• Title/Summary/Keyword: p-p method

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Esophageal pH and Combined Impedance-pH Monitoring in Children

  • Shin, Myung Seok
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.17 no.1
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    • pp.13-22
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    • 2014
  • Esophageal pH monitoring is considered the gold standard for the diagnosis of gastroesophageal reflux disease because of the normal ranges across the pediatric age range. However, this method can only detect acid reflux. Multichannel intraluminal impedance-pH (MII-pH) monitoring has recently been used for the detection of bolus reflux in infants and children. This method allows for the detection of liquid, gas or mixed reflux in addition to acid, weakly acidic or weakly alkaline reflux. MII-pH monitoring can record the direction of flow and the height of reflux, which are useful parameters to identify an association between symptoms and reflux. However, the technique is limited by its high cost and the lack of normative data of MII-pH in the pediatric population. Despite certain limitations, MII-pH monitoring will become more common and gradually replace pH monitoring in the future, because pH monitoring is part of MII-pH.

Wind Speed Prediction using WAsP for Complex Terrain (복합지형에 대한 WAsP의 풍속 예측성 평가)

  • Yoon, Kwang-Yong;Yoo, Neung-Soo;Paek, In-Su
    • Journal of Industrial Technology
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    • v.28 no.B
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    • pp.199-207
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    • 2008
  • A linear wind prediction program, WAsP, was employed to predict wind speed at two different sites located in complex terrain in South Korea. The reference data obtained at locations more than 7 kilometers away from the prediction sites were used for prediction. The predictions from the linear model were compared with the measured data at the two prediction sites. Two compensation methods such as a self-prediction error method and a delta ruggedness index (RIX) method were used to improve the wind speed prediction from WAsP and showed a good possibility. The wind speed prediction errors reached within 3.5 % with the self prediction error method, and within 10% with the delta RIX method. The self prediction error method can be used as a compensation method to reduce the wind speed prediction error in WAsP.

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Wind Speed Prediction using WAsP for Complex Terrain (WAsP을 이용한 복잡지형의 풍속 예측 및 보정)

  • Yoon, Kwang-Yong;Paek, In-Su;Yoo, Neung-Soo
    • 한국신재생에너지학회:학술대회논문집
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    • 2008.10a
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    • pp.268-273
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    • 2008
  • A linear wind prediction program, WAsP, was employed to predict wind speed at two different sites located in complex terrain in South Korea. The reference data obtained at locations more than 7 kilometers away from the prediction sites were used for prediction. The predictions from the linear model were compared with the measured data at the two prediction sites. Two compensation methods such as a self-prediction error method and a delta ruggedness index (RIX) method were used to improve the wind speed prediction from WAsP and showed a good possibility. The wind speed prediction errors reached within 3.5 % with the self prediction error method, and within 10% with the delta RIX method. The self prediction error method can be used as a compensation method to reduce the wind speed prediction error in WAsP.

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Dynamic Economic Load Dispatch Problem Applying Valve-Point Balance and Swap Optimization Method (밸브지점 균형과 교환 최적화 방법을 적용한 동적경제급전문제)

  • Lee, Sang-Un
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.16 no.1
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    • pp.253-262
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    • 2016
  • This paper proposes a balance-swap method for the dynamic economic load dispatch problem. Based on the premise that all generators shall be operated at valve-points, the proposed algorithm initially sets the maximum generation power at $P_i{\leftarrow}P_i^{max}$. As for generator i with $_{max}c_i$, which is the maximum operating cost $c_i=\frac{F(P_i)-F(P_{iv_k})}{(P_i-P_{iv_k})}$ produced when the generation power of each generator is reduced to the valve-point $v_k$, the algorithm reduces i's generation power down to $P_{iv_k}$, the valve-point operating cost. When ${\Sigma}P_i-P_d$ > 0, it reduces the generation power of a generator with $_{max}c_i$ of $c_i=F(P_i)-F(P_i-1)$ to $P_i{\leftarrow}P_i-1$ so as to restore the equilibrium ${\Sigma}P_i=P_d$. The algorithm subsequently optimizes by employing an adult-step method in which power in the range of $_{min}\{_{max}(P_i-P_i^{min}),\;_{max}(P_i^{max}-P_i)\}$>${\alpha}{\geq}10$ is reduced by 10; a baby step method in which power in the range of 10>${\alpha}{\geq}1$ is reduced by 1; and a swap method for $_{max}[F(P_i)-F(P_i-{\alpha})]$>$_{min}[F(P_j+{\alpha})-F(P_j)]$, $i{\neq}j$ of $P_i=P_i{\pm}{\alpha}$, in which power is swapped to $P_i=P_i-{\alpha}$, $P_j=P_j+{\alpha}$. It finally executes minute swap process for ${\alpha}=\text{0.1, 0.01, 0.001, 0.0001}$. When applied to various experimental cases of the dynamic economic load dispatch problems, the proposed algorithm has proved to maximize economic benefits by significantly reducing the optimal operating cost of the extant Heuristic algorithm.

