the number of bird species, population, and the number of bird songs by recording was significantly correlated to the number of species and population by field survey. Moreover, the number of bird species and the number of bird songs by recording showed a significant correlation to species diversity and species richness but no or low significant correlation to species evenness by the field study (observation and listing in parallel). As a result, it was possible to check species composition and species diversity of bird communities by analyzing acoustic recording data on the field. The acoustic recordings of bird songs in the breeding period were more reliable than the non-breeding period in the correlation of recording result and species diversity and for utilization.

• Journal of the Korea Concrete Institute
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• v.23 no.1
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• pp.49-55
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• 2011

The distresses of alkali-silica reaction (ASR) was recently reported at highway cement concrete pavement in Korea, which showed typical cracking and spalling patterns of ARS. Korea is was no longer safe zone against ASR, needding to find a control methodology against ASR. The purpose of this research was to provide a control methodology against ASR using mineral admixtures through a series of laboratory test program. Laboratory works included the accelerated mortar bar test (AMBT) by ASTM C 1260 regulation with five types of aggregate and three types of mineral admixtures (fly ash, ground granulated blast-furnace slag and silica fume). The result of ASTM C 1260 test for five types of aggregates without mineral admixtures showed that Siltstone and Mudstone were found to be "reactive." Tuff and Andesite-1 were found to be "possiblely reactive." In case of concrete mixed with 10, 20, and 30% fly ash, all specimens except Mudstone mixed with 10% FA were found to be "non-reactive". In cases of concrete mixed with 30, 40, and 50% ground granulated blast-furnace slag and 5, 7.5, and 10% silica fume, all specimens were found to be "non-reactive." These results could be selectively applied in constructions in Korea.

• Geotechnical Engineering
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• v.8 no.2
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• pp.5-20
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• 1992

The physical-based and lumped-parameter hydrologic groundwater flow model for predicting the rainfall-triggered rise of groundwater levels in hillside slopes is developed in this paper to assess the risk of landslides. The developed model consists of a vertical infiltration model for unsaturated zone linked to a linear storage reservoir model(LSRM) for saturated zone. The groundwater flow model has uncertain constants like soil depttL slope angle, saturated permeability, and potential evapotranspiration and four free model parameters like a, b, c, and K. The free model parameters could be estimated from known input-output records. The BARD algorithm is uses as the parameter estimation technique which is based on a linearization of the proposed model by Gauss -Newton method and Taylor series expansion. The application to examine the capacity of prediction shows that the developed model has a potential of use in forecast systems of predicting landslides and that the optimal estimate of potential 'a' in infiltration model is the most important in the global optimum analysis because small variation of it results in the large change of the objective function, the sum of squares of deviations of the observed and computed groundwater levels. 본 논문에서는 가파른 산사면에서 산사태의 발생을 예측하기 위한 수문학적 인 지하수 흐름 모델을 개발하였다. 이 모델은 물리적인 개념에 기본하였으며, Lumped-parameter를 이용하였다. 개발된 지하수 흐름 모델은 두 모델을 조합하여 구성되어 있으며, 비포화대 흐름을 위해서는 수정된 abcd 모델을, 포화대 흐름에 대해서는 시간 지체 효과를 고려할 수 있는 선형 저수지 모델을 이용하였다. 지하수 흐름 모델은 토층의 두께, 산사면의 경사각, 포화투수계수, 잠재 증발산 량과 같은 불확실한 상수들과 a, b, c, 그리고 K와 같은 자유모델변수들을 가진다. 자유모델변수들은 유입-유출 자료들로부터 평가할 수 있으며, 이를 위해서 본 논문에서는 Gauss-Newton 방법을 이용한 Bard 알고리즘을 사용하였다. 서울 구로구 시흥동 산사태 발생 지역의 산사면에 대하여 개발된 모델을 적용하여 예제 해석을 수행함으로써, 지하수 흐름 모델이 산사태 발생 예측을 위하여 이용할 수 있음을 입증하였다. 또한, 매개변수분석 연구를 통하여, 변수 a값은 작은 변화에 대하여 목적함수값에 큰 변화를 일으키므로 a의 값에 대한 최적값을 구하는 것이 가장 중요한 요소라는 결론을 얻었다.

