• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.4
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• pp.442-450
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• 2008

In this paper, the phase diverisity in a direct-conversion receiver for a UHF RFID reader is analyzed and the optimal I/Q signal combining methods is presented with respect to tag modulation. At first, fading characteristics of a single channel receiver is shown to prove the importance of phase diversity due to the phase relationship between the backscattered signal and the local oscillator. And the optimal signal combining methods are presented in order to overcome the signal power reduction due to phase diversity. In case of ASK, the power combining method is presented for the optimal I/Q combining. And the arctangent and principal component combining methods using covariance matrix of I and Q channels are presented for the optimal I/Q combining in case of PSK. In order to analyze the performance of suggested methods, the selection diversity and the optimal combining methods are compared. According to analysis and simulation results, the optimal combining methods have a maximum 3 dB SNR enhancement than selection diversity.

• Communications for Statistical Applications and Methods
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• v.6 no.2
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• pp.645-658
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• 1999

One of the most popular graphical techniques for goodness of fit problems is the quantile-quantile plot(Q-Q plot) Easton and McCulloch(1990) suggested a way of generalizing Q-Q plots to multivariate cases bases on finding a matching between the points of the data set whose shape is being examined and a reference sample. in this paper we investigated the asymptotic behavior of the generalized Q-Q plot for bivariate cases. As a result we concluded that the standard univariate Q-Q plot and the generalized Q-Q plot have the same limit if two variables are independent.

• Korean Journal of Microbiology
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• v.42 no.3
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• pp.205-209
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• 2006

For measuring the viable cells in lakes, quantitative direct viable count (qDVC) method is applied. In the qDVC process, the final concentration of glycine is fixed as 2%. For confirming the effectiveness of qDVC for enumerating the viable cells, the viable bacterial numbers were measured by plate count, CTC reduction method and qDVC method at 5 different lakes. Among these 3 methods, the bacterial numbers by qDVC is $2.4{\sim}6.0$ times higher than those by the other 2 methods. And by the qDVC method, the viable cells were easily discriminated from dead or dormant cells.

• Journal of the Korean Institute of Intelligent Systems
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• v.13 no.6
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• pp.635-642
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• 2003

Reinforcement learning got successful results in a lot of applications such as control and scheduling. Various function approximation methods have been studied in order to improve the learning speed and to solve the shortage of storage in the standard reinforcement learning algorithm of Q-Learning. Most function approximation methods remove some special quality of reinforcement learning and need prior knowledge and preprocessing. Fuzzy Q-Learning needs preprocessing to define fuzzy variables and Local Weighted Regression uses training examples. In this paper, we propose a function approximation method, Fuzzy Q-Map that is based on on-line fuzzy clustering. Fuzzy Q-Map classifies a query state and predicts a suitable action according to the membership degree. We applied the Fuzzy Q-Map, CMAC and LWR to the mountain car problem. Fuzzy Q-Map reached the optimal prediction rate faster than CMAC and the lower prediction rate was seen than LWR that uses training example.

• Journal of applied mathematics & informatics
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• v.29 no.1_2
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• pp.39-48
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• 2011

Some existence theorems are obtained for periodic solutions of nonautonomous second-order differential systems with (q, p)-Laplacian by the minimax methods in critical point theory.

• Communications of the Korean Mathematical Society
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• v.35 no.3
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• pp.759-771
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• 2020

In this article, a hybrid class of the q-Hermite based Apostol type Frobenius-Genocchi polynomials is introduced by means of generating function and series representation. Several important formulas and recurrence relations for these polynomials are derived via different generating function methods. Furthermore, we consider some relationships for q-Hermite based Apostol type Frobenius-Genocchi polynomials of order α associated with q-Apostol Bernoulli polynomials, q-Apostol Euler polynomials and q-Apostol Genocchi polynomials.

