• Title/Summary/Keyword: 강인화

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Real-time Watermarking Algorithm using Multiresolution Statistics for DWT Image Compressor (DWT기반 영상 압축기의 다해상도의 통계적 특성을 이용한 실시간 워터마킹 알고리즘)

  • 최순영;서영호;유지상;김대경;김동욱
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.13 no.6
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    • pp.33-43
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    • 2003
  • In this paper, we proposed a real-time watermarking algorithm to be combined and to work with a DWT(Discrete Wavelet Transform)-based image compressor. To reduce the amount of computation in selecting the watermarking positions, the proposed algorithm uses a pre-established look-up table for critical values, which was established statistically by computing the correlation according to the energy values of the corresponding wavelet coefficients. That is, watermark is embedded into the coefficients whose values are greater than the critical value in the look-up table which is searched on the basis of the energy values of the corresponding level-1 subband coefficients. Therefore, the proposed algorithm can operate in a real-time because the watermarking process operates in parallel with the compression procession without affecting the operation of the image compression. Also it improved the property of losing the watermark and the efficiency of image compression by watermark inserting, which results from the quantization and Huffman-Coding during the image compression. Visual recognizable patterns such as binary image were used as a watermark The experimental results showed that the proposed algorithm satisfied the properties of robustness and imperceptibility that are the major conditions of watermarking.

[Retracted] Inhibitory activity against biological enzyme and anti-microbial activity of phenolics from Sambucus sieboldiana var. pendula Leaves ([논문 철회] 말오줌나무(Sambucus sieboldiana var. pendula) 잎 유래 phenol성 물질의 생리활성 효소 저해 및 항균효과)

  • Lee, Eun-Ho;Hong, Shin Hyub;Park, Hye-Jin;Kim, Byung-Oh;Jung, Hee-Young;Kang, In-Kyu;Cho, Young-Je
    • Journal of Applied Biological Chemistry
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    • v.64 no.1
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    • pp.5-11
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    • 2021
  • The phenolics of Sambucus sieboldiana var. pendula leaves for functional resources were examined on inhibitory activity against biological enzyme and anti-microbial activity. The amount of phenolic compounds were 11.60±0.18 and 12.43±0.07 mg/g by water and 50% ethanol extraction, respectively. The antioxidative activity of phenolic in extracts was higher than solids. The inhibition activities on angiotensin converting enzyme were 92.08 and 78.33% at 200 ㎍/mL phenolic concentration in water and ethanol extracts, respectively. The xanthine oxidase inhibitory activity were 100% at 200 ㎍/mL phenolic in water and ethanol extracts, respectively. These result was higher than 70.37% of allopurinol as positive control at 200 ㎍/mL. The inhibitory activity against hyaluronidase were each 25.35 and 43.38% in water and ethanol extracts. The water extract from S. sieboldiana var. pendula leaves showed antibacterial activity on the Propionebacterium acnes, Staphylococcus aureus and Streptococcus mutans in water extract and S. mutans in ethanol extract. This result suggests that phenolic from S. sieboldiana var. pendula leaves are suitable as functional foods with anti-hypertension, anti-gout, anti-inflammation and anti-microorganism activities.

Method of Deriving Activity Relationship and Location Information from BIM Model for Construction Schedule Management (공정관리 활용을 위한 BIM모델의 공정별 수순 및 위치정보 추출방안)

  • Yoon, Hyeongseok;Lee, Jaehee;Hwang, Jaeyeong;Kang, Hyojeong;Park, sangmi;Kang, Leenseok
    • Korean Journal of Construction Engineering and Management
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    • v.23 no.2
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    • pp.33-44
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    • 2022
  • The simulation function by the 4D system is a representative BIM function in the construction stage. For the 4D simulation, schedule information for each activity must be created and then linked with the 3D model. Since the 3D model created in the design stage does not consider schedule information, there are practical difficulties in the process of creating schedule information for application to the construction stage and linking the 3D model. In this study, after extracting the schedule information of the construction stage using the HDBSCAN algorithm from the 3D model in the design stage, authors propose a methodology for automatically generating schedule information by identifying precedence and sequencing relationships by applying the topological alignment algorithm. Since the generated schedule information is created based on the 3D model, it can be used as information that is automatically linked by the common parameters between the schedule and the 3D model in the 4D system, and the practical utility of the 4D system can be increased. The proposed methodology was applied to the four bridge projects to confirm the schedule information generation, and applied to the 4D system to confirm the simplification of the link process between schedule and 3D model.

