• 정보보호학회논문지
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• 제18권5호
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• pp.3-16
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• 2008

무선 센서 네트워크는 센서 노드 또는 모트(mote)라 불리는 소형 장치들로 이루어진 무선 네트워크이다. 최근 센서 네트워크에 대한 연구가 활발한 가운데 센서 네트워크에서의 보안에 관한 연구 또한 활발히 진행되고 있다. 센서 노드 및 센서 네트워크 상의 정보를 안전하게 저장, 전송하기 위해서는 암호 알고리즘의 구현이 필요하며, 이 암호 알고리즘들은 센서 노드의 한정된 자원을 효과적으로 활용할 수 있도록 효율적인 구현이 필수적이다. 센서 노드 상에서 이용될 수 있는 암호로는 TinyECC 등의 공개키 암호와 AES와 같은 표준 블록 암호가 있으나, 스트림 암호는 최근에서야 eSTREAM 프로젝트에서 표준화가 완료되어 아직 센서 노드상에서 사용 가능성이 명확하지 않은 실정이다. 이에 본 논문에서는 eSTREAM의 2단계와 3단계에 채택되었던 10개 소프트웨어 기반 암호들 중 9개의 암호들을 MicaZ 모트 상에 구현하여 성능을 비교하고, 특히 최종적으로 eSTREAM에 채택된 SOSEMANUK, Salsa20, Rabbit을 포함한 6개 암호에 대해서는 MicaZ에 적합하도록 최적화하였다. 또한 참조 구현으로써 하드웨어용 스트림 암호 및 AES-CFB에 대한 실험 결과도 제시한다. 본 논문의 실험에 따르면, 대부분의 스트림 암호가 약 31Kbps - 406Kbps의 암호화 성능을 보임으로써 센서 노드에서 사용하기에 큰 무리가 없음을 확인할 수 있었다. 특히 최종적으로 채택된 SOSEMANUK, Salsa20, Rabbit의 경우 센서 노드에 적합한 128바이트 크기의 작은 패킷의 암호화에서 각각 406Kbps, 176Kbps, 121Kbps의 속도를 보여주고, 70KB, 14KB, 22KB의 ROM및 2811B, 799B, 755B의 RAM을 사용함으로써, 106Kbps의 속도를 보여준 소프트웨어 기반 AES에 비해 우수한 성능을 보임을 알 수 있었다.

• 농촌지도와개발
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• 제8권2호
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• pp.245-261
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• 2001

The consulting industry had enjoyed growth rates over the past 20 years which show no signs of slowing in their momentum. Since 1995, it began to discuss institutionalization of consulting in the agricultural sector in Korea. Rural Development Adminstration has launched farm management consulting project by means of benchmarking for farming innovation in 1988, which consists of establishing consulting team, developing standard diagnosis form of sixty crops and materials, training consultants, having various public relations, and making information systems. Until October, 2001, sixty seven thousands of farmers have benefited on this project. It is now appreciated as a alternative for new agricultural extension approach. Analyzing the changes of farm management practice level through consulting shows improvement, which data have been stored in web database. It is expected that farm management consulting project be main stream of agricultural extension in this country.

• 한국시스템다이내믹스연구
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• 제12권1호
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• pp.59-74
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• 2011

This article deals with an economic evalutation of the 'Pasture Project of Kum River', which is the farming plan of mitten crabs in a stream of it. An augmented model of social capital is based on the past ecological-economic system dynamics model and elaborated further with suggestions of social capital literature. During the modeling process a chain diagram of causal relations and its relevant mathematical equations are presented for simulating the project performance, and the simulation results are provided to contrast the dynamic behaviors of the former ecological-economic model with ones of the new model incorporating social capital. The results indicate that an increase in the economic benefit of the project could happen in case of considering the process of social capital accumulation around the case area, which can be regarded as a remarkable trial to approve the common confidence in the role of social capital to enhance an economic achievement.

