• Title/Summary/Keyword: Onset Condition

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A Suggestion for Definition of El Niño/La Niña (엘니뇨/라니냐 정의에 대한 제언)

  • Son, Hye-Young;Kug, Jong-Seong;Yeh, Sang-Wook;Kim, Hyun-Kyung;Park, E-Hyung
    • Atmosphere
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    • v.23 no.1
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    • pp.63-71
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    • 2013
  • KMA is operationally monitoring El Ni$\tilde{n}$o and La Ni$\tilde{n}$a events, which have tremendous impacts on global climate. Many scientific studies have used to define onset of El Ni$\tilde{n}$o and La Ni$\tilde{n}$a events based on the moving average and persistency of SST indices, and KMA has adopted such definition. Though the definition has been widely accepted, in the operational aspect there is a critical problem to use moving average and condition for the persistence. Because the future values for the SST indices cannot be used in the operational monitoring, the onset timing in El Ni$\tilde{n}$o and La Ni$\tilde{n}$a can be significantly delayed. We suggest here an appropriate definition of El Ni$\tilde{n}$o and La Ni$\tilde{n}$a events in the operational aspect. Instead of using the moving average and the condition for the persistence, the onset is defined based on NINO3.4 SST during last 3 months. In order to compare the new definition with the current KMA definition, we applied them to recent 60-years SST data. It is clear that the new definition can declare the onset timing of El Ni$\tilde{n}$o and La Ni$\tilde{n}$a several months earlier than that of the KMA definition. It suggest that the new definition is more appropriate to the operational monitoring on El Ni$\tilde{n}$o and La Ni$\tilde{n}$a.

Effects of both Subject Age and Onset of Warts Influence for Curing in Ultrasound Treatment (초음파 치료에서 연령과 사마귀 발생시기가 사마귀 치유에 미치는 효과)

  • Lee, Eun-Hwa;Jung, Jae-Kyoung;Hwang, Mi-Kyoung
    • Physical Therapy Korea
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    • v.4 no.2
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    • pp.51-58
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    • 1997
  • The object of this study were twofold, namely, to study on (1) effect of using ultrasound therapy for curing warts (2) any relation between a cure for warts and onset of warts, as well as subject age. Our subjects, composed of 22 people from age 12 to 49, were assigned to two groups, experimental group and control group. We experimented for 8 session on 12 people in the experimental group by using ultrasound therapy to observe any morphological change in the warts or disappearance of a pain. However, we did not cure warts in the other group, control group. The result of the study are as follows. (1) Ultrasound therapy has an effect on curing warts. (2) Neither condition, onset of warts or subject age, had no influence on a cure for warts.

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A Study on the Onset of Condensation in a Supersonic Nozzle of Constant Expansion Rate (팽창율이 일정한 초음속 노즐흐름의 응축개시에 관한 연구)

  • 김병지;권순범;이은수
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.14 no.2
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    • pp.463-469
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    • 1990
  • A rapid expansion of moist air of condensible gas through a supersonic nozzle gives rise to condensation of nonequilibrium and equilibrium processes. Because most of the effects of condensation on the flow are caused by process of nonequilibrium condensation, it is very important to know the onset. condition of nonequilibrium condensation. In the present study, the relation between the initial relative stagnation humidity and the onset Mach number, for the case of the similarity law suggested by Zierep and Lin. Furthermore, the present theoretical result number is compared with the experimental, numerical and other results.

Behavior of Tip Vortex in a Propeller Fan (프로펠러팬에서의 Tip Vortex 거동)

  • Kim, Sung-Hyup;Furukawa, Masato;Inoue, Masahiro
    • Proceedings of the KSME Conference
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    • 2004.11a
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    • pp.1377-1382
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    • 2004
  • Flow fields in a half ducted propeller fan have been investigated by three-dimensional Reynolds-averaged Navier-Stokes (RANS) simulations and a vortex core identification technique. The simulation at the design operating condition shows that the tip vortex onset point is located at 30 percent tip chord of the suction surface on the blade tip. There is no interaction between the tip vortex and the adjacent blade, so that the tip vortex smoothly convects to the rotor exit. However, the high vorticity in the tip vortex causes the wake and the tip leakage flow to be twined around the tip vortex and to interact with the pressure surface of the adjacent blade. This flow behavior corresponds well with experimental results by Laser Doppler Velocimetry. On the contrary, the simulation at the low-flowrate operating condition shows that the tip vortex onset point is located at the 60 percent tip chord of the suction surface. In contrast to the design operating condition, the tip vortex grows almost tangential direction, and impinges directly on the pressure surface of the adjacent blade.

