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Development of particle focusing device to monitor various low pressure processes (다양한 조건의 저압 공정 모니터링을 위한 입자 집속 장치 개발)

  • Kim, Myungjoon;Kim, Dongbin;Kang, Sang-Woo;Kim, Taesung
    • Particle and aerosol research
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    • v.13 no.2
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    • pp.53-63
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    • 2017
  • As semiconductor process was highly integrated, particle contamination became a major issue. Because particle contamination is related with process yields directly, particles with a diameter larger than half pitch of gate should be controlled. PBMS (Particle beam mass spectrometry) is one of powerful nano particle measurement device. It can measure 5~500 nm particles at ~ 100 mtorr condition in real time by in-situ method. However its usage is restricted to research filed only, due to its big device volume and high price. Therefore aperture changeable aerodynamic lenses (ACALs) which can control particle focusing characteristics by changing its aperture diameter was proposed in this study. Unlike conventional aerodynamic lenses which changes particle focusing efficiency when operating condition is changed, ACALs can maintain particle focusing efficiency. Therefore, it can be used for a multi-monitoring system that connects one PBMS and several process chambers, which greatly improves the commercialization possibility of the PBMS. ACALs was designed based on Stokes number and evaluated by numerical method. Numerical analysis results showed aperture diameter changeable aerodynamic lenses can focus 5 to 100 nm standard particles at 0.1 to 10 torr upstream pressure.

An Analysis of Bed Change Characteristics by Bed Protection Work (바닥보호공 설치에 따른 하상변동 특성 분석)

  • Son, Ah Long;Kim, Byung Hyun;Moon, Bo Ram;Han, Kun Yeun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.35 no.4
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    • pp.821-834
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    • 2015
  • This study presents the analysis of flow and bed change characteristics considering bed protection work built on the immediate downstream of weir to protect river bed from scouring. The study area is 37km reach from Hyunpoong station to Masuwon station including Hapcheon- Changryoung multi-function weir in the Nakdong river. CCHE2D model is calibrated and validated for evaluating the flow and bed change characteristics during Typhoon Kompasu in 2010. Three simulation conditions are set up: Case 1 is a natural channel without installation of weir. Case 2 involves an installation of weir in the natural channel. Case 3 involves an installation of weir with bed protection in the natural channel. Flood frequency (50, 100 and 200yr) is applied to each scenario to analyze the effects of bed protection work. While the sediment rate is increased in the downstream of fixed gate and sluice-type gate, river bed scouring rate is increased in the downstream of lift-type gate in Case 2 comparing with the results of Case 1. The river bed scouring is not occurred in the immediate downstream of weir (~30m) due to the effect of bed protection, but larger amount of sediment is occurred in the downstream of weir (60m~) which the bed protection is not installed comparing with the results Case 1. Through the results of simulation considering bed protection work, this study would be helpful to expect bed change and operate the weir as well as manage.

Analysis of the Secondary Chemistry Materials at 5 Centers for the University Affiliated Science-Gifted Education and Investigation of the Gifted Students' Perception (대학부설 5개 과학영재교육원의 중등화학 교재 분석과 영재학생들의 인식 조사)

  • Lee, Sang Kwon;Mo, Ran
    • Journal of Science Education
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    • v.36 no.1
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    • pp.106-119
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    • 2012
  • In order to promote national competition on knowledge based-society in 21centuries, it is important for us to train talented people who have much creativity. Comparing curriculums and contents studied in SECG (Science Education Center for the Gifted) and other organizations is object of this thesis. Finding implications of proper GATE(gifted and talented education) by understanding the present conditions is also a part of this thesis. We select 5 Science Education Centers for the Gifted and devise framework for analysis in order to analyze chemical textbooks in GATE programs. The framework consists of 6 categories including the contents, the level of activities, the opening extent of experiments, and the ability to think creatively. In our study of textbooks, we have found that the contents of chapters are divided properly but lacked the field of frontier and convergence science. Their activity types will have to develop programs which consist of various activities such as lectures and experiments. Precedent studies and study activities to promote scientific thinking were rated highly in general ratio. The level of studies that we analyzed lacked creative activities very much. In the opening extent of experiments, activities in the level 2 and the level 3 were low-rate. And in our study of thinking creatively, activities of promotion for expanded and related-ability to think seemed to lack. In order to achieve specific education for the gifted children, developments of GATE program is required. In the in-depth analysis from the questionnaires of Likert's method's descriptions, narrations, and interviews, it is divided into two answers in depth: contents of program, management of program. These also divided into two answers by attitude: positive answer or negative answer. According to the responses of the contents of program, the result of analysis shows that most respondents have positive reactions to not only contents and the managing method of SECG programs, but also to individual enhancing-abilities overall.

