• Title, Summary, Keyword: Two-step Method

Search Result 2,196, Processing Time 0.051 seconds

A Study on the analysis of physical assessment by school nurses (양호교사에 의한 학생(學生) 신체검사(身體檢査) 능력(能力)에 관한 평가(評價))

  • Kim, Hwa Joong
    • Journal of the Korean Society of School Health
    • /
    • v.1 no.1
    • /
    • pp.148-159
    • /
    • 1988
  • For the evaluation of physical assessment by school nurses, this study was designed in two steps physical assessment. The first step is the primary health screening by school health nurses. The second step is the Physicians' physical examination of ill health students selected by school nurses. This study was conducted on a total of 3,525 students of three primary schools located in urban, township, and rural area during the period from May to June, 1987, all data were collected through direct observation & survey method. The main findings are as follows 1. The number of ill health students selected by two step method was more than that of one step method by the physician. 2. The types of ill health students selected by two step method had more diversity than that of one step method by the physician. 3. Budgets and time consumption for two step method were more reductive than that of one step method by the physician.

  • PDF

Estimation of Spatial Dependence with GEE

  • Lee, Yoon-Dong;Choi, Hye-Mi
    • Proceedings of the Korean Statistical Society Conference
    • /
    • /
    • pp.269-273
    • /
    • 2003
  • We consider an efficient parametric estimation method of spatial dependence in weak stationary processes. Spatial dependence is modeled through variogram and correlogram. Most of parametric estimation methods of correlogram use two step method; nonparametric estimation and parametric integration. We bind these two steps into one step by using GEE method instead of least squares type optimization. Our one step method is more efficient statistically and gives a clear interpretation of related concepts used in traditional two step methods.

  • PDF

Flame-Retardant and Water-Repellent Finishing of Automobile Indoor Fabrics (자동차 내장용 직물의 난연 및 발수가공)

  • 박병기;이방원;김환철;김학용
    • Textile Coloration and Finishing
    • /
    • v.11 no.5
    • /
    • pp.7-12
    • /
    • 1999
  • The objective of this study is to apply water repellent and flame retardant finishes simultaneously to the fabric used for automobile. Both two step and one step methods were tried to apply the finishing agent to the fabric. In the two step method, water repellent agent was treated first, and flame retardant agent was applied next. The reverse finishing process was also attempted. In the one step method, flame retardant agent and water repellent agent treated to the fabric in one bath. The results of two step method revealed that the finishing effect was better when the water repellent agent was treated first than when flame retardant agent was treated first. In one step method, fluoro water repellent agent was superior to silicon water repellent agent.

  • PDF

Studies on the One Bath Two Step Dyeing of Wool/Cationized Cotton Blends with Acid Dye/Reactive Dye (양모/카티온화 면 혼방품의 산성염료/반응성염료에 의한 1욕2단 염색에 관한 연구)

  • 성우경;이춘길;권오경
    • Textile Coloration and Finishing
    • /
    • v.11 no.2
    • /
    • pp.46-54
    • /
    • 1999
  • The conventional dyeing of wool/cotton blends involves a two bath two step method, i.e., after dyeing of the wool component with acid dyes in an acidic dyebath at $100^\circ{C}$, the dyeing of the cotton component with reactive dyes in an alkaline dyebath is performed. In order to overcome the disadvantage of the conventional two bath two step dyeing method of wool/cotton blends, it had prompted significant effort to the development of the one bath dyeing method which can accomplish savings in time, energy and water usage. To improve dyeing property of wool/cotton blends, cotton component was pretreated with cationizing agent containing chlorohydrine group in aqueous solution of sodium hydroxide. This study was carried out to investigate dyeing possibilities of wool/cationized cotton blends with acid dye/reactive dye by one bath two step method.

  • PDF

On-the-fly Estimation Strategy for Uncertainty Propagation in Two-Step Monte Carlo Calculation for Residual Radiation Analysis

  • Han, Gi Young;Kim, Do Hyun;Shin, Chang Ho;Kim, Song Hyun;Seo, Bo Kyun;Sun, Gwang Min
    • Nuclear Engineering and Technology
    • /
    • v.48 no.3
    • /
    • pp.765-772
    • /
    • 2016
  • In analyzing residual radiation, researchers generally use a two-step Monte Carlo (MC) simulation. The first step (MC1) simulates neutron transport, and the second step (MC2) transports the decay photons emitted from the activated materials. In this process, the stochastic uncertainty estimated by the MC2 appears only as a final result, but it is underestimated because the stochastic error generated in MC1 cannot be directly included in MC2. Hence, estimating the true stochastic uncertainty requires quantifying the propagation degree of the stochastic error in MC1. The brute force technique is a straightforward method to estimate the true uncertainty. However, it is a costly method to obtain reliable results. Another method, called the adjoint-based method, can reduce the computational time needed to evaluate the true uncertainty; however, there are limitations. To address those limitations, we propose a new strategy to estimate uncertainty propagation without any additional calculations in two-step MC simulations. To verify the proposed method, we applied it to activation benchmark problems and compared the results with those of previous methods. The results show that the proposed method increases the applicability and user-friendliness preserving accuracy in quantifying uncertainty propagation. We expect that the proposed strategy will contribute to efficient and accurate two-step MC calculations.

