• Title/Summary/Keyword: Temporal region

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Evaluation of the CALPUFF Model Using Improved Meteorological Fields in Complex Terrain of East Sea Coast (동해안의 복잡지형에서 기상장 개선에 따른 CALPUFF 모델의 평가)

  • Lee, Chong-Bum;Kim, Jea-Chul
    • Journal of Korean Society for Atmospheric Environment
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    • v.25 no.1
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    • pp.15-25
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    • 2009
  • Donghae city is one of the most representative cement industrial city in Korea. The area is faced with the East Sea to the East and with high montane region of Tae-Back mountain range to the West. Many pollutant sources of air pollution are located near the coast, but the largest point sources of the region are located at the bottom of the mountain area in Donghae city. The local wind is highly affected by local topography and plays an important role in transport and dispersion of contaminants from the pollution sources. This study was designed to evaluate enhancement of MM5 predictions by using Four Dimensional Data Assimilation (FDDA), the SONDE data and the national meteorological station, data only. The alternative meteorological fields predicted with and without FDDA were used to simulate spatial and temporal variations of NOx in combined with Atmospheric Dispersion Models (CALPUFF). For the modeling domain, the alternative meteorological fields with 1.1 km spatial resolution were interpolated to the CALMET with 0.5 km resolution. The vertical layers set to have 35 and 12 layers for MM5 and CALPUFF, respectively. MM5 with the FDDA did not resulted in significant improvement of meteorological field prediction in Donghae region, which is primarily because of complex geography and wind scheme. The result of CALPUFF, however, showed reduction of uncertainty errors by using the interpolation scheme of the actual measurement data.

Meteorological Characteristics in the Ulsan Metropolitan Region: Focus on Air Temperature and Winds (울산지역의 기상 특성: 기온과 바람을 중심으로)

  • Oh, Inbo;Bang, Jin-Hee;Kim, Yangho
    • Journal of Korean Society for Atmospheric Environment
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    • v.31 no.2
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    • pp.181-194
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    • 2015
  • Spatial-temporal meteorological features of the Ulsan metropolitan region (UMR) were analyzed using observations and high-resolution numerical modeling. Long-term trend analysis (1970~2013) showed a significant increase of $0.033^{\circ}Cyr^{-1}$ in the 5-year moving average temperature, although detailed short-term features varied, whereas wind speed and relative humidity over the same period displayed clear decreases of $-0.007ms^{-1}$ and $-0.29%yr^{-1}$, respectively. These trends indicate the effects of regional climate change and urbanization in the UMR. Seasonal variations averaged for the most recent three years, 2011~2013, showed that temperatures in three different regions (urban/industrial, suburban, coastal areas) of the UMR had similar seasonality, but significant differences among them were observed for a certain season. Urban and industrial complex regions were characterized by relatively higher temperatures with large differences (max.: $3.6^{\circ}C$) from that in the coastal area in summer. For wind speed, strong values in the range from 3.3 to $3.9ms^{-1}$ occurred in the coastal areas, with large differences clearly shown between the three regions in September and October. Diurnal variations of temperature were characterized by pronounced differences during the daytime (in summer) or nighttime (in winter) between the three regions. Results from the WRF modeling performed for four months of 2012 showed large variations in gridaverage temperature and winds in the UMR, which displayed significant changes by season. Especially, a clear temperature rise in the urban center was identified in July ($0.6^{\circ}C$ higher than nearby urban areas), and overall, relatively weak winds were simulated over urban and inland suburban regions in all seasons.

