• Proceedings of the Korean Information Science Society Conference
• /
• 2010.06c
• /
• pp.423-428
• /
• 2010

최근에는 사회구조가 복잡해 짐에 따라 각 분야의 전문성이 두드러지고 있다. 이러한 흐름은 음식점에도 영향을 주어 기존의 형식에서 벗어난 자신들만의 독특하고 차별성 있는 요리 메뉴의 개발을 가속화시켰다. 그로 인해 한식, 중식, 양식으로 구분하는 전통적인 음식점 분류 방식이 한계를 보였고, 기존의 분류를 포함하면서도 새로이 등장하는 음식점들을 다룰 수 있는 방식이 필요하다. 본 논문에서는 최근 폭발적으로 늘어나는 음식점 추천 웹 사이트의 데이터를 토대로 자동적으로 음식점 분류를 수행하는 방법을 제안한다. 본 연구에서는 각 음식점이 갖고 있는 특징을 메뉴 정보를 통해 파악하려 하였다. 음식점 사이트에서 수집한 2 천개의 음식점, 6 만개의 메뉴 정보를 미리 정의된 필터로 정제한 후 Sequential Information Bottleneck Clustering 알고리즘을 적용하여 구분해 보았다. 실험결과 제안한 방법이 다른 Clustering 방법에 비해 높은 성능을 보였으며 음식점주가 수동적으로 음식점 분류를 입력하는 수고를 줄일 수 있는 가능성을 보였다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.40 no.9
• /
• pp.1725-1727
• /
• 2015

In this letter, a QR decomposition based sequential BP detection scheme is proposed for MIMO systems. The proposed scheme performs the sequential updates from the observation node having the smallest degree among all the observation nodes. Our simulation results verify that the proposed scheme achieves an improved error performance with a significantly accelerated detection convergence speed compared to the conventional schemes.

• The Korean Journal of Applied Statistics
• /
• v.10 no.2
• /
• pp.353-366
• /
• 1997

In this paper, we derive an approximate optimal Bayes group sequential design for a given loss function. We use the Monte-Carlo method to compare the ASN(average sample size) function and Bayes risk of approximate optimal Bayes group sequential design, Pocock design and O'Brien and Fleming design. Also introduced is the concept of Bayes efficiency and percentage loss of information due to grouping for the group sequential design and use it to measure the loss of information for different group sizes.

• Journal of information and communication convergence engineering
• /
• v.9 no.2
• /
• pp.224-229
• /
• 2011

Cellular Automata is a discrete dynamical system that can be completely described in terms of local relation. For any given image, the system can save its features as well as increase or decrease the brightness of it locally through consideration of optimized transition in succession. These transitions in succession satisfy the function "Lyapunov" and have sequential movements. This study suggests the way of noise reduction for each image with the use of the Sequential Cellular Automata system. The mentioned transition in succession gives stable results with high-convergence performance to random noises and PSNR (Peak Signal-to-Noise Ratio) using histograms and MSE (Mean Square Error) for verification of effectiveness.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.11 no.3
• /
• pp.1393-1405
• /
• 2017

It is well known that duty-cycling control by dynamically adjusting the polling interval according to the traffic loads can effectively achieve power saving in wireless sensor networks. Thus, there has been a significant research effort in developing polling interval adaptation schemes. Especially, Dynamic Low Power Listening (DLPL) scheme is one of the most widely adopted open-looping polling interval adaptation techniques in wireless sensor networks. In DLPL scheme, if consecutive idle (busy) samplings reach a given fixed threshold, the polling interval is increased (decreased). However, due to the trial-and-error based approach, it may significantly deteriorate the system performance depending on given threshold parameters. In this paper, we propose a novel DLPL scheme, called SDL (Sequential hypothesis testing based Dynamic LPL), which employs sequential hypothesis testing to decide whether to change the polling interval conforming to various traffic conditions. Simulation results show that SDL achieves substantial power saving over state-of-the-art DLPL schemes.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2014.11a
• /
• pp.771-774
• /
• 2014

지난 몇 년간 스마트폰은 굉장히 빠른 속도로 발전하면서 생활 속에서 큰 비중을 차지하고 있다. 이러한 스마트폰에는 에너지 효율, 크기, 속도 면에서 모바일 기기에 적합한 Flash storage가 탑재되고 있다. 이 논문에서는 스마트폰에 탑재된 Flash storage를 기반으로 한 버퍼 교체 알고리즘들 가운데 Spatial Clock 알고리즘에 초점을 맞추고 있다. 그리고 이 알고리즘이 Video Streaming workload에서 성능 발휘를 하지 못한다는 점을 해결하기 위해 SWSC(Sequential Write Spatial Clock) 알고리즘을 제안하였다. 이 알고리즘은 dirty 페이지들이 연속적인 경우 sequential write를 수행한다. 따라서 write 수행시간을 줄일 수 있고 결과적으로 Video Streaming workload에서도 좋은 성능을 발휘할 수 있다.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.11 no.11
• /
• pp.2166-2171
• /
• 2007

In this paper, we proposed a Sequential Download System(SDS) to provide high steaming QoS in p2p network. SDS is able to receive a media file simultaneously from multiple source peer by download manager and deal with unexpected leave of source peer. Also It can provide stable streaming services with minimum buffering delay and manage request of other peer by memory map in process of downloading.

• KIEAE Journal
• /
• v.9 no.2
• /
• pp.81-90
• /
• 2009

Relating to grasping sequential landscape characteristics in consideration of the behavioral characteristics of the subject experiencing visual perception, this study was made on the subject of main walking line section for visitors of three treasures of Buddhist temples. Especially, as a method of obtaining data for grasping sequential visual perception landscape, the researcher employed [momentum sequential viewpoint setup] according to [the interval of pointers arbitrarily] and fisheye-lens-camera photography using the obtained omni-directional angle visual perception information. As a result, in terms of viewpoint selection, factors like approach road form, change in circulation axis, change in the ground surface level, appearance of objects, etc. were verified to make effect, and among these, approach road form and circulation axis change turned out to be the greatest influences. In addition, as a result of reviewing the effectiveness via the subjects, for the sake of qualitative evaluation of landscape components using the VR picture image obtained in the process of acquiring omni-directional angle visual perception information, a positive result over certain values was earned in terms of panoramic vision, scene reproduction, three-dimensional perspective, etc. This convinces us of the possibility to activate the qualitative evaluation of omni-directional angle picture information and the study of landscape through it henceforth.

• ETRI Journal
• /
• v.42 no.6
• /
• pp.976-986
• /
• 2020

Internet of Things (IoT) is considered the future network to support wireless communications. To realize an IoT network, sufficient spectrum should be allocated for the rapidly increasing IoT devices. Through cognitive radio, unlicensed IoT devices exploit cooperative spectrum sensing (CSS) to opportunistically access a licensed spectrum without causing harmful interference to licensed primary users (PUs), thereby effectively improving the spectrum utilization. However, an open access cognitive IoT allows abnormal IoT devices to undermine the CSS process. Herein, we first establish a hard-combining attack model according to the malicious behavior of falsifying sensing data. Subsequently, we propose a weighted sequential hypothesis test (WSHT) to increase the PU detection accuracy and decrease the sampling number, which comprises the data transmission status-trust evaluation mechanism, sensing data availability, and sequential hypothesis test. Finally, simulation results show that when various attacks are encountered, the requirements of the WSHT are less than those of the conventional WSHT for a better detection performance.

• 한국ITS학회:학술대회논문집
• /
• 2005.11a
• /
• pp.62-66
• /
• 2005