• Title/Summary/Keyword: 접촉기법

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Analysis of the Risk of Heat Generation due to Bolt Loosening in Terminal Block Connector Parts (볼트풀림에 의한 터미널 블록의 접속부 발열 위험성 분석)

  • Yeon, Yeong-Mo;Kim, Seung-Hee
    • Fire Science and Engineering
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    • v.34 no.3
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    • pp.67-75
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    • 2020
  • In this study, the risk of heat generation due to normal and overload currents that vary with the abnormal loosening angle of wire-connecting bolts were identified. The risks were analyzed based on the thermal characteristics to minimize the carbonization accidents of terminal blocks inside distribution panels typically used in industrial sites. We applied a method for measuring the heating temperature and temperature variations in the terminal blocks in real-time by installing a resistance temperature detector sensor board in the terminal block. The experimental results showed that the terminal block model with a low-rated current exhibited a higher heating temperature, thus, confirming the need to select the terminal block capacity based on load currents. Additionally, the higher the rated current of the terminal block with a high-rated current and the higher the degree of loosening, the faster the carbonization point. Such heating temperature monitoring enabled real-time thermal temperature measurement and a step-by-step risk level setting through thermal analysis. The results of the measurement and analysis of carbonization risks can provide a theoretical basis for further research regarding the risk of fire due to carbonization. Furthermore, the deterioration measurement method using the temperature sensor board developed in this study is widely applicable to prevent fires caused by poor electrical contact as well as risk-level management.

Parametric Study of Dynamic Soil-pile-structure Interaction in Dry Sand by 3D Numerical Model (3차원 수치 모델을 이용한 건조사질토 지반-말뚝-구조물 동적 상호작용의 매개변수 연구)

  • Kwon, Sun-Yong;Yoo, Min-Taek
    • Journal of the Korean Geotechnical Society
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    • v.32 no.9
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    • pp.51-62
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    • 2016
  • Parametric studies for various site conditions by using 3d numerical model were carried out in order to estimate dynamic behavior of soil-pile-structure system in dry soil deposits. Proposed model was analyzed in time domain using FLAC3D which is commercial finite difference code to properly simulate nonlinear response of soil under strong earthquake. Mohr-Coulomb criterion was adopted as soil constitutive model. Soil nonlinearity was considered by adopting the hysteretic damping model, and an interface model which can simulate separation and slip between soil and pile was adopted. Simplified continuum modeling was used as boundary condition to reduce analysis time. Also, initial shear modulus and yield depth were appropriately determined for accurate simulation of system's nonlinear behavior. Parametric study was performed by varying weight of superstructure, pile length, pile head fixity, soil relative density with proposed numerical model. From the results of parametric study, it is identified that inertial force induced by superstructure is dominant on dynamic behavior of soil-pile-structure system and effect of kinematic force induced by soil movement was relatively small. Difference in dynamic behavior according to the pile length and pile head fixity was also numerically investigated.

Characteristics of Wastewater from the Pulp.Paper Industry and its Biological Treatment Technologies (펄프.제지산업(製紙産業) 폐수(廢水)의 특성(特性)과 생물학적(生物學的) 처리기술(處理技術))

  • Abn, Ji-Whan;Lim, Mi-Hee
    • Resources Recycling
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    • v.18 no.2
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    • pp.16-29
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    • 2009
  • This paper describes characteristics of pollutants in wastewater from the pulp and paper industry and biological technologies for the wastewater treatment. The wastewater from the pulp and paper industry contains high concentrations of biochemical oxygen demand (BOD) and chemical oxygen demand (COD) and shows high toxicity and strong black-brown color. In particular, organic chlorinated compounds such as dioxins and furans may be formed by the chlorination of lignin in wood chips. Thus the pulp and paper industry is recently trending toward total chlorine-free (TCF) bleaching processes. All biological technologies for pulp and paper wastewater treatment are based on the contact between wastewater and bacteria, which feed on organic materials in the wastewater, thus they reduce BOD concentration in it. Both aerobic and anaerobic treatments were found to be effective for the wastewater treatment. Furthermore, advanced technologies such as fungal application and combined biological-filtration process have been also introduced to the wastewater treatment field. These technologies would be useful for water recycling to reduce water consumption throughout pulp and paper making process.

