3D Navigation Real Time RSSI-based Indoor Tracking Application

Lee, Boon-Giin,Lee, Young-Sook,Chung, Wan-Young The Institute of Electronics and Information Engin 2008 JUCT : Journal of Ubiquitous Convergence Technolog Vol.2 No.2

Representation of various types of information in an interactive virtual reality environment on mobile devices had been an attractive and valuable research in this new era. Our main focus is presenting spatial indoor location sensing information in 3D perception in mind to replace the traditional 2D floor map using handheld PDA. Designation of 3D virtual reality by Virtual Reality Modeling Language (VRML) demonstrates its powerful ability in providing lots of useful positioning information for PDA user in real-time situation. Furthermore, by interpolating portal culling algorithm would reduce the 3D graphics rendering time on low power processing PDA significantly. By fully utilizing the CC2420 chipbased sensor nodes, wireless sensor network was established to locate user position based on Received Signal Strength Indication (RSSI) signals. Implementation of RSSI-based indoor tracking method is low-cost solution. However, due to signal diffraction, shadowing and multipath fading, high accuracy of sensing information is unable to obtain even though with sophisticated indoor estimation methods. Therefore, low complexity and flexible accuracy refinement algorithm was proposed to obtain high precision indoor sensing information. User indoor position is updated synchronously in virtual reality to real physical world. Moreover, assignment of magnetic compass could provide dynamic orientation information of user current viewpoint in real-time.

Extended Information Overlap Measure Algorithm for Neighbor Vehicle Localization

Punithan, Xavier,Seo, Seung-Woo The Institute of Electronics and Information Engin 2013 IEIE Transactions on Smart Processing & Computing Vol.2 No.4

Early iterations of the existing Global Positioning System (GPS)-based or radio lateration technique-based vehicle localization algorithms suffer from flip ambiguities, forged relative location information and location information exchange overhead, which affect the subsequent iterations. This, in turn, results in an erroneous neighbor-vehicle map. This paper proposes an extended information overlap measure (EIOM) algorithm to reduce the flip error rates by exchanging the neighbor-vehicle presence features in binary information. This algorithm shifts and associates three pieces of information in the Moore neighborhood format: 1) feature information of the neighboring vehicles from a vision-based environment sensor system; 2) cardinal locations of the neighboring vehicles in its Moore neighborhood; and 3) identification information (MAC/IP addresses). Simulations were conducted for multi-lane highway scenarios to compare the proposed algorithm with the existing algorithm. The results showed that the flip error rates were reduced by up to 50%.

Ranking Quality Evaluation of PageRank Variations

팜민득,허준석,이정훈,황규영,Pham, Minh-Duc,Heo, Jun-Seok,Lee, Jeong-Hoon,Whang, Kyu-Young The Institute of Electronics and Information Engin 2009 電子工學會論文誌-CI (Computer and Information) Vol.38 No.10

The PageRank algorithm is an important component for ranking Web pages in Google and other search engines. While many improvements for the original PageRank algorithm have been proposed, it is unclear which variations (and their combinations) provide the "best" ranked results. In this paper, we evaluate the ranking quality of the well-known variations of the original PageRank algorithm and their combinations. In order to do this, we first classify the variations into link-based approaches, which exploit the link structure of the Web, and knowledge-based approaches, which exploit the semantics of the Web. We then propose algorithms that combine the ranking algorithms in these two approaches and implement both the variations and their combinations. For our evaluation, we perform extensive experiments using a real data set of one million Web pages. Through the experiments, we find the algorithms that provide the best ranked results from either the variations or their combinations. PageRank 알고리즘은 구글(Google)등의 검색 엔진에서 웹 페이지의 순위(rank)를 정하는 중요한 요소이다. PageRank 알고리즘의 순위 품질(ranking quality)을 향상시키기 위해 많은 변형 알고리즘들이 제안되었지만 어떤 변형 알고리즘(혹은 변형 알고리즘들간의 조합)이 가장 좋은 순위 품질을 제공하는지가 명확하지 않다. 본 논문에서는 PageRank 알고리즘의 잘 알려진 변형 알고리즘들과 그들 간의 조합들에 대해 순위 품질을 평가한다. 이를 위해, 먼저 변형 알고리즘들을 웹의 링크(link) 구조를 이용하는 링크기반 방법(Link-based approaches)과 웹의 의미 정보를 이용하는 지식기반 방법(Knowledge-based approaches)으로 분류한다. 다음으로, 이 두 가지 방법에 속하는 알고리즘들을 조합한 알고리즘들을 제안하고, 변형 알고리즘들과 그들을 조합한 알고리즘들을 구현한다. 백만 개의 웹 페이지들로 구성된 실제 데이터에 대한 실험을 통해 PageRank의 변형 알고리즘들과 그들 간의 조합들로부터 가장 좋은 순위 품질을 제공하는 알고리즘을 찾는다.

