• Title/Summary/Keyword: A key technique

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Extraordinary State Discrimination of Grinding Wheel Surface Using Pattern Classification (패턴 분류법을 이용한 연삭 숫돌면의 이상상태 판별)

  • 유은이
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2000.04a
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    • pp.447-452
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    • 2000
  • The grinding plays a key role which decide the quality of a product finally. But the grinding process is very irregular, so it is very difficult to analyse the process accurately. Therefore it is very important in the aspect of precision and automation to reduce the idle time and to decide the proper dressing time by visualizing. In this study, we choose the direct method of observation by making use of computer vision, and apply pattern classification technique to the method of measuring the wheel surface. Pattern classification technique is proper to analyse complex surface image. We observe the change of the wheel surface by making use of the gray level run lengths which are representative prince in this technique.

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Sand Moisture Measurement with Microwave Technique in Free Space at X-Band Frequency (X-밴드 주파수의 마이크로파를 이용한 자유공간에서의 모래수분측정)

  • 남현수;성재용;박남석
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.8 no.5
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    • pp.525-533
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    • 1997
  • A nondestructive moisture measurement technique has been applied to improve the previous moisture measurement method in the building research. The experiment was done in free space using horns since it is the key element for continuous and non-destructive measurement. For this purpose a microwave bridge type analyzer at the frequency of 9.5 GHz was used to determine the moisture content of sands in the range of 1~12%. From this, the representative calibration curves were obtained. This shows that moisture measurement technique using microwave is applicabe to the measurement of moisture in non-metallic materials such as coal, pulp, foods, building materials, etc.

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Safety Techniques-Based Improvement of Task Execution Process Followed by Execution Maturity-Based Risk Management in Precedent Research Stage of Defense R&D Programs (국방 선행연구단계에서 안전분석 기법에 기반한 수행프로세스의 개선 및 수행성숙도 평가를 활용한 위험 관리)

  • Choi, Se Keun;Kim, Young-Min;Lee, Jae-Chon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.10
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    • pp.89-100
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    • 2018
  • The precedent study stage of defense programs is a project stage that is conducted to support the determination of an efficient acquisition method of the weapon system determined by the requirement. In this study, the FTA/FMEA technique was used in the safety analysis process to identify elements to be conducted in the precedent study stage and a methodology for deriving the key review elements through conceptualization and tailoring was suggested. To supplement the key elements derived from the existing research, it is necessary to analyze various events that may arise from key elements. To accomplish this, the HAZOP technique for safety analysis in other industrial fields was used to supplement the results of kdy element derivation. We analyzed and modeled the execution procedure by establishing input/output information and association with the key elements of the precedent study stage derived by linking HAZOP/FTA/FMEA techniques. In addition, performance maturity was evaluated for performance of precedent study, and a risk-based response manual was generated based on inter-working information with key elements with low maturity. Based on the results of this study, it is possible to meet the performance, cost, and schedule of the project implementation through application of the key elements and procedures and the risk management response manual in the precedent study stage of the defense program.

DNA Based Cloud Storage Security Framework Using Fuzzy Decision Making Technique

  • Majumdar, Abhishek;Biswas, Arpita;Baishnab, Krishna Lal;Sood, Sandeep K.
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.7
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    • pp.3794-3820
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    • 2019
  • In recent years, a cloud environment with the ability to detect illegal behaviours along with a secured data storage capability is much needed. This study presents a cloud storage framework, wherein a 128-bit encryption key has been generated by combining deoxyribonucleic acid (DNA) cryptography and the Hill Cipher algorithm to make the framework unbreakable and ensure a better and secured distributed cloud storage environment. Moreover, the study proposes a DNA-based encryption technique, followed by a 256-bit secure socket layer (SSL) to secure data storage. The 256-bit SSL provides secured connections during data transmission. The data herein are classified based on different qualitative security parameters obtained using a specialized fuzzy-based classification technique. The model also has an additional advantage of being able to decide on selecting suitable storage servers from an existing pool of storage servers. A fuzzy-based technique for order of preference by similarity to ideal solution (TOPSIS) multi-criteria decision-making (MCDM) model has been employed for this, which can decide on the set of suitable storage servers on which the data must be stored and results in a reduction in execution time by keeping up the level of security to an improved grade.

Methodology effects on determining the energy concentration and the apparent total tract digestibility of components in diets fed to growing pigs

  • Huang, Chengfei;Li, Ping;Ma, Xiaokang;Jaworski, Neil William;Stein, Hans-Henrik;Lai, Changhua;Zhao, Jinbiao;Zhang, Shuai
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.8
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    • pp.1315-1324
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    • 2018
  • Objective: An experiment was conducted to investigate the effects of different diet formulations: F1 (Two complicated basal diets containing different crude protein levels plus tested feedstuff) vs F2 (A simple corn soybean meal [SBM] basal diet plus tested feedstuff) combined with total collection (TC) or chromic oxide ($Cr_2O_3$) marker or acid-insoluble ash (AIA) marker method, and freeze-dry or oven-dry (OD) technique on estimation of nutrient digestibility in diets fed to growing pigs. Methods: In F1, twelve barrows were allocated to two $6{\times}4$ Youden Squares. The treatment diets included a high protein basal (HPB) diet, a low protein basal (LPB) diet, a corn diet and a wheat bran (WB) diet formulated based on the HPB diet, and a SBM diet and a rapeseed meal (RSM) diet formulated based on the LPB diet. In F2, eight barrows were allocated to two $4{\times}4$ Latin Squares. The treatment diets included a corn basal diet, a SBM basal diet formulated based on the corn diet, and a WB diet and a RSM diet formulated based on the SBM diet. Results: Concentration of digestible (DE) and metabolizable energy (ME), and the apparent total tract digestibility of gross energy, ash, neutral detergent fibre, and acid detergent fibre determined by $Cr_2O_3$ marker method were greater than those determined by TC and AIA marker methods in HPB, LPB, and RSM diets formulated by F1 and in corn diet formulated by F2 (p<0.05). The DE values in WB and both DE and ME values in SBM and RSM estimated using F1 were greater than those estimated using F2 (p<0.05). Conclusion: From the accuracy aspect, the AIA marker or TC method combined with OD technique is recommended for determining the energy concentration and nutrient digestibility of components in diets fed to growing pigs.

