• Title/Summary/Keyword: Transitional Flow

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New Techniques for the Detection of the Malignant Cells in Urine Cytology (요 세포검사의 최근 검사기법)

  • Gong, Gyung-Yub
    • The Korean Journal of Cytopathology
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    • v.17 no.1
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    • pp.18-26
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    • 2006
  • Transitional cell carcinoma of the urinary bladder is common in the genitourinary tract. The gold standard for the diagnosis of bladder cancer has been cystoscopy, along with urine cytology. Cystoscopy is an invasive and relatively expensive technique. By comparison, urine cytology is easy to perform and specific for a diagnosis of bladder cancer, although less sensitive, especially in low-grade tumors. For this reason, there has been a need for superior noninvasive technology to increase our confidence in being able to detect bladder cancer. There are many reports of the various urinary tests that are available to facilitate the diagnosis. In this article, I reviewed the literature on urinary markers and tests that may be clinically useful, including fluorescence in situ hybridization, uCyt+/Immunocyte, the $BTA^{(R)}$ test, the NMP 22TM, the $FDP^{(R)}$ test, the telomerase activity test, the HA and HAse tests, and flow cytometry. Most of these tests have a higher sensitivity and specificity than cytology. However, urine cytology has the highest specificity, especially in individuals with a high-grade tumor. We conclude that no urinary markers or tests can replace the role of cystoscopy along with cytology in the diagnosis of transitional cell carcinoma of the bladder. However, some markers could be used adjunctively to increase the diagnostic accuracy during screening or during the postoperative follow-up examination of patients with bladder cancer.

A Study on Industrial Development Direction at Transitional Periods of Industrial Structure in Chungcheongbuk-do Region (산업구조 전환기 충북지역 산업의 발전방향)

  • 한주성
    • Journal of the Economic Geographical Society of Korea
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    • v.6 no.2
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    • pp.293-306
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    • 2003
  • This paper aims to clarify the change in industrial structure and industry itself, and makes suggestions for the industrial development direction at transitional periods in the Chungcheongbuk-do(province) region. Because profits of regional gross production in Chungcheongbuk-do region flow out of the region, basic industries must be brought up. For this phenomenon, main manufacturing must be developed for the industrial power of the next generation of high added values that combined with digital industry; the petrochemistry, semiconductor industry as major type of industry, and automobile industry as minor type of industry. Also for supporting industry, education service, health and welfare, research and development services that are knowledge-based service industries in Chungcheongbuk-do region, must be formated the network among corporations and constructed regional innovation system linked with educational institutions, precision chemistry industry and biology technology as major type of industry, and precision machinery and tools industry as minor type of industry.

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A Study On the Transformation of types of Windows and Doors with Full-Openable Bay size in Korean Buddhist Temples (사찰불전의 전간개방 창호 형식변화에 관한 연구)

  • 곽동영;조영화
    • Journal of the Korean housing association
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    • v.9 no.1
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    • pp.11-19
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    • 1998
  • A transitional trend of architectural elements which would happen naturally in a building may be a cue to the changes of the times. In this respect, this study is to investigate the transformation of types of windows and doors with the full-openable bay size in Korean Buddhist Temples and search for transitional process on types of windows and doors according to the flow of the times. As the results of this study, the following conclusion could be obtained. 1. The type of bunhap(connected door frame) Deul E-Yul-Gae doors + Deul E-Yul-Gas (life up) single windows would be changed from windows of a bay just beside a on the transition that the whole would be altered into the same type. 2. The type of Bunhap (connected door frame)Deul E-Yul-Gae doors + Bunhap (connected door frame) Deul E-Yul-Gae doors would be changed into Bunhap swinging doors that the whole of windows and doors could be opend very easily. 3. The type of Bunhap swinging doors + Bunhap swinging doors would be seen in the transition that windows and doors would be altered separately due to the exchange from window and doors of one of a middle bay or a bay just beside a middle bay to swinging doors and etc.

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A Study on Flow Characteristics of Two-Dimensional Backward-Facing Step by CFD (CFD에 의한 2차원 후향계단에서의 재부착 유동특성에 관한 연구)

  • 이영호
    • Journal of Advanced Marine Engineering and Technology
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    • v.23 no.1
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    • pp.9-18
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    • 1999
  • The present study is aimed to investigate flow characteristics of two-dimensional backward-fac-ing step by numerical approach. A convection conservation difference scheme based upon SOLA algorithm is used for the solution of the two-dimensional incompressible Navier-Stokes equations to simulate the laminar transitional and trubulent flow conditions at which the experimental data can be available for the backlward-facing step. The twenty kinds of reynolds number are used for the calculations. In an effort to demonstrate that the reported solutions are dependent on the mesh refinement computations are performed on seven different meshes of uniformly increasing refinement. also to investigate the result of inflow dependence two kinds of the inflow profile are chosen for the laminar flow. Irregular grid is adopted to minimize the errors on the satis-faction fo the discretized continuity. As criterion of benchmarking the result of numerical simula-tion reattachment lengthis used for the selected Reynolds numbers. The results of the present study prove the fact that the numerical predictions agree well with the experimental data and the flow characteristics are shown at the backward-facing step.

