• Title/Summary/Keyword: Visual block

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Proposal of Kiosk Payment Security System using Public Blockchain (솔라나 블록체인을 이용한 키오스크 결제 데이터 보안 시스템 제안)

  • Kim, Seong-Heon;Kang, hyeok;Lee, Keun-ho
    • Journal of Internet of Things and Convergence
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    • v.8 no.5
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    • pp.55-61
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    • 2022
  • Today's payment systems are becoming unmanned and changing to a way of paying with kiosks. This has the advantage of convenient payment because consumers can select a menu and specify the number of products to be purchased with just a touch of the screen. However, from the point of view of system security, the actual kiosk system has various vulnerabilities. This can hijack the administrator account, gain system privileges, and perform malicious actions. In addition, it is exposed to a number of security threats, such as the possibility of wasting unnecessary resources by abnormally increasing the number of payments, and causing the device to fail to operate normally. Therefore, in this paper, if any node of a participant in the solana blockchain approves an incorrect fork, the stake of the voting nodes is deleted. Also, since all participants can see the transaction history due to the nature of the block chain, I intend to write a thesis on a system that improves the vulnerability of kiosk payments by separating the access rights through the private blockchain.

Assembly Performance Evaluation for Prefabricated Steel Structures Using k-nearest Neighbor and Vision Sensor (k-근접 이웃 및 비전센서를 활용한 프리팹 강구조물 조립 성능 평가 기술)

  • Bang, Hyuntae;Yu, Byeongjun;Jeon, Haemin
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.35 no.5
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    • pp.259-266
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    • 2022
  • In this study, we developed a deep learning and vision sensor-based assembly performance evaluation method isfor prefabricated steel structures. The assembly parts were segmented using a modified version of the receptive field block convolution module inspired by the eccentric function of the human visual system. The quality of the assembly was evaluated by detecting the bolt holes in the segmented assembly part and calculating the bolt hole positions. To validate the performance of the evaluation, models of standard and defective assembly parts were produced using a 3D printer. The assembly part segmentation network was trained based on the 3D model images captured from a vision sensor. The sbolt hole positions in the segmented assembly image were calculated using image processing techniques, and the assembly performance evaluation using the k-nearest neighbor algorithm was verified. The experimental results show that the assembly parts were segmented with high precision, and the assembly performance based on the positions of the bolt holes in the detected assembly part was evaluated with a classification error of less than 5%.

Comparison of clinical efficacy of ropivacaine and lignocaine with adrenaline for implant surgery anesthesia: a split-mouth randomized controlled clinical trial

  • Kalath, Remya Nath;Kulal, Rithesh;Gopinath, Sharika
    • Journal of Dental Anesthesia and Pain Medicine
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    • v.21 no.4
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    • pp.337-344
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    • 2021
  • Background: The primary indication for using long-acting anesthetics in dentistry is extensive dental procedures that require pulpal anesthesia beyond 90 min and management of postoperative pain. Ropivacaine is an amide local anesthetic that is available at various concentrations with inherent vasoconstrictive properties at low concentrations. Ropivacaine has a 75% greater margin of safety than bupivacaine. Ropivacaine can be a good alternative to bupivacaine as a local anesthetic in dental implant surgery as it provides a longer duration of both pulpal and soft tissue anesthesia after mandibular nerve block and lowers CNS and cardiovascular toxicity. This study aimed to evaluate and compare the clinical efficacy of ropivacaine and lignocaine for implant surgery anesthesia. Methods: Fifteen patients with bilateral edentulous sites indicated for implant placement were recruited for this study. Patients aged 20-60 years of both sexes were randomly recruited. Thirty implant placements were performed in the test and control groups using ropivacaine and lignocaine with adrenaline as local anesthetics, respectively. Results: The results were analyzed statistically. The duration of anesthesia was significantly higher in the test group than in the control group. Ropivacaine was found to be superior to lignocaine in terms of the quality of anesthesia. The comparison of mean visual analog scale scores showed ropivacaine to have better anesthetic and analgesic effects than the control group. Conclusion: Ropivacaine 0.75% provides a significantly longer duration of anesthesia than lignocaine 2% with adrenaline. Ropivacaine 0.75% decreased intraoperative and postoperative analgesia compared to lignocaine 2% with adrenaline. Hence, ropivacaine 0.75% can be used as an alternative to lignocaine in implant surgeries and other intraoral surgical procedures that require a longer duration of anesthesia and analgesia.

