• 제목/요약/키워드: Line tracing

검색결과 142건 처리시간 0.024초

보일러 내부 고온가스에 노출된 전열 튜브에서의 열유속 평가 방법 (Estimation method of heat flux at tube bank exposed to high temperature flue gas in large scale coal fired boilers)

  • 정재진;송정일
    • 한국태양에너지학회:학술대회논문집
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    • 한국태양에너지학회 2009년도 추계학술발표대회 논문집
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    • pp.259-264
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    • 2009
  • Most of the fossil power plants firing lower grade coals are challenged with maintaining good combustion conditions while maximizing generation and minimizing emissions. In many cases significant derate, availability losses and increase in unburned carbon levels can be attributed to poor combustion conditions as a result of poorly controlled local fuel and air distribution within the boiler furnace. The poor combustion conditions are directly related to the gas flow deviation in upper furnace and convection tube-bank but a less reported issue related to in large-scale oppose wall fired boilers. In order to develop a on-line combustion monitoring system and suggest an alternative heat flux estimation method at tube bank, which is very useful information for boiler design tool and blower optimizing system, field test was conducted at operating power boiler. During the field test the exhaust gases' temperature and tube metal temperature were monitored by using a spatially distributed sensors grid which located in the boiler's high temperature vestibule region. At these locations. the flue gas flow is still significantly stratified, and air in-leakage is minimal which enables tracing of poor combustion zones to specific burners and over-fire air ports. Test results showed that the flue gas monitoring method is more proper than metal temperature distribution monitoring for real time combustion monitoring because tube metal temp. distribution monitoring method is related to so many variables such as flue gas, internal flow unbalance, spray etc., Heat flux estimation at the tube bank with flue gas temp. and metal temp. data can be alternative method when tube drilling type sensor can't able to use.

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수중 음파 굴절효과를 고려한 전방주시소나 기뢰 위치 추정기법 연구 (A Study on Mine Localization of Forward Looking Sonar Considering the Effect of Underwater Sound Refraction)

  • 설호석;오래근;양원준;윤영글;최지웅;한상규;권범수
    • 한국군사과학기술학회지
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    • 제25권3호
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    • pp.231-238
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    • 2022
  • Mine detection has been mainly studied with images of the forward-looking sonar. Forward-looking sonar assumes the propagation path of the sound wave as a straight path, creating the surrounding images. This might lead to errors in the detection by ignoring the refraction of the sound wave. In this study, we propose a mine localization method that can robustly identify the location of mines in an underwater environment by considering the refraction of sound waves. We propose a method of estimating the elevation angle of arrival of the target echo signal in a single receiver, and estimate the mine location by applying the estimated elevation angle of arrival to ray tracing. As a result of simulation, the method proposed in this paper was more effective in estimating the mine localization than the existing method that assumed the propagation path as a straight line.

정보기기 소스코드 유사성 분석에서 목적물 검증 (Comparison procedure in evaluation analysis of source code comparison on Embedded system)

  • 남상엽;김도현;이규대
    • 한국소프트웨어감정평가학회 논문지
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    • 제17권2호
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    • pp.31-38
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    • 2021
  • 소스코드 감정목적물의 유사성을 판단하는 경우, 양측의 비교대상 소스코드는 컴파일과 실행이 가능 해야 한다. 또한 시스템 소스의 경우에는 하드웨어와의 인터페이스가 일치하는지 확인이 되어야 한다, 그러나 현실적으로 분쟁당사자의 소스코드가 완전하지 않은 상태로 제공되는 경우가 발생하고 있다. 분쟁을 제기하는 측에서는 동작 특성이 자사의 기능과 유사하고, 출력되는 표현과 기능이 유사한 이유로 소스코드의 핵심부분이 유사한 것으로 판단하고, 감정을 요청하고 있다. 분석과정에서 소스코드의 컴파일 오류 발생 시, 감정인은 소스코드의 흐름도를 작성하고, 함수별 코드의 흐름을 추적하는 방법을 적용하게 된다. 그러나 이 방법은 간접적이고, 감정인의 주관적인 판단이 적용되어 유사성 분석결과에 객관성에 대한 다툼이 우려된다. 본 연구에서는 임베디드 시스템에 적용된 소스코드분쟁의 감정사례를 통해 검증되지 않은 소스코드 유사성 도출의 문제점과 개선 방향을 다룬다.