Electrical Detection of Ear Acupuncture Points and Musculoskeletal Pain (경혈탐측기에 반응한 이혈(耳穴)과 신체 동통 부위와의 관계 연구)

  • Kang, Mun-Su;Park, Hyun-Chul;Kim, Lak-Hyung;Yu, Jeong-Suk;Song, Beom-Yong
    • Journal of Acupuncture Research
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    • v.24 no.6
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    • pp.187-193
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    • 2007
  • Objectives : The objectives of this study were to investigate the relationship between electrical detection of ear acupuncture points and musculoskeletal pain. Methods : 18 adults who have musculoskeletal pain without trauma factorsparticipated in this study. They answered the questionnaire and their ear acupuncture points were examined with electrical detectors. We analyzed the relationship between electrical detection of ear acupuncture points and musculoskeletal pain with concordance rate and validity. Results : Total concordance rates of the head region was 68.00%(questionnaire) 32.08%(investigation), that of vertebral region was 67.86%, 59.38%, that of both upper limbs was 86.67%, 39.69%, and that of both lower limbs was 50.00%, 23.46%. The true positive rate was 0.704, the true negative rate was 0.492, the false positive rate was 0.508, and the false negative rate was 0.296 in the validity test. In the head, two concordance rates of the temporal and occipital regions were relatively higher than those of the parietal and frontal regions. In the vertebral region, two concordance rates of the cervical and lumbar regions were relatively higher than those of the thoracic and sacrum regions. In the upper limb, two concordance rates of the shoulder and shoulder joints were relatively higher than those of the others. In the lower limb, concordance rates of investigation were relatively low at all areas. The right lower limb was relatively higher than the left in concordance rates of the questionnaire. Conclusions : The results suggest that electrical detection of ear acupuncture points can be used in the diagnosis and treatment of musculoskeletal pain.

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Dynamic PIV Measurements of Wake behind a Rotationally Oscillating Circular Cylinder (주기적으로 회전진동하는 원주 후류의 Dynamic PIV 속도장 측정)

  • Lee, Jung-Yeop;Lee, Sang-Joon
    • 한국가시화정보학회:학술대회논문집
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    • 2007.11a
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    • pp.134-137
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    • 2007
  • The temporal evolution of wake behind a circular cylinder oscillating rotationally with a relatively high forcing frequency has been investigated experimentally using a dynamic PIV technique. Experiments were carried out with varying the frequency ratio $F_R\;(=f_f/f_n)$ in the range from 0.0 (stationary) to 1.6 at oscillation amplitude of ${\theta}_A=30^{\circ}$ and Reynolds number of $Re=4.14{\times}10^3$. Depending on the forcing condition ($F_R$), the flow was divided into three regimes; non-lock-on ($F_R=0.4$), transition ($F_R=0.8$, 1.6) and lock-on regimes ($F_R=1.0$) with markedly different flow structure in the near-wake region behind the cylinder. When the frequency ratio was less than 1.0 ($F_R{\le}1.0$), the rotational oscillatory motion of the cylinder decreased the length of the vortex formation region and enhanced the mutual interaction between large-scale vortices across the wake centerline. The entrainment of ambient fluid seemed to play an important role in controlling the near-wake flow and shear-layer instability. However, the flow characteristics changed markedly beyond the lock-on flow regime ($F_R=1.0$) due to high-frequency forcing. At $F_R=1.6$, the mutual interactions between the vortices shed from both sides of the cylinder were not so strong. Thereby, the flow entrainment and momentum transfer into the wake center region were reduced. In addition, the size of the large-scale vortices decreased since the lateral extent of the wake was suppressed.

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Numerical Study of Wavy Film Flow on Vertical Plate Using Different Turbulent Models (난류 모형에 따른 수직 평판 위 파동 액막류의 수치해석 연구)

  • Min, June Kee;Park, Il Seouk
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.38 no.5
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    • pp.373-380
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    • 2014
  • Film flows applied to shell-and-tube heat exchangers in various industrial fields have been studied for a long time. One boundary of the film flow interfaces with a fixed wall, and the other boundary interfaces with a gaseous region. Thus, the flows become so unstable that wavy behaviors are generated on free surfaces as the film Reynolds number increases. First, high-amplitude solitary waves are detected in a low Reynolds number laminar region; then, the waves transit to a low-amplitude, high frequency ripple in a turbulent region. Film thickness is the most significant factor governing heat transfer. Since the wave accompanied in the film flow results in temporal and spatial variations in film thickness, it can be of importance for numerically predicting the film's wavy behavior. In this study, various turbulent models are applied for predicting low-amplitude ripple flows in turbulent regions. The results are compared with existing experimental results, and finally, the applied turbulent models are appraised in from the viewpoint of wavy behaviors.