Design and Implementation of CW Radar-based Human Activity Recognition System (CW 레이다 기반 사람 행동 인식 시스템 설계 및 구현)

  • Nam, Jeonghee;Kang, Chaeyoung;Kook, Jeongyeon;Jung, Yunho
    • Journal of Advanced Navigation Technology
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    • v.25 no.5
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    • pp.426-432
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    • 2021
  • Continuous wave (CW) Doppler radar has the advantage of being able to solve the privacy problem unlike camera and obtains signals in a non-contact manner. Therefore, this paper proposes a human activity recognition (HAR) system using CW Doppler radar, and presents the hardware design and implementation results for acceleration. CW Doppler radar measures signals for continuous operation of human. In order to obtain a single motion spectrogram from continuous signals, an algorithm for counting the number of movements is proposed. In addition, in order to minimize the computational complexity and memory usage, binarized neural network (BNN) was used to classify human motions, and the accuracy of 94% was shown. To accelerate the complex operations of BNN, the FPGA-based BNN accelerator was designed and implemented. The proposed HAR system was implemented using 7,673 logics, 12,105 registers, 10,211 combinational ALUTs, and 18.7 Kb of block memory. As a result of performance evaluation, the operation speed was improved by 99.97% compared to the software implementation.

News Article Analysis of the 4th Industrial Revolution and Advertising before and after COVID-19: Focusing on LDA and Word2vec (코로나 이전과 이후의 4차 산업혁명과 광고의 뉴스기사 분석 : LDA와 Word2vec을 중심으로)

  • Cha, Young-Ran
    • The Journal of the Korea Contents Association
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    • v.21 no.9
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    • pp.149-163
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    • 2021
  • The 4th industrial revolution refers to the next-generation industrial revolution led by information and communication technologies such as artificial intelligence (AI), Internet of Things (IoT), robot technology, drones, autonomous driving and virtual reality (VR) and it also has made a significant impact on the development of the advertising industry. However, the world is rapidly changing to a non-contact, non-face-to-face living environment to prevent the spread of COVID 19. Accordingly, the role of the 4th industrial revolution and advertising is changing. Therefore, in this study, text analysis was performed using Big Kinds to examine the 4th industrial revolution and changes in advertising before and after COVID 19. Comparisons were made between 2019 before COVID 19 and 2020 after COVID 19. Main topics and documents were classified through LDA topic model analysis and Word2vec, a deep learning technique. As the result of the study showed that before COVID 19, policies, contents, AI, etc. appeared, but after COVID 19, the field gradually expanded to finance, advertising, and delivery services utilizing data. Further, education appeared as an important issue. In addition, if the use of advertising related to the 4th industrial revolution technology was mainstream before COVID 19, keywords such as participation, cooperation, and daily necessities, were more actively used for education on advanced technology, while talent cultivation appeared prominently. Thus, these research results are meaningful in suggesting a multifaceted strategy that can be applied theoretically and practically, while suggesting the future direction of advertising in the 4th industrial revolution after COVID 19.

A Big Data Based Random Motif Frequency Method for Analyzing Human Proteins (인간 단백질 분석을 위한 빅 데이타 기반 RMF 방법)

  • Kim, Eun-Mi;Jeong, Jong-Cheol;Lee, Bae-Ho
    • The Journal of the Korea institute of electronic communication sciences
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    • v.13 no.6
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    • pp.1397-1404
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    • 2018
  • Due to the technical difficulties and high cost for obtaining 3-dimensional structure data, sequence-based approaches in proteins have not been widely acknowledged. A motif can be defined as any segments in protein or gene sequences. With this simplicity, motifs have been actively and widely used in various areas. However, the motif itself has not been studied comprehensively. The value of this study can be categorized in three fields in order to analyze the human proteins using artificial intelligence method: (1) Based on our best knowledge, this research is the first comprehensive motif analysis by analyzing motifs with all human proteins in Protein Data Bank (PDB) associated with the database of Enzyme Commission (EC) number and Structural Classification of Proteins (SCOP). (2) We deeply analyze the motif in three different categories: pattern, statistical, and functional analysis of clusters. (3) At the last and most importantly, we proposed random motif frequency(RMF) matric that can efficiently distinct the characteristics of proteins by identifying interface residues from non-interface residues and clustering protein functions based on big data while varying the size of random motif.

A Study for Comparison of Geometric Characteristics on Forearms for Improvement of Convinience in Splint Manufacturing with 3D Printing Technology (3D 프린팅 기술을 적용한 스플린트의 제작 용이성 향상을 위한 아래팔 기하 정보 비교에 관한 연구)

  • Chang, Ji Hong
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.12 no.5
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    • pp.475-481
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    • 2019
  • A splint is one of assisting devices for the disabled with hemiplegia or contracture and is manually made by an experienced expert. Heated thermoplastic materials are continuously fitted to the affected part. This traditional method has a possible risk of low-temperature burn, quality variance of the splint due to the proficiency of maker. etc. While various approaches has been made using 3D printing technology in order to redeem those disadvantages, they still carry high cost issues with 3D scanners or accuracy issues with manual measurement. This research begins with symmetrical characteristics of human body and focuses on the preliminary study for the possibility of splint manufacturing with 3D printing technology based on geometric characteristics of unaffected arm. 3D right and left forearm models of healthy male adults were created by photogrammetry software and a series of digital images in order to measure the circumference and cross-sectional area of the forearm models at every 20mm from the elbow. The circumference and cross-sectional area showed tolerable levels of differences between both sides within subjects; The circumference and cross-sectional area showed very strong correlations between both sides within subjects. From these findings, the possibility of splint manufacturing with 3D printing technology could be confirmed based on the geometric characteristics of unaffected side.