자율주행을 활용한 소프트웨어 교육프로그램 개발 (Development of Software Education Program using Self-driving)

  • 윤효순;정민규;김경백
    • 스마트미디어저널
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    • 제13권2호
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    • pp.145-155
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    • 2024
  • 디지털 전환 시대에서 소프트웨어와 인공지능 교육의 중요성이 강조됨에 따라 다양한 교육자료가 개발되어 보급되고 있다. 소프트웨어 교육의 목적을 달성할 수 있도록 학교 현장에 적합한 다양한 소프트웨어 교육프로그램들이 제공될 필요가 있다. 본 연구에서는 중등학교 소프트웨어 교육에 적용할 수 있는 자율주행을 활용한 소프트웨어 교육프로그램을 개발하여 중등학교 학생들을 대상으로 적용하였다. 개발한 소프트웨어 교육프로그램은 체험과 실습을 중심으로 다양한 센서들을 활용한 물체 탐지, 라인 트레이싱과 같은 다양한 동작 제어 프로그램들로 구성된 피지컬 컴퓨팅 프로그램이다. 개발한 소프트웨어 교육프로그램의 효과성을 측정하기 위한 설문 결과, 학생들의 소프트웨어와 인공지능에 대한 태도와 진로 지향도 그리고 소프트웨어 교육에 대한 만족도가 90% 이상이었고 제안한 교육프로그램에 대한 만족도가 95% 이상이었다.

Openbite을 나타내는 성인의 치열 특성 및 그에 따른 골격적 특성 분석 (An analysis of the dental arch and skeletal characteristics in adult patients exhibiting open bite)

  • 이진우
    • 대한치과교정학회지
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    • 제34권4호
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    • pp.289-301
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    • 2004
  • It is the purpose of this study to characterize oral symptoms and to comprehend the cause and the relapse possibility of patients with open bite. This case study examines the orthodontic treatment of a group of female patients with open bite and Angle's Class I malocclusion. A cephalograph of the patient was taken and tracing of the radiograph was completed. In addition to Bjork and Ricketts analysis, additional measurements of specific areas were taken. The occlusal plane was determined by drawing a line connecting the mesiobuccal cusp tip of the maxillary first molar and the incisal edge of the maxillary central incisors. Patients were divided into two groups depending on the relationship between the marginal ridge of the maxillayy first premolar and the drawn line. Those patients with marginal ridges above the occlusal plane were placed into Group 1, while Group 2 subjects exhibited marginal ridges lower than the occlusal plane. The common characteristics within each group and the characteristic differences between each group both prior to and after orthodontic treatment were examined, and finally, the functional oral volume of each patient was analyzed. The results of the case study were as follows: 1. An examination of the skeletal relationship and anatomical form for both Group 1 and 2 showed that all subjects exhibited hyperdivergent skeletal forms, but Group 2 subjects generally demonstrated underdevelopment of the mandible and a smaller articular angle, resulting in an anterior positioning tendency of the mandible. 2. An analysis of the maxillary arches of Group 1 subjects prior to and after orthodontic treatment showed that the antero-inferior direction had changed to an antero-superior directional tendency, while the maxillary arches of the Group 2 patients showed a trend from an antero-superior direction to an antero-inferior relationship. The mandibular arches in both groups showed a change to an antero-superior direction. 3. Functional space analysis showed that Group 2 patients exhibited a greater tendency of haying palatal planes that drop in a postero-inferior direction, resulting in a more severe open bite than their Group 1 counterparts. The results of this case study show that although patients belonging to either Group 1 or 2 exhibited few external differences in the appearance of open bite, an examination of the dental and skeletal relationships by analyzing patient cephalographs showed that patients presenting with flat maxillary occlusal planes exhibited more severe open bite relationships than patients with curved occlusal planes.

