• Title/Summary/Keyword: 라이

Search Result 6,622, Processing Time 0.045 seconds

A Scalable Montgomery Modular Multiplier (확장 가능형 몽고메리 모듈러 곱셈기)

  • Choi, Jun-Baek;Shin, Kyung-Wook
    • Journal of IKEEE
    • /
    • v.25 no.4
    • /
    • pp.625-633
    • /
    • 2021
  • This paper describes a scalable architecture for flexible hardware implementation of Montgomery modular multiplication. Our scalable modular multiplier architecture, which is based on a one-dimensional array of processing elements (PEs), performs word parallel operation and allows us to adjust computational performance and hardware complexity depending on the number of PEs used, NPE. Based on the proposed architecture, we designed a scalable Montgomery modular multiplier (sMM) core supporting eight field sizes defined in SEC2. Synthesized with 180-nm CMOS cell library, our sMM core was implemented with 38,317 gate equivalents (GEs) and 139,390 GEs for NPE=1 and NPE=8, respectively. When operating with a 100 MHz clock, it was evaluated that 256-bit modular multiplications of 0.57 million times/sec for NPE=1 and 3.5 million times/sec for NPE=8 can be computed. Our sMM core has the advantage of enabling an optimized implementation by determining the number of PEs to be used in consideration of computational performance and hardware resources required in application fields, and it can be used as an IP (intellectual property) in scalable hardware design of elliptic curve cryptography (ECC).

Analysis and Implications of Private-led Library Services for the Disabled in Major Advanced Countries (주요 선진국 민간주도형 도서관 장애인서비스 분석과 시사점)

  • Yoon, Hee-Yoon
    • Journal of Korean Library and Information Science Society
    • /
    • v.53 no.2
    • /
    • pp.1-23
    • /
    • 2022
  • Access to knowledge and information is a universal human right. However, even after the Marrakesh Treaty was adopted on June 27, 2013, only 1-7% of standard printed materials are accessible to people with reading disabilities, including the visually impaired, and library services are very weak. As a result, the book famine of people with reading disabilities continues. This study, focusing on such severe access gaps and inequalities, analyzes Learning Ally and Bookshare in the US, the Royal National Institute of Blind People (RNIB) in the UK, Bibliothèque Numérique Francophone Accessible (BNFA) in France, and SAPIE in Japan, which are considered private organizations leading library services for the disabled in major developed countries. And based on the derived implications and the Marrakesh Treaty, a strategic plan was proposed to strengthen the services of the disabled in domestic libraries. It is urgent to enact the 'Act to Resolve Reading Barriers', amend the provisions related to the Copyright Act that restrict library services, strengthen the organizational capacity of the National Library for the Disabled, raise the service index for the disabled in library evaluation, and establish a library cooperation system centered on regional representative libraries and expand services, etc.

Comparative Analysis of the Characteristics of Natural Zeolites from Mongolia, Korea, and the United State (몽골, 한국, 미국 천연 제올라이트의 특성 비교 분석)

  • Battsetseg, Bayarsaikhan;Kim, Hu Sik;Kim, Young Hun;Kim, Jeong Jin;Lim, Woo Taik
    • Korean Journal of Mineralogy and Petrology
    • /
    • v.35 no.2
    • /
    • pp.141-151
    • /
    • 2022
  • The 16 natural zeolites collected from Mongolia (6 types), the United States (1 type), and Korea (9 types) were characterized by XRD, XRF, TGA, DTA, and CEC analysis. All 16 samples are composite minerals. Two or more mineral phases co-exist and consist primarily of minerals such as clinoptilolite, heulandite, mordenite, and chabazite. In certain samples, minerals like illite and quartz were present as impurities. The XRF analysis showed that the 16 natural zeolites contain SiO2, Al2O3, K2O, CaO, Na2O, MgO, and Fe2O3 oxides. The cation exchange capacity of the U-1 sample was 223.3 meg/100 g, which is higher than the rest of the samples. M-6 sample in Mongolian natural zeolite and K-1 sample in Korean natural zeolite showed the highest cation exchange capacity at 166.6 meg/100 g. As a result of thermal differential and thermos gravimetric analysis, all 16 samples showed excellent thermal stability up to 600℃.