Analysis of Porcine $\beta$-casein Gene Promoter by Site-directed Mutagenesis

  • Chung, Hee-Kyoung;Seong, Hwan-Hoo;Im, Seok-Ki;Lee, Hyun-Gi;Kim, Soon-Jeung;Lee, Poongyeong;Lee, Yun-Keun;Chang, Won-Kyong;Moosik Kwon
    • Proceedings of the Korean Society of Embryo Transfer Conference
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    • 2002.11a
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    • pp.71-71
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    • 2002
  • Promoters for milk proteins have been used far producing transgenic animals due to their temporal and spatial expression patterns. ${\beta}$-casein, a calcium-sensitive casein, is a major milk protein that corresponds ca. 30 per cent of total milk protein. Expression of ${\beta}$-casein is controlled by lactogenic hormones such as prolactin (PRL), composite response elements (CoREs) and transcription factors. CoREs are clusters of transcription factor binding sites containing both positive and negative regulatory elements. ${\beta}$-casein gene promoter contains various regions (CoREs) for gene transcription. We analyzed the promoter region by mutagenesis using exonuclease III and linker-scanning. Transcription control elements usually are positioned in 5'-flanking region of the gene. However, in some cases, these elements are located in other regions such as intron 1. The nucleotide sequences of ${\beta}$-casein promote. region has been reported (E12614). However, the properties of the promoter is not yet clear. In this study, we plan to investigate the properties of cis-regulating elements of porcine ${\beta}$-casein by mutation analysis and expression analysis using dual-luciferase repoter assay system.

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Study on the Characteristics of Performance and Exhaust Emissions of 3-Chamber GDI Engine (3-연소실형 GDI Engine의 성능 및 배기 배출물 특성에 관한 연구)

  • 김봉수;정남훈;진선호;배종욱
    • Journal of Advanced Marine Engineering and Technology
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    • v.26 no.1
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    • pp.37-47
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    • 2002
  • Recently gasoline direct injection method has been applied to gasoline engine to reduce fuel consumption rate by controlling fuel air mixture on lean condition by means of stratified charging, and to reduce simultaneously. Pollutant emissions especially NOx and CO by lowering the combustion temperature. But difficulty of controling local fuel air ratio at ignition area in flammability limit unavoidably appeared, because it is merely controlled by injection timing with spatial and temporal distribution of fuel mixture. In this study, the authors devised a uniquely shaped combustion chamber so called three-chamber GDI engine, intended to keep the more reliable fuel air ratio at ignition area. The combustion chamber is divided into three regions. The first region is in the rich combustion division, where the fuel is injected from the fuel injection valve and ignited by the spark plug. The second region is in the lean combustion division, where the combustion gas from the rich combustion division flows out and burns on lean condition. And the last region is in the main combustion division ie in the cylinder, where the gas from the above two combustion divisions mixed together and completes the combustion during expansion stroke. They found that the stable range of operation of three-chamber GDI engine on low-load condition exists in the lean area of average equivalence ratio. And they also found that the reformed engine reveals less specific fuel consumption and less pollutant emissions compared with conventional carburettor type gasoline engine.

