• 한국멀티미디어학회논문지
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• 제20권8호
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• pp.1357-1368
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• 2017

Sensor networks are used in various fields such as marine, defense, and smart home etc. Among the components of the sensor network, the sensor node collects sensor data, as one of the representative sensor network roles, and the sensor node makes a greate influence on the overall performance of the sensor network. Therefore, how to design the sensor node is an important issue in the sensor network field. However, the research on the sensor network architecture suitable for the sensor network installation environment has been made more important than the research on how to configure the sensor node. In this paper, we propose to identify elements to be considered for designing a sensor node that makes a large influence on the performance of the sensor network, and to easily implement the sensor node through the state transition model based on these elements.

• 전기학회논문지P
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• 제64권3호
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• pp.187-192
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• 2015

Detecting human in images is a challenging task owing to their variable appearance and the wide range of poses the they can adopt. The first need is a robust feature set that allows the human form to be discriminated cleanly, even in cluttered background under difficult illumination. A large number of vision application rely on matching keypoints across images. These days, the deployment of vision algorithms on smart phones and embedded device with low memory and computation complexity has even upped the ante: the goal is to make descriptors faster compute, more compact while remaining robust scale, rotation and noise. In this paper we focus on improving the speed of pedestrian(walking person) detection using Histogram of Oriented Gradient(HOG) descriptors provide excellent performance and tracking using kalman filter.

• IEIE Transactions on Smart Processing and Computing
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• 제3권4호
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• pp.167-172
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• 2014

In this paper we propose a waveform design algorithm that localizes the maximum output power in the target direction. We extend existing monostatic radar optimal waveform design schemes to bistatic multiple-input multiple-output (MIMO) radar systems. The algorithm simultaneously calculates the direction of departure (DoD) and the direction of arrival (DoA) using a two-dimensional multiple signal classification (MUSIC) method, and successfully localizes the maximum transmitted power to the target locations by exploiting the calculated DoD. The simulation results confirm the performance of the proposed algorithm.

• 전자공학회논문지SC
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• 제49권3호
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• pp.75-81
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• 2012

최근에 소개된 능동 FSS(active frequency selective surface) 또는 ESS(electromagnetic smart screen)는 2차원 금속섬유 복합재료에서 금속섬유의 부하저항을 변화시킴으로써 복합재료의 분산특성을 변경시키는 기술이다. 본 논문에서는 부하저항의 변화에 따른 ESS의 분산특성을 효율적으로 계산하기 위해 GEC(generalized equivalent conductor) 기법을 기반으로 수정하여 적용한다. 부하저항에 따른 ESS의 투과계수와 유효유전율을 1~40 GHz의 범위에서 시뮬레이션 한다. 또한, 부하저항을 변경함으로써 공진주파수와 대역폭을 변경할 수 있음을 보인다.

• Smart Structures and Systems
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• 제11권2호
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• pp.185-197
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• 2013

We developed a simultaneous strain measurement and damage detection technique using a pair of surface-mounted piezoelectric transducers and a fiber connecting them. This is a novel sensor configuration of the fiber acoustic wave (FAW) piezoelectric transducer. In this study, lead-zirconate-titanate (PZT) transducers are installed conventionally on a plate's surface, which is a technique used in many structural health monitoring studies. However, our PZTs are also connected with an optical fiber. A FAW and Lamb wave are simultaneously guided in the optical fiber and the structure, respectively. The dependency of the time-of-flight of the FAW on the applied strain is quantified for strain sensing. In our experimental results, the FAW exhibited excellent linear behavior and no hysteresis with respect to the change in strain. On the other hand, the well-known damage detection function of the surface-mounted PZT transducers was still available by monitoring the waveform change in the conventional Lamb wave ultrasonic path.

