• Title/Summary/Keyword: Real part

Search Result 2,734, Processing Time 0.034 seconds

Experimental Investigation of Combined Sinusoidal Loads to Simulate Soil Liquefaction Triggering under Real Earthquake Loads (실지진하중 하에서의 지반 액상화 발생을 모사하기 위한 조합 정현하중에 대한 실험적 고찰)

  • Choi, Jae Soon;Baek, Woo Hyun
    • Journal of Korean Society of Disaster and Security
    • /
    • v.11 no.2
    • /
    • pp.29-35
    • /
    • 2018
  • This study is an experimental comparison on the fact that the sinusoidal load, which has been used so far in the laboratory cyclic test, which is an important part of the liquefaction triggering study, is somewhat different from the phenomenon that causes the soil liquefaction during the earthquake loading. To this end, this study proposes a new type of combined sinusoidal load and compares it with experimental results to load the conventional sine wave. In the comparison, the shaking table tests were carried out and the sample in the tests was remolded with the relative density of 40%, which is a condition where liquefaction is easy to occur. Firstly, the conventional cyclic test was carried out under the condition that with the amplitude of sine wave was 0.3 g. Additionally, 3 types of tests were performed using the combination loads made up with 0.03 g sinusoidal load and 0.3g sinusoidal load. At that time, the loading time for the first sinusoidal load were changed with 5 seconds, 10 seconds, and 15 seconds. As a result, the test with the conventional sine wave and the test with the first sinusoidal loading for 5 seconds showed that the change of the pore water pressure gradually increased. But in the tests with the combined sinusoidal load which changed the first sinusoidal loading time with 10 and 15 seconds, it was found that the pore water pressure suddenly rose at a certain instant and liquefaction occurs. From the experimental comparison, it is judged that it is appropriate that the time of the first sine wave is over 10 seconds at the proposed combined load for the soil condition with relative density 40%.

A Development of a Mixed-Reality (MR) Education and Training System based on user Environment for Job Training for Radiation Workers in the Nondestructive Industry (비파괴산업 분야 방사선작업종사자 직장교육을 위한 사용자 환경 기반 혼합현실(MR) 교육훈련 시스템 개발)

  • Park, Hyong-Hu;Shim, Jae-Goo;Park, Jeong-kyu;Son, Jeong-Bong;Kwon, Soon-Mu
    • Journal of the Korean Society of Radiology
    • /
    • v.15 no.1
    • /
    • pp.45-54
    • /
    • 2021
  • This study was written to create educational content in non-destructive fields based on Mixed Reality. Currently, in the field of radiation, there is almost no content for educational Mixed Reality-based educational content. And in the field of non-destructive inspection, the working environment is poor, the number of employees is often 10 or less for each manufacturer, and the educational infrastructure is not built. There is no practical training, only practical training and safety education to convey information. To solve this, it was decided to develop non-destructive worker education content based on Mixed Reality. This content was developed based on Microsoft's HoloLens 2 HMD device. It is manufactured based on the resolution of 1280 ⁎ 720, and the resolution is different for each device, and the Side is created by aligning the Left, Right, Bottom, and TOP positions of Anchor, and the large image affects the size of Atlas. The large volume like the wallpaper and the upper part was made by replacing it with UITexture. For UI Widget Wizard, I made Label, Buttom, ScrollView, and Sprite. In this study, it is possible to provide workers with realistic educational content, enable self-directed education, and educate with 3D stereoscopic images based on reality to provide interesting and immersive education. Through the images provided in Mixed Reality, the learner can directly operate things through the interaction between the real world and the Virtual Reality, and the learner's learning efficiency can be improved. In addition, mixed reality education can play a major role in non-face-to-face learning content in the corona era, where time and place are not disturbed.

A Study on the Painting's Aesthetic of Gongjae Yoon Duseo (공재(恭齋) 윤두서(尹斗緖)의 회화심미(繪畵審美) 고찰)

