• Proceedings of the Korea Water Resources Association Conference
• /
• 2015.05a
• /
• pp.509-509
• /
• 2015

물 수요관리측면에 대한 정책을 수립하기 위해서는 현재 또는 장래에 대한 용수수급의 정확한 이해를 필요로 한다. 이를 위해서는 용수 수요량 및 공급량뿐만 아니라 여러 산정요소를 필요로 하는데, 그 중 회귀수량은 물이 이용되고 다시 하천으로 회귀되어 이용될 가능성이 있는 수량으로 정의되며, 용수수급 및 용수절약 측면에서 회귀 수량은 중요한 요소라 할 수 있다. 회귀수량 조사는 유역조사 사업 이래, 10년간 생?공용수를 중심으로 미시적, 거시적으로 조사를 시행하였으나, 측정 자료의 신뢰도, 조사방법 및 지점선정 등의 문제로 인하여 조사 성과의 활용성이 매우 낮은 실정이다. 수자원장기종합계획등에서는 수자원관련 계획 수립시 생?공용수의 회귀율을 65 %로 적용하고 있으나, 이는 1970년대 말의 사회적 여건 및 경제적 상황이 반연된 결과로 현재 상황에 적용되기 곤란하다. 따라서, 현재 실정에 맞는 회귀율 산정은 반드시 필요하게 된다. 본 연구에서는 기존 생활용수 회귀수량 산정 연구 한계를 보완하고 유역조사 시행을 위한 개선된 회귀수량을 산정하고자 한다. 본 연구는 서울시 중랑물재생센터 처리구역을 기반으로 중랑천유역을 시험유역으로 선정하였다. 기존 회귀수량 산정방법을 개선하기 위해 시험유역 회귀수량 산정을 위한 가용 자료 분석 및 용수흐름 네트워크 공간분석을 추가로 진행하였다. 가용자료로 시험 유역내 상수공급자료(정수장 공급량, 상수계통도, 유수 및 누수율), 하수처리자료(하수처리구역도, 하수처리계통도, 유입량 및 방류량) 및 기상자료(기상청 지점 및 AWS 강우자료)를 구축하였고 각각의 상수계통도 및 하수처리계통도로부터 용수 흐름 네트워크망을 구축하였다. 상수공급자료로부터 상수계통도 공급지역을 구분하여 월별 유수율에 따른 월별 실 공급량을 산정하였다. 하수처리자료로부터 시험유역에서의 월별하수처리 유입량 및 방류량을 산정하였다. 최종적으로 회귀율(하수처리 방류량/실 공급량)을 산정한 결과 연평균 회귀율은 각각 93.97 %(2011년), 95.02%(2012년)로 과잉 추정 되었으며 7 ~ 9월의 회귀율은 110 ~ 120 %로 유입량을 초과하였다. 이는, 하수처리로 유입되는 유입량의 하수관거는 합류식으로 구축되어 7 ~ 9월에 많은 양의 강우량이 우수관을 통해 하수처리장으로 이송되어 생활용수 이외에 자연적인 공급량으로 인한 것으로 분석되었다. 따라서, 월별 회귀율 산정을 위해서는 불투수층에서의 면적강우량(mm)을 유입량(m3/s)으로 환산된 값을 고려하여 회귀율을 재산정하였다. 그 결과 연평균 회귀율은 각각 78.27 %(2011년), 77.58 %(2012년)로 나타났다.각각의 월별 회귀율도 매우 유사하게 나타났으며 과거 관용적으로 사용된 65 % 회귀율보다 약 12 ~ 13%로 증가하였으며 이는, 하수처리시설 구축 및 처리효율의 증가와 상수처리시설의 관로시설의 개량으로 인한 유수율 및 누수율 감소로 회귀율이 증가한 것으로 판단된다.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.39 no.1
• /
• pp.165-174
• /
• 2019

