• 제목/요약/키워드: normalized k

Search Result 2,395, Processing Time 0.039 seconds

Ground-Motion Prediction Equations based on refined data for dynamic time-history analysis

  • Moghaddam, Salar Arian;Ghafory-Ashtiany, Mohsen;Soghrat, Mohammadreza
    • Earthquakes and Structures
    • /
    • v.11 no.5
    • /
    • pp.779-807
    • /
    • 2016
  • Ground Motion Prediction Equations (GMPEs) are essential tools in seismic hazard analysis. With the introduction of probabilistic approaches for the estimation of seismic response of structures, also known as, performance based earthquake engineering framework; new tasks are defined for response spectrum such as the reference criterion for effective structure-specific selection of ground motions for nonlinear time history analysis. One of the recent efforts to introduce a high quality databank of ground motions besides the corresponding selection scheme based on the broadband spectral consistency is the development of SIMBAD (Selected Input Motions for displacement-Based Assessment and Design), which is designed to improve the reliability of spectral values at all natural periods by removing noise with modern proposed approaches. In this paper, a new global GMPE is proposed by using selected ground motions from SIMBAD to improve the reliability of computed spectral shape indicators. To determine regression coefficients, 204 pairs of horizontal components from 35 earthquakes with magnitude ranging from Mw 5 to Mw 7.1 and epicentral distances lower than 40 km selected from SIMBAD are used. The proposed equation is compared with similar models both qualitatively and quantitatively. After the verification of model by several goodness-of-fit measures, the epsilon values as the spectral shape indicator are computed and the validity of available prediction equations for correlation of the pairs of epsilon values is examined. General consistency between predictions by new model and others, especially, in short periods is confirmed, while, at longer periods, there are meaningful differences between normalized residuals and correlation coefficients between pairs of them estimated by new model and those are computed by other empirical equations. A simple collapse assessment example indicate possible improvement in the correlation between collapse capacity and spectral shape indicators (${\varepsilon}$) up to 20% by selection of a more applicable GMPE for calculation of ${\varepsilon}$.

Effect of Oral Administration of DiakurTM (a Glucose and Electrolytes Additive) on Growth and Some Physiological Responses in Broilers Reared in a High Temperature Environment

  • Takahashi, Kazuaki;Akiba, Yukio
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.15 no.9
    • /
    • pp.1341-1347
    • /
    • 2002
  • An experiment was conducted to determine effects of oral administration of $Diakur^{TM}$ (an additive of glucose and electrolytes for young calves) on growth performance and some physiological responses in male broilers reared in a high temperature. A 2 by 3 factorial arrangement test of 2 temperatures (24 and $36^{\circ}C$) and 3 levels of oral administration of the glucose and electrolytes additive, $Diakur^{TM}$, (0, 150 and 300 mg/day/100 gBW) were applied in the experiment. Male broiler chicks (2 weeks of age) were assigned to six groups and received dietary and temperature treatments for 7 days. The additive of glucose and electrolytes was suspended with water and intubated into crop twice a day (08:00 and 17:00). Oral administration of the additive prevented decreases in food intake and growth rates in broilers due to exposure of the hot environment. Oral administration of the additive also improved a lowered electrolyte ($Na^+$ + $K^+$ - $Cl^-$) balance in plasma, low mitogenic response of blood mononuclear cell and an increase in glucose concentration due to exposure to the high environmental temperature. Oral administration of the additive increased rectal temperature regardless of environmental temperatures. On the other hand, blood pH, $pCO_2$ and $HCO_3$ - concentration, and plasma creatine kinase activity were not affected by the oral administration. The results suggested that oral administration of the glucose and electrolytes additive, $Diakur^{TM}$ during heat stress did not only prevent decrease in growth performance, but also normalized some physiological and immunological responses in male broilers.

