• 제목/요약/키워드: Cross-term

검색결과 757건 처리시간 0.034초

일반 비직교 표면좌표계에서의 비압축성 점성유동의 수치해석 (Calculations of Incompressible Flows In General Nonorthogonal Body Fitted Coordinates: Comparison of Hybrid and QUICK Sehemes)

  • 강동진;배상수
    • 대한기계학회논문집B
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    • 제20권5호
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    • pp.1613-1623
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    • 1996
  • In this paper, two discretization methods, hybrid and QUICK, are tested for the Navier-Stokes equations written in general nonorthogonal body fitted coordinates. Comparison is made by calculating two laminar flows at low Reynolds numbers of 10 - 100. One is a two-dimensional channel of gradually expanding cross section and the other is an axisymmetric flow through a circular tube having a circular constriction. Results show that the QUICK scheme results in a numerical solution more accurate than that of hybrid. The QUICK scheme also shows faster convergence for both test cases. As the number of grid points increases, all numerical solutions converge with more oscillation. The number of grid points in the y-direction(cross stream direction) is also shown to play a significant role in the approximation of convection term within separated flow zone.

영아기 기질 및 부모의 양육행동에 따른 2-4세 아동의 행동억제에 관한 단기종단연구 -8개국 비교문화연구를 위한 기초 연구- (A Short-term Longitudinal Study on Infant Temperament, Parenting Behavior and 2-4 Year Behavioral Inhibition: A Korean sample for 8 cross-cultural studies)

  • 정옥분;;박성연;윤종희;도현심
    • 가정과삶의질연구
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    • 제21권3호
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    • pp.29-38
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    • 2003
  • A three-year longitudinal design was employed to ascertain whether different types of behavioral inhibition(i.e. traditional, peer-social) were stable from toddler to preschool age(2-4 year), and whether inhibited temperament and/or parenting style would independently and interactively predict children's subsequent social and behavioral outcomes. At time 1, 113 toddlers (55 males, 58 females) and their mothers were observed in the traditional inhibition paradigm. At time 2, 36 4-year-old children were observed with unfamiliar peers in the nontraditional inhibition paradigm. Maternal ratings of psychological functioning of children and maternal behaviors were also obtained for both time 1 and 2. Results showed that behavioral inhibition was not stable from toddler to preschool age. Maternal authoritative behaviors at age 2 were negatively associated with preschooler's social reticence. Toddler's behavioral inhibition was negatively associated with maternal authoritative behaviors at age 4. In a cross-lag correlation analysis, maternal authoritative behaviors appeared to affect child's behavioral inhibition more strongly than the other way around.

포토제니 혹은 사진 이미지의 이중성과 정신성 - 에드가 모랭의 논의를 중심으로 (Photogenie as the duality and mentality of the photographic image: a study based on the theory of Edgar Morin)

  • 김호영
    • 비교문화연구
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    • 제34권
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    • pp.71-92
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    • 2014
  • This article presents a study on the concept of "Photogenie", which refers to the duality and mentality of the photographic image, with the viewpoint regarding the photographic image by Edgar Morin. First, we will look at the evolution of the concept of "Photogenie". From the field of photography, the term "Photogenie" means objects that produce light, enough to impress the photographic plate. But theorists of cinema at the beginning of the 20th century have changed the meaning of the term. For Louis Delluc, the "Photogenie" means the effect of union between the reproduction of real and artistic genius. For Jean Epstein, the "Photogenie" means mental quality, nonmaterial or inderterminable, of the photographic and cinematographic image. But Morin synthesized the arguements of Delluc and Epstein. For him, the "Photogenie" indicates both a double character of the photographic image and its mental quality. Then, based on this concept of "Photogenie," Morin said on particular aspects in the photographic image. Considering photography as a double in the anthropological sense, it puts emphasis not only the dual nature of the photographic image but also mental and spiritual quality. Combining the theory of the mage Henri Bergson and Jean-Paul Sartre, he builds his own theory of the mage that concerns both photography and cinema. In short, to Morin, the photographic image is a place where coexist absence and presence, the real and the imaginary, perception and memory, the material and mental, as well that a place of mentality which appear all our memories, hallucinations, dreams, imagination etc.

