• Proceedings of the Korea Water Resources Association Conference
• /
• 2017.05a
• /
• pp.153-153
• /
• 2017

최근 10년간 집중호우로 인한 홍수 피해는 심각한 수준으로 발생하고 있어 호우피해액의 경우 3조3111억원의 손실을 입었다(국민안전처, 2015). 이를 대비하기 위하여 국내에서는 홍수피해에 취약한 지역을 파악하기 위한 연구는 다양한 측면으로 이루어져 왔다. 하지만 기존의 연구사례에서는 취약성 평가를 위한 인자를 구성함에 있어 연구자의 주관이나 선행연구 사례를 토대로 선정하였기 때문에 실제로 호우피해에 대한 원인을 파악하기에는 다소 부족한 면이 있다. 만약 호우피해에 대한 원인을 면밀하게 분석하고 직접적인 원인을 파악할 수 있다면, 향후 지역별 취약성 평가나 복원탄력성 평가 등에 관련한 연구에 있어 기존의 비해 더 확실한 결과를 도출할 수 있을 것으로 판단된다. 이에 본 연구에서는 지역적 특성이 상이한 5개의 지역을 선정하여 호우피해가 발생되었던 사례를 토대로 기후조건과 사회?경제적 인자를 고려하여 직접적인 원인을 파악하고자 하였다. 호우피해가 가장 빈번하게 일어난 5개의 지자체를 선정하여 재해기간에 따른 강우패턴을 분석하였다. 그 결과 유사한 강우패턴으로 호우피해가 발생하여도 그로 인한 피해액은 상이한 결과를 나타낸 사례가 있었다. 이는 지자체별 재해유형과 재산정도, 도시화율, 인구밀도 등의 지역적 특성이 다르기 때문을 알 수 있었다. 따라서 본 연구에서는 지역적 특성이 다른 5개의 지역에 대한 재해유형 등을 파악하여 호우피해에 대한 원인을 도출하였고, 그 결과를 통해 취약성 평가 등과 같은 다양한 분석의 지표로 활용이 가능할 것이다. 또한 향후 방재예산을 투자하는데 있어 확실한 판단 기준으로 활용할 수 있을 것으로 판단된다.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2017.05a
• /
• pp.89-89
• /
• 2017

유기농업은 저농약, 무농약, 자연농법과 함께 환경 친화적 농업으로 인식되어 세계적으로 유기농산물 생산량 및 재배면적이 급격하게 증가하고 있다. 국내 역시 안전한 먹거리 생산과 재배환경에서의 유해물질 관리방안 구축 등이 필요한 상황이다. 자가생산 유기농자재, 가축분을 이용한 축분 퇴비와 액비, 그리고 유박 등이 유기농업에 활용되고 있으나 사용 유기농자재의 양분가용화와 양분이용효율에 따른 비점오염원 형태로 토양 및 수질에 미치는 환경영향 등의 관측과 분석이 필요한 실정이다. 따라서 본 연구의 목적은 밭 포장에서의 유기농업 적용에 따른 유기농과 관행농에서의 대표적 비점오염원인 영양물질(T-N 및 T-P)에 대한 원단위를 평가하는데 있다. 시험포장은 전북 순장군 순창읍에 위치하고 있으며, 유기질비료시비 및 관행작물(고구마)의 3반복 1처리구(경사도 $6.6^{\circ}$)와 관행농관리 및 관행작물(고구마)의 1반복 1대조구(경사도 $6.8^{\circ}$)로 구성하였다. 현장에서 강우량과 유량을 실측하였으며, 강우 이벤트 시 T-N 및 T-P의 수질항목을 샘플링 후 분석하였다. 2016년 현재까지 총 6회의 강우 이벤트가 발생하였으며, 그 중 4회의 수질 샘플링을 실시하였다. 유출률은 평균 유기농에서 32%와 관행농에서 57%로 나타났다. 이는 토지피복 및 선행강우 등의 영향으로 다양한 분포를 보여주었다. 유기농 처리구에서 수질 부하량이 전체적으로 높게 나타났으며, T-N의 경우 4.4배와 T-P의 경우 1.8배로 나타났다. 이러한 경향은 유출수의 농도 영향보다 유출량의 영향이 큰 것으로 보인다. 유기농 처리구의 경우 제초제 등의 농작업이 제대로 이루어지지 않아 조도계수가 높았으며, 유기농 처리구에서 유출량이 31% 수준으로 상대적으로 낮게 나타났다. 본 연구의 경우 관행적으로 이루어지는 제초관리 형태를 벗어난 경우로 일반적인 결론 도출에는 한계가 있으나 유기농업 경작지에서 일반적으로 식생분포가 활발한 특성을 보여주고 있다. 향후 추가적인 모니터링 연구가 지속적으로 필요하며, 본 연구를 바탕으로 유기농업 최적관리방안 제시에 필요한 기초자료로 활용되기를 기대된다.