Drone Obstacle Avoidance Algorithm using Camera-based Reinforcement Learning (카메라 기반 강화학습을 이용한 드론 장애물 회피 알고리즘)

  • Jo, Si-hun;Kim, Tae-Young
    • Journal of the Korea Computer Graphics Society
    • /
    • v.27 no.5
    • /
    • pp.63-71
    • /
    • 2021
  • Among drone autonomous flight technologies, obstacle avoidance is a very important technology that can prevent damage to drones or surrounding environments and prevent danger. Although the LiDAR sensor-based obstacle avoidance method shows relatively high accuracy and is widely used in recent studies, it has disadvantages of high unit price and limited processing capacity for visual information. Therefore, this paper proposes an obstacle avoidance algorithm for drones using camera-based PPO(Proximal Policy Optimization) reinforcement learning, which is relatively inexpensive and highly scalable using visual information. Drone, obstacles, target points, etc. are randomly located in a learning environment in the three-dimensional space, stereo images are obtained using a Unity camera, and then YOLov4Tiny object detection is performed. Next, the distance between the drone and the detected object is measured through triangulation of the stereo camera. Based on this distance, the presence or absence of obstacles is determined. Penalties are set if they are obstacles and rewards are given if they are target points. The experimennt of this method shows that a camera-based obstacle avoidance algorithm can be a sufficiently similar level of accuracy and average target point arrival time compared to a LiDAR-based obstacle avoidance algorithm, so it is highly likely to be used.

A LiDAR-based Visual Sensor System for Automatic Mooring of a Ship (선박 자동계류를 위한 LiDAR기반 시각센서 시스템 개발)

  • Kim, Jin-Man;Nam, Taek-Kun;Kim, Heon-Hui
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.28 no.6
    • /
    • pp.1036-1043
    • /
    • 2022
  • This paper discusses about the development of a visual sensor that can be installed in an automatic mooring device to detect the berthing condition of a vessel. Despite controlling the ship's speed and confirming its location to prevent accidents while berthing a vessel, ship collision occurs at the pier every year, causing great economic and environmental damage. Therefore, it is important to develop a visual system that can quickly obtain the information on the speed and location of the vessel to ensure safety of the berthing vessel. In this study, a visual sensor was developed to observe a ship through an image while berthing, and to properly check the ship's status according to the surrounding environment. To obtain the adequacy of the visual sensor to be developed, the sensor characteristics were analyzed in terms of information provided from the existing sensors, that is, detection range, real-timeness, accuracy, and precision. Based on these analysis data, we developed a 3D visual module that can acquire information on objects in real time by conducting conceptual designs of LiDAR (Light Detection And Ranging) type 3D visual system, driving mechanism, and position and force controller for motion tilting system. Finally, performance evaluation of the control system and scan speed test were executed, and the effectiveness of the developed system was confirmed through experiments.

A study on frost prediction model using machine learning (머신러닝을 사용한 서리 예측 연구)

  • Kim, Hyojeoung;Kim, Sahm
    • The Korean Journal of Applied Statistics
    • /
    • v.35 no.4
    • /
    • pp.543-552
    • /
    • 2022
  • When frost occurs, crops are directly damaged. When crops come into contact with low temperatures, tissues freeze, which hardens and destroys the cell membranes or chloroplasts, or dry cells to death. In July 2020, a sudden sub-zero weather and frost hit the Minas Gerais state of Brazil, the world's largest coffee producer, damaging about 30% of local coffee trees. As a result, coffee prices have risen significantly due to the damage, and farmers with severe damage can produce coffee only after three years for crops to recover, which is expected to cause long-term damage. In this paper, we tried to predict frost using frost generation data and weather observation data provided by the Korea Meteorological Administration to prevent severe frost. A model was constructed by reflecting weather factors such as wind speed, temperature, humidity, precipitation, and cloudiness. Using XGB(eXtreme Gradient Boosting), SVM(Support Vector Machine), Random Forest, and MLP(Multi Layer perceptron) models, various hyper parameters were applied as training data to select the best model for each model. Finally, the results were evaluated as accuracy(acc) and CSI(Critical Success Index) in test data. XGB was the best model compared to other models with 90.4% ac and 64.4% CSI, followed by SVM with 89.7% ac and 61.2% CSI. Random Forest and MLP showed similar performance with about 89% ac and about 60% CSI.

Design and Implementation of BNN based Human Identification and Motion Classification System Using CW Radar (연속파 레이다를 활용한 이진 신경망 기반 사람 식별 및 동작 분류 시스템 설계 및 구현)

  • Kim, Kyeong-min;Kim, Seong-jin;NamKoong, Ho-jung;Jung, Yun-ho
    • Journal of Advanced Navigation Technology
    • /
    • v.26 no.4
    • /
    • pp.211-218
    • /
    • 2022
  • Continuous wave (CW) radar has the advantage of reliability and accuracy compared to other sensors such as camera and lidar. In addition, binarized neural network (BNN) has a characteristic that dramatically reduces memory usage and complexity compared to other deep learning networks. Therefore, this paper proposes binarized neural network based human identification and motion classification system using CW radar. After receiving a signal from CW radar, a spectrogram is generated through a short-time Fourier transform (STFT). Based on this spectrogram, we propose an algorithm that detects whether a person approaches a radar. Also, we designed an optimized BNN model that can support the accuracy of 90.0% for human identification and 98.3% for motion classification. In order to accelerate BNN operation, we designed BNN hardware accelerator on field programmable gate array (FPGA). The accelerator was implemented with 1,030 logics, 836 registers, and 334.904 Kbit block memory, and it was confirmed that the real-time operation was possible with a total calculation time of 6 ms from inference to transferring result.

