• Journal of the Korean Society of School Health
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• v.1 no.1
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• pp.148-159
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• 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.

• Proceedings of the Korean Statistical Society Conference
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• 2003.05a
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• pp.269-273
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• 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.

• Textile Coloration and Finishing
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• v.11 no.5
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• pp.7-12
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• 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.

• Textile Coloration and Finishing
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• v.11 no.2
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• pp.46-54
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• 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.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.12
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• pp.2047-2054
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• 2003

In this paper, an approach of automatically finding and modifying the most appropriate orthogonal array (GO) is suggested and applied to a new structural optimization procedure with two steps. GO is motivated by the situation where finding a proper orthogonal array from the tables in the literature is difficult or impossible. Now the Taguchi method is made available for various numbers of variables and levels. In the two-step structural optimization, the Taguchi method equipped with GO and a shape optimization using the finite differencing method is consecutively applied. The existence or non-existence of an element can be taken as a factor level and this feature is utilized finding the best topology from a set of potential topologies suggested from the user's expertise. This greatly enhances applicability and one can expect a better result than the case in which each step is applied independently because these steps are complementary each other.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.31B no.4
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• pp.1-8
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• 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.

• Journal of The Korean Astronomical Society
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• v.34 no.4
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• pp.237-241
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• 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.

• Nuclear Engineering and Technology
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• v.35 no.1
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• pp.45-54
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• 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.

• Earthquakes and Structures
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• v.13 no.3
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• pp.279-288
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• 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.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.7
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• pp.793-796
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• 2004

In order to improve c-axis crystalline orientation and high perpendicular coercivity of deposited ${Co}_77{Cr}_20{Ta}_3$perpendicualr recording layer, Two step method was investigated using a Facing Targets Sputtering System(FTS). The ${\Delta\theta}_50$ of ${Co}_77{Cr}_20{Ta}_3$recording layer deposited on seedlayer prepared at Room Temperature was as low as $5^\circ$, while that of the recording layer without seedlayer was about 11$^{\circ}$. The Two-Step method using ${Co}_77{Cr}_20{Ta}_3$seedlayer prepared at Room Temperature was shown to be very effective in controling the c-axis orientation of ${Co}_77{Cr}_20{Ta}_3$ recording layer with thin thickness.