EFFECT OF WALL PROXIMITY ON DRAG AND LIFT FORCES ON A CIRCULAR CYLINDER (벽 근접 효과에 의한 물체의 항력 양력 변화)

  • Park, Hyun-Wook;Lee, Chang-Hoon;Choi, Jung-Il
    • Journal of computational fluids engineering
    • /
    • v.17 no.3
    • /
    • pp.68-74
    • /
    • 2012
  • Near-wall effect on wakes behind particles is one of the important factors in precise tracking of particles in turbulent flows. However, most aerodynamic force models for particles did not fully consider the wall effect. In the present study, we focused on changes of hydrodynamic forces acting on a particle depending on wall proximity. To this end, we developed an immersed boundary method with multi-direct forcing incorporated to a fully implicit decoupling procedure for incompressible flows. We validate the present immersed boundary method through two-dimensional simulations of flow over a circular cylinder. Comprehensive parametric studies on the effect of the wall proximity on the drag and lift forces acting on an immersed circular cylinder in a channel flow are performed in order to investigate general flow patterns behind the circular cylinder for a wide range of Reynolds number (0.01 ${\leq}$ Re ${\leq}$ 200). As the cylinder is closer to the wall, the drag coefficient decreases while the lift coefficient increases with a local maximum. Maximum drag and lift coefficients for different wall proximities decrease with increment of Reynolds number. Normalized drag and lift coefficients by their maximum values show universal correlations between the coefficients and wall proximity in a low Reynolds number regime (Re ${\leq}$ 1).

Classification of Land Cover over the Korean Peninsula using MODIS Data (MODIS 자료를 이용한 한반도 지면피복 분류)

  • Kang, Jeon-Ho;Suh, Myoung-Seok;Kwak, Chong-Heum
    • Atmosphere
    • /
    • v.19 no.2
    • /
    • pp.169-182
    • /
    • 2009
  • To improve the performance of climate and numerical models, concerns on the land-atmosphere schemes are steadily increased in recent years. For the realistic calculation of land-atmosphere interaction, a land surface information of high quality is strongly required. In this study, a new land cover map over the Korean peninsula was developed using MODIS (MODerate resolution Imaging Spectroradiometer) data. The seven phenological data set (maximum, minimum, amplitude, average, growing period, growing and shedding rate) derived from 15-day normalized difference vegetation index (NDVI) were used as a basic input data. The ISOData (Iterative Self-Organizing Data Analysis), a kind of unsupervised non-hierarchical clustering method, was applied to the seven phenological data set. After the clustering, assignment of land cover type to the each cluster was performed according to the phenological characteristics of each land cover defined by USGS (US. Geological Survey). Most of the Korean peninsula are occupied by deciduous broadleaf forest (46.5%), mixed forest (15.6%), and dryland crop (13%). Whereas, the dominant land cover types are very diverse in South-Korea: evergreen needleleaf forest (29.9%), mixed forest (26.6%), deciduous broadleaf forest (16.2%), irrigated crop (12.6%), and dryland crop (10.7%). The 38 in-situ observation data-base over South-Korea, Environment Geographic Information System and Google-earth are used in the validation of the new land cover map. In general, the new land cover map over the Korean peninsula seems to be better classified compared to the USGS land cover map, especially for the Savanna in the USGS land cover map.

Compensation Method of Parameters to Evaluate a Sheilding Coefficient of Electromagnetic Induction Voltage (전자유도전압 차폐계수 산정을 위한 파라미터 보정 방법)

  • Lee, Sangmu;Choi, Mun Hwan;Cho, Pyung-dong
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2013.05a
    • /
    • pp.503-506
    • /
    • 2013
  • The shielding coefficient of a conductive length structure is calculated by a ratio of induced voltage with that structure to without that structure. The environments are different between with a structure and without a structure. Beside the corresponding structure, all the parameters related to induced voltage should be normalized to a presumable same environment conditions. Basically each parameter must be compensated, which is a bottom-up type method. In this case, some parameter is not possible to be so because of its unknowing function. Then as a calculated voltage already has all characteristics of parameters, seeking a ratio of calculated induction voltages themselves will include the compensation of all parameters automatically. This is a top-down method.

