• Title/Summary/Keyword: Passage rate

Search Result 370, Processing Time 0.022 seconds

Characteristics of Smoke Propagation in Railway Tunnels with Rescue Station (구난역을 갖는 철도 터널 내부의 연기거동 특성)

  • Jang, Won-Cheol;Kim, Dong-Woon;Lee, Seong-Hyuk;Ryou, Hong-Sun
    • Fire Science and Engineering
    • /
    • v.23 no.4
    • /
    • pp.13-18
    • /
    • 2009
  • The main objective of the present study is to investigate smoke propagation in railway tunnels with rescue stations. In particular, based on measurement of HRR (heat release rate) for pool fires formed at different locations, the influence of fire source location on smoke behavior is examined. The fuel is n-heptane and pool fires are generated with a square length 4cm. With the use of MVHS (Modified Volumetric Heat Source) model for fire source, extensive numerical simulations are performed by using the commercial code FLUENT (Ver.6.3) Predicted smoke temperatures and smoke propagation are discussed. From numerical predictions, it is found that ventilation systems may be necessary in the railway tunnels because the smoke moves along the tunnel, and consequently it enters the non-accident tunnel. It is also confirmed that the cross-passage and fire protection wall systems contribute to control the smoke.

Targeting of COX-2 Expression by Recombinant Adenovirus shRNA Attenuates the Malignant Biological Behavior of Breast Cancer Cells

  • Tu, Bo;Ma, Ting-Ting;Peng, Xiao-Qiong;Wang, Qin;Yang, Hong;Huang, Xiao-Ling
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.20
    • /
    • pp.8829-8836
    • /
    • 2014
  • Background: Cyclooxygenase-2 (COX-2), considered to have tumor-promoting potential, is highly expressed in a variety of tumors, including breast cancer. Since the functions and action mechanisms of COX-2 in breast cancer have not been fully elucidated, in the present study, the effects of target inhibiting COX-2 with recombinant adenovirus Ad-COX-2-shRNA on malignant biological behavior were investigated in representative cell lines. Materials and Methods: Breast cancer MDA-MB-231 and MCF-7 cells were transfected with Ad-COX-2-shRNA and COX-2 expression was tested by RT-PCR and Western blotting. Changes in proliferation, apoptosis and invasion of breast cancer cells were detected with various assays including MTT, colony forming, flowcytometry and Transwell invasion tests. The expression of related proteins involved in the cell cycle, apoptosis, invasion and signaling pathways was assessed by Western blotting. Results: COX-2 expression was significantly reduced in both breast cancer cell lines infected with Ad-COX-2-shRNA, with obvious inhibition of proliferation, colony forming rate, G2/M phase passage and invasion, as well as induction of apoptosis, in MDA-MB-231 and MCF-7 cells, respectively. At the same time, proteins related to the cell cycle, anti-apoptosis and invasion were significantly downregulated. In addition, c-myc expression and phosphorylation activation of Wnt/${\beta}$-catenin and p38MAPK pathways were reduced by the Ad-COX-2-shRNA. Conclusions: COX-2 expression is associated with proliferation, apoptosis and invasion of breast cancer cells, and its mechanisms of action involve regulating expression of c-myc through the p38MAPK and Wnt/${\beta}$-catenin pathways.

Rumen Degradability and Post-ruminal Digestion of Dry Matter, Nitrogen and Amino Acids of Three Protein Supplements

