Classification and Experimental Analysis for Clone Detection Approaches in Wireless Sensor Networks

Kwantae Cho,Minho Jo,Taekyoung Kwon,Hsiao-Hwa Chen,Dong Hoon Lee IEEE 2013 IEEE systems journal Vol.7 No.1

<P>Wireless sensor networks (WSNs) consist of tiny sensor nodes that communicate with each other over wireless channels, often in a hostile environment where nodes can be captured and compromised. Consequently, an adversary may launch a clone attack by replicating the captured nodes to enlarge the compromised areas employing clones. Thus, it is critical to detect clone nodes promptly for minimizing their damage to WSNs. Recently, various clone detection schemes were proposed for WSNs, considering different types of network configurations, such as device types and deployment strategies. In order to choose an effective clone detection scheme for a given sensor network, the selection criteria play an important role. In this paper, we first investigate the selection criteria of clone detection schemes with regard to device types, detection methodologies, deployment strategies, and detection ranges. We then classify the existing schemes according to the proposed criteria. Simulation experiments are conducted to compare their performances. It is concluded that it is beneficial to utilize the grid deployment knowledge for static sensor networks; the scheme using the grid deployment knowledge can save energy by up to 94.44% in comparable performance (specifically in terms of clone detection ratio and the completion time), as compared to others. On the other hand, for mobile sensor networks, no existing approach works efficiently in reducing detection error rate.</P>

A 55.77 μW Bio-impedance Sensor with 276 μs Settling Time for Portable Blood Pressure Monitoring System

Kwantae Kim,Minseo Kim,Hyunwoo Cho,Kwonjoon Lee,Hoi-Jun Yoo 대한전자공학회 2017 Journal of semiconductor technology and science Vol.17 No.6

An ultra-low power bio-impedance sensor for wrist watch-type blood pressure monitoring system is implemented in 0.18 μm CMOS technology under 1.8 V supply. The duty-cycled current generator (DCG) enables low power and high amplitude current injection with 93.58% power reduction in a current generator block. A fast-settling readout circuit with DC balanced amplifier reduces settling time to 276 μs, allowing bio-impedance signal acquisition even when the motion artifact induced circuit transient occurs. The simulated 2.125 mm² single chip bio-impedance sensor consumes only 55.77 μW.

Effects of Modified Insole on Lower Extremities Biomechanics in College Male Basketball Players

( Kwantae Kim ),( Mi-sun Kim ),( Ki-kwang Lee ),( Hsien-te Peng ) 한국체육학회 2020 International journal of human movement science Vol.14 No.1

The purpose of this study was to investigate the effect of fore-medial-side thin insole on lower extremities kinematics and kinetics in college male basketball players. Seven male college basketball players voluntarily participated in the study (heights= 173.1 ± 3.1 cm; weights= 68.6 ± 5.7 kg; age= 21.1 ± 2.0 yrs.). They wore the same basketball shoes with 2 types of insoles: one type was original insole (OI); another one was fore-medial-side gradually thin insole (TI). Participants were asked to perform L-cut, V-cut, Backdoor-cut, walk, shuttle run of basketball movement in a 5-meter running way with their maximum speed. They were instructed to step with their right leg when they changed direction. The kinematic and kinetic data were collected during support phase. Non-parametric Wilcoxon signed rank test and the effect size were used to determine the difference of the variables of interest between the original and fore-medial-side thin insoles. The fore-medial-side thin insole showed less foot inversion angle at contact, peak ankle lateral shear force and ankle dorsiflexion moment than the original insole in L-cut (p<.05). In V-cut, the fore-medial-side thin insole showed less hip internal rotation at contact than the original insole (p<.05). In the shuttle run, the fore-medial-side thin insole showed less hip abduction at contact than the original insole (p<.05). In case of foot pressure, it showed no statistically significant but had large effect size on left foot’s pressure time integral (PTI), in L-cut (≥0.8), large effect size on left foot’s PCP, PTI, right foot’s PTI in V-cut (≥0.8), large effect size on left foot’s peak contact pressure of 1st metatarsal (PCP), PTI, peak pressure gradient (PPG), right foot’s PTI in BD-cut (≥0.8), large effect size on left foot’s PTI, medium effect size on left foot’s PPG (≥0.5), and medium effect size on left foot’s the distance from the point of peak contact pressure to the medial edge of 1st metatarsal (PCPd) (≥0.5). In conclusion, the fore-medial-side thin insole can help to push our body to the medial side and decrease the risk of injuries of the lower extremity during cutting movements.