Past Block Matching Motion Estimation based on Multiple Local Search Using Spatial Temporal Correlation (시공간적 상관성을 이용한 국소 다중 탐색기반 고속 블록정합 움직임 추정)

  • 조영창;남혜영;이태홍
    • Journal of Korea Multimedia Society
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    • v.3 no.4
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    • pp.356-364
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    • 2000
  • Block based fast motion estimation algorithm use the fixed search pattern to reduce the search point, and are based on the assumption that the error in the mean absolute error space monotonically decreases to the global minimum. Therefore, in case of many local minima in a search region we are likely to find local minima instead of the global minimum and highly rely on the initial search points. This situation is evident in the motion boundary. In this paper we define the candidate regions within the search region using the motion information of the neighbor blocks and we propose the multiple local search method (MLSM) which search for the solution throughout the candidate regions to reduce the possibilities of isolation to the local minima. In the MLSM we mark the candidate region in the search point map and we avoid to search the candidate regions already visited to reduce the calculation. In the simulation results the proposed method shows more excellent results than that of other gradient based method especially in the search of motion boundary. Especially, in PSNR the proposed method obtains similar estimate accuracy with the significant reduction of search points to that of full search.

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Hydroacoustic Survey of Spatiotemporal Stability and Distribution of Demersal Fish Aggregations in the Coastal Region (수산 음향 기법을 이용한 연안 저서 어군의 시.공간 분포 및 안정성 조사)

  • Kang, Dong-Hyug;Lee, Chang-Won;Cho, Sung-Ho;Myoung, Jung-Goo
    • Ocean and Polar Research
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    • v.30 no.1
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    • pp.79-87
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    • 2008
  • Hydroacoustic technique was used to analyze spatiotemporal stability and distribution of demersal fish aggregations in the coastal region to overcome some limitations of the existing methods such as net and diving. The survey was carried out in the Baekeum Bay on the south coast of Korea in January 2007. The bottom depth in the study site ranges from 7 to 25 m. In order to outline aggregations of demersal fish initial scanning using 200 kHz split-beam transducer was randomly conducted over the large area. Having detected fish aggregation in the specific region, intensive acoustic survey of irregular star pattern was carried out along 14 transects across the area in question. The results of the acoustic survey show that all demersal fish aggregations are concentrated about 5 m from sea bottom having a slight slope and remain steady with no spatial or temporal variations during acoustic survey. The hydroacoustic method used in this study offers a new approach to understand vertical and horizontal distribution, spatiotemporal stability, and biomass estimate of demersal fish aggregations in coastal regions. Additionally, the number of individual fish estimated from in situ acoustic target strength data can be used to understand the standing stock of demersal fish aggregation.

Effect of Korean Red Ginseng Supplementation on Ocular Blood Flow in Patients with Glaucoma

  • Kim, Na-Rae;Kim, Ji-Hyun;Kim, Chan-Yun
    • Journal of Ginseng Research
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    • v.34 no.3
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    • pp.237-245
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    • 2010
  • The purpose of this study was to evaluate the effect of Korean red ginseng (KRG) on ocular blood flow in patients with glaucoma. In a prospective, randomized, placebo-controlled, double-masked crossover trial, 36 patients with open-angle glaucoma were consecutively recruited. Subjects were randomly assigned into two groups. Group A received 1.5 g KRG, administered orally three times daily for 12 weeks, followed by a wash-out period of 8 weeks and 12 weeks of placebo treatment (identical capsules filled with 1.5 g corn starch). Group B underwent the same regimen, but took the placebo first and then KRG. Blood pressure, heart rate, and intraocular pressure were measured at baseline and at the end of each phase of the study. Visual field examination and ocular blood flow measurements by the Heidelberg Retina Flowmeter were performed at baseline and at the end of each phase of the study. Changes in blood pressure, heart rate, intraocular pressure, visual field indices, and retinal peripapillary blood flow were evaluated. Blood pressure, heart rate, intraocular pressure, and visual field indices did not change after placebo or KRG treatment. After KRG treatment, retinal peripapillary blood flow in the temporal peripapillary region significantly improved (p=0.005). No significant changes were found in retinal peripapillary blood flow in either the rim region or the nasal peripapillary region (p=0.051 and 0.278, respectively). KRG ingestion appears to improve retinal peripapillary blood flow in patients with open-angle glaucoma. These results imply that KRG ingestion might be helpful for glaucoma management.