• Management & Information Systems Review
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• v.36 no.3
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• pp.185-202
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• 2017

This study suggests the estimation of the demand for the exhibition center in Busan and to valid reasons for the establishment of the 2nd Convention Center in Busan. The validity for the estimated demand is acquired by examining the studies conducted by the Ministry of Commerce Industry and Energy. The qualitative data for the phased establishment of the area is suggested in accordance to the results of the demand estimation. From previous study(Oh, 2017), Kangseo-gu, Busan has been evaluated to be the final candidate for building a new convention center in the city of Busan. The potential synergy effects of on-going developmental projects in Kangseo region is one of the influential factors for the MICE professionals' opinion in the qualitative analysis. Moreover, the region has available land to hold the facility of more than 100,000 square meter to overcome the current drawback of BEXCO, insufficient space to hold large events. Lastly, the expansion of Gimhae International Airport would bring an increased international flights that would also lead to an increase in MICE industry for the region. The virtual effect of the more than one million $m^2$-sized oconvention center is examined via Huff Model and the results suggests a logical estimated data for further demand needed for the south east regions, not just within the city of Busan.

• Journal of Science and Technology Studies
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• v.12 no.1
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• pp.1-43
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• 2012

This paper examines the American Civil Liberties Union(ACLU)'s recent legal challenge on patents held by Myriad Genetics on two genes (BRCA1 and BRCA2) associated with a high risk of breast and ovarian cancer. Instead of analyzing the ACLU's objections to the BRCA patents in terms of its legal technicalities and normative ethical principles, this paper seeks to situate this legal case in the broader historical context of the shifting understanding of the relationship between private ownership, economic development, and the public interest in academic sciences. This paper first briefly chronicles a series of scientific developments and key legal decisions involving patenting of life forms, including genetically engineered micro-organisms animals and biological materials of human origins like cell cultures and genes, that led to the US Patent and Trademark Office(USPTO)'s official guidelines on human gene patenting in 2001. At another level, this paper analyzes the expansion of the scope of intellectual property rights in the life sciences in terms of shifting economic and legal assumptions about public knowledge and its role for economic development in the 1970s. I then show how these economic, legal, and ethical ideas that linked private ownership and the public interest have been challenged from the 1990s, calling for revisions in intellectual property laws regarding a wide array of life forms. The tragedy of the anticommons in human gene patenting, according to ACLU, has severely undermined creative scientific activities, medical innovations, access to health care and rights to life among cancer patient groups. ACLU's objection to human gene patenting on several US-constitutional grounds in turn suggests issues regarding intellectual property are critically linked to vital issues pertinent to the creative communities in arts and sciences, such as free exchange of ideas, censorship and monopoly, and free expression and piracy etc.

• The Journal of the Korea Contents Association
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• v.22 no.3
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• pp.500-512
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• 2022

Post-Occupancy Evaluation (POE), which is one of the construction environment evaluation methods, is a series of processes that ask about the functional requirements and satisfaction of an object from a life cycle perspective such as design/construction/residence. However, there are no POE research activities targeting large-scale units. On the other hand, large-scale third-phase new towns are being developed. Therefore, this study conducted a post-residence evaluation (POE) research activity in a large-scale unit (Multifunctional Administrative City). The procedure of this study is to conduct a literature survey on the current status and implications of the multi-functional administrative city area, and based on the research data, derive the Happy City evaluation index for the major issues and special issues of the Happy City. Afterwards, 450 questionnaires were conducted for the residents of Happy City, and POE analysis was performed on the derived data for each module. And based on the analysis results, implications such as problems and improvement points for the current status of the Happy City were derived. This can be used as a basis for the expansion of a large-scale new city into a self-sufficient city, and it can be used as a basic data for the development and improvement of a happy city that meets social needs in the future.