Effect of Modified High-heels on Metatarsal Stress in Female Workers

( Kwantae Kim ),( Hsien-te Peng ) 한국운동역학회 2019 한국운동역학회지 Vol.29 No.3

Objective: The purpose of this study was to identify the effect of high-heels (HH) modification on metatarsal stress in female workers. Method: Seven females who work in clothing stores (heights = 160.4±3.9 cm; weights = 47.4±4.1 kg; age = 31.3±11.1 yrs; HH wear career = 8±6.5 yrs) wore two types of HH (original and modified). The modified HH had been grooved with 1.5 cm radius and 0.2 cm depth around the first metatarsal area inside of the shoes using the modified shoe-last. Participants were asked to walk for 15 minutes on a treadmill and to stand for 10 minutes with original and modified HH, respectively. Kinetics data were collected by the F-scan in-shoe system. After each test, participants were asked to rate their perceived exertion using the Borg's 15-grade RPE scale and interviewed about their feeling of HH. Nonparametric Wilcoxon signed-rank test and effect size (Cohen's d) were used to determine the difference of the variables of interest between the original and modified HH. Results: In the present study, modified HH of the peak contact pressure of 1st metatarsal (PCP) left, PCP right, pressure time integral (PTI) left, peak pressure gradient (PPG) left during standing and PPG right during walking are greater than original HH. And even it didn't show statistically significant, the average in all pressure values of modified HH showed bigger than original HH. It surmised to be related to awkward with modified HH. Even though they said to feel the comfortable cause of big space inside of HH in the interview, they seemed to be not enough time to adapt with new HH. So their walking and standing postures were unstable. Conclusion: Modified the fore-medial part of HH can reduce the stress in the first metatarsal head and big toe area during standing and walking.

Energy-efficient replica detection for resource-limited mobile devices in the internet of things

Kwantae Cho,Byung-Gil Lee,Kyungho Lee,Dong Hoon Lee IET 2013 IET COMMUNICATIONS Vol.7 No.18

<P>The forthcoming Internet of Things - an intelligent collaboration of resource-limited static/mobile devices that are embedded in the daily lives of users - poses new challenges to security and end-user privacy. One of the most challenging problems is how to thwart replica attacks. Once a device is captured physically by an attacker or contaminated by malicious code, it can be reprogrammed and the secret information inside can be duplicated into a large number of replicas that maliciously occupy the network and collect users private information without authorisation. In this study, the authors focus on studying the detection of replicas in mobile applications; which can consist of resource-limited static devices attached to mobile entities. Most existing solutions for detecting replicas have been designed for static devices, and cannot be immediately applied to mobile devices because of their unique properties, in particular, their node mobility. The authors present two efficient methods for detecting replicas in mobile devices. Through performance evaluations, they find that the proposed methods provide highly accurate replica detection with nearly zero detection errors. Furthermore, the distributed and cooperative strategy of the methods significantly reduces the energy required to detect replicas while providing faster replica detection than the existing solutions.</P>

Low-Priced and Energy-Efficient Detection of Replicas for Wireless Sensor Networks

Kwantae Cho,Byung-Gil Lee,Dong Hoon Lee IEEE 2014 IEEE transactions on dependable and secure computi Vol.11 No.5

<P>The forthcoming internet of things - an intelligent collaboration of resource-limited devices such as wireless sensor nodes that are embedded in the daily lives of users - poses new challenges to security and end-user privacy. One of the most challenging problems is the thwarting of replica attacks. Once a sensor node is physically captured, it can be reprogrammed and replicated into a large number of replicas, which may maliciously occupy the network. Thus far, various schemes have been proposed to detect replicas; however, most of them require expensive hardware such as a global positioning system. In general, the ideal price for a sensor node is as low as one dollar, and thus, it is equipped with limited resources; hence, it is not practical to employ additional devices. In this paper, we propose a low-priced and efficient solution for replica detection in static wireless sensor networks. Although the proposed solution does not need any additional hardware, it exhibits similar or better performance, as compared to existing schemes. Through simulation experiments, we show that the proposed solution provides comparable performance in terms of the replica detection ratio and the time required to detect replicas. Furthermore, we show that the proposed solution saves more energy than existing schemes in most of our simulations.</P>