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Implementation of Efficient Container Number Recognition System at Automatic Transfer Crane in Container Terminal Yard (항만 야드 자동화크레인(ATC)에서 효율적인 컨테이너번호 인식시스템 개발)

  • Hong, Dong-Hee
    • Journal of the Korea Society of Computer and Information
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    • v.15 no.9
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    • pp.57-65
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    • 2010
  • This paper describes the method of efficient container number recognition in colored container image with number plate at ATC(Automatic Transfer Crane) in container terminal yard. At the Sinseondae terminal gate in Busan, the container number recognition system is installed by "intelligent port-logistics system technology development", that is government research and development project. It is the method that it sets up the tunnel structure inside camera on the gate and it recognizes the container number in order to recognize the export container cargo automatically. However, as the automation equipment is introduced to the container terminal and the unmanned of a task is gradually accomplished, the container number recognition system for the confirmation of the object of work is required at ATC in container terminal yard. Therefore, the container number recognition system fitted for it is necessary for ATC in container terminal yard in which there are many intrusive of the character recognition through image including a sunlight, rain, snow, shadow, and etc. unlike the gate. In this paper, hardware components of the camera, illumination, and sensor lamp were altered and software elements of an algorithm were changed. that is, the difference of the brightness of the surrounding environment, and etc. were regulated for recognize a container number. Through this, a shadow problem, and etc. that it is thickly below hung with the sunlight or the cargo equipment were solved and the recognition time was shortened and the recognition rate was raised.

A Study on the Restoration of Stone Railings at Gwanghwamun Woldae in Gyeongbokgung Palace (경복궁 광화문 월대(月臺)의 난간석 복원에 관한 고찰)

  • JEON, Nana
    • Korean Journal of Heritage: History & Science
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    • v.54 no.4
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    • pp.112-131
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    • 2021
  • The Gwanghwamun Gate of the Gyeongbokgung Palace was established in 1866 when Heungseon Daewongun rebuilt the Gyeongbokgung Palace. In Gwanghwamun, a large platform, woldae was established to reveal its hierarchy. The Gwanghwamun Woldae was equipped with stone railings on the left and right sides, fishing routes in the center, and stairs and slopes to the south. The Yongdu Stone was installed on the south side of the slope, which connected to the woldae, to express the path of the king in a formative manner. The Woldae King Road in Gwanghwamun was expanded in 1915 as the Joseon Promotion Conference was held at the Gyeongbokgung Palace and the woldae was destroyed around 1925. Since then, the figure has not been found since the time before the Gwanghwamun Gate. In the Donggureung royal tombs, there are many stones that are not placed in the royal tombs, including voussoir arch stones, Munsojeon Gugi-bi, as well as Nangan-Seokju, Dongja-seok, and Juk-seok, which are elements of the stone railings. These stone railings and Yongdu-seok are seen as stone objects of the Gwanghwamun Woldae, which can be found through the analysis of the style of the times and comparison with modern photographs.

Species Identification and Tree-ring Dating of Wooden Elements in Myeongjeong-gate of Changgyeong-palace, Seoul, Korea (창경궁 명정문 목부재의 수종 및 연륜연대 분석)

  • Lee, Kwang Hee;Jo, Sang Yoon;Kim, Soo Chul
    • Journal of Conservation Science
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    • v.38 no.2
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    • pp.87-95
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    • 2022
  • This aimed to species identification and tree-ring dating of wooden elements used in the Myeongjeong-gate of the Changgyeong-palace, Seoul, Korea. Of the 79 wooden elements evaluated, 78 were confirmed to be hard pines and one belonged to Abies spp.. Cores of the wooden elements were collected using a drill for tree-ring dating, and ring-width plots of individual samples were constructed using the TSAP software. The tree-ring dating results for the outermost ring of 58 hard pine wooden elements revealed the following felling dates: early spring of 1604-late fall of 1615, late fall of 1706-early spring of 1707, and late fall of 1828-late fall of 1834. The obtained felling dates of the 1600s and 1800s were found to be consistent with those in the construction and repair records of the Annals of Joseon Dynasty, Gwanghaegun's Diary and Changgyeonggung Yeonggeondogam Uigwe. However, the obtained felling dates of the 1700s were not consistent with those in the construction and repair records. Therefore, additional confirmation of repairs that were not included in the records was possible using tree-ring dating.