  • PDF

Analysis and Implementation of a Half Bridge Class-DE Rectifier for Front-End ZVS Push-Pull Resonant Converters

  • Ekkaravarodome, Chainarin;Jirasereeamornkul, Kamon
    • Journal of Power Electronics
    • /
    • v.13 no.4
    • /
    • pp.626-635
    • /
    • 2013
  • An analysis of the junction capacitance in resonant rectifiers which has a significant impact on the operating point of resonance circuits is studied in this paper, where the junction capacitance of the rectifier diode is to decrease the resonant current and output voltage in the circuit when compared with that in an ideal rectifier diode. This can be represented by a simplified series resonant equivalent circuit and a voltage transfer function versus the normalized operating frequency at varied values of the resonant capacitor. A low voltage to high voltage push-pull DC/DC resonant converter was used as a design example. The design procedure is based on the principle of the half bridge class-DE resonant rectifier, which ensures more accurate results. The proposed scheme provides a more systematic and feasible solution than the conventional resonant push-pull DC/DC converter analysis methodology. To increase circuit efficiency, the main switches and the rectifier diodes can be operated under the zero-voltage and zero-current switching conditions, respectively. In order to achieve this objective, the parameters of the DC/DC converter need to be designed properly. The details of the analysis and design of this DC/DC converter's components are described. A prototype was constructed with a 62-88 kHz variable switching frequency, a 12 $V_{DC}$ input voltage, a 380 $V_{DC}$ output voltage, and a rated output power of 150 W. The validity of this approach was confirmed by simulation and experimental results.

Investigation of the Central Carbon Metabolism of Sorangium cellulosum: Metabolic Network Reconstruction and Quantification of Pathway Fluxes

  • Bolten, Christoph J.;Heinzle, Elmar;Muller, Rolf;Wittmann, Christoph
    • Journal of Microbiology and Biotechnology
    • /
    • v.19 no.1
    • /
    • pp.23-36
    • /
    • 2009
  • In the present work, the metabolic network of primary metabolism of the slow-growing myxobacterium Sorangium cellulosum was reconstructed from the annotated genome sequence of the type strain So ce56. During growth on glucose as the carbon source and asparagine as the nitrogen source, So ce56 showed a very low growth rate of $0.23\;d^{-1}$, equivalent to a doubling time of 3 days. Based on a complete stoichiometric and isotopomer model of the central metabolism, $^{13}C$ metabolic flux analysis was carried out for growth with glucose as carbon and asparagine as nitrogen sources. Normalized to the uptake flux for glucose (100%), cells recruited glycolysis (51%) and the pentose phosphate pathway (48%) as major catabolic pathways. The Entner-Doudoroff pathway and glyoxylate shunt were not active. A high flux through the TCA cycle (118%) enabled a strong formation of ATP, but cells revealed a rather low yield for biomass. Inspection of fluxes linked to energy metabolism revealed that S. cellulosum utilized only 10% of the ATP formed for growth, whereas 90% is required for maintenance. This explains the apparent discrepancy between the relatively low biomass yield and the high flux through the energy-delivering TCA cycle. The total flux of NADPH supply (216%) was higher than the demand for anabolism (156%), indicating additional reactions for balancing of NADPH. The cells further exhibited a highly active metabolic cycle, interconverting $C_3$ and $C_4$ metabolites of glycolysis and the TCA cycle. The present work provides the first insight into fluxes of the primary metabolism of myxobacteria, especially for future investigation on the supply of cofactors, building blocks, and energy in myxobacteria, producing natural compounds of biotechnological interest.

Treatment of Cytomegalovirus-associated IgA Nephropathy by Deflazacort and Intravenous Immunoglobulin (거대세포바이러스와 연관된 IgA 신병증을 Deflazacort와 정맥 면역글로불린으로 치료한 1례)

  • Yoon, Seo-Hee;Ahn, Seung-Hee;NamGoong, Mee-Kyung
    • Childhood Kidney Diseases
    • /
    • v.12 no.2
    • /
    • pp.233-238
    • /
    • 2008
  • It has been suspected that various infections, including cytomegalovirus(CMV) infection, are associated with IgA nephropathy. In case of CMV infection, ganciclovir is known to be a treatment of choice for severe CMV infection in general. But ganciclovir has a lot of severe toxicity, so children with normal immunity are seldom treated by ganciclovir when CMV infection is suspected. On the other hand, intravenous immunoglobulin can also be used to treat CMV infection. We report a case of CMV-associated IgA nephrophaty, who was treated with deflazacort and Intravenous immunoglobulin therapy. An 11 years old boy suffered from gross hematuria for 3 days. He had proteinuria, thrombocytopenia(104,000/$mm^3$), antiplatelet antibody(+), impaired renal function and low serum albumin. His CMV serology was CMV-IgM/IgG(+/-) and urine CMV-PCR was positive. The renal histological findings revealed IgA nephropathy, WHO class II. His proteinuria persisted despite of deflazacort therapy(2.5 mg/kg/day). Later, intravenous immunoglobulin(1 g/kg) was administered twice. In two years, he showed no gross and microscopic hematuria, and his laboratory findings were also normalized.