  • Kim, Doyoung
    • The Journal of the Convergence on Culture Technology
    • /
    • v.7 no.1
    • /
    • pp.175-183
    • /
    • 2021
  • Gongjae Yoon DuSeo(1668~1715), from Haenam in the late Joseon Dynasty, is a scholar-born painter who was active during King Sukjong. He is the person who created the foundation as a pioneer of realist paintings in the late Joseon period during the transition from the middle to the latter period. He was born in Namin's prestigious family, but he ended his career as part of a partisan fight and immersed himself in painting and learning. 18C, the beginning of the late Joseon Dynasty, was a period when Silhak emerged and the Jinkyung era opened with awareness of nationalism. At this time, by incorporating the Silhak thought into the art world, the real reformed aesthetic consciousness was demonstrated to pioneer common people's customs, the application of Western painting methods, the pursuit of realist techniques, and the introduction of Namjongmuninhwa. His view of painting, who thoroughly learned the old things and pursued change, must have both the form and spirit that he can achieve 'HwaDo' only when it has the science of 'learning and knowledge' and the technical elements of 'practice and quality' emphasized. He has worked in a variety of reconciliations. In particular, portrait paintings are characterized by ihyeongsasin's realistic expressions of aesthetics. His masterpiece, 「Self-portrait」, excels in extreme-realistic depiction and innovation in composition, and stands out with an unconventional experimentation spirit that expresses his mind and thoughts in a painting with a sense of resentment. His landscape paintings combine to express the form as it is and mental notions, and beautifully embodied Do as a form, thus achieving ihyeongmido, which reached the level of'joyfulness forgotten even the heart of joy'. On the other hand, the generalization of the common people using various common people's lives as the subject of an open-mindedness aimed at gaining the facts of ihyeongsajin, a passive protest against corrupt power and an expression of a spirit of love. Since then, his painting style has been passed down from generation to generation to his eldest son Yoon Deok-hee and his grandson Yoon Yong, leading the change and revival of calligraphy art in the late Joseon Dynasty.

A Study on Landscape of Cheongpunggye (청풍계(淸風溪) 경관에 관한 연구)

  • Lee, Jin-Hyang;Lee, Jae-Keun
    • Journal of the Korean Institute of Traditional Landscape Architecture
    • /
    • v.29 no.1
    • /
    • pp.50-58
    • /
    • 2011
  • Cheongpunggye is located in a valley where Baekaksan, the main mountain of Seoul and Inwang Mountain corresponding to right-white tiger(石白虎) divination based on topography are crossed. The owner of Cheongpunggye is Seonwon Kim Sangyong and many people had visited there without pause because of beautiful landscape since the early times of Chosun. Seonwon Kim Sangyong had ever studied together with Yulgok Yi I and Woogye Seong Hon. He was one of the Western faction(Seo-in) which was the leading power of Injo Coup and died for his chastity during Second Manchu Invasion of Chosun. He is known as a model of fidelity which is a symbol for scholar's spirit in Chosun together with his younger brother Cheongeum Kim Sangheon. Jangdong region, the clan village of New Andong family was the birthplace of Yulgok School which was the fundamental of scholar spirit of Chosun. And Jangdong would be the source of Jin-Gyeong(Real Scenery) Culture which was bloomed by Baekak club composed of Gyeomjae Jeong Seon, Sacheon Lee Byeongyeon, and Gwanajae Cho Yeongseok. The contents of this study are as follows. First, this study explored the placeness of Seochon region through the historical background like the relation between Jangdong, the clan village of Andong Kim family and Andong Kim family, and achievements of Seonwon Kim Sangyong and circumstances of that times. Second, this study tried to know original landscape of Cheongpunggye by investigating location, topography, water system etc. based on analysis of literature, old map, and paintings describing Cheongpunggye. The study was progressed in this way. To infer the original landscape, about 50 landscape elements of Cheongpunggye shown in Punggyejibseunggi(楓溪集勝記), Cheongpunggye Cheop, Cheongpunggye(淸風溪), the work of Gyeomjae Jeong Sean were searched, and then the location and form of the elements was analyzed. Furthermore, by analyzing the meanings of the names for the landscape elements, the thoughts(Naturalism, Taoism, Confucianism, Buddhism) supporting the structure of Cheongpunggye could be inferred. It is thought that these findings can contribute to exploration of placeness of Cheongpunggye. The study on original landscape of Cheongpunggye can be used as basic data when these works are executed-revival of Cheongpunggye, restoration of small streams in upper part of Cheonggyecheon, renewal of Seochon region.