A Study on Implementation of Authentication System for Home Networking Service (홈 네트워크 서비스를 위한 인증시스템 구현에 관한 연구)

  • Lee, Ki-Young
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.6
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    • pp.1091-1098
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    • 2009
  • In this paper, we designed the authentication system for home network service and applied it to actual sensor nodes. The pair-wise pre-distribution key skim is applied for prevention of authentication key from sniffing on the wireless sensor networks. The authentication key and data are encrypted by using the CBC mode RC5 algorithm based on the SPINS. The experimental environment consists of a base station (BS)and sensor nodes and each sensor node sends both sensing data and the encrypted authentication key to the BS. For simulations we set up some what-if scenarios of security menaces in home network service.Slightly modified the TOS_Msg data arrays of TinyOS is suggested to store 8-byte authentication key which can enable data encryption and authentication at the each sensor node. As a result, malfunction caused by communication between BS and nodes of other groups of added nodes having malicious purpose can be protected. Also, we confirmed that a critical data of home networking service like vital signal can be transmitted securely through this system by encryption technique.

A New NTFS Anti-Forensic Technique for NTFS Index Entry (새로운 NTFS 디렉토리 인덱스 안티포렌식 기법)

  • Cho, Gyu-Sang
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.8 no.4
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    • pp.327-337
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    • 2015
  • This work provides new forensic techinque to a hide message on a directory index in Windows NTFS file system. Behavior characteristics of B-tree, which is apoted to manage an index entry, is utilized for hiding message in slack space of an index record. For hidden message not to be exposured, we use a disguised file in order not to be left in a file name attribute of a MFT entry. To understand of key idea of the proposed technique, we describe B-tree indexing method and the proposed of this work. We show the proposed technique is practical for anti-forensic usage with a real message hiding case using a developed software tool.

Optical Encryption of Binary Information using 2-step Phase-shifting Digital Holography (2-단계 위상 천이 디지털 홀로그래피를 이용한 이진 정보 광 암호화 기법)

  • Byun, Hyun-Joong;Gil, Sang-Keun
    • Korean Journal of Optics and Photonics
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    • v.17 no.5
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    • pp.401-411
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    • 2006
  • We propose an optical encryption/decryption technique for a security system based on 2-step phase-shifting digital holography. Phase-shilling digital holography is used for recording phase and amplitude information on a CCD device. 2-step phase-shifting is implemented by moving the PZT mirror with phase step of 0 or ${\pi}/2$. The binary data and the key are expressed with random code and random phase patterns. The digital hologram is a Fourier transform hologram and is recorded on CCD with 256 gray level quantization. We remove the DC term of the digital hologram fur data reconstruction, which is essential to reconstruct the original binary input data/image. The error evaluation fer the decrypted binary data is analyzed. One of errors is a quantization error in detecting the hologram intensity on CCD, and the other is generated from decrypting the data with the incorrect key. The technique using 2-step phase-shifting holography is more efficient than a 4-step method because 2-step phase-shifting holography system uses less data than the 4-step method for data storage or transmission. The simulation shows that the proposed technique gives good results fur the optical encryption of binary information.

Implementation of High-definition Digital Signage Reality Image Using Chroma Key Technique (크로마키 기법을 이용한 고해상도 디지털 사이니지 실감 영상 구현)

  • Moon, Dae-Hyuk
    • Journal of Industrial Convergence
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    • v.19 no.6
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    • pp.49-57
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    • 2021
  • Digital Signage and multi-view image system are used as the 4th media to deliver stories and information due to their strong immersion. A content image displayed on large Digital Signage is produced with the use of computer graphics, rather than reality image. That is because the images shot for content making have an extremely limited range of production and their limitation to high resolution, and thereby have difficulty being displayed in a large and wide Digital Signage screen. In case of Screen X and Escape that employ the left and right walls of in the center a movie theater as a screen, images are shot with three cameras for Digital Cinema, and are screened in a cinema with multi-view image system after stitching work is applied. Such realistic images help viewers experience real-life content. This research will be able to display high-resolution images on Digital Signage without quality degradation by using the multi-view image making technique of Screen X and Chroma key technique are showed the high-resolution Digital Signage content making method.

Semantic Occlusion Augmentation for Effective Human Pose Estimation (가려진 사람의 자세추정을 위한 의미론적 폐색현상 증강기법)

  • Hyun-Jae, Bae;Jin-Pyung, Kim;Jee-Hyong, Lee
    • KIPS Transactions on Software and Data Engineering
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    • v.11 no.12
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    • pp.517-524
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    • 2022
  • Human pose estimation is a method of estimating a posture by extracting a human joint key point. When occlusion occurs, the joint key point extraction performance is lowered because the human joint is covered. The occlusion phenomenon is largely divided into three types of actions: self-contained, covered by other objects, and covered by background. In this paper, we propose an effective posture estimation method using a masking phenomenon enhancement technique. Although the posture estimation method has been continuously studied, research on the occlusion phenomenon of the posture estimation method is relatively insufficient. To solve this problem, the author proposes a data augmentation technique that intentionally masks human joints. The experimental results in this paper show that the intentional use of the blocking phenomenon enhancement technique is strong against the blocking phenomenon and the performance is increased.