Development of Differential Diagnosis and Treatment Method of Reproductive Disorders Using Ultrasonography in Cows III. Differential Diagnosis between Developing and Regressing Corpus Luteum (초음파검사에 의한 소의 번식장애 감별진단 및 치료법 개발 III. 발육황체와 퇴행황체의 감별)

  • 손창호;강병규;최한선;임원호;강현구;오기석;신종봉;서국현
    • Journal of Veterinary Clinics
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    • v.16 no.1
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    • pp.118-127
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    • 1999
  • The aim of this study was to establish the method of differential diagnosis between developing and regressing corpus luteum in cows. Plasma progesterone (P$_4$) concentrations were determined by radioimmunoassay in slaughtered, cycling and pregnant cows. Ultrasonography was used to measure the corpus luteum size and histogram values for determining the correlationships between corpus luteum area or histogram values and plasma P$_4$ concentrations. The corpora lutea were monitored in vitro (water-bath scanning) by using ultrasonography with 7.5 MHz linear-array transducer in 196 slaughtered cows. The correlation coefficient between corpus luteum area and plasma P$_4$ concentrations was 0.46 (p<0.01), and between histogram values and plasma P$_4$ concentrations was -0.44 (p<0.01), respectively. The corpora lutea were monitored by ultrasonography with 5.0 MHz linear-array transrectal transducer in 188 cycling and 30 pregnant cows. The corpus luteum areas and plasma P4 concentrations were significantly different between regressing and other corpora lutea (p<0.01), and also histogram values were significantly different between regressing and developing corpola lutea (p<0.01). The correlation coefficients between corpus luteum areas and plasma P$_4$ concentrations were 0.76 (p<0.01), 0.71 (p<0.01), 0.65 (p<0.05) and 0.68 (p<0.05), and between histogram values and plasma P$_4$ concentrations were 0.74 (p<0.05), 0.71 (p<0.01), -0.52 (p<0.05) and 0.65 (p<0.05) in developing, functional, regressing and pregnant corpora lutea, respectively. These results indicate that corpus luteum areas and plasma P$_4$ concentrations were highly correlated in all stages of corpus luteum. The histogram values and plasma P$_4$ concentrations were positive correlated in developing, functional and pregnant corpora lutea, but negative correlated in regressing corpus luteum. Therefore, the measurement of corpus luteum area and histogram value by ultrasonography is reliable method for the assessment of luteal function, specially developing and regressing corpus luteum.

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A study on the effect of self-efficacy and stress-coping method of dental hygienist (치과위생사의 자기효능감이 스트레스 대처방식에 미치는 영향)

  • Won, Young-Soon;Park, So-Young;Kim, Jeong-Suk
    • Journal of Korean society of Dental Hygiene
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    • v.12 no.5
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    • pp.909-919
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    • 2012
  • Objectives : The purpose of this study was to examine the impact of the self-efficacy of dental hygienists on their stress-coping method. Methods : The subjects in this study were the dental hygienists in dental institutions that were selected by convenience sampling from Jeonju, Iksan, Gimjei and Gunsan in North Jeolla Province. A survey was conducted by using structured questionnaires. Results : A regression analysis was carried out to see whether self-efficacy would affect stress-coping method, and it's found that those whose overall self-efficacy was better made more use of an overall stress-coping method(p>0.001). General and social self-efficacy exerted a significant influence on a problem-oriented stress-coping method(p>0.001, p>0.01), and general and social self-efficacy had an impact on a stress-coping method of social support pursuit(p>0.01, p>0.01). In addition, general and social self-efficacy exercised an influence on a stress-coping method of wishful thinking(p>0.01, p>0.05). Conclusions : The self-efficacy of the dental hygienists affected their own stress-coping method, and the finding of the study suggests that a lot of efforts should be made from diverse angles to boost the self-efficacy of dental hygienists.

