• Title/Summary/Keyword: 칼만 와

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A Study on the Flame Structure and Stabilization in a Divergent Flow (확대관 흐름에 있어서 화염의 안정성 및 구조에 관한 연구)

  • 최병륜;이중성
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.18 no.2
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    • pp.512-518
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    • 1994
  • An experimental study is made on turbulent diffusion flames stabilized by a circular cylinder in a divergence flow. In this paper, stabilization characteristics and flame structure are examined by varying the divergence angle of duct and position of a circular cylinder. The fuel used is a commercial grade gaseous propane injected by two slit of rod. It is found that the positive pressure gradient greatly influences the eddy structure behind the rod. and that two different kinds of combustion patterns exist at the blowoff limit depending on the divergent angle of duct. They are distinguished by their wake structures: one associated with Karman vortex shedding, the other without it. Also, the blowoff velocity in the former is found to be higher than in the later.

The Effect on Wake Flow and Vortex Shedding Frequency by Vortex Stabilizer in Karman Vortex Type Air Flow Sensor (칼만와류식 공기유량센서의 와안정판이 후류유동장과 와유출주파수에 미치는 영향)

  • 임성원;류병남;이종춘;부정숙
    • Journal of Advanced Marine Engineering and Technology
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    • v.25 no.4
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    • pp.846-856
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    • 2001
  • An experimental study has been made to investigate the effect on wake flow and vortex shedding frequency by vortex stabilizer in Karman vortex type air flow sensor. The conditions investigated include 3 types of shapes and 3 types of separation distances of the vortex stabilizer. The phase averaged technique and smoke-wire flow visualization method are used to understand the detail information. The rolling up position of shear layer is fixed by the influence of the vortex stabilizer. Especially, the convex type vortex stabilizer has shown the more stable repeatability and linearity regarding the vortex shedding frequency compared to the other types.

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Direct Bonding of SiN/SiO Silicon wafer pairs (직접접합 질화규소/산화규소절연막 이종실리콘기판쌍의 제조)

  • 이상현;서태윤;송오성
    • Proceedings of the KAIS Fall Conference
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    • 2001.11a
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    • pp.169-172
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    • 2001
  • 다층 MEMS구조의 기초기판쌍 소재로 쓰일 수 있는 Si∥SiO₂/Si₃N₄∥Si 기판쌍의 직접접합 가능성을 확인하기 위해서 2000Å-SiO₂와 500Å-Si₃N₄층을 가진 직경 10cm의 실리콘 기판을 각각 친수성 및 소수성 표면세척을 하고 청정분위기에서 경면끼리 가접을 실시하였다. 가접된 기판쌍을 통상의 박스형 전기로를 이용하여 400, 600, 800, 1000, 1200℃ 범위에서 2시간 동안 가열하여 접합을 완료하였다. 완성된 기판쌍을 적외선분석기를 이용하여 접합면적을 확인하였고, 면도칼 삽입법으로 접합계면에너지를 측정하였다. 실험온도 범위 내에서 Si∥SiO₂/Si₃N₄∥Si 기판쌍은 1000℃ 이상에서 접합계면에너지는 2,344mJ/㎡을 나타냈으며, 이는 기존의 Si/Si의 동종접합기판쌍과 동등한 수준의 접합강도로서 부가가치가 큰 새로운 조합의 기판쌍 제조가 가능하였다.

Verification of the Suitability of the ATP Luminometer as the Monitoring Tool for Surface Hygiene in Foodservices (급식소 식품접촉표면 위생 모니터링 도구로서의 ATP Luminometer 적합성 확인)

  • Kim, Yang-Sook;Moon, Hey-Kyung;Kang, Seong-Il;Nam, Eun-Jeong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.39 no.11
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    • pp.1719-1723
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    • 2010
  • The purpose of this study was to verify feasibility of using a ATP Luminometer, real-time hygiene monitoring tool for food contact surfaces in foodservices. For this, 54 cutting boards, 70 knives, 21 rubber gloves in 4 institutional foodservices were studied. ATP (RLU: relatively light unit) values by ATP Luminometer were compared with APC (CFU: colony forming unit) of swabbing culture method using aerobic count plates of 3M petrifilm. ATP ranged from 0 RLU/$cm^2$ to 64693 RLU/$cm^2$ on knives, from 0.1 RLU/$cm^2$ to 6743.6 RLU/$cm^2$ on cutting boards and from 31 RLU/$cm^2$ to 465635 RLU/$cm^2$ on the rubber gloves. APC ranged from 0 CFU/$cm^2$ to 166667 CFU/$cm^2$ on knives, from 0 CFU/$cm^2$ to 1000 CFU/$cm^2$ on cutting boards and from 0 CFU/$cm^2$ to 730000 CFU/$cm^2$ on the rubber gloves. To express the degree of association between ATP and APC, a linear regression was performed. There were significant positive correlations found between log RLU and log CFU on the knives (r=0.84, p<0.001), the cutting boards (r=0.79, p<0.001), the rubber gloves (r=0.78, p<0.001). Results of this study showed the possibility that ATP bioluminescence technique can be used as the monitoring tool for surface hygiene in foodservices.