As a nonstationarity is observed in hydrological data, various studies on nonstationary frequency analysis for hydraulic structure design have been actively conducted. Although the inherent diversity in the atmosphere-ocean system is known to be related to the nonstationary phenomena, a nonstationary frequency analysis is generally performed based on the linear trend. In this study, a nonstationary frequency analysis was performed using climate indices as covariates to consider the climate variability and the long-term trend of the extreme rainfall. For 11 weather stations where the trend was detected, the long-term trend within the annual maximum rainfall data was extracted using the ensemble empirical mode decomposition. Then the correlation between the extracted data and various climate indices was analyzed. As a result, autumn-averaged AMM, autumn-averaged AMO, and summer-averaged NINO4 in the previous year significantly influenced the long-term trend of the annual maximum rainfall data at almost all stations. The selected seasonal climate indices were applied to the generalized extreme value (GEV) model and the best model was selected using the AIC. Using the model diagnosis for the selected model and the nonstationary GEV model with the linear trend, we identified that the selected model could compensate the underestimation of the rainfall quantiles.

• Journal of The Korean Association For Science Education
• /
• v.38 no.6
• /
• pp.825-838
• /
• 2018

The purpose of this study is to develop a survey tool of scientific character for elementary student which connects science education and character education effectively by figuring out traits of elementary students' character being presented in teaching and learning context of elementary school science. For this, we adapted the theocratical model from the previous research which defined scientific character as the competencies being able to practice in concrete teaching and learning context of science. Based on this model, we developed the survey tool as 'Scientific Character Inventory for Elementary Student' to assess elementary students' scientific character as the competences to practice the virtues being pursued in the context of elementary school science and verified its reliability and validity. As a result of an exploratory and confirmatory factor analysis, we confirmed all the items could be summarized into 28 items and eight constructs such as scientific problem-solving, self-management, self-reflection, communication, interpersonal skill, community participation, global citizenship, and environmental ethics awareness. We found that minimum reliability coefficient of constructs was over than 0.5 and reliability coefficient of the total items was 0.878. And also, there was modest relationship between each construct and the total score of scientific character. These results show that the developed survey tool can be useful in evaluating the effectiveness of science character education. This study is meaningful in that it systematically reveals constructs of scientific character which can be raised in concrete context of science teaching and learning so as to suggest the survey tool to assess this.

• Korean Journal of Heritage: History & Science
• /
• v.46 no.1
• /
• pp.346-361
• /
• 2013

Since the Ming Castle located in Nanjing was designated by the Government of China as a cultural property in 1988, the Nanjing city government has been conserving the castle according to its plan and thus restoring the historical and cultural values of Nanjing. The project is still in progress, and in this regard, a series of logistics have formulated and a lot of discussions have taken place. Likewise, Korea has been carrying out multidirectional policies to conserve and utilize castles lying throughout the country, appreciating the historical and cultural resources of castles lying throughout the country, and at the same time gets down to designation as the World Heritage. This study focused on how Nanjing, not only a castle city but also a historical city, had established a principle and legal foundation regarding the protection of the Ming Castle, especially on how the problems, which might continually arise in a process where a scheme reached a working stage, had been solved. The problem-solving process is expected to have great implications for Korea in a similar situation. Hereat, this study analyzed the project plans formulated seasonally and gathered data on practical operation by conducting interviews with hands-on workers. The results showed that Nanjing had carried out policies to utilize the castles as tourism resources by harmonizing cityscape and ecological environment, but that it well conserved castles without damaging cultural assets. The stereoscopic protection system for the Ming Castle, based on the consideration of historical and cultural environments, may provide practical and useful data for Korea's administration mapping out for a castle conservation policy and designation as the UNESCO World Heritage.

• Journal of Navigation and Port Research
• /
• v.43 no.1
• /
• pp.72-78
• /
• 2019

The second-hand ship market provides immediate access to the freight market for shipping investors. When introducing second-hand vessels, the precise estimate of the price is crucial to the decision-making process because it directly affects the burden of capital cost to investors in the future. Previous studies on the second-hand market have mainly focused on the market efficiency. The number of papers on the estimation of second-hand vessel values is very limited. This study proposes an artificial neural network model that has not been attempted in previous studies. Six factors, freight, new-building price, orderbook, scrap price, age and vessel size, that affect the second-hand ship price were identified through literature review. The employed data is 366 real trading records of Panamax second-hand vessels reported to Clarkson between January 2016 and December 2018. Statistical filtering was carried out through correlation analysis and stepwise regression analysis, and three parameters, which are freight, age and size, were selected. Ten-fold cross validation was used to estimate the hyper-parameters of the artificial neural network model. The result of this study confirmed that the performance of the artificial neural network model is better than that of simple stepwise regression analysis. The application of the statistical verification process and artificial neural network model differentiates this paper from others. In addition, it is expected that a scientific model that satisfies both statistical rationality and accuracy of the results will make a contribution to real-life practices.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.29 no.2
• /
• pp.71-76
• /
• 2019