  • Gao, Wei;Chen, Aodong;Zhang, Bowen;Kong, Ping;Liu, Chenli;Zhao, Jie
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.28 no.4
    • /
    • pp.485-493
    • /
    • 2015
  • This study evaluated the in situ ruminal degradability, and subsequent small intestinal digestibility (SID) of dry matter, crude protein (CP), and amino acids (AA) of cottonseed meal (CSM), sunflower seed meal (SFSM) and distillers dried grains with solubles (DDGS) by using the modified three-step in vitro procedure. The ruminal degradability and subsequent SID of AA in rumen-undegradable protein (RUP-AA) varied among three protein supplements. The result show that the effective degradability of DM for SFSM, CSM, and DDGS was 60.8%, 56.4%, and 41.0% and their ruminal fermentable organic matter was 60.0%, 55.9%, and 39.9%, respectively. The ruminal degradable protein (RDP) content in CP for SFSM, CSM, and DDGS was 68.3%, 39.0%, and 32.9%, respectively, at the ruminal solid passage rate of 1.84%/h. The SFSM is a good source of RDP for rumen micro-organisms; however, the SID of RUP of SFSM was lower. The DDGS and CSM are good sources of RUP for lambs to digest in the small intestine to complement ruminal microbial AA of growing lambs. Individual RUP-AA from each protein source was selectively removed by the rumen microorganisms, especially for Trp, Arg, His, and Lys (p<0.01). The SID of individual RUP-AA was different within specific RUP origin (p<0.01). Limiting amino acid was Leu for RUP of CSM and Lys for both RUP of SFSM and DDGS, respectively. Therefore, different protein supplements with specific limitations should be selected and combined carefully in growing lambs ration to optimize AA balance.

A COMPUTATIONAL ANALYSIS FOR OUTLET SHAPE DESIGN TO SUPPRESS FLOW RECIRCULATION IN A ROTATING-DISK CVD REACTOR (회전원판형 CVD 장치의 유동 재순환을 억제하는 출구부 형상 설계를 위한 전산해석)

  • Park, J.J.;Kim, K.;Kwak, H.S.
    • Journal of computational fluids engineering
    • /
    • v.18 no.4
    • /
    • pp.74-81
    • /
    • 2013
  • A numerical design analysis is conducted to search for an optimal shape of outlet in a rotating-disk CVD reactor. The goal is to suppress flow recirculation that has been found in a reactor having a sudden expansion of flow passage outside of the rotating disk. In order to streamline gas flow, the sidewall at which the flow in the Ekman layer is impinged, is tilted. The axisymmetric laminar flow and heat transfer in the reactor are simulated using the incompressible ideal gas model. For the conventional vertical sidewall, the flow recirculation forming in the corner region could be expanded into the interior to distort the upstream flow. The numerical results show that this unfavorable phenomenon inducing back flow could be dramatically suppressed by tilting the sidewall at a certain range of angle. The assessment of deviation in deposition rate based on the characteristic isotherm illustrates that the sidewall tilting may expand the domain of stable plug-like flow regime toward higher pressure. A physical interpretation is attempted to explain the mechanism to suppress flow recirculation.

Performance Analysis by CFD and Aerodynamic Design of 100kW Class Radial Turbine Using Waste Heat from Ship (선박 폐열을 이용한 100kW급 구심터빈 공력설계 및 CFD에 의한 성능해석)

  • Mo, Jang-Oh;Kim, You-Taek;Kim, Mann-Eung;Oh, Cheol;Kim, Jeong-Hwan;Lee, Young-Ho
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.35 no.2
    • /
    • pp.175-181
    • /
    • 2011
  • The purpose of this study is to secure the design data for the optimization of the radial turbine and heat cycle system, by using the CFD analysis technique and the design of 100kW class radial turbine applicable to waste heat recovery generation system for ship. Radial turbine was comprised of scroll casing, vane nozzle with 18 blades and rotor with 13 blades, and analysis grid was used to about 2.3 million. Mass flow rate and rotational speed was 0.5kg/s, 75,0000rpm, respectively. Eight kinds of inlet pressure was set between 195 and 620kPa. As the flow accelerated through the nozzle passage to the throat, the pressure level at the pressure and suction sides becomed similar to about Mach number of 0.35. When the inlet temperature and pressure was $250^{\circ}C$, 352kPa respectively, the isentropic efficiency and mechanical power showed the analysis results of 74% and 108kW.