Review of 2020 Major Medical Decisions (2020년 주요 의료판결 분석)

  • Park, Nohmin;Jeong, Heyseung;Park, Taeshin;Yoo, Hyunjung;Lee, Jeongmin;Cho, Woosun
    • The Korean Society of Law and Medicine
    • /
    • v.22 no.2
    • /
    • pp.3-48
    • /
    • 2021
  • Among the major rulings handed down in 2020, there were cases involving anaphylaxis, which is timely as a side effect of coronavirus and flu vaccine. And as a rare case, a ruling was handed down that if medical treatment was done so unfaithfully beyond the limit of patience of ordinary people, it can be an independent illegal act and a cause of compensation for emotional distress. Also, there was a ruling in the appellate court that evaluated disability rate applying the Korean Academy of Medical Sciences Guides for the Evaluation of Permanent Impairment, not McBride system. And the supreme court made it clear that telemedicine is illegitimate. In relation to duty of explanation, it is in the process of adding detail criterion on the firm principles in the individual cases. In regard of medical records, there was a case that even when a medical record is strongly suspected to be tampered with, it is not considered to be an obstruction of proof. There were cases that resulted in different conclusion between the court of first instance and the appellate court rulings. Lastly, in the face of a growing number of cases in which doctors are sentenced to prison for malpractice, we reviewed a ruling that sentenced a doctor to prison.

Monitoring of Particulate Matter Concentration for Forage Crop Cultivation during Winter Season in Saemangeum (새만금 내 동계 사료작물 재배에 따른 미세먼지 농도 변화 모니터링)

  • Lee, Seong-Won;Kang, Bang-Hun;Seo, Il-Hwan
    • Journal of Bio-Environment Control
    • /
    • v.31 no.2
    • /
    • pp.114-124
    • /
    • 2022
  • The Saemangeum has a dry surface characteristic with a low moisture content ratio due to the saline and silt soil, so the vegetation cover is low compared to other areas. In areas with low vegetation cover, wind erosion has a high probability of scattering dust. If the vegetation cover is increased by cultivating crops that can withstand the Saemangeum reclaimed environment, scattering dust can be reduced by reducing the flow rate at the bottom. Thus, the purpose of this study is to analyze the effect of suppressing the generation of fine dust and scattering dust by cultivating winter forage crops on the Saemangeum reclaimed land. While growing 0.5 ha of barley and 0.5 ha of triticale in Saemangeum reclaimed land, the concentration of fine dust was monitored according to agricultural work and growth stage. Changes in the concentrations of PM-10, PM-2.5, and PM-1.0 were monitored on the leeward, the windward and centering on the crop field. As a result of monitoring, PM-1.0 had little effect on crop cultivation. the concentration of PM-10 and PM-2.5 increased according to tillage and harvesting, and tillage had a higher increasing the concentration of PM-10 and PM-2.5 than that of harvesting. According to the growth stage of crops, the effect of suppressing scattering dust was shown, and the effect of suppressing scattering dust was higher in the heading stage than in the seedling stage. So, it was found that there was an effect of suppressing scattering dust other than the effect of land covering. Through this study, it was possible to know about the generation and suppression effect of scattering dust according to crop cultivation.

Comparison of sample storage containers for the analysis of volatile organic compounds (VOC) (휘발성유기물(VOC) 분석을 위한 시료보관 용기의 비교)

  • Kim, Seokyung;Kim, Dalho
    • Analytical Science and Technology
    • /
    • v.35 no.3
    • /
    • pp.116-123
    • /
    • 2022
  • Polymer bags, metallic canisters, and glass bottles have been used as containers for analyzing the volatile organic compounds (VOCs) in air. In this study, various sampling containers were compared to investigate the short-term stability of VOCs, that is, from the time they are sampled to the time they are analyzed. Polyvinyl fluoride (PVF), polypropylene (PP), polyester aluminum (PE-Al) bags, canisters, and glass bottles were used as sample containers. A 100 nmol/mol standard gas mixture of benzene, toluene, ethylbenzene, m-xylene, styrene, and o-xylene was used for the VOC comparison. Changes in the concentrations of samples stored for 10~20 day in each container were measured using a thermal desorption-gas chromatograph-flame ionization detector (TD-GC-FID). As a result, VOCs stored in a canister and two kinds of amber glass bottles have shown immaterial decreases in concentration in one week, and more than 80 % of the initial concentration was maintained for two weeks. In the case of polymer bags, the concentration of all VOCs, except benzene and toluene, were remarkably decreased below 70% of the initial concentration in one day. Particularly, ethylbenzene, xylene, and styrene have shown dramatic decreases in concentration below 30 % of the initial concentration in all polymer bags in one day.