• Communications for Statistical Applications and Methods
• /
• 제6권1호
• /
• pp.151-158
• /
• 1999

Distribution-free tests are proposed for AB/BA 2*2 cross-over design data based on placements introduced by Orban and Wolfe(1992). In this paper we suggest the homogeneity test or carry-over effects and also suggest the test for direct effects and the test for period effects under the same carry-over effects. The properties such as iterative asymptotic distribution for the proposed tests are discussed.

• EDISON SW 활용 경진대회 논문집
• /
• 제5회(2016년)
• /
• pp.37-54
• /
• 2016

The methods for estimating the change of free energy in dissipative particle dynamics (DPD) are discussed on the basis of fluctuation theorems. Fluctuation theorems are tactics to evaluate free energy changes from non-equilibrium work distributions and have several forms, as proposed by Jarzynski, Crooks, and Bennett. The validity of these methods however, has been shown merely with the molecular dynamics or Langevin dynamics. In this study, the appropriate forms of fluctuation theorems for dissipative particle dynamics, which has similar structure to that of Langevin dynamics, are suggested using Liouville's theorem, and they are proved equivalent to original fluctuation theorems. Work distribution functions, which are probability distribution functions of works exerted on the system within the systematic change, are the basics of fluctuation theorems and their shapes are turned out to be dependent on the phase space trajectory of the change of the system. The reliability of Jarzynski and Crooks methods is highly dependent on the number of simulations to measure works and the shapes of the work distribution functions. Bennett method, however, can evaluate free energy changes even when Jarzynski and Crooks methods fail to do so.

• 상하수도학회지
• /
• 제28권1호
• /
• pp.91-101
• /
• 2014

Three water treatment plants(WTPs) in Jeju island whose source water have different characteristics from those of the mainland of Korea were investigated. Coefficients of bulk water decay($k_b$) of free chlorine at $5^{\circ}C$ for ES, GJ, NW WTPs were $-0.003hr^{-1}$, $-0.002hr^{-1}$ and $-0.001hr^{-1}$ respectively based on bottle tests. To simulate the free chlorine variations in the distribution system using EPANET, ES WTP was chosen. Free chlorine concentrations of several sites were less than the drinking water quality standards(i.e., 0.1 mg/L); E5(0.03 mg/L), E6(0.02 mg/L), W21(0.02 mg/L) and W25(0.03 mg/L). To maintain more than 0.1 mg/L of free chlorine in the distribution system, at least 1.9 mg/L of chlorine was needed at the WTP, which suggested rechlorination was needed to supply palatable tap water to customers. Two sites, one that diverged into E5 and E6 in the east-line and another located before E21 in the west-line were selected for the appropriate rechlorination locations. The recommended rechlorination dosages were 0.42 mg/L for the east and 0.27 mg/L for the west. The simulated results indicated that the free chlorine could be reduced to 0.4 mg/L at the WTP with rechlorination, and taps with excessive free chlorine could be more stabilized(i.e., 0.1~0.4 mg/L).

• International Journal of Naval Architecture and Ocean Engineering
• /
• 제11권1호
• /
• pp.70-81
• /
• 2019

An improved three dimensional Rankine source method is developed to solve numerically water wave problems in time domain. The free surface and body surface are both represented by continuous panels rather than a discretization by isolated points. The integral of Rankine source 1/r on free surface panel is calculated analytically instead of numerical approximation. Due to the exact algorithm of Rankine source integral applied on the free surface and body surface, a space increment free surface source distribution method is developed and much smaller amount of source panels are required to cover the fluid domain surface than other numerical approximation methods. The proposed method shows a higher accuracy and efficiency compared to other numerical methods for various water wave problems.

• 전자통신동향분석
• /
• 제33권6호
• /
• pp.94-106
• /
• 2018

A quantum key distribution (QKD) provides in principle an unconditional secure communication unlike the standard public key cryptography depending on the computational complexity. In particular, free-space QKD can give a secure solution even without a fiber-based infrastructure. In this paper, we investigate an overview of recent research trends in the free-space QKD system, including satellite and handheld moving platforms. In addition, we show the key components for a free-space QKD system such as the integrated components, single photon detectors, and quantum random number generator. We discuss the technical challenges and progress toward a future free- space QKD system and components.

• 유통과학연구
• /
• 제16권11호
• /
• pp.37-45
• /
• 2018

Purpose - Recently, large quantities of factors have affected the signing of the Free Trade Agreement between two countries. Due to this background, this paper selects South Korea as an example to explore the determinants of Free Trade Agreement from Asian countries. Research design, data, and methodology - A cross sectional data of 2016 will be employed and some variables such as real income and GDP will be used to run an empirical analysis under the linear probability model, probit model and logit model. Results - The findings show that the Asian countries' exchange rate regime, real income, GDP and so forth can increase the probability of signing the Free Trade Agreement with Asian countries. Conversely, the distance can lower the probability of signing the Free Trade Agreement with Asian countries. Meanwhile, although the Asian countries' import, consumer price index and population also can affect the probability of signing the Free Trade Agreement with Asian countries, the estimated coefficients are not statistically significant at 5% level. Conclusions - According to the empirical results, this paper provides a new scope for South Korea's government to sign the Free Trade Agreement with other Asian countries.