• Journal of Digital Contents Society
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• v.10 no.2
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• pp.199-207
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• 2009

The Q-switching the shutter or the different optical science element puts in within the laser light resonator and the storehouse departs from the within the resonator it loses the mortar and the reversal distribution which when is sufficient creates from within the active medium, opens the shutter instantaneously and it is to do to be made to emit with the light where the energy which is accumulated within the resonator is strong very. Like this Q-switching of laser resonator--It decreases factor increasing suddenly to make. To method of Laser Q-switching mechanical switching methods, electro-optic switching methods and switching by saturable absorber methods, acousto-optic switching method etc. 4 kind are being used on a large scale. In these people the conversion which is electric in compliance with the effect which is electrooptics is widely being used the Q-switching pulse of short pulse width because being it will be able to create. Consequently, Pockel cell where it has the quality of electrooptics effect) the Q-it is become known that it is suitable it uses with switch. From the research which it sees FET and one-chip microprocessor where it is a switching element and pulse transfomer to plan and produce pockel cell Q-switch driving gears, pulse style Nd: It applied in YAG Laser system and it investigated and researched the operating characteristic of the Q-switch. Also, the Q-switch leads and Nd where it is output: YAG with forecast in compliance with a theoretical calculation it comes to buy laser beam side politics it compared and laser beam qualities which had become Q-switching it analyzed.

• Tunnel and Underground Space
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• v.18 no.6
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• pp.408-417
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• 2008

Rock mass classification methods such as RMR and Q system have different characteristics each other in parameters considered and applications, and so it is very important to prescribe the relationship between parameters for the analysis of correlativity of these methods. With the Held data of RMR and Q estimation in road construction sites, the acquaintance relations between RMR and Q of rock mass classifications are analyzed. The correlation equations between parameters of RMR and Q, matrix of correlation coefficients and the generalized form of acquaintance relation matrix are derived. This acquaintance relation matrix can be further extended to the form of generalized acquaintance relation network, and could be used to analyze the correlativity and to enhance the utility of common rock mass classification methods.

• The Korean Journal of Applied Statistics
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• v.34 no.3
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• pp.309-327
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• 2021

Dynamic treatment regimes (DTRs) are decision-making rules designed to provide personalized treatment to individuals in multi-stage randomized trials. Unlike classical methods, in which all individuals are prescribed the same type of treatment, DTRs prescribe patient-tailored treatments which take into account individual characteristics that may change over time. The Q-learning method, one of regression-based algorithms to figure out optimal treatment rules, becomes more popular as it can be easily implemented. However, the performance of the Q-learning algorithm heavily relies on the correct specification of the Q-function for response, especially in observational studies. In this article, we examine a number of double-robust weighted least-squares estimating methods for Q-learning in high-dimensional settings, where treatment models for propensity score and penalization for sparse estimation are also investigated. We further consider flexible ensemble machine learning methods for the treatment model to achieve double-robustness, so that optimal decision rule can be correctly estimated as long as at least one of the outcome model or treatment model is correct. Extensive simulation studies show that the proposed methods work well with practical sample sizes. The practical utility of the proposed methods is proven with real data example.

• Clinical and Experimental Reproductive Medicine
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• v.41 no.2
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• pp.68-74
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• 2014

Objective: In search of an ideal method of assisted hatching (AH), we compared the effects of conventional micropipette-AH and laser-AH on the blastocyst formation rate (BFR) and blastocyst cell numbers. Methods: Four-to five-week-old ICR female mice were paired with male mice after superovulation using Pregnant mare's serum gonadotropin (PMSG) and hCG. The two-cell embryos were flushed from the oviducts of female mice. The retrieved two-cell embryos underwent one of five AH procedures: single mechanical assisted hatching (sMAH); cross mechanical assisted hatching (cMAH); single laser assisted hatching (sLAH); quarter laser assisted hatching (qLAH); and quarter laser zona thinning assisted hatching (qLZT-AH). After 72 hours incubation, double immunofluorescence staining was performed. Results: Following a 72 hours incubation, a higher hatching BFR was observed in the control, sMAH, cMAH, and sLAH groups, compared to those in the qLAH and qLZT-AH groups (p<0.05). The hatched BFR was significantly higher in the qLAH and qLZT-AH groups than in the others (p<0.05 for each group). The inner cell mass (ICM) was higher in the control and sMAH group (p<0.05). The trophectoderm cell number was higher in the cMAH and qLAH groups (p<0.05). Conclusion: Our results showed that the hatched BFR was higher in groups exposed the the qLAH and qLZT-AH methods compared to groups exposed to other AH methods. In the qLAH group, although the total cell number was significantly higher than in controls, the ICM ratio was significantly lower in than controls.