Seismic Soil-Structure Interaction Analyses of LNG Storage Tanks Depending on Foundation Type (기초 형식에 따른 LNG 저장탱크의 지반-구조물 상호작용을 고려한 지진응답 분석)

  • Son, Il-Min;Kim, Jae-Min;Lee, Changho
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.32 no.3
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    • pp.155-164
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    • 2019
  • In this study, the soil-structure interaction(SSI) effect on the seismic response of LNG storage tanks was investigated according to the type of foundation. For this purpose, a typical of LNG storage tank with a diameter of 71m, which is constructed on a 30m thick clay layer over bedrock was selected, and nonlinearity of the soil was taken into account by the equivalent linearization method. Four different types of foundations including shallow foundation, piled raft foundation, and pile foundations(surface and floating types) were considered. In addition, the effect of soil compaction in group piles on seismic response of the tank was investigated. The KIESSI-3D, which is a SSI analysis package in the frequency domain, was used for the SSI analysis. Stresses in the outer tank, and base shear and overturning moment in the inner tank were calculated. From the comparisons, the following conclusions could be made: (1) Conventional fixed base seismic responses of outer tank and inner tank can be much larger than those of considering the SSI effect; (2) The influence of SSI on the dynamic response of the inner tank and the outer tank depends on the foundation types; and (3) Change in the seismic response of the structure by soil compaction in the piled raft foundation is about 10% and its effect is not negligible in the seismic design of the structure.

Pupil Data Measurement and Social Emotion Inference Technology by using Smart Glasses (스마트 글래스를 활용한 동공 데이터 수집과 사회 감성 추정 기술)

  • Lee, Dong Won;Mun, Sungchul;Park, Sangin;Kim, Hwan-jin;Whang, Mincheol
    • Journal of Broadcast Engineering
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    • v.25 no.6
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    • pp.973-979
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    • 2020
  • This study aims to objectively and quantitatively determine the social emotion of empathy by collecting pupillary response. 52 subjects (26 men and 26 women) voluntarily participated in the experiment. After the measurement of the reference of 30 seconds, the experiment was divided into the task of imitation and spontaneously self-expression. The two subjects were interacted through facial expressions, and the pupil images were recorded. The pupil data was processed through binarization and circular edge detection algorithm, and outlier detection and removal technique was used to reject eye-blinking. The pupil size according to the empathy was confirmed for statistical significance with test of normality and independent sample t-test. Statistical analysis results, the pupil size was significantly different between empathy (M ± SD = 0.050 ± 1.817)) and non-empathy (M ± SD = 1.659 ± 1.514) condition (t(92) = -4.629, p = 0.000). The rule of empathy according to the pupil size was defined through discriminant analysis, and the rule was verified (Estimation accuracy: 75%) new 12 subjects (6 men and 6 women, mean age ± SD = 22.84 ± 1.57 years). The method proposed in this study is non-contact camera technology and is expected to be utilized in various virtual reality with smart glasses.

A Study on Typology and the Casual factors of Elderly-abuse (노인학대 유형화 및 유형결정요인 연구)

  • Lee, Yun-Kyung;Kim, Mee-Hye
    • 한국노년학
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    • v.28 no.4
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    • pp.1165-1178
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    • 2008
  • The objectives of this study are developing the new types of elderly abuse and finding the variables affecting the new elderly abuse type. And This is at suggesting the intervention strategies preventing the elderly abuse. The 350 cases of elderly abuse reported in Elder Protection Agency was analysed. Data is analyzed by using statistical techniques including cluster analysis and logit-regression. New type of elderly abuse is "violent elderly abuse" and "avoiding elderly abuse". Violent elderly abuse is very connected with directly violence speech and behavior and avoiding elderly abuse is connected with neglect and abandonment, self-neglect. The elderly's instrumental activity of daily living and education, the offender's sex and education and living together type of the elderly - the offender, and the offender's care burden are the casual factors of the new type of elderly abuse. Based on the results, the various service programmes for the abused elderly is developed and implemented.