A Study on Observation Characteristics by Sex shown in the process of Visual Appreciation of Space (공간의 시각적 이해과정에 나타난 성별 주시특성에 관한 연구)

  • Kim, Jong-Ha
    • Korean Institute of Interior Design Journal
    • /
    • v.22 no.5
    • /
    • pp.152-161
    • /
    • 2013
  • This study is about the visual appreciation by sex with the analysis of time range of observing data which was got through observation experiment with the space of lobby in hospitals. The observation data of the subjects who observed the space include the frequency and time, through which the process of visual appreciation could be evaluated with the definition of the frequency and the time of observation. First, the fact that men had higher frequency of observation than women means the former had more movement than the latter, and another fact of their fewer times can be understood as the time of their staying was shorter. That is, even though the men had more movements of sight, they showed the feature of staying shorter. Second, the rate high and low of observation frequency and times made it possible for observation characteristics to be defined as 'intensive search' 'active search' 'fixed concentration' and 'search wandering.' The definition of understanding this process of visual appreciation can be available for a frame of effective analysis of observation characteristics according to the passage of time. Third, the intense search is the case of 'high frequency' having the feature of high visual appreciation owing to the active visual actions for acquiring information. Men were found to have more intense search which decreased gradually as time passed, while women showed the feature of many times of intense search. Fourth, it was found that with many observation data in a certain range of time the subjects had fixed concentration, where women were found to have repetitive fixed concentration along with the change of observation time while men were seen to have more observation tendency for fixed concentration. Fifth, at the cross tabulation of frequency and times, men had the feature of dispersed visual appreciation while women had more distinction between fixation and movement, which revealed that there is surely the difference between men and women in the process of visual appreciation.

Studies on the Ecological Change of the Plant Community in the Erosion-Controlled and Rehabilitated Areas - During 9~26 Years After Erosion Control Works - (사방시공지 식물사회의 생태학적 변화에 관한 연구(V) - 사방시공 후 9~26년 간의 변화 -)

  • Lee, Hyun-Kyu
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.6 no.5
    • /
    • pp.59-69
    • /
    • 2003
  • Most denuded mountain areas in Korea were completely stabilized by the successful work of the 1st and 2nd 10-year Forest Development Plans which targeted the reforestation of denuded forest lands. The objectives of this study are (1) to estimate the depth of organic horizon in the soil profile, (2) to investigate the change of vegetation structure, (3) to estimate the change of biomass in the erosion controlled and rehabilitated mountain areas with the passage of time. This study was carried out as the 5th times. The first study began in the year of 1985, the second study was in the year of 1988, the third study was in the year of 1992, 4th was in the year of 1998 and 5th was in the year of 2002. The first study started in the study sites which elapsed 9 years after erosion control works. The results of the study were as follows : The increase rate of soil thickness was estimated to $Y_{(cm)}=2.906log_{(yr)}-3.2476(r^2=0.917)$ during 26 years after erosion control works. The important value of pines decreased to 14.7% on upper layer. But, the important value of alders. which did not plant on erosion control work increased to 27.1%. The decrease of whole crown projection indicates that pines. and alders were heavily injured by pine leaf gall midge in the year of 1993, 1995 years and Agelastica coerulea Baly in the year of 1986, 1987 years at Yoju-gun. The young growth of pines and alders not appeared on the soil surface which elapsed 26 years after erosion control works. On the lower layer, oaks occupied over 50% in I.V, RD, RC, RF. In process of years, the increase of biomass estimated to be $Y_{(t/ha)}={0.7505X_{(yr)}}^{1.6335}\;(r^2=0.9712)$ for 26 years after erosion control works.

Development of a Real Time Video Image Processing System for Vehicle Tracking (실시간 영상처리를 이용한 개별차량 추적시스템 개발)