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Low Strain Rate Flame Extinction Characteristic of Oxygen Enhanced Opposed Flow Partially Premixed Flame in a Mesoscale Channel (채널 내부 대항류 산소부화 부분예혼합 화염의 저신장율 소화특성)

  • Lee, Min Jung;Kim, Nam Il
    • 한국연소학회:학술대회논문집
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    • 2014.11a
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    • pp.243-244
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    • 2014
  • The opposed flow flame in a mesoscale channel was constructed to observe the flame stabilization behaviors at low strain rate conditions (<$10s^{-1}$). The purpose of this study is to get the overall flame behaviors of partially premixed flames with oxygen enhanced conditions at low strain rates. The oxygen ratio in oxidizer was changed from 18 to 30 %. Conclusively, the flame extinction limit approached to about $1s^{-1}$, and divided into three representative regimes corresponding to self propagating flame, transitional flame, quenching flame regimes.

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Experimental Study on the Effect of Inlet Guide Vane of a Centrifugal Compressor (입구 안내익 영향으로 인한 원심 압축기 성능특성 시험연구)

  • Cha, Bong-Jun;Park, Jong-Ho
    • The KSFM Journal of Fluid Machinery
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    • v.5 no.3 s.16
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    • pp.46-53
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    • 2002
  • This paper reports an experimental investigation on a centrifugal compressor with the adjustable inlet guide vane. The compression system is composed of a radial impeller, a vaneless diffuser, and an IGV. The results have shown that surge line on the performance map is affected by the amount of prewhirl and the prewhirl has an effect on transient region between rotating stall and surge. The surge lines have been shifted toward the lower flow region with the increased positive prewhirl and the higher flow region with the increased negative prewhirl. During the unsteady performance test, it was also found that the transient region was reduced with the increased negative prewhirl, and weak signals of rotating stall were detected just before surge as the positive prewhirl was increased.

Steady and Unsteady Operating Characteristics of Supersonic Exhaust Diffuser for Altitude Simulation (고도모사용 초음속디퓨져의 정상 및 천이작동특성)

  • Park, Byung-Hoon;Ki, Wan-Do;Lim, Ji-Hwan;Yoon, Woong-Sup
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2006.11a
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    • pp.344-352
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    • 2006
  • Evacuation performance, starting transient, and plume blowback at diffuser breakdown of a straight cylindrical supersonic exhaust diffuser with no externally supplied secondary flow are investigated. Pressure records in the transitional periods are measured by a small-scale cold-gas simulator. Flow-fields evolving in the diffuser-type ejector are solved by preconditioned Favre-averaged Navier-Stokes equations with a low-Reynolds number $k-{\varepsilon}$ turbulence model edited for turbulence compressibility effects. The present RANS method is properly validated with measured static wall pressure distributions and evacuation level at steady operation as well as the pressure records during the transition regime.

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A Study on the Metal Transfer Considering Fluid Flow in GMAW (가스 메탈 아크 용접에서 유체 유동을 고려한 금속 이행에 관한 연구)

  • 박기영;이세헌;엄기원
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.4
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    • pp.148-155
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    • 1998
  • It is commonly known that, in GMAW, the characteristics of metal transfer and the size of molten drop are highly dependent on the welding current. These changes in the characteristics of metal transfer has a considerable effect on the weld quality, and a lot of studies have been made on metal transfer modes for that reason. In this study, two cases were investigated; the one in which the metal transfer proceeds with gravitational force, surface tension, and no electromagnetic force, and the other in which the process has electromagnetic term in addition, where the current density in the fluid has been assumed to have Gaussian distribution on any given cross-section and it acts vertically. Using fluid flow analysis, this study has observed the whole process of the development and break-up of the molten drop, and it also showed that transitional processes, drop rate, and the drop size in each metal transfer mode can be estimated.

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TRANSITIONAL FLOW ANALYSIS OVER DOUBLE COMPRESSION RAMP WITH NOSE BLUNTNESS IN SUPERSONIC FLOW (초음속 이중 압축 램프의 앞전 곡률에 따른 천이 유동 해석)

  • Shin, Ho Cheol;Sa, Jeong Hwan;Park, Soo Hyung;Byun, Yung Hwan
    • Journal of computational fluids engineering
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    • v.20 no.4
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    • pp.36-43
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    • 2015
  • Accurate prediction of supersonic transition is required for the heat transfer estimation over supersonic double compression ramp flows. Correlation-based transition models were assessed for a supersonic double ramp problem. Numerical results were compared with experimental data from RWTH Aachen University. A parametric study on the nose bluntness was performed using a selected transition model. As the nose bluntness increases, the boundary layer thickness is increased and the triple point of shock interactions moves downstream. The peak magnitude of the heat transfer is consequently decreased with the nose bluntness.

Flow over a Circular Cylinder in Three-Dimensional Transitional Regimes (삼차원 천이영역에서 원형 실린더 주위의 유동)

  • Kim, Jin-Sung;Choi, Hae-Cheon
    • Proceedings of the KSME Conference
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    • 2003.11a
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    • pp.956-961
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    • 2003
  • Direct numerical simulations of flow over a circular cylinder are performed at two different Reynolds numbers (Re=220 and 300) that correspond to three-dimensional instabilities of mode A and mode B, respectively, to investigate the characteristics of drag and lift at these Reynolds numbers. The drag and lift coefficients are measured locally along the spanwise direction and their characteristics are studied in detail. The variation of total drag in time is large at Re=220, and the total drag becomes minimum when vortex dislocation occurs in the wake. The drag and lift variations in space are also closely associated with the evolution of vortex dislocation at this Reynolds number. At Re=300, vortex dislocation is not found in the wake and temporal variations of drag and lift are much smaller than those at Re=220, but their spatial variations are quite large due to the near-wake secondary vortices existing in the mode B instability.

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