A Survey on the Holding Amount of Cooking Tools of the Farm and Fishing Villages in Chungnam Area (충남지역 농어촌의 조리기구 보유실태에 관한 조사)

  • 김영인;김기숙
    • Korean journal of food and cookery science
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    • v.9 no.1
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    • pp.7-13
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    • 1993
  • This survey was performed to investigate the holding amount of the various kinds of cooking tools of the farm and fishing villages in Chungnam area. The results were as follows: 1. The holding ratio of refrigerators was the highest (97.9%), and that of toasters was the lowest (1.9%) among the electric tools. 2. The holding ratio of gas-ranges was the highest (95.7%) and that of gas oven-ranges was the lowest (1.2%) among 4 kinds of gas tools under investigation. 3. The holding amount of pans was the highest among the cooking tools and that of wicker baskets was very high among the small cooking tools. The holding ratios of egg-cutters and lemon-squeezers were very low (4.1% and 2.9%, respectively). 4. The holding ratios of various kinds of cooking tools were related to the housewife's educational background and family income.

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The Structural Analysis and Criticism of Geommu (Korean Sword Dance) - Focusing in Literary Works and Music - (검무 구조 분석 시론 - 문헌과 음악을 중심으로 -)

  • Kim, Young-Hee
    • (The) Research of the performance art and culture
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    • no.34
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    • pp.9-42
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    • 2017
  • Of all Geommu(劍舞, Korean sword dance), Gisaeng-Geommu danced by gisaeng(妓生, Korean female entertainers) for private guests and at the royal court. The Sword dance in the late Joseon Dynasty used to be dynamic exuding menacing "sword spirit(劍氣)." Sword dance being transmitted today is more ritualistic and elegant. This study considers Korean sword dance has a core structure and motifs transcending generational differences, and based on this critical thinking, aims to analyze the structure of Korean sword dance. This study analyzed the prose "Geommugi(劍舞記)" by Park Je-ga(朴齊家) and the poem "Mugeompyeonjeongmiin(舞劍篇贈美人)" by Jeong Yak-yong(丁若鏞) out of literary works from the late Joseon Dynasty, and from official records of rituals(笏記), "Geomgimu(Sword Dance, 劍器舞)" and "Geommu" in "Gyobanggayo(敎坊歌謠)." In the introduction part of Sword dance, a dancer appears, bows and performs a hand dance or hansam(汗衫) dance to and fro. In the development part, a dancer meets with a sword but first hesitates to hold it and dances holding swords in both hands. The climax shows expert sword skills and combat scenes. In the conclusion part, the court dance involves a dancer bidding a formal farewell, while the dance for entertainment, a dance throws away the sword to finish. From literature materials, the structure of Korean sword dance could be divided into an introduction, a development, a climax and a conclusion. Based on this, this study analyzed sword dance movements by linking the beats accompanying the current sword dance, in the order of a Yeombul, the traditional Korean ballad Taryeong or Neujeun Taryeong, Jajin Taryeong, Taryeong and Jajin Taryeong. The introduction part includes a Buddhist prayer and the beginning of Taryeong. Dancers appear, and in two rows they dance facing each other. On the slow beat, their dances are relaxed and elegant. The development part is matched with Jajin Taryeong. Dancers sit in front of swords and grab them, and they dance holding a pair of swords. The beat gradually becomes faster, progressing the development of the dance. But then, the slower Taryeong is placed again. The reason behind it is to create a tension for a little while, before effectively reaching a climax by speeding up the tempo again. Moving on to Jajin Taryeong, dancers' movements are bigger and more dynamic. The highly elated Jajin Taryeong shows dance movements at the climax on fast, robust beats. In the conclusion part, the beat is quick-tempo and on the upbeat again on Jajin Taryeong. Driving on without a stop on the exciting Yeonpungdae(燕風臺) melody, dancers standing in a line dance wielding the swords and bow before finishing.