한(韓)·중(中) 친족 호칭 '형수'와 '제수'에 대한 통시적(通時的) 비교 (A Diachronic Comparison of korean and chinese kinship terms : about 'elder brother's wife' and 'younger brother's wife')

  • 유현아
    • 비교문화연구
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    • 제23권
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    • pp.419-437
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    • 2011
  • In China, elder brother's wife is called 'Sao' or 'Saozi' and younger brother's wife is called 'Fu' or 'Difu', etc. On the other hand, In Korea is called 'Hyeongsu' and 'Jesu'. This paper aims to find that Korean and Chinese kinship terminology 'Hyeongsu' and 'Jesu's origin and characteristics. And considerd reason that Korean kinship terms different changed with Chineses and investigated whether the presence of native language. In China, Kinship term reflected strict species act. Therefore, for elder brother's wife to give dignity 'Sao' in the title that made separately. In other hand, sister-in-law used 'Fu that means submission. The first was to use the same type of Kinship terms in the Korean and Chinese. Because Korea accept of the China's relative terms. But gradually confusion about the meaning of the original issued 'Sao' and wrong term 'Jesu' appeared. In response, 'Hyeongsu' as a two-syllable terms was shown whence they came. Also through literature shows that '아??마', '아??마니 is called native tongue.

Circadian Biorhythmicity in Normal Pressure Hydrocephalus - A Case Series Report

  • Herbowski, Leszek
    • Journal of Korean Neurosurgical Society
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    • 제65권1호
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    • pp.151-160
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    • 2022
  • Continuous monitoring of intracranial pressure is a well established medical procedure. Still, little is known about long-term behavior of intracranial pressure in normal pressure hydrocephalus. The present study is designed to evaluate periodicity of intracranial pressure over long-time scales using intraventricular pressure monitoring in patients with normal pressure hydrocephalus. In addition, the circadian and diurnal patterns of blood pressure and body temperature in those patients are studied. Four patients, selected with "probable" normal pressure hydrocephalus, were monitored for several dozen hours. Intracranial pressure, blood pressure, and body temperature were recorded hourly. Autocorrelation functions were calculated and cross-correlation analysis were carried out to study all the time-series data. Autocorrelation results show that intracranial pressure, blood pressure, and body temperature values follow bimodal (positive and negative) curves over a day. The cross-correlation functions demonstrate causal relationships between intracranial pressure, blood pressure, and body temperature. The results show that long-term fluctuations in intracranial pressure exhibit cyclical patterns with periods of about 24 hours. Continuous intracranial pressure recording in "probable" normal pressure hydrocephalus patients reveals circadian fluctuations not related to the day and night cycle. These fluctuations are causally related to changes in blood pressure and body temperature. The present study reveals the complete loss of the diurnal blood pressure and body temperature rhythmicities in patients with "probable" normal pressure hydrocephalus.

교차류형 100W급 용융탄산염 연료전지 스택 장기운전평가 (Evaluation of Long Term Operation of Cross-flow Molten Carbonate Fuel Cell Stack)

  • 임희천;설진호;류철성;이창우;홍성안
    • 한국수소및신에너지학회논문집
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    • 제6권2호
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    • pp.53-63
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    • 1995
  • 차세대의 새로운 발전방식인 용융탄산염형 연료전지 시스템개발 사업중 실용 스택개발을 위하여 전극유효연적이 $100cm^2$ 인 단위전지를 10단 적층한 Cross Flow형 MCFC스택을 제작하고 2성능측정설비를 구성하여 장기운전시험을 실시하였다 연료로는 $H_2/CO_2/H_2O$의 비율을 72%/18%/10% 로 조성한 가스를 이용하고 산화제가스로는 $O_2/CO_2$$Air/CO_2$ 비율이 33%/67%, 70%/30%가 되는 가스를 이용하여 운전할때의 초기성능 및 15A($150mA/cm^2$) 정부하 상태에서의 장기운전시험시의 전압 강하율을 조사하였다. 운전시간 310시간이 경과된 후의 스택전압은 8.39V이었고 이때의 출력은 125.8W를 보여주었다. 한편 1845시간이 경과한후 공기를 산화제로 이용하는 경우 전압은 6.95V로서 출력 104W를 나타내고 있다. 초기성능치에 의한 에너지 변환효율은 이용율이 40%인 경우 29.65%이었고 80%로 증가하는 경우 약 51.5%가 된다. 1840시간의 경과한때 까지의 전압 강하율은 약 52.4mV/1000hr로서 이전의 스택보다는 전압강하율이 감소되고 있으며 스택의 성능 저하의 주요한 요인은 개회로 전압의 저하로 내부단락동에서 기인하는 것으로 여겨진다. 또한 장기운전사 스택내부에서의 단위전지 전압분포가 균일하지 않음을 알 수 있어 이에 대한 개선을 필요로 한다.