Efficient two-step pattern matching method for off-line recognition of handwritten Hangul (필기체 한글의 오프라인 인식을 위한 효과적인 두 단계 패턴 정합 방법)

  • 박정선;이성환
    • Journal of the Korean Institute of Telematics and Electronics B
    • /
    • v.31B no.4
    • /
    • pp.1-8
    • /
    • 1994
  • In this paper, we propose an efficient two-step pattern matching method which promises shape distortion-tolerant recognition of handwritten of handwritten Hangul syllables. In the first step, nonlinear shape normalization is carried out to compensate for global shape distortions in handwritten characters, then a preliminary classification based on simple pattern matching is performed. In the next step, nonlinear pattern matching which achieves best matching between input and reference pattern is carried out to compensate for local shape distortions, then detailed classification which determines the final result of classification is performed. As the performance of recognition systems based on pattern matching methods is greatly effected by the quality of reference patterns. we construct reference patterns by combining the proposed nonlinear pattern matching method with a well-known averaging techniques. Experimental results reveal that recognition performance is greatly improved by the proposed two-step pattern matching method and the reference pattern construction scheme.

  • PDF

ON THE CONVERGENCE OF INEXACT TWO-STEP NEWTON-TYPE METHODS USING RECURRENT FUNCTIONS

  • Argyros, Ioannis K.;Hilou, Said
    • East Asian mathematical journal
    • /
    • v.27 no.3
    • /
    • pp.319-337
    • /
    • 2011
  • We approximate a locally unique solution of a nonlinear equation in a Banach space setting using an inexact two-step Newton-type method. It turn out that under our new idea of recurrent functions, our semilocal analysis provides tighter error bounds than before, and in many interesting cases, weaker sufficient convergence conditions. Applications including the solution of nonlinear Chandrasekhar-type integral equations appearing in radiative transfer and two point boundary value problems are also provided in this study.

A Simple Volume Tracking Method For Compressible Two-Phase Flow

  • SHYUE KEH-MING
    • Journal of The Korean Astronomical Society
    • /
    • v.34 no.4
    • /
    • pp.237-241
    • /
    • 2001
  • Our goal is to present a simple volume-of-fluid type interface-tracking algorithm to compressible two-phase flow in two space dimensions. The algorithm uses a uniform underlying Cartesian grid with some cells cut by the tracked interfaces into two subcells. A volume-moving procedure that consists of two basic steps: (1) the update of volume fractions in each grid cell at the end of the time step, and (2) the reconstruction of interfaces from discrete set of volume fractions, is employed to follow the dynamical behavior of the interface motion. As in the previous work with a surface-tracking procedure for general front tracking (LeVeque & Shyue 1995, 1996), a high resolution finite volume method is then applied on the resulting slightly nonuniform grid to update all the cell values, while the stability of the method is maintained by using a large time step wave propagation approach even in the presence of small cells and the use of a time step with respect to the uniform grid cells. A sample preliminary numerical result for an underwater explosion problem is shown to demonstrate the feasibility of the algorithm for practical problems.

  • PDF

A novel two sub-stepping implicit time integration algorithm for structural dynamics

  • Yasamani, K.;Mohammadzadeh, S.
    • Earthquakes and Structures
    • /
    • v.13 no.3
    • /
    • pp.279-288
    • /
    • 2017
  • Having the ability to keep on yielding stable solutions in problems involving high potential of instability, composite time integration methods have become very popular among scientists. These methods try to split a time step into multiple sub-steps so that each sub-step can be solved using different time integration methods with different behaviors. This paper proposes a new composite time integration in which a time step is divided into two sub-steps; the first sub-step is solved using the well-known Newmark method and the second sub-step is solved using Simpson's Rule of integration. An unconditional stability region is determined for the constant parameters to be chosen from. Also accuracy analysis is perform on the proposed method and proved that minor period elongation as well as a reasonable amount of numerical dissipation is produced in the responses obtained by the proposed method. Finally, in order to provide a practical assessment of the method, several benchmark problems are solved using the proposed method.

Application of Hyperbolic Two-fluids Equations to Reactor Safety Code

  • Hogon Lim;Lee, Unchul;Kim, Kyungdoo;Lee, Won-Jae
    • Nuclear Engineering and Technology
    • /
    • v.35 no.1
    • /
    • pp.45-54
    • /
    • 2003
  • A hyperbolic two-phase, two-fluid equation system developed in the previous work has been implemented in an existing nuclear safety analysis code, MARS. Although the implicit treatment of interfacial pressure force term introduced in momentum equation of the hyperbolic equation system is required to enhance the numerical stability, it is very difficult to implement in the code because it is not possible to maintain the existing numerical solution structure. As an alternative, two-step approach with stabilizer momentum equations has been selected. The results of a linear stability analysis by Von-Neumann method show the equivalent stability improvement with fully-implicit solution method. To illustrate the applicability, the new solution scheme has been implemented into the best-estimate thermal-hydraulic analysis code, MARS. This paper also includes the comparisons of the simulation results for the perturbation propagation and water faucet problems using both two-step method and the original solution scheme.