Electrical Characterization of Lateral NiO/Ga2O3 FETs with Heterojunction Gate Structure (이종접합 Gate 구조를 갖는 수평형 NiO/Ga2O3 FET의 전기적 특성 연구)

  • Geon-Hee Lee;Soo-Young Moon;Hyung-Jin Lee;Myeong-Cheol Shin;Ye-Jin Kim;Ga-Yeon Jeon;Jong-Min Oh;Weon-Ho Shin;Min-Kyung Kim;Cheol-Hwan Park;Sang-Mo Koo
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.36 no.4
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    • pp.413-417
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    • 2023
  • Gallium Oxide (Ga2O3) is preferred as a material for next generation power semiconductors. The Ga2O3 should solve the disadvantages of low thermal resistance characteristics and difficulty in forming an inversion layer through p-type ion implantation. However, Ga2O3 is difficult to inject p-type ions, so it is being studied in a heterojunction structure using p-type oxides, such as NiO, SnO, and Cu2O. Research the lateral-type FET structure of NiO/Ga2O3 heterojunction under the Gate contact using the Sentaurus TCAD simulation. At this time, the VG-ID and VD-ID curves were identified by the thickness of the Epi-region (channel) and the doping concentration of NiO of 1×1017 to 1×1019 cm-3. The increase in Epi region thickness has a lower threshold voltage from -4.4 V to -9.3 V at ID = 1×10-8 mA/mm, as current does not flow only when the depletion of the PN junction extends to the Epi/Sub interface. As an increase of NiO doping concentration, increases the depletion area in Ga2O3 region and a high electric field distribution on PN junction, and thus the breakdown voltage increases from 512 V to 636 V at ID =1×10-3 A/mm.

Development of Operation Software for High Repetition rate Satellite Laser Ranging (고반복율 인공위성 레이저추적을 위한 운영 소프트웨어 개발)

  • Sung, Ki-Pyoung;Choi, Eun-Jung;Lim, Hyung-Chul;Jung, Chan-Gyu;Kim, In-Yeong;Choi, Jae-Seung
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.44 no.12
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    • pp.1103-1111
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    • 2016
  • Korea Astronomy and Space Science Institute (KASI) has been operating SLR (Satellite Laser Ranging) system with 2kHz repetition rate for satellite precise orbit and spin determination as well as space geodesy. But the SLR system was improved to be capable of laser ranging with high repetition rate, up to 10kHz by developing new operation software and novel range gate generator, called HSLR-10. The HSLR-10 will contribute to the accurate spin rate determination of geodetic satellites and geodetic research due to its largest repetition rate in the world. In this study, the development methodology and configuration of operation software are addressed, and its validation results are also presented.

A Study on Comparison and Shortening of Evacuation Time Required of University Library by Simulation (시뮬레이션을 통한 대학도서관의 피난 소요시간 비교 관한 연구)

  • An, Jeong-Pill;Kim, Gwang-Hee
    • The Journal of Sustainable Design and Educational Environment Research
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    • v.16 no.2
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    • pp.10-18
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    • 2017
  • The University library is a reality where facilities can be a massive upset by the space of students to study space and book materials. Also, many print materials can cause fires quickly in fires, resulting in massive amounts of human casualties caused by many toxic gases. This study purpose is compares the time spent in the evacuation of the current state through the simulation, which seeks to derive a reasonable library of evacuation design, and improved inside the evacuation. As a result, the most obvious way to reduce the time required to evacuate is to diversify the evacuation routes and to disperse them. However, if the extension of the gate is not feasible, it is possible to reduce the time of escape by increasing the width of the gate and the width of the stair. If the results of this study are applied to new construction or remodeling of the library and prepare for fire evacuation, it will be a much safer library facility.

The Fermented Soy Products Purchase Condition and Direct-deal Need Analysis in Gyeonggi-do (경기지역 주부의 전통 장류 구입 실태와 산지 직거래 경험자의 직거래 형태에 대한 요구 분석)

  • 조금순;이승교;원향례
    • The Korean Journal of Community Living Science
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    • v.15 no.3
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    • pp.71-84
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    • 2004
  • Recently the globalization of agriculture by the WTO has brought crisis to Korean farmers. Value added agricultural products is the one of the strategies to sustain fanning. The idea for the project traditional fermented soy paste production and distribution was developed by the Gyeonggi-do Agricultural Research Institute. It was necessary to know the purchase condition and consumer needs for production distribution of the soy products. This study aims to investigate the consumers' need analysis of direct-deal soy products and the conditions of a purchase. A questionnaire was administered to 590 subjects living in Gyeonggi-do, Korea. The 107 subjects procured soy paste to buy with the reason of ignorance of preparation (39.2%) and the difficulty of storage and care (31.8%). When selecting the product 95.3%, previous experience (41.1 %) and comparison of each product (34.6%) were major answers, wanted direct-deal purchase from producers if implemented. 142 subjects(24%) experienced direct deal with producers. The main direct route was government and public offices( 42.4 %). The reason for direct purchase was confidence of agricultural products(77.5%). Delivery of 4kg of soy paste and 1.8 L of soy sauce in a glass container (43.0%) was favored twice a year. The kind of soy products for consumers' needs was Doenjang(57.8%) and Gochujang(18.3%). The preferred methods direct-dealing of soy products was direct order(59.9%) after validation, delivery gate to gate (44.2%) and by the internet(4.9%). The results of the study shows that the types of production would have the kinds and quantities diversity with confidence, sanitation, and safety. To regain successful, traditional tastes it is necessary to develop reliable and tasteful products for consumers and develop promotional material.

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