Stand-alone Real-time Healthcare Monitoring Driven by Integration of Both Triboelectric and Electro-magnetic Effects (실시간 헬스케어 모니터링의 독립 구동을 위한 접촉대전 발전과 전자기 발전 원리의 융합)

  • Cho, Sumin;Joung, Yoonsu;Kim, Hyeonsu;Park, Minseok;Lee, Donghan;Kam, Dongik;Jang, Sunmin;Ra, Yoonsang;Cha, Kyoung Je;Kim, Hyung Woo;Seo, Kyoung Duck;Choi, Dongwhi
    • Korean Chemical Engineering Research
    • /
    • v.60 no.1
    • /
    • pp.86-92
    • /
    • 2022
  • Recently, the bio-healthcare market is enlarging worldwide due to various reasons such as the COVID-19 pandemic. Among them, biometric measurement and analysis technology are expected to bring about future technological innovation and socio-economic ripple effect. Existing systems require a large-capacity battery to drive signal processing, wireless transmission part, and an operating system in the process. However, due to the limitation of the battery capacity, it causes a spatio-temporal limitation on the use of the device. This limitation can act as a cause for the disconnection of data required for the user's health care monitoring, so it is one of the major obstacles of the health care device. In this study, we report the concept of a standalone healthcare monitoring module, which is based on both triboelectric effects and electromagnetic effects, by converting biomechanical energy into suitable electric energy. The proposed system can be operated independently without an external power source. In particular, the wireless foot pressure measurement monitoring system, which is rationally designed triboelectric sensor (TES), can recognize the user's walking habits through foot pressure measurement. By applying the triboelectric effects to the contact-separation behavior that occurs during walking, an effective foot pressure sensor was made, the performance of the sensor was verified through an electrical output signal according to the pressure, and its dynamic behavior is measured through a signal processing circuit using a capacitor. In addition, the biomechanical energy dissipated during walking is harvested as electrical energy by using the electromagnetic induction effect to be used as a power source for wireless transmission and signal processing. Therefore, the proposed system has a great potential to reduce the inconvenience of charging caused by limited battery capacity and to overcome the problem of data disconnection.

Water Digital Twin for High-tech Electronics Industrial Wastewater Treatment System (II): e-ASM Calibration, Effluent Prediction, Process selection, and Design (첨단 전자산업 폐수처리시설의 Water Digital Twin(II): e-ASM 모델 보정, 수질 예측, 공정 선택과 설계)

  • Heo, SungKu;Jeong, Chanhyeok;Lee, Nahui;Shim, Yerim;Woo, TaeYong;Kim, JeongIn;Yoo, ChangKyoo
    • Clean Technology
    • /
    • v.28 no.1
    • /
    • pp.79-93
    • /
    • 2022
  • In this study, an electronics industrial wastewater activated sludge model (e-ASM) to be used as a Water Digital Twin was calibrated based on real high-tech electronics industrial wastewater treatment measurements from lab-scale and pilot-scale reactors, and examined for its treatment performance, effluent quality prediction, and optimal process selection. For specialized modeling of a high-tech electronics industrial wastewater treatment system, the kinetic parameters of the e-ASM were identified by a sensitivity analysis and calibrated by the multiple response surface method (MRS). The calibrated e-ASM showed a high compatibility of more than 90% with the experimental data from the lab-scale and pilot-scale processes. Four electronics industrial wastewater treatment processes-MLE, A2/O, 4-stage MLE-MBR, and Bardenpo-MBR-were implemented with the proposed Water Digital Twin to compare their removal efficiencies according to various electronics industrial wastewater characteristics. Bardenpo-MBR stably removed more than 90% of the chemical oxygen demand (COD) and showed the highest nitrogen removal efficiency. Furthermore, a high concentration of 1,800 mg L-1 T MAH influent could be 98% removed when the HRT of the Bardenpho-MBR process was more than 3 days. Hence, it is expected that the e-ASM in this study can be used as a Water Digital Twin platform with high compatibility in a variety of situations, including plant optimization, Water AI, and the selection of best available technology (BAT) for a sustainable high-tech electronics industry.

Performance Prediction for an Adaptive Optics System Using Two Analysis Methods: Statistical Analysis and Computational Simulation (통계분석 및 전산모사 기법을 이용한 적응광학 시스템 성능 예측)

