• Title/Summary/Keyword: ghost key

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A study on Detecting a Ghost-key using Additional Coating at the Membrane type Keyboard) (코팅 추가에 의한 멤브레인 키보드에서의 고스트-키 검출에 관한 연구)

  • Lee, HyunChang;Lee, MyungSeok
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.7
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    • pp.56-63
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    • 2016
  • This paper presents a novel method for detecting a ghost key at the membrane type keyboard, which has additional resistive coating to the membrane film. Also, the optimal ratio of resistances for detecting a ghost key was designed based on the characteristics of the membrane film. The optimal ratio of resistances was considered to be able to detect the worst case (i.e., difference voltage between normal key and ghost key is minimum). The ability of the proposed methods are evaluated by simulation studies in this paper. In order to verify the proposed method, the experiment was carried out with a designed circuit and A/D (analog to digital) in MCU (micro controller unit). The proposed method is implemented into the membrane type keyboard and is verified by experimental results.

A Ghost-Imaging System Based on a Microfluidic Chip

  • Wang, Kaimin;Han, Xiaoxuan;Ye, Hualong;Wang, Zhaorui;Zhang, Leihong;Hu, Jiafeng;Xu, Meiyong;Xin, Xiangjun;Zhang, Dawei
    • Current Optics and Photonics
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    • v.5 no.2
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    • pp.147-154
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    • 2021
  • Microfluidic chip technology is a research focus in biology, chemistry, and medicine, for example. However, microfluidic chips are rarely applied in imaging, especially in ghost imaging. Thus in this work we propose a ghost-imaging system, in which we deploy a novel microfluidic chip modulator (MCM) constructed of double-layer zigzag micro pipelines. While in traditional situations a spatial light modulator (SLM) and supporting computers are required, we can get rid of active modulation devices and computers with this proposed scheme. The corresponding simulation analysis verifies good feasibility of the scheme, which can ensure the quality of data transmission and achieve convenient, fast ghost imaging passively.

CKGS: A Way Of Compressed Key Guessing Space to Reduce Ghost Peaks

  • Li, Di;Li, Lang;Ou, Yu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.16 no.3
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    • pp.1047-1062
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    • 2022
  • Differential power analysis (DPA) is disturbed by ghost peaks. There is a phenomenon that the mean absolute difference (MAD) value of the wrong key is higher than the correct key. We propose a compressed key guessing space (CKGS) scheme to solve this problem and analyze the AES algorithm. The DPA based on this scheme is named CKGS-DPA. Unlike traditional DPA, the CKGS-DPA uses two power leakage points for a combined attack. The first power leakage point is used to determine the key candidate interval, and the second is used for the final attack. First, we study the law of MAD values distribution when the attack point is AddRoundKey and explain why this point is not suitable for DPA. According to this law, we modify the selection function to change the distribution of MAD values. Then a key-related value screening algorithm is proposed to obtain key information. Finally, we construct two key candidate intervals of size 16 and reduce the key guessing space of the SubBytes attack from 256 to 32. Simulation experimental results show that CKGS-DPA reduces the power traces demand by 25% compared with DPA. Experiments performed on the ASCAD dataset show that CKGS-DPA reduces the power traces demand by at least 41% compared with DPA.

Enhanced Equidistant Chosen Message Power Analysis of RSA-CRT Algorithm (RSA-CRT의 향상된 등간격 선택 평문 전력 분석)

  • Park, Jong-Yeon;Han, Dong-Guk;Yi, Ok-Yeon;Choi, Doo-Ho
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.48 no.2
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    • pp.117-126
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    • 2011
  • RSA-CRT algorithm is widely used to improve the performance of RSA algorithm. However, it is also vulnerable to side channel attacks like as general RSA. One of the power attacks on RSA-CRT, proposed by Boer et al., is a power analysis which utilizes reduction steps of RSA-CRT algorithm with equidistant chosen messages, called as ECMPA(Equidistant Chosen Messages Power Analysis) or MRED(Modular Reduction on Equidistant Data) analysis. This method is to find reduction output value r=xmodp which has the same equidistant patterns as equidistant messages. One can easily compute secret prime p from exposure of r. However, the result of analysis from a reduction step in [5] is remarkably different in our experiment from what Boer expected in [5]. Especially, we found that there are Ghost key patterns depending on the selection of attack bits and selected reduction algorithms. Thus, in this paper we propose several Ghost key patterns unknown to us until now, then we suggest enhanced and detailed analyzing methods.

Influence of Atmospheric Turbulence Channel on a Ghost-imaging Transmission System

  • Wang, Kaimin;Wang, Zhaorui;Zhang, Leihong;Kang, Yi;Ye, Hualong;Hu, Jiafeng;Xu, Jiaming
    • Current Optics and Photonics
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    • v.4 no.1
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    • pp.1-8
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    • 2020
  • We research a system of compressed-sensing computational ghost imaging (CSCGI) based on the intensity fluctuation brought by turbulence. In this system, we used the gamma-gamma intensity-fluctuation model, which is commonly used in transmission systems, to simulate the CSCGI system. By setting proper values of the parameters such as transmission distance, refractive-index structure parameter, and sampling rates, the peak signal-to-noise ratio (PSNR) performance and bit-error rate (BER) performance are obtained to evaluate the imaging quality, which provides a theoretical model to further research the ghost-imaging algorithm.

