• The Journal of the Korea institute of electronic communication sciences
• /
• v.5 no.6
• /
• pp.588-594
• /
• 2010

In a multi-hop wireless sensor network, broadcasting is an elementary operation to support command message sending, route discovery and other application tasks. Broadcasting by flooding may cause serious redundancy, contention, and collision in the network, which is referred to as the broadcast storm problem. Many broadcasting schemes have been proposed to give better performance than simple flooding in wireless sensor network. How to decide whether re-broadcast or not also poses a dilemma between reach ability and efficiency under different host densities. In this paper, we present popular broadcasting schemes, which can reduce re-broadcast packets and improve SRB(Saved ReBroadcast). Simulation results show different levels of improvement over the simple flooding scheme.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.5B
• /
• pp.247-256
• /
• 2007

In this paper, we propose Geographical Back-off Routing (Geo-Back Routing) protocol for wireless sensor networks. Geo-Back uses the positions of nodes, a packet's destination and a optimal back-off time to make the packet forwarding decisions using only source and destination's location information without information about neighbor nodes' location or the number of one hop neighbor nodes. Under the frequent topology changes in WSNs, the proposed protocol can find optimal next hop location quickly without broadcast algorithm for update. In our analysis, Geo-Back's scalability and better performance is demonstrated on densely deployed wireless sensor networks.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.41 no.5
• /
• pp.111-116
• /
• 2004

It is essential to know the information about the prior model for wavelet coefficients, the probability distribution of noise, and the variance of wavelet coefficients for noise reduction using Bayesian estimation in wavelet domain. In general denoising methods, the signal variance is estimated from the proper prior model for wavelet coefficients. In this paper, we propose a variable window size decision algorithm to estimate signal variance according to image region. Simulation results shows the proposed method have better PSNRs than those of the state of art denoising methods.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.5C
• /
• pp.487-495
• /
• 2007

When error occurs during the network transmission of the image, the quality of the restored image is very serious. Therefore to maintain the received image quality, the error concealment technique is necessary. This paper presents an efficient spatial error concealment method using adaptive edge-oriented interpolation. It deals with errors on slice level. The proposed method uses boundary matching method having 2-step processes. We divide error block into external and internal region, adaptively restore each region. Because this method use overall as well as local edge characteristics, it preserves edge continuity and texture feature. The proposed technique reduces the complexity and provide better reconstruction quality for damaged images than the previous methods.

• 건강소식
• /
• v.16 no.10 s.167
• /
• pp.2-5
• /
• 1992

날로 각박해져가는 사회분위기 속에서 가장 외로움을 많이 느끼는 사람들은 역시 불우한 환경에 처한 사람들, 특히 사회복지시설에 수용되어 있는 사람들일 것이다. 이들에게는 산다는 것, 생활한다는 것 자체가 커다란 짐일 수 밖에 없다. 이런 상황 속에서, 인간에게 가장 중요하다고 할 수 있는 "건강문제"는 부차적인 것으로 밀려나게 마련이다. 이처럼, 어려운 시대를 함께 살고있는 불우한 이웃을 위해 한국건강관리협회 대구지부가 사회복지시설 수용자의 건강관리를 위한 무료검진을 실시해 눈길을 모은다. 지난 7월말부터 8월초까지 실시된 무료순회검진을 통해 1천여명의 대구시내시설 아동ㆍ노인들이 검사를 받았고, 대구지부는 앞으로도 이같은 사회복지사업을 계속 펴나갈 계획이라고 밝혔다.

• The Bimonthly Magazine for Agrochemicals and Plant Protection
• /
• v.6 no.2
• /
• pp.79-88
• /
• 1985

쌀자급을 위한 다수확재배 방법을 도입함으로서 병해충의 발생양상도 변모하고 있다. 병해충 발생 상황을 정확하게 파악하여 방제에 대처해 나간다면 병충해로 인한 피해를 최소화 할 수 있을 것이다. 다행히 병충해로 인한 피해가 점차 적어지고 있으며 이웃 일본보다도 해에 따라서는 앞서고 있어 우리 농민들의 방제기술 수준이 높아졌음을 증명하고 있는 것이다. 병충해로 인한 피해는 앞집무늬마름병과 도열병$\cdot$멸구류가 주종을 이루고 있다. 도열병과 멸구류 피해는 해에 따라 큰 차이가 있으며 앞집무늬마름병은 넓게 발생되어 피해를 주고 있는 것이 특징이라 하겠다. 주요 병충별 발생동향과 금년도 방제초점이 무엇인가 살펴보기로 한다.