Analysis of the Current Status of NFT Art and Methodology on Utilizing Domestic Artworks (NFT예술 현황 분석과 국내 미술작품 활용방안 연구)

  • Lee, Ahn
    • The Journal of the Convergence on Culture Technology
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    • v.8 no.6
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    • pp.215-222
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    • 2022
  • This study summarizes the basic concepts of NFT art and analyzes trends in the domestic and international NFT market to provide a better understanding of the art form to suggest various ways to utilize the art in near future when social interests in technologies such as metaverse, block chain, and NFTs are continuously increasing. In addition, by examining the rapid development and process of blockchain technology in overseas markets, and confirming cases of information transfer to various metaverses such as cryptocurrency and NFT technology, the aim is to present a foothold for the future direction of national arts in general. To this end, in order to analyze consumers' perceptions and preferences, and to draw conclusions about current NFT arts at home and abroad, a survey was conducted on NFT awareness among participants of an art fair in Gwangjin-gu, Seoul. It is hoped that this study will become a cornerstone of research on NFT works and NFT art industry, which is becoming a global issue.

Stain Fungi and Discoloration Control on Rubberwood (Hevea brasiliensis Muell. Arg.) by Vacuum-Pressure Treatment with Catechin from Gambir (Uncaria gambir Roxb.)

  • Dodi NANDIKA;Elis Nina HERLIYANA;Arinana ARINANA;Yusuf Sudo HADI;Mohamad Miftah RAHMAN
    • Journal of the Korean Wood Science and Technology
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    • v.51 no.3
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    • pp.183-196
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    • 2023
  • Recently, the morphological and molecular features of five stain fungi infecting rubberwood (Hevea brasiliensis), namely Paecilomyces maximus, Paecilomyces formosus, Penicillium crustosum, Paecilomyces lecythidis and Aspergillus chevalieri, have been studied. Prior to this study, the authors revealed that catechin from gambir (Uncaria gambir) could inhibit the growth of the white-rot fungus Schizophyllum commune, and it was important to determine the bioactivity of the aforementioned agent against A. chevalieri. The efficacy of the biocidal agent was examined using a laboratory wooden block test. Rubberwood blocks, 8 mm in thickness, 20 mm in width, and 30 mm in length, were impregnated with catechin solution at concentrations of 6%, 9%, 12%, and 15% (w/v) using the vacuum-pressure method, and their bioactivity was monitored over three weeks through visual and scanning electron microscope assessment of fungal growth as well as the discoloration intensity of the wood samples. The results showed that catechin treatment increased the resistance of wood samples to A. chevalieri. Overall, the higher the catechin concentration, the lower the fungal growth. The lowest fungal growth was observed in the wood samples treated with 12% and 15% catechin (score of 0), demonstrating no discoloration. In contrast, the fungal growth score of the untreated wood samples reached 4, indicating severe discoloration. Catechins appear to be adequate biofungicides against stain fungi in rubberwood.

Effectiveness of pre-injection use of cryoanesthesia as compared to topical anesthetic gel in reducing pain perception during palatal injections: a randomized controlled trial

  • Siddhartha Rai;Mehul Rajesh Jaisani;Ashok Dongol;Pradeep Acharya;Anjani Kumar Yadav
    • Journal of Dental Anesthesia and Pain Medicine
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    • v.24 no.2
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    • pp.91-99
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    • 2024
  • Background: Palatal injections are often painful. We aimed to compare topical ice and 20% benzocaine gel for pre-injection anesthesia before greater palatine nerve block (GPNB) injections. Methods: A randomized split-mouth clinical trial was conducted among patients aged 15-60-years needing bilateral GPNB injections. A total of 120 palatal sites from 60 patients were randomly allocated to Group A (topical ice) or Group B (20% benzocaine gel). Pain was evaluated using sound, eye, motor (SEM), and the visual analog scale (VAS) in both groups. Inferential analysis was performed using the Mann-Whitney U test. Results: The mean age of the participants was 20.5 ± 3.9 years. The median VAS score for group A was 11 (Q1 - Q3: 5.25 - 21.75), which was slightly higher than the 10 (Q1 - Q3: 4.0 - 26.75) reported in group B. However, the difference was not statistically significant (P = 0.955). The median SEM score for group A and group B was 3.5 (Q1 - Q3: 3.0 - 4.0) and 4.0 (Q1 - Q3: 3.0 - 4.0), respectively, which was statistically insignificant (P = 0.869). Conclusion: Using ice as a form of topical anesthetic for achieving pre-injection anesthesia before GPNB was as effective as 20% benzocaine gel.