Fuzzy Logic-based Context-Aware Access Control Model for the Cloud Computing Environment

징스다,정목동,Jing, Si Da,Chung, Mok-Dong The Institute of Electronics and Information Engin 2011 전자공학회논문지CI (Computer and Information) Vol.41 No.2

무선 환경에서의 인증 모델은 많은 보안 위험을 내포하고 있다. 그러나 이 분야에 일반적으로 사용되는 표준 기술이 존재하는 것이 아니어서 본 논문에서는 무선 인증 환경에서 보다 강화된 보안을 제시할 수 있는 퍼지 논리 기반의 인증 모델을 제시한다. 제안하는 모델을 위해서 퍼지 논리 기반의 분류 방법을 사용하고 적절한 판단을 위해서 개선된AHP 알고리즘과 사례 기반의 추론 방법을 추가적으로 사용한다. 개선된AHP 알고리즘을 사용해서 다양한 상황정보를 수치화하고, 제안된 인증 모델을 사용해서 입력 데이터에 대한 보안 등급을 계산한 다음, 다양한 환경의 상황정보를 가진 무선환경에 제안된 인증 모델을 안정적으로 사용할 수 있을 것이다. 향후에는 상황인식 연구를 클라우드 컴퓨팅 분야를 포함한 다양한 분야로 제안 모델을 확대하면 더욱 안전한 보안 환경을 기대할 수 있을 것이다. Authentication model in the wireless environment has many security vulnerabilities. However, there is no adapting standard method in this field. Therefore, we propose a fuzzy logic based authentication model to enhance the security level in the authentication environment. We use fuzzy logic based classification to construct our model, and also additionally utilize improved AHP and case-based reasoning for an appropriate decision making. We compute the context information by using the improved AHP method, use the proposed model to compute the security level for the input data, and securely apply the proposed model to the wireless environment which has diverse context information. We look forward to better security model including cloud computing by extending the proposed method in the future.

Natural-Language-Based Robot Action Control Using a Hierarchical Behavior Model

Ahn, Hyunsik,Ko, Hyun-Bum The Institute of Electronics and Information Engin 2012 IEIE Transactions on Smart Processing & Computing Vol.1 No.3

In order for humans and robots to interact in daily life, robots need to understand human speech and link it to their actions. This paper proposes a hierarchical behavior model for robot action control using natural language commands. The model, which consists of episodes, primitive actions and atomic functions, uses a sentential cognitive system that includes multiple modules for perception, action, reasoning and memory. Human speech commands are translated to sentences with a natural language processor that are syntactically parsed. A semantic parsing procedure was applied to human speech by analyzing the verbs and phrases of the sentences and linking them to the cognitive information. The cognitive system performed according to the hierarchical behavior model, which consists of episodes, primitive actions and atomic functions, which are implemented in the system. In the experiments, a possible episode, "Water the pot," was tested and its feasibility was evaluated.

RF Dispersion and Linearity Characteristics of AlGaN/InGaN/GaN HEMTs

Lee, Jong-Uk The Institute of Electronics and Information Engin 2004 電子工學會論文誌-CI (Computer and Information) Vol.41 No.11

본 논문에서는 molecular beam epitaxy (MBE)로 성장한 AlGaN/InGaN/GaN high electron-mobility transistors (HEMTs)의 선형성과 RF dispersion 특성을 조사하였다. 전극 길이가 0.5 ㎛인 AlGaN/InGaN HEMT는 최대 전류 밀도가 730mA/mm, 최대 전달정수가 156 mS/mm인 비교적 우수한 DC 특성과 함께, 기존의 AlGaN/GaN HEMT와는 달리 높은 게이트 전압에도 완만한 전류 전달 특성을 보여 선형성이 우수함을 나타내었다. 또한 여러 다른 온도에서 측정한 펄스 전류 특성에서 소자 표면에 존재하는 트랩에 의한 전류 와해 (current collapse) 현상이 발생되지 않음을 확인하였다. 이 연구 결과는 InGaN를 채널층으로 하는 GaN HEMT의 경우 선형성이 우수하고, 고전압 RF 동작조건에서 출력저하가 발생하지 않는 고출력 소자를 제작할 수 있음을 보여준다. This paper reports the RF dispersion and linearity characteristics of unpassivated AlGaN/InGaN/GaN high electron-mobility transistors (HEMTs) grown by molecular beam epitaxy (MBE). The devices with a 0.5 ${\mu}{\textrm}{m}$ gate-length exhibited relatively good DC characteristics with a maximum drain current of 730 mA/mm and a peak g$_{m}$ of 156 mS/mm. Highly linear characteristic was observed by relatively flat DC transconductance (g$_{m}$) and good inter-modulation distortion characteristics, which indicates tight channel carrier confinement of the InGaN channel. Little current collapse in pulse I-V and load-pull measurements was observed at elevated temperatures and a relatively high power density of 1.8 W/mm was obtained at 2 GHz. These results indicate that current collapse related with surface states will not be a power limiting factor for the AlGaN/InGaN HEMTs.