• Water for future
• /
• v.33 no.5
• /
• pp.49-55
• /
• 2000

전통적인 매개변수적 목적함수 추정방법은 관측자료의 모든 영역에 걸쳐 선형 또는 지수함수 형태의 가정을 기본으로 매개변수를 추정하는 반면 비매개 변수적 Kernel 가중함수를 이용한 방법은 목적함수의 형태에 대한 가정이 필요 없이 관심 있는 임의의 추정지점에서 이웃하는 자료를 이용하여 목적함수를 국지적으로 근사하는 방법이다. 추계학적 수문학의 전형적인 문제인 "목적함수의 가정"에 의해 발생되는 문제를 줄이려는 노력의 일환으로 비매개변수적 Kernel 가중함수를 이용하는 방법에 연구되었고, 본 지면에서는 Kernel 가중함수를 이용한 비매개변수적 확률밀도함수의 기본이론과 빈도해석, 회귀모형 및 비동질성 천이확률 등의 수문학적 응용에 대하여 살펴보았다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2022.11a
• /
• pp.236-238
• /
• 2022

선박의 접/이안 및 협수로 운항은 사고 위험성이 가장 높은 과정 중에 하나로, 많은 이해관계자들의 협업으로 진행된다. 하지만 날로 복잡해져가는 연안 지역에서, 접/이안 및 협수로 운항에서 가장 필요한 정보인 이웃 지형과의 거리 및 주변 선박과의 거리 정보 등을 대부분 목측에 의존하고 있어 이해관계자들 간의 정보 차이 또는 부주의로 인해 사고 위험성이 높아지고 있다. 이러한 문제를 해결하기 위해, 객체 인식 및 센서 융합 기반의 3차원 어라운드 뷰 도선지원 시스템을 개발하고자 하고 총 5년의 개발 계획에서 2차년도까지의 개발 내용을 소개하고자 한다..

• Cartoon and Animation Studies
• /
• s.40
• /
• pp.211-242
• /
• 2015

Recently, the shrunk influence of printed cartoon has been superseded by the influence of Webtoon in the comic industry. Webtoon has gained popularity and interest by being served on internet quickly and easily. Their novel material and sympathetic topic have made it possible for many Webtoons to be reproduced into tv dramas and movies, so, the influence of them has been increased as the copyright industry of culture contents industry. The increasing interest for Webtoon has induced academic studies for the subject. Among the various studies in need on Webtoon, the most important study topics in need are 'Story' and 'Quality' which are criterion for readers to choose Webtoons to read. To create the Webtoon that are great at 'Story' and 'Quality', the study on plots should be preceded, which recast episodes organically through a logical causal relationship. Therefore, in this study, the plots of Webtoons have been analyzed through Rescue plot in and the Riddle plot in selected from the Kang Full's Webtoon series, 'mystery psychology horror season', which are evaluated as the great work at 'Story' and 'Quality.' The analysis was implemented based on Tobias' theory which suggests 'the characteristics of plot' and '8 principles for good plot.' First, Kang Full's webtoons were analyzed through 'the characteristics of plot' and '6 principles for good plot' which is modified from '8 principles of good plot' based on Tobias' theory. Applicability was checked if Tobias' theory could be applied to Kang Full's Webtoon checking through the scenes and contents of the Webtoon. (1) Tobias' 'the characteristics of plot' could be applied to both Rescue plot in and the Riddle plot in . (2) Among '6 principles for good plot', 5 principles are shown in The Lighting Store and all of the 6 principles in Neighbor. The result shows that Tobias theory could be applied to the plot of Webtoon. The fact that Kang Full's Webtoons are composed in a formulaic form could be identified through 'the characteristics of plot' and '6 principles for good plot' shown in Rescue plot in and the Riddle plot in .

• 전자공학회논문지 IE
• /
• v.47 no.2
• /
• pp.60-65
• /
• 2010

In this paper, we propose a dual-band filtering method optimized to DBO-CSS systems which are alternatively transmitted in low and high bands. The conventional channel filter which passes entire signal bandwidth causes a problem that excessive noise in neighboring sub-band is added while one of signals in two sub-bands is received. The dual-band filtering proposed in this paper can overcome the performance degradation in the conventional filtering method without increase of hardware complexity. The proposed method is based on two filters to be matched with DBO-CSS signals receiving alternatively and can exclude the undesired noise in neighboring sub-band. Simulation results for the proposed method show better performance about 2.5dB than the conventional one.