Recently, the demand of labels for product management is increasing, as the automation system becomes more common. the development of functional labels which can be used in various environments has been rapidly proceeded. In the case of a printed circuit board, barcode labels with thermal and chemical stability are generally used due to a high temperature process around $300^{\circ}C$ and chemical cleaning in the manufacturing process. However, the yellowing phenomenon of labels that can lower the resolution of printed barcode image still needs to be prevented. In this study, we prepared a composite coating layer using a silica inorganic binder and a titanium dioxide white pigment, and developed a functional labels with thermal and chemical stability. The silica inorganic binder prepared by sol-gel process was confirmed to show excellent adhesion and abrasion resistance with the polyimide film. The white coating layer could be formed on the polyimide film with mixing the silica inorganic binder and titanium dioxide white pigment. The prepared coating layer showed excellent whiteness and glossiness above $400^{\circ}C$. The excellent chemical stability of the coating layer was also confirmed by the chemical treatment with acidic (pH 1.6) and basic (pH 13.6) cleaners.

• KIPS Transactions on Software and Data Engineering
• /
• v.10 no.8
• /
• pp.287-300
• /
• 2021

Collaborative Cyber-Physical Systems (CCPS) are those systems that contain tightly coupled physical and cyber components, massively interconnected subsystems, and collaborate to achieve a common goal. The safety of a single Cyber-Physical System (CPS) can be achieved by following the safety standards such as ISO 26262 and IEC 61508 or by applying hazard analysis techniques. However, due to the complex, highly interconnected, heterogeneous, and collaborative nature of CCPS, a fault in one CPS's components can trigger many other faults in other collaborating CPSs. Therefore, a safety assurance technique based on fault criticality analysis would require to ensure safety in CCPS. This paper presents a Fault Criticality Matrix (FCM) implemented in our tool called CPSTracer, which contains several data such as identified fault, fault criticality, safety guard, etc. The proposed FCM is based on composite hazard analysis and content-based relationships among the hazard analysis artifacts, and ensures that the safety guard controls the identified faults at design time; thus, we can effectively manage and control the fault at the design phase to ensure the safe development of CPSs. To justify our approach, we introduce a case study on the Platooning system (a collaborative CPS). We perform the criticality analysis of the Platooning system using FCM in our developed tool. After the detailed fault criticality analysis, we investigate the results to check the appropriateness and effectiveness with two research questions. Also, by performing simulation for the Platooning, we showed that the rate of collision of the Platooning system without using FCM was quite high as compared to the rate of collisions of the system after analyzing the fault criticality using FCM.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2019.10a
• /
• pp.47-47
• /
• 2019