Image Watermarking for Copyright Protection of Images on Shopping Mall (쇼핑몰 이미지 저작권보호를 위한 영상 워터마킹)

  • Bae, Kyoung-Yul
    • Journal of Intelligence and Information Systems
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    • v.19 no.4
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    • pp.147-157
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    • 2013
  • With the advent of the digital environment that can be accessed anytime, anywhere with the introduction of high-speed network, the free distribution and use of digital content were made possible. Ironically this environment is raising a variety of copyright infringement, and product images used in the online shopping mall are pirated frequently. There are many controversial issues whether shopping mall images are creative works or not. According to Supreme Court's decision in 2001, to ad pictures taken with ham products is simply a clone of the appearance of objects to deliver nothing but the decision was not only creative expression. But for the photographer's losses recognized in the advertising photo shoot takes the typical cost was estimated damages. According to Seoul District Court precedents in 2003, if there are the photographer's personality and creativity in the selection of the subject, the composition of the set, the direction and amount of light control, set the angle of the camera, shutter speed, shutter chance, other shooting methods for capturing, developing and printing process, the works should be protected by copyright law by the Court's sentence. In order to receive copyright protection of the shopping mall images by the law, it is simply not to convey the status of the product, the photographer's personality and creativity can be recognized that it requires effort. Accordingly, the cost of making the mall image increases, and the necessity for copyright protection becomes higher. The product images of the online shopping mall have a very unique configuration unlike the general pictures such as portraits and landscape photos and, therefore, the general image watermarking technique can not satisfy the requirements of the image watermarking. Because background of product images commonly used in shopping malls is white or black, or gray scale (gradient) color, it is difficult to utilize the space to embed a watermark and the area is very sensitive even a slight change. In this paper, the characteristics of images used in shopping malls are analyzed and a watermarking technology which is suitable to the shopping mall images is proposed. The proposed image watermarking technology divide a product image into smaller blocks, and the corresponding blocks are transformed by DCT (Discrete Cosine Transform), and then the watermark information was inserted into images using quantization of DCT coefficients. Because uniform treatment of the DCT coefficients for quantization cause visual blocking artifacts, the proposed algorithm used weighted mask which quantizes finely the coefficients located block boundaries and coarsely the coefficients located center area of the block. This mask improves subjective visual quality as well as the objective quality of the images. In addition, in order to improve the safety of the algorithm, the blocks which is embedded the watermark are randomly selected and the turbo code is used to reduce the BER when extracting the watermark. The PSNR(Peak Signal to Noise Ratio) of the shopping mall image watermarked by the proposed algorithm is 40.7~48.5[dB] and BER(Bit Error Rate) after JPEG with QF = 70 is 0. This means the watermarked image is high quality and the algorithm is robust to JPEG compression that is used generally at the online shopping malls. Also, for 40% change in size and 40 degrees of rotation, the BER is 0. In general, the shopping malls are used compressed images with QF which is higher than 90. Because the pirated image is used to replicate from original image, the proposed algorithm can identify the copyright infringement in the most cases. As shown the experimental results, the proposed algorithm is suitable to the shopping mall images with simple background. However, the future study should be carried out to enhance the robustness of the proposed algorithm because the robustness loss is occurred after mask process.