Application Method of Phase Division of Fast Track for Construction Project with Complex Structures (복합공종으로 구성된 건설공사의 패스트트랙 단계구분 적용 방식 분석)

  • Kim, Hyun Soo;Hwang, Jae Yoeng;Kang, Hyo Jeong;Park, Sang Mi;Lee, Jae Hee;Kang, Leen Seok
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.42 no.1
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    • pp.95-105
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    • 2022
  • Recently, as the scale of a construction project has become larger and more complicated, there are many cases where construction projects with complex structures are carried out in a fast track method to save construction duration. In the fast track method, the proper division of construction phases is an important issue in determining the overall project period. This study presents a rational phase division method that can be applied when a construction project with complex structures is carried out as a fast track. For this study, a subdivided work breakdown structure (WBS) is developed using the construction of 4 soccer stadiums as application examples, and the schedule is analyzed by dividing the construction process of major phases. To this end, five proposals are applied to analyze the adequacy of the fast track phase division. For the draft with the minimum construction period, the fast track phase division and the schedule model of by each phase were presented. This methodology can have an application in the appropriate phase division and schedule model by construction phase when fast track is applied in large construction project of a similar size.

A Study on the Accuracy Comparison of Object Detection Algorithms for 360° Camera Images for BIM Model Utilization (BIM 모델 활용을 위한 360° 카메라 이미지의 객체 탐지 알고리즘 정확성 비교 연구)

  • Hyun-Chul Joo;Ju-Hyeong Lee;Jong-Won Lim;Jae-Hee Lee;Leen-Seok Kang
    • Land and Housing Review
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    • v.14 no.3
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    • pp.145-155
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    • 2023
  • Recently, with the widespread adoption of Building Information Modeling (BIM) technology in the construction industry, various object detection algorithms have been used to verify errors between 3D models and actual construction elements. Since the characteristics of objects vary depending on the type of construction facility, such as buildings, bridges, and tunnels, appropriate methods for object detection technology need to be employed. Additionally, for object detection, initial object images are required, and to obtain these, various methods, such as drones and smartphones, can be used for image acquisition. The study uses a 360° camera optimized for internal tunnel imaging to capture initial images of the tunnel structures of railway and road facilities. Various object detection methodologies including the YOLO, SSD, and R-CNN algorithms are applied to detect actual objects from the captured images. And the Faster R-CNN algorithm had a higher recognition rate and mAP value than the SSD and YOLO v5 algorithms, and the difference between the minimum and maximum values of the recognition rates was small, showing equal detection ability. Considering the increasing adoption of BIM in current railway and road construction projects, this research highlights the potential utilization of 360° cameras and object detection methodologies for tunnel facility sections, aiming to expand their application in maintenance.

A New Access Certification System with Temporal Key Stroke Information (키 입력 시간차이를 이용한 새로운 접속인증 시스템 소개)

  • Choi, Wonyong;Kim, Sungjin;Heo, Kangin;Moon, Gyu
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.5 no.4
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    • pp.45-53
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    • 2015
  • In this paper, an approach of temporal certification system that can be easily added on current character-based certification system is newly introduced. This technique enhances the security of the password certification process by exploiting temporal information for each character's stroke timing, and using them as another feature of certification information, on top of character comparison process. There are three different temporal conditions: maximum, minimum and no-option. The maximum condition along with a time number (usually 0.2 second or less) means that the next key input should be punched within the time limit, while the minimum condition means the next key stroke should be typed after the time lapse specified. With no-option condition chosen, user can punch the password without any timing constraints. Prototype was developed and tested with four number password case. In comparison with 104 cases, this new approach increases the cases more than 10 digits, enhancing the security of the certification process. One big advantage of this new approach is that user can update his/her password only with different timing constraints, still keeping the same characters, that will enhance the security system management efficiency in a very simple way. Figures and pictures along with process flow are included for the validity of the idea.

Development of 4D System based on New Methodology for Visualizing Construction Schedule Data for Civil Engineering Projects (토목시설물 공사관리 시각화를 취한 4D시스템 적용방안)

  • Kang, Leen Seok;Jee, Sang Bok
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.1D
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    • pp.95-103
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    • 2006
  • One of the main functions of the 4D system includes visualizing numerical schedule data in construction. The existing 4D tools have an excellent function for simulating building projects that all activities are progressed according to vertical work zone. However, it is not easy to implement all of it in the civil engineering project because the construction activities of highway and railway projects are progressed on the horizontal work zone and the 4D simulation for those projects should include earthwork objects that depend on the natural ground condition. This study suggests a new methodology for improving those limitations of 4D system for the civil engineering project and develops a new system by the suggested methodology. To verify the developed system, this study attempts to simulate 4D object for horizontal elements such as earthwork, paving work and tunneling work. The morphing and multi-texturing techniques developed in the study can be new approaches to simulate 4D object for the earthwork such as cutting and banking whose activities are progressed on the natural ground condition. The research results can be expected as a draft function for improving the application of 4D system in civil engineering projects.