  • Han, Seok Gi;Joo, Ji Yong;Lee, Jun Ho;Park, Sang Yeong;Kim, Young Soo;Jung, Yong Suk;Jung, Do Hwan;Huh, Joon;Lee, Kihun
    • Korean Journal of Optics and Photonics
    • /
    • v.33 no.4
    • /
    • pp.167-176
    • /
    • 2022
  • Adaptive optics (AO) systems compensate for atmospheric disturbance, especially phase distortion, by introducing counter-wavefront deformation calculated from real-time wavefront sensing or prediction. Because AO system implementations are time-consuming and costly, it is highly desirable to estimate the system's performance during the development of the AO system or its parts. Among several techniques, we mostly apply statistical analysis, computational simulation, and optical-bench tests. Statistical analysis estimates performance based on the sum of performance variances due to all design parameters, but ignores any correlation between them. Computational simulation models every part of an adaptive optics system, including atmospheric disturbance and a closed loop between wavefront sensor and deformable mirror, as close as possible to reality, but there are still some differences between simulation models and reality. The optical-bench test implements an almost identical AO system on an optical bench, to confirm the predictions of the previous methods. We are currently developing an AO system for a 1.6-m ground telescope using a deformable mirror that was recently developed in South Korea. This paper reports the results of the statistical analysis and computer simulation for the system's design and confirmation. For the analysis, we apply the Strehl ratio as the performance criterion, and the median seeing conditions at the Bohyun observatory in Korea. The statistical analysis predicts a Strehl ratio of 0.31. The simulation method similarly reports a slightly larger value of 0.32. During the study, the simulation method exhibits run-to-run variation due to the random nature of atmospheric disturbance, which converges when the simulation time is longer than 0.9 seconds, i.e., approximately 240 times the critical time constant of the applied atmospheric disturbance.

SSI Education and Scientific Literacy from a Lifelong Learning Perspective (평생학습적 시각을 통해 바라본 SSI 교육과 과학적 소양)

  • Park, Shin-Hee;Kim, Chan-Jong
    • Journal of The Korean Association For Science Education
    • /
    • v.42 no.1
    • /
    • pp.61-75
    • /
    • 2022
  • Recently, lifelong learning ability was newly proposed as scientific literacy, the goal of the science curriculum. To solve various science-related problems students encounter in life, lifelong learning abilities related to science beyond school science education are required, but empirical evidence shows that students can solve problems they actually face through scientific literacy. It is not easy to find in the existing science education research. In addition, there is a lack of discussion on how to cultivate lifelong learning ability suggested in the curriculum through school science education. In this study, attention was paid to SSI education as a method for students to cultivate lifelong learning ability through school science education and to develop their ability to solve science-related problems encountered in life. In this context, statements in the existing SSI education studies were reviewed to discover discourses related to lifelong learning, and their types and characteristics were distinguished. It was possible to confirm lifelong learning and its applicability with focus on science education research through this. For the study, 18 literature materials on the subject of SSI education were selected, and the discourses related to lifelong learning in the SSI education research were discovered by examining the statements revealed in the data. As a result of the study, there are four categories of discourses related to lifelong learning: 'awareness of science,' 'connection between science and everyday life', 'promotion of participatory citizenship', and 'construction of identity'. Various SSI education studies have already had lifelong learning perception in various contexts, and the four types of discourses related to lifelong learning could be linked to the four types of learning presented in the UNESCO Lifelong Learning Report. SSI education tends to view students' life experiences as part of their learning and aims to help students develop the character and capacity to make responsible decisions on social issues related to science and put them into practice. This competency can be continuously connected to the real-life of students outside of school as a lifelong learning ability. This study requires expanding the discourse related to lifelong learning in science education and operating and managing the overall educational system to foster students' lifelong learning ability.