Study of the Key Technology of Ghost Imaging Based on Rosette Scanning

  • Zhang, Leihong;Kang, Yi;Pan, Zilan;Liang, Dong;Li, Bei;Zhang, Dawei;Ma, Xiuhua
    • Current Optics and Photonics
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    • v.1 no.5
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    • pp.491-499
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    • 2017
  • Ghost imaging offers great potential, with respect to standard imaging, for imaging objects in optically harsh or noisy environments. It can solve the problems that are difficult to solve by conventional imaging techniques. Recently, it has become a hot topic in quantum optics. In this paper, we propose a scheme for ghost imaging based on rosette scanning, named rosette ghost imaging. Sampling a small area sampling instead of the whole object, the instantaneous field of view of rosette scanning is used as the modulation light field in ghost imaging. This scheme reduces energy loss, the number of samples, and the sampling time, while improving the quality of the reconstructed image.

Research on Camouflaged Encryption Scheme Based on Hadamard Matrix and Ghost Imaging Algorithm

  • Leihong, Zhang;Yang, Wang;Hualong, Ye;Runchu, Xu;Dawei, Zhang
    • Current Optics and Photonics
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    • v.5 no.6
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    • pp.686-698
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    • 2021
  • A camouflaged encryption scheme based on Hadamard matrix and ghost imaging is proposed. In the process of the encryption, an orthogonal matrix is used as the projection pattern of ghost imaging to improve the definition of the reconstructed images. The ciphertext of the secret image is constrained to the camouflaged image. The key of the camouflaged image is obtained by the method of sparse decomposition by principal component orthogonal basis and the constrained ciphertext. The information of the secret image is hidden into the information of the camouflaged image which can improve the security of the system. In the decryption process, the authorized user needs to extract the key of the secret image according to the obtained random sequences. The real encrypted information can be obtained. Otherwise, the obtained image is the camouflaged image. In order to verify the feasibility, security and robustness of the encryption system, binary images and gray-scale images are selected for simulation and experiment. The results show that the proposed encryption system simplifies the calculation process, and also improves the definition of the reconstructed images and the security of the encryption system.

Research on Multiple-image Encryption Scheme Based on Fourier Transform and Ghost Imaging Algorithm

  • Zhang, Leihong;Yuan, Xiao;Zhang, Dawei;Chen, Jian
    • Current Optics and Photonics
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    • v.2 no.4
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    • pp.315-323
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    • 2018
  • A new multiple-image encryption scheme that is based on a compressive ghost imaging concept along with a Fourier transform sampling principle has been proposed. This further improves the security of the scheme. The scheme adopts a Fourier transform to sample the original multiple-image information respectively, utilizing the centrosymmetric conjugation property of the spatial spectrum of the images to obtain each Fourier coefficient in the most abundant spatial frequency band. Based on this sampling principle, the multiple images to be encrypted are grouped into a combined image, and then the compressive ghost imaging algorithm is used to improve the security, which reduces the amount of information transmission and improves the information transmission rate. Due to the presence of the compressive sensing algorithm, the scheme improves the accuracy of image reconstruction.

ODONTOGENIC GHOST CELL CARCINOMA ARISING FROM ODONTOGENIC EPITHELIAL TUMOR IN MAXILLA - A CASE REPORT (치성상피종양으로부터 상악에 발생한 치성유령세포암종의 치험례)

  • Kim, Jin-Hak;Kim, Moon-Key;Cha, In-Ho;Kim, Jin;Kim, Hyun-Sil;Choi, Hee-Soo;Kim, Hyung-Jun
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.30 no.3
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    • pp.218-222
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    • 2004
  • The neoplastic variant of calcifying odontogenic cyst has various designation, and its malignant counterpart has been reported as aggressive epithelial ghost cell tumor or odontogenic ghost cell carcinoma. Odontogenic ghost cell carcinoma(OGCC) is a rare carcinoma first documented in 1985. It is composed of varying sized islands of anucleated cells with homogenous, pale eosinophilic cytoplasm, so called ghost cells, were admixed with nucleated cells. We report a case of maxillary OGCC developed from odontogenic epithelial tumor in a 25-year-old man with literature review.

Lightweight Key Point Detection Model Based on Multi-Scale Ghost Convolution for YOLOv8 (YOLOv8 을 위한 다중 스케일 Ghost 컨볼루션 기반 경량 키포인트 검출 모델)

  • Zihao Li;Inwhee Joe
    • Proceedings of the Korea Information Processing Society Conference
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    • 2024.05a
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    • pp.604-606
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    • 2024
  • 컴퓨터 비전 응용은 우리 생활에서 중요한 역할을 한다. 현재, 대규모 모델의 등장으로 딥 러닝의 훈련 및 운행 비용이 급격히 상승하고 있다. 자원이 제한된 환경에서는 일부 AI 프로그램을 실행할 수 없게 되므로, 경량화 연구가 필요하다. YOLOv8 은 현재 주요 목표 검출 모델 중 하나이며, 본 논문은 다중 스케일 Ghost 컨볼루션 모듈을 사용하여 구축된 새로운 YOLOv8-pose-msg 키포인트 검출 모델을 제안한다. 다양한 사양에서 새 모델의 매개변수 양은 최소 34% 감소할 수 있으며, 최대 59%까지 감소할 수 있다. 종합적인 검출 성능은 비교적 대규모 데이터셋에서 원래의 수준을 유지할 수 있으며, 소규모 데이터셋에서의 키포인트 검출은 30% 이상 증가할 수 있다. 동시에 최대 25%의 훈련 및 추론 시간을 절약할 수 있다.