• 대한수의학회지
• /
• 제13권1호
• /
• pp.17-21
• /
• 1973

Free amino acid extracts of musculus brachiocephalicus and musculus glutaeus of cattle, swine, goats and rabbits are analyzed to see the composition and the contents of free amino acids by thin layer chromatography and automatic amino acid analyzer. The results obtained are summarized as follows: 1. Meats of cattle, swine, goats and rabbits analyzed by thin layer chromatography have 6 kinds of free amino acids such as glycine, histidine, methionine, lysine, alanine and leucine, and the spots of glycine in chromatogram of meats of cattle, swine and goats and the ones of methionine in chromatogram of meats of rabbits are the largest and the most denes of all other ones. 2. Distribution curves of free amino acids in meats of cattle, swine, goats and rabbits showed significant differences, but differences on distribution curves of free amino acids between musculus-brachiocephalicus and musculus glutaeus of the same tested animal are not significant. 3. Contents of free amino acids in meats of cattle, swine, goats and rabbits showed significant differences, but differences on contents of free amino acids between musculus brachiocephalicus and musculus glutaeus of the same tested animal are not significant.

• Animal cells and systems
• /
• 제5권2호
• /
• pp.117-126
• /
• 2001

Occurence, seasonal changes and vertical distribution of the silica-scaled chrysophytes in a small fish-free pond were studied using electron microscopy (EM) and light microscopy (LM) from October 1998 to July 1999. The phytoplankton community was characterized by Chrysophyta and Cryptophyta. Ten species of the silica-scaled chrysophytes of genera Mallomonas, Synura, Chrysosphaerella and Spiniferomonas were identified by EM, and the most abundant species were Mallomonas akrokomos and M. portae-ferreae. The maximum population density of M. akrokomos was observed in December and several peaks appeared periodically at about one to two month intervals, whereas M. portae-ferreae developed the maximum density in March. The diurnal vertical distribution of M. akrokomos exhibited clear downward migration at night and slightly upward migration in the morning. A complex interaction among physico-chemical and biological factors seemed to affect the vertical distribution of M. akrokomos. However, the seasonal changes of M. akrokomos did not show significant corre1ations with the physico-chemical and some biologica1 factors. Although M. akrokomos was evenly distributed throughout the water column during some experimental periods, the diurnal patterns found in the two diurnal cycles showed consistency in that it clearly avoided the surface water during the day. This suggested that M. akrokomos may be a shade plankton with maximum densities below surface layer.

• Structural Engineering and Mechanics
• /
• 제88권6호
• /
• pp.551-567
• /
• 2023

In this work, the free vibration analysis of functionally graded material (FGM) sandwich plates with porosity is conducted using the p-version of the finite element method (FEM), which is based on the first-order shear deformation theory (FSDT). The sandwich plate consists of two face-sheet layers of FGM and a homogeneous core layer. The obtained results are validated using convergence and comparison studies with previously published results. Five porosities distribution models of FGM sandwich plates are assumed and analyzed. The effect of the thickness ratio, boundary conditions, volume fraction exponents, and porosity coefficients of the top and bottom layers of FGM sandwich plates on the natural frequency are addressed.

• 유통과학연구
• /
• 제16권8호
• /
• pp.39-50
• /
• 2018

Purpose - The ultimate purpose of this research is to analyze the influence of personal disposition on shopping value and behavioral intention by expanding the theory of planned behavior (TPB). Research design, data, and methodology - An attempt was made to examine the effects of personal disposition (reflecting duty-free shop characteristics) on three selective actions of consumers - compulsive buying, variety seeking, and price sensitivity. We conducted a questionnaire survey with the users of airport duty-free shops, downtown duty-free shops (offline), and online duty-free shops. In total, 410 copies of the questionnaire were analyzed using a structural equation model. Results - According to the results, compulsive buying, variety seeking, and price sensitivity significantly affected shopping value. Shopping value and subjective norms both had significant effects on attitude, the major variable in the TPB, and attitude had the greatest effect on behavioral intention, followed by subjective norms and perceived behavioral control in descending order. Conclusions - This study has academic implications in that it extends the existing theories of planned behavior and applies it to consumer characteristics and shopping value. It has practical implications as well in that it provides basic data that can be used to establish concrete marketing strategies for duty-free shop owners targeting segmented markets by closely examining customer desires.