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A Study on The Pulsating Combustion of Premixed Gas in a Tube with a Honeycomb (다공성 물질에 의한 예혼합기의 맥동연소에 관한 연구)

  • 권영필;이동훈;현길학
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.14 no.3
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    • pp.676-684
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    • 1990
  • This study is on the pulsating combustion of premixed gas in a Rijke type combustor made of a honeycomb flame holder in a tube. Modelling for the onset condition of the oscillation is made by the ratio of the acoustic power generation based on the analysis of heat transfer to the power loss due to the thermoviscous dissipation and radiation. Experiment is performed for the characteristics of acoustic, thermal and combustion. It is shown that the theoretical modelling for the oscillation may be used as a limit condition. And the combustion analysis for the acoustic power generation is needed for better prediction of the onset condition. Experimental result shows that, by pulsation, the flame length is shortened and the flame temperature is decreased with increase in the heat transfer coefficient. The NO$_{x}$ concentration in the exhaust gas is significantly reduced by pulsation and the concentration of unburned hydrocarbon shows a little increase.e.

Reproductive Maturity Onset and Tree Size in a Garcinia kola (Heckel) Coastal Humid Tropical Climate Plantation

  • Henry Onyebuchi Okonkwo;Olubunmi Ayokunle Koyejo;Joseph Okechukwu Ariwaodo;Nsien Iniobong Bruno
    • Journal of Forest and Environmental Science
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    • v.39 no.2
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    • pp.73-80
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    • 2023
  • Little is known of the life history of Garcinia kola; the objective of this study, therefore, was to assess the fruiting age and tree size of the species in a coastal humid tropical climate plantation condition. A total 103 trees were used in the study viz; 80 ten-year-old trees at reproductive maturity onset and 13 thirty-year-old trees with several cycles of reproduction that constitute two independent variables. Data collected were age of onset of flowering and size at reproductive maturity onset. Relative size at reproductive maturity onset (RSOM) was estimated as size at reproductive maturity onset (SOM) divided by asymptotic maximal size (AMS). Data analysis was conducted using pairwise t-test and principal component analysis (PCA). Reproductive maturity onset (flowering) was recorded in the ten-year-old stand eight (8) years after planting. Mean size at reproductive maturity onset (SOM) was height 5.32±1.7 m, dbh 0.11±0.03 m, total number of branches was 29.6±7.3, crown depth 5.24±1.05 m, crown diameter was 4.78±0.7 m, branch diameter 0.098±0.01 m, leaf length 0.13±0.02 m, leaf breadth 0.37±0.01 m, twig length 0.35±0.11 m and leaf per twig 6±0.84 and asymptotic maximal size (AMS) was height 19.85±0.76 m, dbh 0.95±0.09 m, total number of branches 62±5, crown depth 18.83±0.7 m, crown diameter 12.5±1.64 m, branch diameter 0.5±1.6 m, leaf length 0.16±0.023 m, leaf breadth 0.45±0.12 m, twig length 0.37±0.11 m and leaf per twig 19±7.5. Pairwise t-test analysis showed there was significant differences between SOM and AMS in all growth factors except leaf length, leaf breadth, and twig length. Highest relative size at reproductive maturity onset (RSOM) was recorded in leaf length 0.82, twig length 0.82, and leaf breadth 0.80, while, the lowest was branch diameter 0.11. Four components out of the total of eleven were extracted to explain the relationship in RSOM: Principal component one (PC1) explained 37.23%; PC2 26.4%, PC3 22.73%, and PC4 13.64%.