• KIPS Transactions on Software and Data Engineering
• /
• v.8 no.10
• /
• pp.411-420
• /
• 2019

Camera model identification has been a subject of steady study in the field of digital forensics. Among the increasingly sophisticated crimes, crimes such as illegal filming are taking up a high number of crimes because they are hard to detect as cameras become smaller. Therefore, technology that can specify which camera a particular image was taken on could be used as evidence to prove a criminal's suspicion when a criminal denies his or her criminal behavior. This paper proposes a deep learning model to identify the camera model used to acquire the image. The proposed model consists of four convolution layers and two fully connection layers, and a high pass filter is used as a filter for data pre-processing. To verify the performance of the proposed model, Dresden Image Database was used and the dataset was generated by applying the sequential partition method. To show the performance of the proposed model, it is compared with existing studies using 3 layers model or model with GLCM. The proposed model achieves 98% accuracy which is similar to that of the latest technology.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2009.05a
• /
• pp.572-575
• /
• 2009

With the advent of integration environment of broadcasting and communication, IPTV has been widely used. It provides services such as information, movie contents and broadcasting through TV using super-high speed networks. Developments of Wireless LAN and IP network technology create various and fusional services such as IPTV, VoIP that are based on IP network. The development of Wireless LAN is very important in IPTV network field which requires the best quality of service on the security, QoS and bandwidth. In this Paper, We configure the experimental network in its RIP and OSPF environment to test the Video Quality of IPTV in Wireless LAN. We measure and evaluate broadcasting quality by using PSNR to show the corelation of Routing Protocols in Wireless LAN in which how they affect to the IPTV real-time Video Quality.

• Journal of Korea Port Economic Association
• /
• v.30 no.1
• /
• pp.57-71
• /
• 2014

Information which port provide to users including shipping companies is essential information for their business performance. Thus, information service of several services which port provide to shipping company is also very important port-logistics service. However, despite of this importance, there have been little research related to port-logistics information service. The aim of this study is to analyze the satisfaction of information service for port logistics. To achieve this objective, evaluation criteria consisting of 16 items based on the previous research was established. And satisfaction index that can effectively show the current level of information service for port logistics was developed. The results of analysis showed that satisfaction index of information service provided by Busan port was 61.90. And from the data analysis, it was revealed that current level of information service in whole area was less than 63 points. It was implied that improvement for overall port-logistics information service was needed. Finally, from the follow-up research, it was found that information service provided by Busan port have weakness in the aspects of unification of information and celerity of information.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2008.11a
• /
• pp.359-365
• /
• 2008

Turbopump test for a 30-ton-thrust liquid rocket engine was carried out using real-propellant. Liquid oxygen, kerosene, cold hydrogen gas were used for the oxidizer pump, the fuel pump, the turbine, respectively. The turbopump was run stably at the design and off-design conditions and the performance requirements were satisfied, which implies that the turbopump development at the engine subsystem level is successfully accomplished in the point of performance validation. This paper presents the results of a test where the turbopump was run for 75 seconds at three operating modes. In terms of performance characteristics of pumps and turbine, the results from turbopump assembly test using real-propellant showed a good agreement with those from the turbopump component tests using simulant working fluid.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2011.04a
• /
• pp.439-444
• /
• 2011

Doosan Heavy Industries & Construction Co., Ltd. has been recently developing the gas turbine engine using the biogas as fuel. This paper describes the non-reacting and reacting flow analysis of the combustor which is one of the main components in gas turbine engine. Through CFD analysis, investigation has been performed to evaluate the primary factors for aerodynamic design and to predict combustor behaviors during operation with various fuel distribution ratios. The calculation results are compared with rig test data, which reveals that CFD predictions such as pressure loss, air distribution ratio, and recirculation flow are quite reliable. The trend of NO formation was similar with the test, except the low fuel distribution ratio.

• Journal of the Society of Naval Architects of Korea
• /
• v.32 no.4
• /
• pp.105-113
• /
• 1995

A mechanical actuator to generate adjustable force ants its active control algorithm to minimize ship structural vibration are developed. The algorithms comprise initial algorithm which determines optimal phase and force magnitude of the actuator using the variation of vibration response according to the phase difference between the main engine and the actuator, and regulating algorithm which performs continuous optimal control to track the change of the engine speed. This control system can be applied without any prior identification for the dynamic characteristics of the controlled structure. In the control experiments for the deckhouse structural vibration of a 300,000 DWT crude oil carrier and a 2,270 TEU container carrier, the developed system showed good performance to reduce the vibration levels to $1/2{\sim}1/6$ of the uncontrolled levels.

• Journal of the Korea Society of Computer and Information
• /
• v.15 no.9
• /
• pp.129-136
• /
• 2010

With mobile computing, wireless sensor network and sensor technologies, ubiquitous computing services are being realized and could satisfy the feasibility of ubiquitous healthcare to everyone. This u-Healthcare service can improve life quality of human since medical service can be provided to anyone, anytime, and anywhere. To confirm the vision of u-Healthcare service, we've implemented a healthcare system for heart disease patient which is composed of two components. Front-end collects various signals such as temperature, blood pressure, SpO2, and electrocardiogram, etc. As a backend, medical information server accumulates sensing data and performs back-end processing. To simply transfer these sensing values to a medical team may be too trivial. So, we've designed a model based on context awareness for more improved medical service which is based on artificial neural network. Through rigid experiments, we could confirm that the proposed system can provide improved medical service.

• Journal of the Korea Society of Computer and Information
• /
• v.19 no.11
• /
• pp.73-79
• /
• 2014

In the period of rising the importance of software education, unplugged activities has drawn attention as one of the various educational approaches. It has a good reputation in educational effectiveness and usefulness in an aspect of learning the principle of computer science. This paper proposes the tool that allows unplugged learning contents to be used in the web based on HTML5 in order to enhance its merits and accessibilities. The proposed tool is easy to access because it is operated on the level of web browser with no plug in or extra application programs. In addition, as a learner focused contents aiming at interaction on the web environment, it is well organized for school class room.