Mechanism and Application of NMOS Leakage with Intra-Well Isolation Breakdown by Voltage Contrast Detection

Chen, Hunglin,Fan, Rongwei,Lou, Hsiaochi,Kuo, Mingsheng,Huang, Yiping The Institute of Electronics and Information Engin 2013 Journal of semiconductor technology and science Vol.13 No.4

An innovative application of voltage-contrast (VC) inspection allowed inline detection of NMOS leakage in dense SRAM cells is presented. Cell sizes of SRAM are continual to do the shrinkage with bit density promotion as semiconductor technology advanced, but the resulting challenges include not only development of smaller-scale devices, but also intra-devices isolation. The NMOS leakage caused by the underneath n+/P-well shorted to the adjacent PMOS/N-well was inspected by the proposed electron-beam (e-beam) scan in which VC images were compared during the in-line process step of post contact tungsten (W) CMP (Chemical Mechanical Planarization) instead of end-of-line electrical test, which has a long response time. A series of experiments based on the mechanism for improving the intra-well isolation was performed and verified by the inline VC inspection. An optimal process-integration condition involved to the tradeoff between the implant dosage and photo CD was carried out.

Tracking Algorithm Based on Moving Slide Window for Manuevering Target

배진호,이종현,전형구,Bae, Jinho,Lee, Chong Hyun,Jeon, Hyoung-Goo The Institute of Electronics and Information Engin 2016 전자공학회논문지 Vol.53 No.4

In this paper, we propose a novel tracking algorithm called slide window tracker (SWT) suitable for maneuvering target. To efficiently estimate trajectory of moving target, we adopt a sliding piecewise linear window which includes past trace information. By adjusting the window parameters, the proposed algorithm is to reduce measurement noise and to track fast maneuvering target with little computational increment as compared to ${\alpha}-{\beta}$ tracker. Throughout the computer simulations, we verify outstanding tracking performance of the SWT algorithm in noisy linear and nonlinear trajectories. Also, we show that the SWT algorithm is not sensitive to initial model parameter selection, which gives large degree of freedom in applying the SWT algorithm to unknown time-varying measurement environments.

VR, AR Simulation and 3D Printing for Shoulder and Elbow Practice

임원봉,문영래,Lim, Wonbong,Moon, Young Lae The Institute of Electronics and Information Engin 2016 전자공학회논문지 Vol.53 No.12

Recent advances in technology of medical image have made surgical simulation that is helpful to diagnosis, operation plan, or education. Improving and enhancing the medical imaging have led to the availability of high definition images and three-dimensional (3D) visualization, it allows a better understanding in the surgical and educational field. The Real human field of view is stereoscopic. Therefore, with just 2D images, stereoscopic reconstruction process through the surgeon's head, is necessary. To reduce these process, 3D images have been used. 3D images enhanced 3D visualization, it provides significantly shorter time for surgeon for judgment in complex situations. Based on 3D image data set, virtual medical simulations, such as virtual endoscopy, surgical planning, and real-time interaction, have become possible. This article describes principles and recent applications of newer imaging techniques and special attention is directed towards medical 3D reconstruction techniques. Recent advances in technology of CT, MR and other imaging modalities has resulted in exciting new solutions and possibilities of shoulder imaging. Especially, three-dimensional (3D) images derived from medical devices provides advanced information. This presentation describes the principles and potential applications of 3D imaging techniques, simulation and printing in shoulder and elbow practice.

Study on the Thermal Transient Response of TSV Considering the Effect of Electronic-Thermal Coupling

Li, Chunquan,Zou, Meng-Qiang,Shang, Yuling,Zhang, Ming The Institute of Electronics and Information Engin 2015 Journal of semiconductor technology and science Vol.15 No.3

The transmission performance of TSV considering the effect of electronic-thermal coupling is an new challenge in three dimension integrated circuit. This paper presents the thermal equivalent circuit (TEC) model of the TSV, and discussed the thermal equivalent parameters for TSV. Si layer is equivalent to transmission line according to its thermal characteristic. Thermal transient response (TTR) of TSV considering electronic-thermal coupling effects are proposed, iteration flow electronic-thermal coupling for TSV is analyzed. Furthermore, the influences of TTR are investigated with the non-coupling and considering coupling for TSV. Finally, the relationship among temperature, thickness of $SiO_2$, radius of via and frequency of excitation source are addressed, which are verified by the simulation.