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직접 역필터 설계법을 이용한 스테레오 재생시스템의 Cross-talk 제거 (A DIRECT INVERSE-BASED CROSS-TALK CANCELLATION METHOD FOR STEREO AUDIO SYSTEMS)

  • Kim, Sang-Myeong;Dogeun Han;Semyung Wang
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2002년도 춘계학술대회논문집
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    • pp.559-564
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    • 2002
  • Cross-talk cancellation, inverse filter design or deconvolution in a generic term, is a vital process for a virtual sound realization in the stereo sound reproduction system. Most, if not all, of the design algorithms available for the inverse filter are based on a linearized model of the real physical plant. The result of such a plant-based design method, which may be referred to here as the indirect method, is biased due to both modelling and inversion errors. This paper presents a novel direct cross-talk cancellation method that may be free from the inversion error. The direct method can directly models the inverse filter by a suitable rearrangement of the input and output ports of the original plant so that no inversion is required here. Advantages are discussed with various experiments in an anechoic chamber using a PC soundcard. Binaural reproduction tests conducted showed that the conventional indirect method yields about 8 % reproduction performance error on both ear positions, whereas the direct method offers about 3 %.

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Flexure of cross-ply laminated plates using equivalent single layer trigonometric shear deformation theory

  • Sayyad, Atteshamuddin S.;Ghugal, Yuwaraj M.
    • Structural Engineering and Mechanics
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    • 제51권5호
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    • pp.867-891
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    • 2014
  • An equivalent single layer trigonometric shear deformation theory taking into account transverse shear deformation effect as well as transverse normal strain effect is presented for static flexure of cross-ply laminated composite and sandwich plates. The inplane displacement field uses sinusoidal function in terms of thickness coordinate to include the transverse shear deformation effect. The cosine function in thickness coordinate is used in transverse displacement to include the effect of transverse normal strain. The kinematics of the present theory is much richer than those of the other higher order shear deformation theories, because if the trigonometric term (involving thickness coordinate z) is expanded in power series, the kinematics of higher order theories (which are usually obtained by power series in thickness coordinate z) are implicitly taken into account to good deal of extent. Governing equations and boundary conditions of the theory are obtained using the principle of virtual work. The closed-form solutions of simply supported cross-ply laminated composite and sandwich plates have been obtained. The results of present theory are compared with those of the classical plate theory (CPT), first order shear deformation theory (FSDT), higher order shear deformation theory (HSDT) of Reddy and exact three dimensional elasticity theory wherever applicable. The results predicted by present theory are in good agreement with those of higher order shear deformation theory and the elasticity theory.

Electron Collision Cross Sections for the TRIES Molecule and Electron Transport Coefficients in TRIES-Ar and TRIES-O2 Mixtures

  • Tuoi, Phan Thi;Tuan, Do Anh;Hien, Pham Xuan
    • Journal of the Korean Physical Society
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    • 제73권12호
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    • pp.1855-1862
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    • 2018
  • A reliable set of low-energy electron collision cross sections for the triethoxysilane (TRIES) molecule was derived based on the measured electron transport coefficients for a pure TRIES molecule by using an electron swarm method and a two-term approximation of the Boltzmann equation. The electron transport coefficients calculated using the derived set are in good agreement with experimental value over a wide range of E/N values (ratio of the electric field E to the neutral number density N). The present electron collision cross section set for the TRIES molecule, therefore, is the most reliable so far for plasma discharges and for materials processing using the TRIES molecule. Moreover, the electron transport coefficients for the TRIES-Ar and the $TRIES-O_2$ mixtures were also calculated and analyzed over a wide range of E/N for the first time.

Analysis of Bone Fixation Methods in Digital Replantation

  • Lee, Seung Woo;Lee, Dong Chul;Kim, Jin Soo;Roh, Si Young;Lee, Kyung Jin
    • Archives of Plastic Surgery
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    • 제44권1호
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    • pp.53-58
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    • 2017
  • Background Adequate fixation of replanted digits is essential not only for short-term healing but for long-term function. Various bony fixation methods using Kirschner (K-) and intraosseous wire are available in replantation. We examined clinical and radiographic outcomes of fixation methods on bone union after digital replantation. Methods A single institutional retrospective review identified 992 patients who had undergone 1,247 successful replantations between July 2009 and September 2015. Exclusion criteria included amputations of the distal phalanx, comminuted fractures, and intra-articular fractures. Patients were classified according to 5 categories of fixation methods: single K-wire, double longitudinal K-wires, cross K-wires, wire with, and wire without K-wire support. Bone union was evaluated by 5-month postoperative X-ray and fixation outcomes were compared across the 5 groups. Results The exclusion criteria were applied, and 88 patients with 103 replanted digits remained for analysis. Single K-wire fixation was used in 40 digits, double longitudinal K-wires in 30, and cross fixation in 14. Wire with and without K-wire support was required in 15 and 4 digits. Nonunion was observed in 32 digits (31.1%), of which 13 required additional operations such as bone graft or corrective osteotomy. The highest percent of nonunion was observed after cross fixation (35.7%) and the lowest after wire alone (25.0%). Conclusions In this study, contrary to general knowledge, we found that single K-wire fixation was not associated with poorer outcomes. Successful bone union outcomes may be achieved by careful selection of bone fixation methods. This study provides useful information for planning bone fixation in digital replantation.