전주 죽림지역 온천수의 화학적 및 동위원소적 특성 (Hydrochemical and Isotopic Properties of the Thermal Spring Water from Chonju Jukrim District, Korea)

  • 나춘기;이무성;이인성;박희열;김옥배
    • 자원환경지질
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    • 제30권1호
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    • pp.25-33
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    • 1997
  • The purpose of this study is to examine the feasibility of using stable isotopes as a hydrologic tracer, and to elucidate the groundwater circulation system and the source of S component dissolved in thermal water of the Chonju Jukrim thermal spring district based on the O, H and S isotopic variabilities of environmental materials including bedrock, rainwater, surface water, shallow subsurface water and thermal spring water. The ${\delta}^{18}O$ and ${\delta}D$ of subsurface waters and surface water show highly restricted range and plotted on the same meteoric water line as a ${\delta}D=8{\delta}^{18}O+19$ line, and derivate from the mean annual isotopic composition of the rain water but are analogous to those of rain waters precipitated during winter season, indicating that ground waters are originated from the meteoric water and are strongly affected by the seasonal variation of air mass. Thermal spring waters are more depleted in ${\delta}^{18}O$ and ${\delta}D$ than those of shallow ground water and surface water. It can be explained by the difference of recharge area. The hydrochemical properties of subsurface waters and surface water devide into two groups: $Ca(HCO_3)_2$ type including shallow subsurface water and surface water, and $Na(HCO_3)$ type of thermal spring waters. The ${\delta}^{34}S$ values of thermal spring water show very high positive and quitely distinct from those of shallow subsurface water and surface water that are similar to those of bed rocks, indicating that sulfate dissolved in thermal spring water has not only a terrigenic origin, but also originates partially from the foreign source containing very heavy ${\delta}^{34}S$ component such as an ancient sea water. However, the presence of $H_2S$ can not be ignore the affact of the isotopic fractionation to explaine the heavy ${\delta}^{34}S$ of thermal spring water. Overall, the Oxygen and Hydrogen stable isotopes can identify the source and the circulation system of the natural waters and the S-isotopes can provide a crucial clue on tracing the dissolved material transports in the circulation system of the natural water.

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중앙아시아의 신에 관한 연구 -타지크(Tadzhik)를 중심으로- (A Study on the Foot Wear -On the Tadzhik of central Asia-)

  • 정하신
    • 대한가정학회지
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    • 제28권1호
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    • pp.21-41
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    • 1990
  • All the cultures are enriched and developed themselves through the contact with another culture, which propagate and transplant its new cultural elements to a time-honoured tradition. Therefore, the investigation of the origin of each culture means to find out the all the elements of each culture itself in the end. In Korean Costume, we can find both the Costume of frizid jone and that of temperate jone togther, effected by the influence of typical continental climate. Accordingly, we can also realize that both Lee, of southern tribe and Haw, of northern tribe suitable for the protection of cold weather, existed in Korea. Even Lee and Hwa were used together, Hwa had been appeared earlier than Lee along with the Skitai Costume and we can find its origin in the line of Skitai costume. In Central Asia, Tadjhik was the only race tracing their ancestry from ancient Iranic genuinely and they had been keeping the culture of Skitai origin continuously. The purpose of this thesis is to examine Korean's own culture of the footwear through the investigation of Tadjhik's culture of costume, specially through the culture of Tadjhik footware. To reach the conclusion of this thesis, the comparision and investigation between Korea and Tadjhik was made carefully for the followings, culture of life and costume, forms and materials of footwear. 1. The treasers and boots made by leather and felt was the origin of costume culture of Central Asia and aboves were appeared in persian costumn for the first time. We can consider that those had connection with Korean culture of costume. 2. Form of Tadjhik footwear can be devided by hwa and Lee, and there was a big difference in form between that of mountain area and plain area. We can find more rariety in footwear of mountain area. 3. If we compare the form of Hwa and Lee of Tadjhik with our own footwear, we can find out many things in common and there are lots of similarities particularly in form and material. 4. We can say that the difference of Tadjhik and Korean was the preference of Hwa for Tadjhik and Lee for Korean, aboves came from the different totography, climate condition and life style. 5. The form of male and female footwear of tadjhik was almost similar, but female footwear had various and beautiful decorations for the ornament. 6. The materials of Tadjhik footwear was mostly leather, and Hwa was used particularly for labour purposes. 7. We can expect that Tadjhik of Central Asia and Korea had a similar orgin and style on the footwear. It can be expected that we can find out many common things in further investigation of the study of Tadjhik costume and will exert the examination continuously.

