• Title/Summary/Keyword: 박스 크기

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An Efficient BC Approach to Compute Fractal Dimension of Coastlines (개선된 BC법과 해안선의 프랙탈 차원 계산)

  • So, Hye-Rim;So, Gun-Baek;Jin, Gang-Gyoo
    • Journal of Navigation and Port Research
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    • v.40 no.4
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    • pp.207-212
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    • 2016
  • The box-counting(BC) method is one of the most commonly used methods for fractal dimension calculation of binary images in the fields of Engineering, Science, Medical Science, Geology, etc due to its simplicity and reliability. It deals with only square images with each size equal to the power of 2 to prevent it from discarding unused pixels for images of arbitrary size. In this paper, we presents a more efficient BC method based on the original one, which is applicable to images of arbitrary size. The proposed approach allows the number of the counting boxes to be real to improve the estimation accuracy. The mean absolute error performance is computed on two deterministic fractal images whose theoretical dimensions are well known to compare with those of the existing BC method and triangular BC method. The experimental results show that the proposed method can outperform the two methods and assess the complexity of coastline images of Korea and Chodo island taken from the Google map.

Lightweight AES-based Whitebox Cryptography for Secure Internet of Things (안전한 사물인터넷을 위한 AES 기반 경량 화이트박스 암호 기법)

  • Lee, Jin-Min;Kim, So-Yeon;Lee, Il-Gu
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.26 no.9
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    • pp.1382-1391
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    • 2022
  • White-box cryptography can respond to white-box attacks that can access and modify memory by safely hiding keys in the lookup table. However, because the size of lookup tables is large and the speed of encryption is slow, it is difficult to apply them to devices that require real-time while having limited resources, such as IoT(Internet of Things) devices. In this work, we propose a scheme for collecting short-length plaintexts and processing them at once, utilizing the characteristics that white-box ciphers process encryption on a lookup table size basis. As a result of comparing the proposed method, assuming that the table sizes of the Chow and XiaoLai schemes were 720KB(Kilobytes) and 18,000KB, respectively, memory usage reduced by about 29.9% and 1.24% on average in the Chow and XiaoLai schemes. The latency was decreased by about 3.36% and about 2.6% on average in the Chow and XiaoLai schemes, respectively, at a Traffic Load Rate of 15 Mbps(Mega bit per second) or higher.

Comic Image Normalization using the gradient Radon Transform based on OpenCL implementation (OpenCL 기반의 그래디언트 라돈변환을 이용한 만화영상의 정규화)

  • Kim, Dong-Keun;Jeon, Hyeok-June;Hwang, Chi-Jung
    • The KIPS Transactions:PartB
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    • v.18B no.4
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    • pp.221-230
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    • 2011
  • Digital comic images are one of popular contents on the Internet. Usually, they are scanned from comic books by digital scanners. Without post-processing, they may have different sizes, skews and margins other than contents at the boundary. To normalize the size of their contents without the skews and margins is an important step in comic image analysis and application such as content-based comic image retrieval system. In this paper, we propose a method to detect a box frame in comic images by extracting of line segments using the gradient Radon transform. The box frame in comic images is the maximum rectangle which consists of contents without margins. We use the detected box frame to normalize the size of comic images and to make them no skew. In addition, the proposed method is implemented by OpenCL to speed up the detection of the line segments. Experimental results show that our proposed method effectively detects the box frame in comic images.

An Experimental Study for Structural Safety Evaluation of PSC Box Girder Bridge with FRP Struts (FRP 스트럿을 가진 PSC 박스거더교의 구조안전성 평가를 위한 실험 연구)

  • Song, Jae-Joon;Park, Jong-Hwa;Park, Kyung-Hoon;Jo, Byung-Wan
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.12 no.6
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    • pp.205-213
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    • 2008
  • The structure of PSC box girder with FRP strut has a form of supporting the cantilever part in the widened upper slab by modifying the existing PSC box girder efficiently, and it is able to build an economical and aesthetically pleasing bridge as it reduces the size of the lower structure by reducing the self-weight of the upper structure. In this research, loading test of PSC Box Girder using full-scale mock-up was conducted and FEM analysis was performed. By comparing results, structural safety of the FRP strut and the upper slab following application of the strut in the PSC Box Girder Bridge were evaluated.

A White-box ARIA Implementation (화이트박스 ARIA 구현)

  • Hong Tae Kim
    • Convergence Security Journal
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    • v.24 no.1
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    • pp.69-76
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    • 2024
  • The white-box implementation is a cryptographic technique used to protect the secret key of a cryptographic system. It is primarily employed for digital rights management for music and videos. Since 2002, numerous white-box implementations have been developed to ensure secure digital rights management. These have been applied to AES and DES. ARIA, a 128-bit block cipher with an involution substitution and permutation network (SPN), was selected as a South Korean standard in 2004. In this paper, we propose the first white-box ARIA implementation. Our implementation consists of 7,696 lookup tables, with a total size of 1,984 KB. We demonstrate that it also has considerable white-box diversity and white-box ambiguity from a security perspective.