Development of Greenhouse Environment Monitoring & Control System Based on Web and Smart Phone (웹과 스마트폰 기반의 온실 환경 제어 시스템 개발)

  • Kim, D.E.;Lee, W.Y.;Kang, D.H.;Kang, I.C.;Hong, S.J.;Woo, Y.H.
    • Journal of Practical Agriculture & Fisheries Research
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    • v.18 no.1
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    • pp.101-112
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    • 2016
  • Monitoring and control of the greenhouse environment play a decisive role in greenhouse crop production processes. The network system for greenhouse control was developed by using recent technologies of networking and wireless communications. In this paper, a remote monitoring and control system for greenhouse using a smartphone and a computer with internet has been developed. The system provides real-time remote greenhouse integrated management service which collects greenhouse environment information and controls greenhouse facilities based on sensors and equipments network. Graphical user interface for an integrated management system was designed with bases on the HMI and the experimental results showed that a sensor data and device status were collected by integrated management in real-time. Because the sensor data and device status can be displayed on a web page, transmitted using the server program to remote computer and mobile smartphone at the same time. The monitored-data can be downloaded, analyzed and saved from server program in real-time via mobile phone or internet at a remote place. Performance test results of the greenhouse control system has confirmed that all work successfully in accordance with the operating conditions. And data collections and display conditions, event actions, crops and equipments monitoring showed reliable results.

A Polarization-based Frequency Scanning Interferometer and the Measurement Processing Acceleration based on Parallel Programing (편광 기반 주파수 스캐닝 간섭 시스템 및 병렬 프로그래밍 기반 측정 고속화)

  • Lee, Seung Hyun;Kim, Min Young
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.8
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    • pp.253-263
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    • 2013
  • Frequency Scanning Interferometry(FSI) system, one of the most promising optical surface measurement techniques, generally results in superior optical performance comparing with other 3-dimensional measuring methods as its hardware structure is fixed in operation and only the light frequency is scanned in a specific spectral band without vertical scanning of the target surface or the objective lens. FSI system collects a set of images of interference fringe by changing the frequency of light source. After that, it transforms intensity data of acquired image into frequency information, and calculates the height profile of target objects with the help of frequency analysis based on Fast Fourier Transform(FFT). However, it still suffers from optical noise on target surfaces and relatively long processing time due to the number of images acquired in frequency scanning phase. 1) a Polarization-based Frequency Scanning Interferometry(PFSI) is proposed for optical noise robustness. It consists of tunable laser for light source, ${\lambda}/4$ plate in front of reference mirror, ${\lambda}/4$ plate in front of target object, polarizing beam splitter, polarizer in front of image sensor, polarizer in front of the fiber coupled light source, ${\lambda}/2$ plate between PBS and polarizer of the light source. Using the proposed system, we can solve the problem of fringe image with low contrast by using polarization technique. Also, we can control light distribution of object beam and reference beam. 2) the signal processing acceleration method is proposed for PFSI, based on parallel processing architecture, which consists of parallel processing hardware and software such as Graphic Processing Unit(GPU) and Compute Unified Device Architecture(CUDA). As a result, the processing time reaches into tact time level of real-time processing. Finally, the proposed system is evaluated in terms of accuracy and processing speed through a series of experiment and the obtained results show the effectiveness of the proposed system and method.

Efficacy of ISO 9001 : 2000 Quality Management System in Human Assisted Reproductive Technology Center (보조생식술 센터에서 ISO 9001 : 2000 품질경영시스템의 도입 및 시행의 효용성)

  • Jun, Jin-Hyun;Park, Yong-Seog;Lee, Hyoung-Song;Kim, Soon-Duk;Hwang, Son-Hee;Han, Su-Kyoung;Kim, Jae-Ho;Song, In-Ok;Kang, Inn-Soo;Koong, Mi-Kyoung
    • Clinical and Experimental Reproductive Medicine
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    • v.34 no.2
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    • pp.107-115
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    • 2007
  • Objective: A quality management system of international standardization organization (ISO) 9001:2000 has been proposed to properly evaluate and improve the quality of productions and services. The purpose of this article was to describe on successful introduction and application of the ISO system to human assisted reproductive technology (ART) center. Methods: Center for reproductive medicine and infertility of Cheil General Hospital started the action for ISO 9001:2000 certification at January-2004. The ISO system of our center was monitored by measuring the customer satisfaction index and periodical internal and external audit. Reports of non-conformity described corrective and preventive actions for problems and occurrences that were not consistent with the standard process and operation of our center. Continuous management and improvement were performed on the project of customer dissatisfaction. Results: Our center has got the certification of ISO 9001:2000 for "Research and development of IVF-ET program for infertility treatment" from Korean Foundation for Quality at June-2004. The policy of ISO was "To establish the best center of reproductive medicine and infertility" and "To establish the best quality management system". We found 140 cases and 7 cases of non-conformity in internal and external audit for three years, respectively, and performed corrective action. Conclusion: Improvement of customer satisfaction, systemic documentation and transparency and efficacy of working procedure were achieved by application and operation of the ISO system to our center. This ISO system could be used as a basic institutional management system for the national guideline to the human ART center.