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편측성 순구개열자의 안면비대칭에 관한 연구 (FACIAL ASYMMETRY OF UNILATERAL CLEFT LIP AND PALATE PATIENTS)

  • 손우성;김미경
    • 대한치과교정학회지
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    • 제25권1호
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    • pp.13-18
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    • 1995
  • 편측성 순구개열자의 교합과 안모의 비대칭이 연령 증가에 따라 변화하는 양상을 파악하여 비성형술의 시행시기 결정, 교정치료 도중의 안모 변화 예측 등에 이용하고자 구순과 구개의 수술을 시행받은 편측성 순구개열자 39명을 8세 이하, 9세에서 12세, 13세 이상의 3군으로 나누어 정모두부방사선 규격사진을 채득하여 투사도를 작성하였다. 좌, 우측 전두협골봉합의 내면을 잇는 선을 수평 기준선(HR)으로 하고, HR을 수직 이등분하는 선을 정중시상 기준선(MSR)으로 정하여 상악골, 상하악 치열, 하악골의 좌우 비대칭을 판단하기 위한 17 항목을 선정, 계측하였다. 안모 비대칭의 정도를 파악하기 위하여 student t-test를, 성장에 따른 비대칭의 변화를 알아 보기 위하여 one-way ANOVA를 시행하여 다음과 같은 결과를 얻었다. 1. 편측성 순구개열자에서 비대칭은 다양하게(1.22-3.47$mm/^{\circ}$) 나타났다. 특히 정중선에 대한 상악 제1대구치와 중절치까지의 거리, 하악지의 길이에서 비대칭이 크게 나타났다. 2. 편측성 순구개열자에서 비대칭은 몇 항목에서 뚜렷한 특징을 보였다. 비중격은 모두 파열측으로 변위되었고 비강의 하연은 대부분이 파열측에서 더 하방에 위치하였다. ANS는 주로 비파열측으로, 상악 중절치는 주로 파열측으로 변위되었다. 3. 성장에 따른 비대칭의 변화양상이 가장 뚜렷한 항목은 비중격으로 9세에서 14세까지도 비대칭의 양이 증가하였다.

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홉킨스의 인종 다시쓰기-"숨겨진 자아,"과거/기억, 근친상간, 그리고 흑인여성의 몸 (Rewriting Race in Hopkins's Of One Blood; Or, the Hidden Self: "the Hidden Self," Past/Memory, Incest, and Black Female Body)