• 한국조경학회지
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• 제33권5호통권112호
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• pp.104-113
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• 2005

This landscape design proposal was presented for a competition for mixed-use development project by project financing in Asan Baebang which was held by the Korea National Housing Corporation in July of 2005. The site is a center of Asan Baebang New Town Development District and has a commercial area of $57,929m^{2}$. Design guidelines and judging criteria of this competition were to build a symbolic center and cultural core for district, to elevate positive image and identity of Asan New Town by attractive place making, to link with separated block in the site and regional context, and to make environmentally sustainable design by creating an attractive waterfront of Jang Jae stream passing through the site. This is the most important condition for the design. Therefore, the authors developed design concept and strategy within the guidelines and this conditions. The schema of the design was introduced by the water in the site. To evolve design concept, we reinterpreted water and context in the site combining with landscape design strategy. So the proposal set the main design concept as 'all that is solid melt into water' as if Marshall Berman said. By doing that, design concept of the proposal evolved as follows: 'extension' of water and greer, 'a joint' of space,'newness' of experience, 'breath' of consensus with each other. The spatial concept of this project was developed by expressing five theme spaces; eco zone, entertainment zone, art zone, culture zone, leisure zone. These theme spaces were consecutively placed along the pedestrian path and to consists of vertical layer in each level and diverse design technique and spatial effects are used.

• 농업과학연구
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• 제47권4호
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• pp.885-901
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• 2020

A forest watershed management project was introduced in 2004 to develop ecologically sound forest watersheds. It includes landslide prevention and erosion control, water resource management, landscape development, and forest resource management. However, it has been managed fragmentarily and inefficiently, far from the original intents. This study investigated current status, problems, and improvement measures of the project. Literature reviews were conducted on forest watershed management in Korea and other countries, and surveys were conducted on 201 erosion control experts. When introduced, the forest watershed management project was well planned and implemented as intended. It later turned to focus only on disaster prevention such as erosion control dams and stream conservation measures. The survey results showed that a majority (89% and 86%) of surveyees wanted increases in the project period and budget. They also responded that conflicts with local residents (51%) and determining project locations (32%) were the most difficult tasks when implementing the projects, and only 36% kept project records. To plan and implement the projects as intended, the following suggestions should be considered: (1) establishment of a solid legal foundation and improvement of the erosion control practices law; (2) increase in the project period (from 1 to 2 - 3 years) and budget; (3) development of a manual for project site selection and guidelines; (4) monitoring and systematic information management; and (5) development of spatial analysis tools for watershed analysis and management.

• 한국수자원학회논문집
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• 제40권5호
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• pp.359-369
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• 2007

본 연구에서는 소하천 환경조성사업을 위한 소하천자연도를 평가하기 위하여 기존 하천자연도 평가의 하천형태와 하천환경의 2개 부문과 14개의 항목에서 2개 항목을 추가하여 16개항목으로 보완하고 3개 항목을 정량화한 지표로 구성한 소하천자연도 평가방법을 제안하였다. 소하천 평면형상의 다양성을 위한 평가지표를 마련하기 위하여 경기 남부 지역에서 55개의 소하천을 선정하여 만곡도, 사행파장 등을 분석하였다. 대상소하천의 굴곡도는 대부분 1.2 내.외이었으며 개략적으로 소하천연장 약 500m 마다 1개의 사행파장을 보여 주고 있어 평면형상에 관한 평가지표 에 반영하였다. 또한 저수로폭의 다양성 평가항목을 정량화하는 지침을 제안하였다.평가 구간의 소하천길이는 경기 남부지역의 소하천 평면형 조사를 통하여 500m ${\sim}$ 1,000m 정도로 제시하였다. 제안된 소하천 자연도 평가 방법을 공사전.후 당왕소하천에 적용하여 소하천의 자연도를 평가함으로써 친환경조성사업의 효과를 평가하였으며, 수정.제안된 소하천 자연도 평가 방법은 소하천의 하천형태 및 하천환경을 적절히 반영하는 가능성을 확인하였다.

• 한국물환경학회지
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• 제36권5호
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• pp.445-452
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• 2020

Tributary is a part of life space for people and a very important place that accommodates rest recreation and other daily activities. absolutely insufficient basic data about water quality and flow rate are available for basin management. Efficient water and basin management systems, which are also supported by local residents can be established by securing such basic data of major tributaries in the Nakdong river system. In this study, the fluctuation characteristics of upstream and downstream water pollution levels were compared using the measurement results of the water environment measurement network and the tributary monitoring project for the gyeseong-stream and Hwapo-stream in the Nakdong-miryang watershed. In 2017, when water pollution is the highest, it was confirmed that the annual average rainfall was the lowest. Although the upstream and downstream water quality tendencies of the Gyeseong-stream are similar, the water quality concentrations of the Gyeseong-stream are relatively different. But although the Hwapo stream has various causes of pollution, there was not much difference in the level of pollution between the upper and lower streams. In addition, both rivers need the ability to purify rivers by securing sufficient water for river maintenance, and if the correlation between water quality items can be inferred through continuous monitoring of tributaries where the aspect of water quality change is unclear, water quality management Determined to be efficient operation.