  • Oh, Ju-Taek;Min, Joon-Young
    • International Journal of Highway Engineering
    • /
    • v.10 no.3
    • /
    • pp.19-31
    • /
    • 2008
  • Video image processing systems(VIPS) offer numerous benefits to transportation models and applications, due to their ability to monitor traffic in real time. VIPS based on wide-area detection, i.e., multi-lane surveillance algorithm provide traffic parameters with single camera such as flow and velocity, as well as occupancy and density. However, most current commercial VIPS utilize a tripwire detection algorithm that examines image intensity changes in the detection regions to indicate vehicle presence and passage, i.e., they do not identify individual vehicles as unique targets. If VIPS are developed to track individual vehicles and thus trace vehicle trajectories, many existing transportation models will benefit from more detailed information of individual vehicles. Furthermore, additional information obtained from the vehicle trajectories will improve incident detection by identifying lane change maneuvers and acceleration/deceleration patterns. The objective of this research was to relate traffic safety to VIPS tracking and this paper has developed a computer vision system of monitoring individual vehicle trajectories based on image processing, and offer the detailed information, for example, volumes, speed, and occupancy rate as well as traffic information via tripwire image detectors. Also the developed system has been verified by comparing with commercial VIP detectors.

  • PDF

Cell adaptation of KPEDV-9 and serological survey on porcine epidemic diarrhea virus(PEDV) infection in Korea (돼지 유행성설사바이러스 국내 분리주(KPED-9) 의 세포증식성 및 혈청학적 역학조사)

  • Kweon, Chang-hee;Kwon, Byung-joon;Kang, Yung-bai;An, Soo-hwan
    • Korean Journal of Veterinary Research
    • /
    • v.34 no.2
    • /
    • pp.321-326
    • /
    • 1994
  • Korean isolate, porcine epidemic diarrhea virus (KPEDV-9) was adapted through serial passages in vero cell. The viral yield reached up to $10^{5-6}$ $TCID_{50}/ml$ at the passage level of 90th. The cell adapted virus was characterized through genetic and morphological examinations. The RNA extracted from virus infected cell revealed the presence of RNA band with molecular size of >20Kb. The electron microscopic examination on purified virus showed the pleomorphic appearance of enveloped particles with 5-10nm surface projections, which fit with the shape of coronavirus. The etiological survey on swine diarrhea by immunofluorescence test(FA) indicated 17.5% positive rate on the PEDV infection. In addition, the incidence were detected both in piglets within two weeks old as well as fattening pigs. Serological survey by ELISA revealed the overall 45% positive result, thus, indicating the PEDV infection are widespread throughout this country.

  • PDF

Characteristics of Speech Breathing in de novo Idiopathic Parkinson's Disease during Passage Reading Tasks (De novo 특발성 파킨슨병 환자의 문단 읽기 과제에서의 호흡 특성)

  • Kim, Byung-Me;Sohn, Young-Ho;Baek, Seung-Jae;Lee, Phil-Hyu;Nam, Chung-Mo;Lee, Ji-Eun;Choi, Yae-Lin
    • Phonetics and Speech Sciences
    • /
    • v.3 no.1
    • /
    • pp.103-110
    • /
    • 2011
  • Idiopathic Parkinson's Disease patients' speech is hypokinetic dysarthria and their speech is possibly the consequence of impaired respiratory support. The purpose of this study was focused on the respiratory characteristics of speech breathing in de novo IPD who were not given prior vocal or anti-Parkinson treatment. A total of 40 subjects participated in the study: 20 de novo IPD patients between the ages of 50 and 80, and 20 normal subjects with similar age, height, and weight matches. Forced Expiratory Vital Capacity (FVC), Forced Expiratory Volume in 1 sec (FEV1) and $FEV_1$ as a percentage of FVC (FEV1/FVC) was measured with a PC-based spirometer (Cosmed). In addition, Maximum Phonation Time (MPT), Mean Airflow Rate (MFR), Subglottal Pressure (Psub) and the number of syllables produced per breath were measured with a Phonatory Aerodynamic System (Kay PENTAX). All subjects were asked to read a standardized Korean paragraph and the following measurements were obtained from the task. Results indicated no statistically significant differences in respiratory function (FEV1/FVC%) and aerodynamic function between the two groups, but the number of syllables per breath was significantly lower in the IPD patient group than in the normal group and it could be predicted by FVC and MFR. Therefore, the study shows that the MFR from the lungs during speech in de novo IPD patients is used inefficiently.

  • PDF