A Comparative Study on the Theory of Tectonics between Gottfried Semper and Karl B$\ddot{o}$tticher (고트프리트 젬퍼(Gottfried Semper)와 칼 뵈티허 (Karl B$\ddot{o}$tticher)의 텍토닉 개념 비교)

  • Jung, In-Ha
    • Journal of architectural history
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    • v.7 no.4 s.17
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    • pp.77-91
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    • 1998
  • The theory of tectonic appeared in the midst of 19th century as German architects adopted new materials and structural technology, invented by creative engineers, into architectural design. This does not merely mean a technical problem but concern the redefinition of architecture in term of an aesthetic, cultural, and ontological identity. Furthermore it alluded to a desire on the part of architectural theorists to actualize artistic and spiritual goals out of new constructional necessities. Because of their complex discourse that assumed the possibility of communication between philosophical and technical aspects, between ideal and real concerns, tectonics becomes until now the most important issue in architecture. The concept of tectonic was intensively investigated by Gottfried Semper's and Karl B$\ddot{o}$tticher architectural writings. They contributed to clarify the principle aspects of tectonic within architectural, philosophical, and anthropological discourses of 19th century. Gottfried Semper stressed an understanding of how architecture took on physical form in earliest human culture. He placed great importance on the artistic expression of materials. But unlike Semper who argued the cladding of the structural frame by decorative wall system, Karl Botticher required maximum visibility of structural frame. This represents the different positions between Gottfried Semper and Karl Botticher

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Sap Transmission Pattern of CGMMV and Effect of Disinfectant on Watermelon (수박 CGMMV의 즙액전염 양상과 전염 억제제의 효과)

  • Ko, Sug-Ju;Lee, Yong-Hwan;Cha, Kwang-Hong;Lee, Tae-Seon;Park, In-Jin
    • Research in Plant Disease
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    • v.10 no.2
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    • pp.150-153
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    • 2004
  • This study was conducted to investigate the sap transmission pattern of CGMMV and to select the disinfectant of sap transmission on watermelon cultivation. Being investigated CGMMV occurrence change after transplanting two diseased plants among 47 plants on the watermelon house, disease spread rapidly from early growth stage of 4 % to late growth stage of 83 %. When the grafting knife and topping scissor was dipped onto the several disinfectants before grafting or topping, disease suppressed 87-95 % on whole milk, skim milk, tri-sodium phosphate, and sodium hypo-chloride solution. Disinfection effects of 88.2 % and 91.2 % on whole milk and skim milk were showed when the hand dipped on the disinfectants.

Jurisprudence in the History of Statistics (통계학사 속에서의 법)

  • Jo, Jae-Keun
    • Communications for Statistical Applications and Methods
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    • v.18 no.5
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    • pp.559-570
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    • 2011
  • The role of jurisprudence is examined in the early history of probability and statistics. From the mid-17th to the early 18th century, Christiaan Huygens and Jacob Bernoulli used mathematical expectation to solve the problems that originated from games of chance. We demonstrate that their concept of expectation as a fair price for participating in a game came from the legal concept of 'fair trade'. In addition, we consider that the probability that Bernoulli defined in his Ars Conjectandi originated from the legal concept of 'degree of certainty'. After considering some contributions of Laplace and Poisson, we examined the history of census and statistical survey in the early 19th century. Contrary to the history of the 17th and 18th century, statistics influenced society and law in the 19th century.

A Filter Design for Reducing Altitude Measurement Errors Arising during Aircraft Landing (항공기 착륙 시에 발생하는 고도측정 오차 개선을 위한 필터설계)

  • Song, Dae-Bum;Lim, Sang-Seok
    • Journal of Advanced Navigation Technology
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    • v.3 no.2
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    • pp.97-107
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    • 1999
  • Passive sensors such as Laser Range Finder(LRF) and Forward Looking Infrared(FLIR) camera frequently used for tracking aircraft landing produce the measurements of elevation angle contaminated by large noise due to the exhaust plume disturbance. This results in poor tracking performance if the extended Kalman filter is used for estimation of the range and elevation which are corrupted by the non-Gaussian noise such as plume disturbance. In this paper, an adaptive estimation filter and the extended Kalman filter is combined to produce a combination-type filter. In this approach the adaptive filter is used for the plume-type disturbance noise and the extended Kalman filter is utilized for the measurement of Gaussian type. The proposed combination filter is effective for the trajectory estimation of landing aircraft under the influence of unknown bias and numerical simulations illustrate the performance of the proposed filter.

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