Implant-supported fixed restoration of post-traumatic mandibular defect accompanied with skin grafting : a clinical report

Kwantae Noh,Woo-Jin Choi,Ahran Pae 대한치과보철학회 2013 The Journal of Advanced Prosthodontics Vol.5 No.1

Traumatic defects are mostly accompanied by hard and soft tissue loss. This report describes the surgical and prosthetic treatment of a patient with post-traumatic mandibular defect. A split-thickness skin graft was performed prior to implant placement and prefabricated acrylic stent was placed to hold the graft in place. The esthetic and functional demands of the patient were fulfilled by implant-supported screw-retained fixed prosthesis.

애드혹 네트워크에서 안전한 통계정보수집 기법에 관한 연구

조관태 ( Kwantae Cho ),이병길 ( Byung-gil Lee ) 한국정보처리학회 2014 한국정보처리학회 학술대회논문집 Vol.21 No.2

애드혹 네트워크(Ad Hoc Network)는 최근 이슈가 되고 있는 사물 간 인터넷(Internet of Things), 스마트그리드 (Smart Grid), 사람 중심 도시 센싱 (People-Centric Urban Sensing), 해상 통신 (Maritime Communications) 환경에서 다양하게 활용되는 네트워크 구조다. 이러한 환경에서의 애플리케이션들은 사용자들에게 다양한 편의성을 제공하기 위하여 사용자의 민감한 프라이버시 정보를 요구하기도 한다. 하지만,만약 수집되어지는 프라이버시 정보가 인가되지 않은 공격자에게 노출된다면,사용자는 불안함을 호소할 수 있을 것이고,동시에 해당 데이터를 수집하고자 했던 서비스제공자는 경제적으로 커다란 손실을 입을 수 있다. 이러한 프라이버시 정보 노출을 방지하기 위하여 안전한 데이터 수집 기법들이 연구되어 왔다. 하지만,대부분의 기법들은 기밀성만 제공할 뿐,부인방지 및 익명성은 제공하지 않는다. 그리고 더 나아가 기존 기법들은 통계정보 수집과 개별적인 정보 수집을 동시에 제공하지 않는 다. 본 논문은 개별정보수집 및 통계정보 수집을 모두 지원하며 동시에,사용자에게 강화된 익명성 개념인 비연결성을 제공하는 새로운 데이터 수집 기법을 소개한다.

치과의사 맞춤형 마우스가드의 제작방법

노관태(Kwantae Noh) 대한치과의사협회 2018 대한치과의사협회지 Vol.56 No.6

The mouth guard is a device with elasticity to be installed in the oral cavity. It has a function to reduce the trauma in the oral cavity and to protect the teeth and surrounding tissues from trauma. The purpose of mouth guard is to prevent trauma and concussion. It is mandatory to wear a mouthguard in sports where there is a lot of contact and the possibility of trauma or concussion in the mouth area is high. The mouse guard is divided into a stock type, a mouth formed type, and a custom made type according to the manufacturing method. The custom made type is made on the individual dentition model and has excellent retention because of its excellent fit. Also, the effect of trauma prevention is excellent. It is possible to design and adjust by the dentist and reduce the complaint the athlete has about the mouthguard. In this article, the process of making a dentist-customized mouthguard was described.

임플란트의 위치와 방향이 좋지 않은 증례의 보철 치료

노관태(Kwantae Noh) 대한치과의사협회 2020 대한치과의사협회지 Vol.58 No.9

If the implant is planted in the wrong position or direction, it is disadvantageous for stress distribution, and it is easy to cause complications such as screw loosening, abutment fracture, and implant fracture. If the position or orientation of the implant is not good, efforts should be made to minimize the problem through proper implant prosthetic treatment. In this article, the prosthetic method for facilitating future maintenance in cases with poor implant placement or orientation will be presented