STUDY ON THE SPLITTING ALGORITHMSOF THE INCOMPRESSIBLE NAVIER-STOKES EQUATIONS USING P1P1/P2P1 FINITE ELEMENT FORMULATION (P2P1/P1P1 유한요소 공식을 이용한 비압축성 Navier-Stokes 방정식의 분리 해법에 대한 연구)

  • Cho Myung H.;Choi Hyoung G.;Yoo Jung Y.;Park Jae I.
    • 한국전산유체공학회:학술대회논문집
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    • 2005.10a
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    • pp.117-124
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    • 2005
  • Splitting algorithms of the incompressible Navier-Stokes equations using P1P1/P2P1 finite element formulation are newly proposed. P1P1 formulation allocates velocity and pressure at the same nodes, while P2P1 formulation allocates pressure only at the vertex nodes and velocity at both the vertex and mid nodes. For comparison of the elapsed time and accuracy of the two methods, they have been applied to the well-known benchmark problems. The three cases chosen are the two-dimensional steady and unsteady flows around a fixed cylinder, decaying vortex, and impinging slot jet. It is shown that the proposed P2P1 semi-splitting method performs better than the conventional P1P1 splitting method in terms of both accuracy and computation time.

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A Study on the Analysis of Accidents for Reinforced concrete Method and Pre-cast concrete Method (재래식 철근콘크리트 공법과 조립식 콘크리트 공법에서의 사고 분석에 관한 조사 연구)

  • Park, Jong-Keun
    • Journal of the Korean Society of Safety
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    • v.10 no.4
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    • pp.81-86
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    • 1995
  • In order to apply to analysis methods of mechanism and cross tabulation methods for the influence factors by the accident types to the object of accidents which occurred in R.C and P.C methods among the accidents in construction work sites, the latent hazards in P.C method are evaluated from the data of accidents in H Company from Jan. 1, 1993 to Dec. 31, 1993. The relationship between accident types and unsafe acts, unsafe conditions are recognized and the hazards of R.C method and P.C method are compared from the data acquired by the analysis of causes for a kind of occurrence mechanism. In conclusions, the items such as causes of accidents, accidents types, occurrence time, and the characteristics, are concentrated on one side in the P.C method, which is quite different from R.C method. Therefore the control method for the accident causes is easily established with a lot of effective advantages. The frequency and severity of accidents in P.C method are so low in comparison with R.C method.

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Changes in the Moisture Stability of $CaS:Eu^{2+}$ Phosphors with Surface Coating Methods

  • Yoo, Sun-Hwa;Kim, Chang-Keun
    • Macromolecular Research
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    • v.17 no.11
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    • pp.907-911
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    • 2009
  • To improve the moisture stability of the $CaS:Eu^{2+}$ red phosphor, surface coatings with silica nanoparticles were performed using five different methods, i.e., $P_1$, $P_2$, $P_3$, $P_4$, and $P_5$. The phosphors were coated with silica nanoparticles using a dip coating method ($P_1$) and sol-gel method ($P_2$). The phosphors were coated using a solution containing silica nanoparticles and poly(1-vinyl-2-pyrrolidone), PVP, $(P_3$). The phosphors were also coated with silica nanoparticles by reacting with the 1-vinyl-2-pyrrolidone (VP) monomer ($P_4$) or by reacting with mixtures containing VP and tetraethylorthosilicate ($P_5$). A decrease in the photoluminescence (PL) intensity was observed regardless of the coating methods. However, the moisture stability of the phosphors was enhanced by the coating when aged in a temperature-controlled humidity chamber. Among these methods, the $P_4$ (or $P_5$) method exhibited the greatest increase in moisture stability of the phosphors. The coated phosphors showed a relatively constant intensity with aging time, whereas the uncoated phosphor showed a decrease.

The Validity Analysis between Measurement Method of Subglottic Air Pressure (성문하압 측정방법의 타당도 분석)

  • Park, Sang-Hee;Jeong, Ok-Ran;Seok, Dong-Il
    • Speech Sciences
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    • v.8 no.3
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    • pp.201-208
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    • 2001
  • The purpose of the study was to examine a method most pertinent to measure subglottic air pressure. Subglottic air pressure and loudness analyses were performed on vowels /a/, /i/ and consonant /p/ in 12 normal subjects using. Aerophone II voice function. The experimental contexts were, therefore, /i:pi:pi:/ and /a:pa:pa:/. The subjects produced the intervocalic /p/ in 4 different situations: 1) /i:pi:pi:/ with voiceless /p/, 2) /i:pi:pi:/ with voiced /p/, 3) /a:pa:pa:/ with voiceless /p/, and 4) /a:pa:pa:/ with voiced /p/. A t-test and a correlation analysis revealed the following results. First, when we measured subglottic air pressure by /i:pi:pi:/, voiceless /p/ was significantly different from voiced /p/. Second, when we measured subglottic air pressure by /a:pa:pa:/, voiceless /p/ was significantly different from voiced /p/. Therefore, it was concluded that voiceless /p/ produced more accurate subglottic air pressure and clinicians needed to have patients produce accurate /p/ when measuring subglottic air pressure using Aerophone II.

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