미얀마 Indo-Burma 지역은 13,500종의 식물종이 분포하고 있는 생물다양성 핫스팟이다. 북부 산악지역에서 남부의 망그로브 지역에 이르는 다양한 특성의 생태계로 구성되어있다. 그러나, 풍부한 생물 다양성은 인간에 의해 인위적인 간섭, 개발, 모노크림 재배와 같은 지속적인 삼림 벌채로 위협 받고 있다. Dprovidedc와 Krupnick (2018년)은 123과 472종의 미얀마 약용식물을 학명, 영명, 미얀마 식물명 그리고 미얀마 현지에서 쓰이고 있는 약용식물의 활용 및 보존 상태를 종합적으로 정리했다. 이 중 약 13%가 보존 상태에 대한 평가를 받았으며 IUCN의 멸종 위기 종 목록(IUCN2017)에 등재되었다. 비록, 전국에 다양한 식물 및 생물 다양성이 분포되어 있지만, 미얀마는 여전히 지속 가능한 관리와 사용을 위한 인적자원과 시설이 부족하다. 국립수목원(KNA)은 2013년부터 미얀마 천연자원환경보전부(MINISTRY OF NATURAL RESOURCES AND ENVIRONMENTAL CONSERVATION, MONREC)와 미얀마 산림과학원(Forest Research Institute, FRI)과 함께 미얀마 보호지역 및 Saggaing 지역 내 식물 다양성 보존을 위한 공동 현장조사, 연구 및 출판 등의 협력사업을 진행하고 있다. 또한 국립수목원(KNA)는 약용으로 가치가 있는 미얀마 식물 생체를 수집, 현지외 보전 중이며 이중 65과 326종의 식물 생체를 국립수목원(KNA)에 있는 열대식물자원연구센터에 보존과 교육 목적으로 전시 중이다. 이 기증은 미얀마에서 식물생체를 국외로 반출한 첫 번째 사례이며 국립수목원(KNA)은 2008년 독일에서 열대식물을 기증받은 사례 다음으로 두 번째로 외국 정부의 공식적인 대량 식물 도입 사례이다. 도입한 식물 중 Santalum album L. 과 Amorphopallus paeoniifolius (Dennst.) Nicolson. 은 IUCN Red List of Threated Spiences (IUCN2017)에 취약(Vulnerable, VU), 관심필요(Least Concern, LC)로 분류되어 있다. 국립수목원 (KNA)는 2019년 6월 17일 개최된 "2019 아태지역 산림주간 및 28차 아태지역 산림위원회"에 참가하여 미얀마 도입식물 전시회를 개최 하였고, 국내 최초로 Amorphopallus paeoniifolius (Dennst.) Nicolson.의 Leaf Cycle을 타임랩스 촬영하여 국립수목원 웹진(10월 호) 과 YouTube에 연구성과를 홍보하고 있다. 또한 국립수목원 열대식물자원연구센터는 2,700여종의 미얀마, 라오스 등 무한한 가치를 지닌 열대식물의 수집 보전으로 기초 응용 연구기반을 구축하여 국민들에게 열대식물의 중요성과 잠재적인 자원가치를 알리는 역할을 하고 있다.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.22 no.3
• /
• pp.252-260
• /
• 2021

For frailty management, the importance of resistance exercise has been emphasized, and various devices have been developed. Recently, digital weight control technology that converts electromagnetic resistance to a digital weight is attracting attention, but there are no reports confirming the effectiveness and safety of the device for seniors in Korea. This study conducted a biomechanic-based ergonomic analysis of an elderly-friendly exercise device utilized in digital load control technology to suggest a direction for development. Twenty seniors (age: 62.40 ± 2.09 years) were included. The load of the device was classified into three levels, and the muscle activity and heart rate were assessed during three experimental motions. A questionnaire based on the International Organization for Standardization 9241-11 was adopted to evaluate the stability, operationality, efficiency, and satisfaction with the software and device. The program could be divided into three exercise intensities that can be utilized in the field depending on whether the exercise load, muscle activity, and heart rate were consistent. The monitor size needed to be enlarged to make the menu Korean, reduce the device size, and minimize noise. Considering these findings, the development of an advanced age-friendly exercise device by improving the size, display, and noise is suggested.

• Journal of the Korea Society for Simulation
• /
• v.30 no.1
• /
• pp.103-112
• /
• 2021

In recent years, public bicycle systems are widely spread over the world according to the development of ICT technology. Since the public bicycle systems in large cities need to secure both publicity and convenience for citizens, analysis of various their issues from introduction to operation is required. In addition, it is also necessary to prepare for various scenarios for coexistence with the PM business, which is recently in the spotlight as a last mile means and normally managed privately. This paper introduces modeling and simulation for efficient operations of public bicycle systems. In particular, the proposed method was developed in a form that can be easily used in other cities by modeling the general structure and behavior of the public bicycle system, and it was developed to facilitate modification and expansion of the future model with a component-based model configuration. This paper provides a case study of the propose method, which is the public bicycle simulation in Sejong City. The simulation results were derived by applying the data from the public bicycle system of Sejong City, and they were verified with the associated real data of Sejong City. Using the verified model, it is expected that it can be used as a tool to design and analyze various services on the public bicycle systems, which were especially suitable for Sejong City.