• 디지털산업정보학회논문지
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• 제12권1호
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• pp.97-106
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• 2016

3D virual reality technique develop rapidly such as parts of education, health, national defense, etc. This paper implements an education contents utilizing 3D virtual reality based on HMD. In this paper, contents make up Changdeokgung Palace using to 3Dmax and Unity program, it shows on implemented Helmet Mounted Display. HMD obtain dynamic image from the target source of smart phone. Also, contents consist of service senerio through divided palace position and King's a day's journey especially. Above all, this paper indicate improving performance according to reduced cybersickness and immersion enlargement. And memory capacity reduced by various technique such that file type, compressed file, minimized resource. Proposed technique can obtain dynamic 3D image by HMD implementation at real time basis so that it is possible to use simultaneously multi-source. From the various and practical experiment, it is confirm that proposed 3D VR education system is useful for experience of virtual reality practically.

• 정보보호학회지
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• 제20권2호
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• pp.51-55
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• 2010

오늘날 안티바이러스 분야는 다양한 도전에 직면해 있다. 악성코드의 수 자체가 급격히 증가하고 있고, 첨단 기술로 무장하여 루트킷 등으로 자신을 은폐하기도 하며, 널리 사용되는 애플리케이션의 취약점을 이용하여 칩입하고, 보안 프로그램의 동작을 방해하기 까지 한다. 이런 상황에서 클라우드 컴퓨팅은 악성코드에 대응함에 있어 새로운 패러다임을 가져왔다. 그 결과 폭발적으로 증가하는 악성코드의 수에 효과적으로 대응할 수 있게 되었다. 뿐만 아니라 샘플과 위협 정보 수집 방식의 변화와 악성코드 분석 방식의 변혁이 이루어졌다. 이를 기반으로 의심 파일의 신고와 수집을 자동화하고 다각도로 분석하여 위협에 대응하는 것이 실시간으로 이루어 질 수 있게 되었다. 본 논문에서는 안철수연구소의 클라우드 기반 보안 서비스인 AhnLab Smart Defense(이하 ASD)의 사례를 통하여 클라우드 컴퓨팅 기반의 악성코드 대응 방법을 살펴본다.

• 한국정보전자통신기술학회논문지
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• 제7권4호
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• pp.159-167
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• 2014

Local device-to-device (D2D) communication between two smart mobile devices is becoming increasingly popular. The first key step in starting a D2D communication is to discover and identify the remote target device to establish a link. However, existing device discovery mechanisms either require users to explicitly identify the ID of the target device or rely on inaccurate beamforming technology. This paper presents two novel device identification algorithms using a variety of embedded sensors. The algorithms only require that users to point two devices towards each other. This paper describes the algorithms, analyzes their accuracy using analytical models, and verifies the results using simulations.

• 디지털산업정보학회논문지
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• 제8권3호
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• pp.49-55
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• 2012

Recently, with the rapid development of android-based smartphones, it is becomes a major security issue that the case of Android platform is an open platform. so it is easy to be a target of mobile virus penetration and hacking. Even there are a variety of security mechanisms to prevent the vulnerable points of the Android platform but the reason of most of the security mechanisms were designed at application-level that highly vulnerable to the attacks directly to the operating system or attacks using the disadvantages of an application's. It is necessary that the complementary of the android platform kernel blocks the kernel vulnerability and the application vulnerability. In this paper, we proposed a secure system using linux-based android kernel applied to LIDS(Linux Intrusion Detection and Defense System) and applied a smart phone with s5pc110 chip. As a result, the unauthorized alteration of the application was prevented with a proposed secure system.

• 반도체디스플레이기술학회지
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• 제21권4호
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• pp.86-91
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• 2022

Cache bypassing is a scheme to prevent unnecessary cache blocks from occupying the capacity of the cache for avoiding cache contamination. This method is introduced to alleviate the problems of non-volatile memories (NVMs)-based memory system. However, the prior works have been studied without considering wear-out attack. Malicious writing to a small area in NVMs leads to the failure of the system due to the limited write endurance of NVMs. This paper proposes a novel scheme to prolong the lifetime with higher resistance for the wear-out attack. First, the memory reference pattern is found by modified reuse distance calculation for each cache block. If a cache block is determined as the target of the attack, it is forwarded to higher level cache or main memory without updating the NVM-based cache. The experimental results show that the write endurance is improved by 14% on average and 36% on maximum.