Differences of Onset Timing Between Vastus Medialis and Lateralis during Knee Isometric Contraction on Individuals with Genu Varum or Valgum (안굽이 및 밖굽이 무릎을 가진 젊은 성인들에게서 등척성 운동 시 안쪽넓은근과가쪽넓은근의 근수축 개시시간 차이)

  • Park, Seol;Lee, Woo-Jin;Park, Ji-Won
    • The Journal of Korean Physical Therapy
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    • v.26 no.1
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    • pp.9-14
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    • 2014
  • Purpose: The purpose of this study was to investigate how different knee alignments (genu varum and genu valgum) affected activations of quadriceps muscles with measurements of onset-time differences between vastus medialis and vastus lateralis during isometric contractions at both 30 and 60 degree knee flexion. Methods: Fifty-two adults (20 genu varum, 12 genu valgum, and 20 control) were enrolled in this study. Subjects with over 4cm distance between knee medial epicondyles were assigned to Genu varum, while subjects with over 4cm distance between ankles medial malleolus were considered as genu valgum group. Surface EMG was used to measure onset time of both vastus medialis and vastus lateralis during isometric contraction at 30 and 60 degree knee flexion. Results: The onset time of vastus lateralis was delayed in genu varum group, and that of vastus medialis was delayed in genu valgum group at both 30 and 60 degree knee flexions. Moreover, onset time difference at $30^{\circ}$ knee flexion between muscles was larger in genu valgum group than genu varum group. Conclusion: Subjects with genu varum or valgum activated quadriceps muscles with different orders pending on flexion degrees. Therefore, when quadriceps training program were planned to prevent pain or deformities, the findings that quadriceps were activated with different orders affected by knee alignments and joint degree at which trainings were performed, must be considered. If the selective training programs of quadriceps femoris are planned to prevent pain or deformities due to poor knee alignments, these should consider the subject's knee alignment condition.

Articulatory modification of /m/ in the coda and the onset as a function of prosodic boundary strength and focus in Korean

  • Kim, Sahyang;Cho, Taehong
    • Phonetics and Speech Sciences
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    • v.6 no.4
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    • pp.3-15
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    • 2014
  • An articulatory study (using an Electromagnetic Articulography, EMA) was conducted to explore effects of prosodic boundary strength (Intonational Phrase/IP versus Word/Wd), and focus (Focused/accented, Neutral, Unfocused/unaccented) on the kinematic realization of /m/ in the coda (${\ldots}$am#i${\ldots}$) and the onset (${\ldots}$a#mi${\ldots}$) conditions in Korean. (Here # refers to a prosodic boundary such as an IP or a Wd boundary). Several important points have emerged. First, the boundary effect on /m/s was most robustly observed in the temporal dimension in both the coda (IP-final) and the onset (IP-initial) conditions, generally in line with cross-linguistically observable boundary-related lengthening patterns. Crucially, however, in contrast with boundary-related slowing-down effects that have been observed in English, both the IP-final and IP-initial temporal expansions of Korean /m/s were not accompanied by an articulatory slowing down. They were, if anything, associated with a faster movement in the lip opening (release) phase (into the vowel). This suggests that the mechanisms underlying boundary-related temporal expansions may differ between languages. Second, observed boundary-induced strengthening effects (both spatial and temporal expansions, especially on the IP-initial /m/s) were remarkably similar to prominence (focus)-induced strengthening effects, which is again counter to phrase-initial strengthening patterns observed in English in which boundary effects are dissociated from prominent effects. This suggests that initial syllables in Korean may be a common focus for both boundary and prominence marking. These results, taken together, imply that the boundary-induced strengthening in Korean is different in nature from that in English, each being modulated by the individual language's prosodic system. Third, the coda and the onset /m/s were found to be produced in a subtly but significantly different way even in a Wd boundary condition, a potentially neutralizing (resyllabification) context. This suggests that although the coda may be phonologically 'resyllabified' into the following syllable in a phrase-medial position, its underlying syllable affiliation is kinematically distinguished from the onset.

Rupture of Papillary Muscle -Report of a Case- (유두근 파열 수술 치험 1례)

  • 박국양
    • Journal of Chest Surgery
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    • v.28 no.1
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    • pp.69-72
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    • 1995
  • A 69-year-old patient with rupture of anterolateral papillary muscle following non-Q-wave myocardial infarction is described. Transesophageal echocardiography was useful in making the diagnosis. Mitral valve replacement was performed 22 days after the onset of acute myocardial infarction. The patient was discharged in his good condition and coronary angiography is scheduled.

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