• 한국물환경학회지
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• 제22권5호
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• pp.943-951
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• 2006

Spatial distribution of water pollution in the Gap Stream was investigated from October to November, 2005. Sampling was conducted three times including effluents discharged from a wastewater treatment plant (WWTP) and a dam reservoir during the low-flow period. As a typical urban stream, total nitrogen and inorganic nitrogen concentrations increased toward downstream. Ammonia concentration was the highest in the treated water of the wastewater treatment plant and the lowest nitrate concentration was found in the effluent of the dam reservoir. A part of soluble reactive phosphorous (SRP) in total phosphorous was 22~54% in the upstream reach of WWTP in the Gap Stream whereas 68~73% in the downstream reach. Mean chlorophyll-a concentration ranged from 1.6 to $11.0{\mu}g/L$ and it tends to increase toward downstream except for WWTP effluent. As expected, untreated wastewater and WWTP effluent were suggested as the major sources of water pollution in the Gap Stream. In this study, the water pollution of the Gap Stream is a significant undergoing typical eutrophication, caused by excessive phosphorus and nitrogen nutrients from WWTP located in the watershed. As a result, the critical factor for the water pollution was evaluated to dissolved inorganic nitrogen and phosphorus nutrients. Particularly, SRP is a most important for the eutrophication. It suggest that may occur in the most urban streams of Korean peninsula. Therefore, because the necessity of water pollution management in the urban stream, inorganic N and P nutrients should be included as an essential component of water quality criteria in the advanced water quality project of Korean Government by enforcing of water quality assessment and total maximum daily loads (TMDLs).

• 한국정보통신학회논문지
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• 제11권8호
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• pp.1519-1527
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• 2007

센서 네트워크에서는 다양하고 폭 넓은 응용 프로그램을 위해서 경제적으로 실행 가능한 모니터링 솔루션을 제공한다. 대부분의 연구에서는 값싼 노드들을 겨냥해서 연구가 진행된다. 센서 네트워크들이 노출되는 보안위협들과 맞서기 위해서, 암호 프로토콜은 센서 노드들 사이에서 점대점 암호화 방식으로 암호화를 실행한다. 알려진 파괴와 속임 위협들은 전송시에 데이터를 암호화 하는 것과 동시에 데이터 소스를 인증하는 것에 의해서 막을 수 있다. 제한된 자원을 가진 노드들에서 저 전력 장치들에게 효과적이라고 알려진 대칭키 알고리즘이 사용된다. 데이터보호는 Dragon Stream Cipher 대칭키 암호화와 새롭게 디자인된 Dragon-MAC Message Authentication Code를 짜 넣는 것에 의한 방법에 의해서 완전하게 된다. 제안된 알고리즘은 MAC 알고리즘에 의해서 요구되는 동작 계산값을 최소화 하기 위한 목적으로써 Dragon Stream Cipher을 기초로 한 계산된 몇몇의 데이터를 사용하기 위해서 디자인 되었다. 빠른 키 스트림 생성을 가진 문자 기반의 Stream Cipher 인 Dragon을 목표로 하여, 한정된 환경에 적합하다. 무선센서 노드에서 권한 암호화의 이행을 통한 실제 인증과 메시지 인증을 겨냥해서 우리의 프로토콜은 계획되었다.

• 농업과학연구
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• 제45권3호
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• pp.521-532
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• 2018

In recent decades, the dry stream phenomena of small and medium sized rivers have been attracting much attention as an important social problem. To prevent dry stream phenomena, it is necessary to build an infrastructure that manages rivers. To accurately determine the progress of dry stream phenomena, it is necessary to continuously measure the discharge and other hydrological factors for small and medium sized rivers. However, until now, the flow data for small and medium rivers in Korea has been insufficient. To overcome the lack of supporting data for supporting rational decision-making in policy and project implementation, a short- and long-term hydrological model was developed that takes into consideration hydrological changes such as the increase of the impervious area due to urban development and groundwater pumping, the construction of a large-scale sewage treatment plant, the maintenance of stream-oriented rivers, etc. In the developed model, the distributed grid is represented by three layers: Surface flow, interflow, and groundwater flow. The surface flow and intermediate flow flowed along the flow direction, and the groundwater flow was calculated by a two-dimensional groundwater analysis model such that the outflow occurred in all directions without a specific flow direction. The effects of land use and cover on evapotranspiration and infiltration and the effects of multiple landscapes can be simulated in the developed model.