The Trend of Cigarette Design and Tobacco Flavor System Development

  • Wu, Jimmy Z.
    • Journal of the Korean Society of Tobacco Science
    • /
    • v.24 no.1
    • /
    • pp.67-73
    • /
    • 2002
  • In light of addressing consumer health concern, coping with anti-tobacco movement, and promoting new product, tobacco industry is actively pursuing to make a new generation of cigarettes with low tar and nicotine deliveries, and less harmful substances. Low tar and low nicotine cigarettes increases their market shares dramatically world wide, especially in KT&G, multinational tobacco companies, EU countries, even in China regulated by CNTC to set up yearly target to lower tar and nicotine deliveries. On the other hand, to design a new cigarette with reduced harmful substances begins to gain speed. The "modified Hoffmann list" publishes thirty plus substances in tobacco leaf and main smoke stream, which is the prime suspect causing health problems. Various ways and means are developed to reduce such components including new tobacco breeds, new curing method, tobacco leaf treatment before processing, selected filtration system, innovated casing system to reduce free radicals, as well as some non conventional cigarette products. In TSRC held this year, the main topic is related to reduce tobacco specific nitrosamines in tobacco leaf. The new generation of cigarette is in the horizon. It still needs a lot help to produce commercial products with satisfied taste and aroma characters. The flavor industry is not regulated by many governments demanding which ingredients might or might not be for tobacco use. However, most of the cigarette companies self impose a list of ingredients to guide flavor suppliers to design flavors. Unfortunately, the number of ingredients in those lists is getting shorter every year. It is understandable that the health is not the only reason. Some cigarette companies are playing safe to protect the company from potential lawsuit, while others are just copying from their competitors. Moreover, it is obvious that it needs more assistance from casings and flavors to design new generation of cigarettes with missing certain flavor components in tobacco leaf and main smoke stream. These flavor components are either non-existed or at lower level at new form of cured tobacco leaf or filtered in the main smoke stream along with reduced harmful substances. The use of carbon filters and other selected filtration system poses another tough task for flavor system design. Specific flavor components are missing from the smoke analysis data, which brings a notion of "carbon taste" and "dryness" of mouth feel. It is ever more demanded by cigarette industry to flavor suppliers to produce flavors as body enhancer, tobacco notes, salivating agents, harshness reducer, and various of aromatic notes provided they are safe to use. Another trend is that water based flavor or flavor with reduced ethanol as solvent is gaining popularity. It is preferred by some cigarette companies that the flavor is compounded with all natural ingredients or all ingredients should he GMO free. The new generation of cigarettes demands many ways of new thinking process. It is also vital for tobacco industry. It reflects the real needs for the consumers that the cigarette product should be safe to use as well as bearing the taste and aroma characters smokers always enjoyed. An effective tobacco flavor system is definitely a part of the equation. The global trend of tobacco industry is like trends of any other industries lead by consumer needs, benefited with new technology availability, affected by the global economy, and subjected for various rules and regulations. Anti-tobacco organizations and media exceptionally scrutinize cigarette, as a legal commercial product. Cigarette is probably the most studied commercial product for its composition, structure, deliveries, effects, as well as its new developmental trend. Therefore, any new trend of cigarette development would be within these boundaries. This paper is trying to point out what it would be like for tobacco industry in the next few yews and what concerns the tobacco industry. It focuses mostly on the efforts to produce safer cigarettes. It is such a vital task for the tobacco industry and its affiliate industries such as cigarette papers, filters, flavors, and other materials. The facts and knowledge presented in this paper might be well known for the public. Some of the comments and predictions are very much personal opinion for a further discussion.

A Study on the Support System for Reinforcement of Competitiveness of Small Business persons - Mainly Focused on Support System for Small Business Persons - (소상공인 경쟁력 강화의 지원제도에 관한 연구 - 소상공인 지원제도를 중심으로 -)

  • Woo, Dae-IL;Lee, Sang-Youn
    • The Korean Journal of Franchise Management
    • /
    • v.2 no.2
    • /
    • pp.95-110
    • /
    • 2011
  • As global economic conditions are getting uneasy and polarization of our economy is intensified, the economic sentiment of small businesses is still low and unstable. The collapse of worldwide banking systems due to sub prime crisis in 2007 became the catalyst that shakes financial industries in each country in the world; the most sentiment people, small businesspersons, also have hard time facing survival way out, facing a great crisis. All organizing powers including manufactures, wholesales and retails are being gradually greater in mutual relations and dependence, and unstable factors about risks are also increasing. For exterior environmental and physical risk factors which cannot make small businesses survive themselves by developing ways out are eventually increasing, those who cannot cope with these factors face a great crisis. Although the government tries hard to overcome this situation conducting many ways, the effect does not continue. It is the real state that independent business markets including overall employment and establishing business have vicious cycle that they cannot be improved, due to increase of employment centered on short-term labors which lack durability in creation of employment and decline of household income. Recently, growth shows indication of slowdown because of multinational risk factors including financial crisis in each country in Europe, the death of Kim Jung-il, relationship with North Korea, and unstability of war situation in the Middle East Asia. Experts expect that growth rate will be about 4%, and independent business that ordinary people feel is still gloomy. It's reality that there is no adequate alternative for lack of jobs, unstable employment and a means of living after retirement. Also, the fact that large companies enter the market which is narrow and in the excessive competition should be an environmental factor that makes the situation worse. The business concept, a franchise, is the part we should think about whether it is the institutional solution that can guarantee independent businessmen stable life. Major companies are frightfully entering the market today, breaking the barrier to entry and shouting of a win-win with independent businesses. It's the small businesspersons who go through painful domestic recession, cannot predict the future and manage confusing and unstable independent business. It's very important to restore the domestic economy through wisely boosting consumption as soon as possible. It's also important to lead the situation by gathering powers of the government and related organizations, agonizing, suggesting solutions, and establishing accurate directions. The purpose of this study, therefore, is to suggest ways to strengthen competitiveness of small businesspersons by examining small business support policies which are currently implemented.