Real-Time Video Quality Assessment of Video Communication Systems (비디오 통신 시스템의 실시간 비디오 품질 측정 방법)

  • Kim, Byoung-Yong;Lee, Seon-Oh;Jung, Kwang-Su;Sim, Dong-Gyu;Lee, Soo-Youn
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.46 no.3
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    • pp.75-88
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    • 2009
  • This paper presents a video quality assessment method based on quality degradation factors of real-time multimedia streaming services. The video quality degradation is caused by video source compression and network states. In this paper, we propose a blocky metric on an image domain to measure quality degradation by video compression. In this paper, the proposed boundary strength index for the blocky metric is defined by ratio of the variation of two pixel values adjacent to $8{\times}8$ block boundary and the average variation at several pixels adjacent to the two boundary pixels. On the other hand, unnatural image movement caused by network performance deterioration such as jitter and delay factors can be observed. In this paper, a temporal-Jerkiness measurement method is proposed by computing statistics of luminance differences between consecutive frames and play-time intervals between frames. The proposed final Perceptual Video Quality Metric (PVQM) is proposed by consolidating both blocking strength and temporal-jerkiness. To evaluate performance of the proposed algorithm, the accuracy of the proposed algorithm is compared with Difference of Mean Opinion Score (DMOS) based on human visual system.

Performance Analysis of Implementation on Image Processing Algorithm for Multi-Access Memory System Including 16 Processing Elements (16개의 처리기를 가진 다중접근기억장치를 위한 영상처리 알고리즘의 구현에 대한 성능평가)

  • Lee, You-Jin;Kim, Jea-Hee;Park, Jong-Won
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.49 no.3
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    • pp.8-14
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    • 2012
  • Improving the speed of image processing is in great demand according to spread of high quality visual media or massive image applications such as 3D TV or movies, AR(Augmented reality). SIMD computer attached to a host computer can accelerate various image processing and massive data operations. MAMS is a multi-access memory system which is, along with multiple processing elements(PEs), adequate for establishing a high performance pipelined SIMD machine. MAMS supports simultaneous access to pq data elements within a horizontal, a vertical, or a block subarray with a constant interval in an arbitrary position in an $M{\times}N$ array of data elements, where the number of memory modules(MMs), m, is a prime number greater than pq. MAMS-PP4 is the first realization of the MAMS architecture, which consists of four PEs in a single chip and five MMs. This paper presents implementation of image processing algorithms and performance analysis for MAMS-PP16 which consists of 16 PEs with 17 MMs in an extension or the prior work, MAMS-PP4. The newly designed MAMS-PP16 has a 64 bit instruction format and application specific instruction set. The author develops a simulator of the MAMS-PP16 system, which implemented algorithms can be executed on. Performance analysis has done with this simulator executing implemented algorithms of processing images. The result of performance analysis verifies consistent response of MAMS-PP16 through the pyramid operation in image processing algorithms comparing with a Pentium-based serial processor. Executing the pyramid operation in MAMS-PP16 results in consistent response of processing time while randomly response time in a serial processor.

Research on Geometric Shape in the 20th Century Design Education - Focused on the relation of $Fr{\ddot{o}}bel$ Kindergarten Education - (20세기 디자인교육의 기하학적인 형태에 대한 탐구 - 프뢰벨 유치원 교육과의 연관성을 중심으로 -)

  • Bang, Kyung-Rhan
    • Archives of design research
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    • v.18 no.2 s.60
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    • pp.325-334
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    • 2005
  • The purpose of this thesis is to explore the fundamental reasons and general circumstances of the introduction of geometric shape to the 20th century's design education. The modern design education was directly influenced by the German Kindergarten Movement and its educational ideal, so they began to employ geometric shapes in visual education. When Friedrich Frobel, a professional German child educator of the 19th century, invented the 'Spielgaben,' it soon became a popular educational tool. It was a turning point in the child educational system, from then they began to actively employ 'tools' in art education. The Spielgaben was created based on the geometric principle of a popular block game of the 19th century. On the other hand, a game program called 'Bechaftigungsmaterial' led early Modernists to adopt geometric shape in their works. Then, geometric shape were applied to a primary educational program designed by the Bauhaus that gave birth to the Modern design education in the 20th century. likewise, the substantial reasons why the principles of point/line/plain and geometric shapes had been taken in the 20th century design education can be explained through this historical background. This research is to investigate how Kindergarten Movement and Modern design education can be associated with each other, particularly in the light of geometric elements. Therefore, I first referred to the historic records in order to reveal their relation, and then analyzed the similarities and differences between the two activities. In result, I could explore the relationship between child educational tools and the 20th century's design education.

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