  • 강희
    • 영어영문학
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    • 제54권2호
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    • pp.301-322
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    • 2008
  • Pauline Hopkins's Of One Blood; Or, the Hidden Self was published in the Colored American Magazine during 1902-03. As a literary experimentalist and a political protester, Hopkins uses her fiction as a medium to overcome and ameliorate the violently racialized surroundings of the turn-of-the-century America. Having been faced with racist rhetorics and theories growing on biological differences between races, Hopkins must have felt an overwhelming urgency to challenge the heritage of slavery in American history. In order to speak out her political agenda in such a milieu, she needed a new setting as well as new narrative materials for the new era. She had to move the setting from America to Africa, the ancient utopian Ethiopia; her interest in the ancient African civilization reflects both a popular African-American vision of Africa and the movement of "black nationalism" of the time. She also needed materials from nineteenthcentury sciences, the newly evolving theories of psychology and mysticism (spiritualism/mesmerism), to explore the meaning of "the hidden self" which unfolds the complex nature of Hopkin's position on race, "blood," and African-American racial subjectivity. Hopkins in the novel explores not the color line but the bloodline. Tracing the horrific legacy of incest in the history of slavery, she attempts to redefine the true racial identity of African-Americans in America and to reconstruct their past, both family and race history. At the very center of her major tropes in the novel-such as "of one blood," "the hidden self," and incest-exists female body. Black female body, though it represents the violent site of sexual body (rape and incest) in slavery, ultimately becomes a vehicle to convey and preserve the truth of racial memory/past/history for African-Americans. As a conveyor of the past, black women not just connect the past and the present but also reawaken AfricanAmericans with the legacy of the African 'pure' bloodline. Hopkins's vision here necessitates the reevaluation of black women's role in family and history, heralding the 20th-century black feminine writing. With the major tropes, Hopkins clearly suggests that the blood of (African-)Americans is unrecognizably intermixed. Although the novel ends with ambivalence and without resolution on what Africa signifies, those tropes certainly offer her a vehicle for criticizing as well as for challenging the racial reality of America.

21세기 한국 소설의 라틴아메리카 소설 경향 - 황석영, 임철우, 김연수, 박형서 소설을 중심으로 (A tendency of Korean contemporary fictions according to Latin American fictions - Focus on the novels of Seok-yeong HWANG, Cheol-woo IM, Yeon-soo KIM, Hyeong-seo PARK)

  • 함정임
    • 비교문화연구
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    • 제25권
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    • pp.313-336
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    • 2011
  • The objective of this thesis is to unfold Latin American trends overlapping with Korean contemporary novels as an interesting scene in the circle of Korea literature at the beginning of the 21st century. This study was conducted largely in two directions. One is examining how long novel A Guest of Seok-yeong HWANG, a representative realist writer in Korea, and another long novel One Hundred Years Motel (Baeknyeon Motel) of Cheol-woo IM, a writer who has expressed Korean shamanic flowering as his fictitious characteristic since the 1980s, meet and interact with the world of magic realism in long novel One Hundred Years of Solitude of G. G. Marquez born in Colombia, Latin America, and the other is discussing the fictional techniques of H. L. Borges overlapping with short stories in novel collections The Age of Twenty and Fictions of Midnight by, respectively, young writers Yeon-soo KIM and PARK Hyeong-seo who displayed a unique world of fictions in the 2000s. For these purposes, we developed the points of discussion from the viewpoint of 'the meeting of two essences' for Seok-yeong HWANG and Marquez, of 'the meeting of two 'hundred years'' for Cheol-woo IM and Marquez, of 'novel writing as the finding of the original' for Yeon-soo KIM and Borges, and of 'novel writing surrounding fictions' for Hyeong-seo PARK and Borges. Around 2000, the trend of Latin American novels emerged as a phenomenon in Korean novels. It was probably a natural consequence of contemporary writers' struggling with genres and post-genres, the overturn of the center and the periphery, and blurred boundaries. Seok-yeong HWANG, Cheol-woo IM, Yeon-soo KIM, and PARK Hyeong-seo borrowed the contents and techniques of Latin American novels, but further research is required on how continuously their works internalized the characteristic properties of Marquez-style, Borges-style or polyphonic Latin American novels and, by doing so, how much they expanded or determined their own line. This is why this study has been performed productively out of vital importance. In every age throughout history, there have been the phenomena of encountering and sympathizing, and overlapping and spreading with foreign novels. This study is meaningful in that it illuminated the aspects of Korean contemporary novels in the flow of world literature through tracing the origin and reality of the trend of Latin American novels emerging conspicuously through overlapping particularly with Korean novels published in the 2000s.