Comparison of Abdominal Muscle Activity during Exercises Using a Sling and Swiss-ball

  • Kim, Byung-Kon;Lee, Myoung-Hee;Kim, Gi-Chul
    • The Journal of Korean Physical Therapy
    • /
    • v.25 no.3
    • /
    • pp.149-154
    • /
    • 2013
  • Purpose: Spinal instability due to weakness of abdominal muscles is one of the major causes that induces low back pain (LBP). The purpose of this study was to investigate any differences in abdominal muscle activity during curl up, roll out, and jack knife exercises using a swiss-ball or sling. Methods: Twenty healthy subjects were randomly assigned into either a swiss-ball exercise group (SBEG) or a sling exercise group (SEG). Subjects performed curl up, roll out and jack knife exercises using the swiss ball or sling. Activity of abdominal muscles (rectus abdominis and external oblique muscle) was assessed using surface EMG and normalized maximal voluntary isometric contraction (MVIC). The significance of differences between the sling exercise group and the swiss-ball exercise group was evaluated by the independent t-test. Results: These Results indicated that activities of rectus abdominis on right and left of the SEG during the curl up exercise were significantly greater than the SBEG. During the roll out exercise, activity of the abdominal muscle was not significantly different between the SEG and SBEG. In addition, during the jack knife exercise, activities of the right rectus abdominis and left external oblique muscle in the SEG were significantly greater than the SBEG. Conclusion: In conclusion, activity of the abdominal muscles was maximized when curl up and jack knife exercise were performed using the sling rather than the swiss-ball. Therefore, if increased activation of the abdominal muscle is the goal of an exercise program, curl up and jack knife exercises may be useful.

Identification of two common types of forest cover, Pinus densiflora(Pd) and Querqus mongolica(Qm), using the 1st harmonics of a Discrete Fourier Transform

  • Cha, Su-Young;Pi, Ung-Hwan;Yi, Jong-Hyuk;Park, Chong-Hwa
    • Korean Journal of Remote Sensing
    • /
    • v.27 no.3
    • /
    • pp.329-338
    • /
    • 2011
  • The time-series normalized difference vegetation index (NDVI) product has proven to be a powerful tool to investigate the phenological information because it can monitor the change of the forests with very high time-resolution, This study described the application of the DFT analysis over the 9 year MODIS data for the identification of the two types of vegetation cover, Pinus densiflora(Pd) and Querqus mongolica(Qm) which are dominant species of evergreen and broadleaved deciduous forest, respectively, The total number of samples was 5148 reference cycles which consist of 2160 Pd and 2988 Qm. They were extracted from the pixel-based MODIS scenes over the 9 years from 2000 to 2008 of South Korea. The DFT analysis was mainly focused on the 0th and $1^{st}$ harmonic components, each of which represents the mean value and the variation amplitude of the NDVI over the years, respectively. The $0^{th}$ harmonic values of the vegetation Pd and Qm averaged over the 9 years were 0.74 and 0.65, respectively. This implies that Pd has a higher NDVI than Qm. Similarly obtained $1^{st}$ harmonic values of Pd and Qm were 0.19 and 0.27, respectively. This can be intuitively understood considering that the seasonal variation of Qm is much larger than Pd. This distinctive difference of the $1^{st}$ harmonic value has been used to identify evergreen and deciduous forests. Overall agreement between the Fourier analysis-based map and the actal vegetation map has been estimated to be as high as 75%. This study found that the DFT analysis can be a concise and repeatable method to separate and trace the changes of evergreen and deciduous forest using the annual NDVI cycles.