A White Box Implementation of Lightweight Block Cipher PIPO (경량 블록 암호 PIPO의 화이트박스 구현 기법)

  • Ham, Eunji;Lee, Youngdo;Yoon, Kisoon
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.32 no.5
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    • pp.751-763
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    • 2022
  • With the recent increase in spending growth in the IoT sector worldwide, the importance of lightweight block ciphers to encrypt them is also increasing. The lightweight block cipher PIPO algorithm proposed in ICISC 2020 is an SPN-structured cipher using an unbalanced bridge structure. The white box attack model refers to a state in which an attacker may know the intermediate value of the encryption operation. As a technique to cope with this, Chow et al. proposed a white box implementation technique and applied it to DES and AES in 2002. In this paper, we propose a white box PIPO applying a white box implementation to a lightweight block cipher PIPO algorithm. In the white box PIPO, the size of the table decreased by about 5.8 times and the calculation time decreased by about 17 times compared to the white box AES proposed by Chow and others. In addition, white box PIPO was used for mobile security products, and experimental results for each test case according to the scope of application are presented.

Item Arrangement Optimization Algorithm Considering Product Characteristics (상품 특성을 고려한 상품 배치 최적화 알고리즘)

  • Cho-Won Lim;Jong-Min Lee;Tae-Yeon Kim
    • Proceedings of the Korea Information Processing Society Conference
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    • 2023.05a
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    • pp.18-19
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    • 2023
  • 최근 상품의 특성을 고려하지 않은 박스 크기 선택과 박스 공간 내 비효율적인 상품 배치로 인하여 박스의 파손 문제가 지속적으로 제기되고 있다. 이는 적재하고자 하는 상품의 특성을 고려하지 않고 상품을 대략적으로 배치하기 때문이다. 따라서 본 논문에서는 면적과 무게와 같은 상품의 특성을 고려한 상품 배치 최적화 알고리즘을 제안하여 공간 배치의 비효율성 문제를 최소화하고자 한다. 제안한 상품 배치 최적화 알고리즘은 검색 트리 (search tree)와 상품 특성 기반 평가 함수(evaluation function)로 구성되어 있다. 상품 특성 기반 평가 함수는 면적, 무게 및 바닥에 닿는 면적을 고려하여 설계되었다.

Adaptive thresholding for two-dimensional barcode images using two thresholds and the integral image (이중 문턱 값과 적분영상을 이용한 2차원 바코드 영상의 적응적 이진화)

  • Lee, Yeon-Kyung;Yoo, Hoon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.11
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    • pp.2453-2458
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    • 2012
  • In this paper, we propose an adaptive thresholding method to binarize two-dimensional barcode images. Adaptive thresholding methods that minimize light effects convert an original image into a binary image. The methods are applied to document image binarization. The methods, however, have problems of determining box size used in adaptive thresholding. thus, they inappropriate to use in recognition of two-dimensional barcode images. To overcome the problem, we analysis the problem and propose a new adaptive threshold method using the integral image. To show the effectiveness of our method, we compared our method with the well-known existing methods in terms of visual quality and processing time. The experimental result indicates that the proposed method is superior to the existing method.

Design of Real-time MR Contents using Substitute Videos of Vehicles and Background based on Black Box Video (블랙박스 영상 기반 차량 및 배경 대체 영상을 이용한 실시간 MR 콘텐츠의 설계)

  • Kim, Sung-Ho
    • Journal of Convergence for Information Technology
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    • v.11 no.6
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    • pp.213-218
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    • 2021
  • In this paper, we detect and track vehicles by type based on highway daytime driving videos taken with black boxes for vehicles. In addition, we design a real-time MR contents production method that can be newly created by placing substitute videos of each type of detected vehicles in the same location as the new background video. To detect and track vehicles by type, we use the YOLO algorithm. And we also use the mask technique based on RGB color for substitute videos of each type of vehicles detected. The size of the vehicle substitute videos to be used for MR content are substituted by the same size as the area size of the detected vehicles. In this paper, we confirm that real-time MR contents design is possible as a result of experiments and simulations and believe that It will be usefully utilized in the field of VR contents.

Transverse Stress of Slabs due tp Longitudinal Prestressing in Prestressed Concrete Box Girders (프리스트레스트 콘크리트 박스 거더의 종방향 프리스트레싱에 의한 슬래브의 횡방향 응력)

  • Yang, In-Hwan
    • Journal of the Korea Concrete Institute
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    • v.15 no.5
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    • pp.679-688
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    • 2003
  • For box girders in which the longitudinal tendon is profiled in the inclined webs, longitudinal prestressing force will induce transverse effects as well as longitudinal ones. In this paper, the method to estimate transverse effects induced by longitudinal prestressing is proposed. The concept of transverse equivalent loading which is calculated through longitudinal prestressing analysis is developed. The transverse stress in slabs of box girders due to longitudinal prestressing are investigated. The comparison of numerical results of the proposed method and those of folded plate method represents that the method is reasonable. Numerical analyses are carried out depending on the parameters such as web inclination and ratio of girder length to tendon eccentricity. Analysis results show that when only prestressing are considered the magnitude of transverse stress in slabs of box girder is not so large. However, if the other stresses due to dead and live load et al. are superposed on these stresses, it may be that the longitudinal prestressing effects are significant.