• Journal of the Korean Statistical Society
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• v.35 no.4
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• pp.355-376
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• 2006

To identify whether the sequence of observations follows a chain dependent process and whether the chain dependent or repeated observations follow stationary process or not, alternative procedures are suggested in this paper. These test procedures are formulated on the basis of logistic regression model under the likelihood ratio test criterion and applied to the daily rainfall occurrence data of Bangladesh for selected stations. These test procedures indicate that the daily rainfall occurrences follow a chain dependent process, and the different types of transition probabilities and overall transition probabilities of Markov chain for the occurrences of rainfall follow a stationary process in the Mymensingh and Rajshahi areas, and non-stationary process in the Chittagong, Faridpur and Satkhira areas.

• Archives of Pharmacal Research
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• v.18 no.5
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• pp.314-319
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• 1995

Antacid granules were prepared by agglomeration and powder method in high speed agitation type granulator. The copmositions of the test antacids were sodium bicarbonate nad magnesium carbonate nad a coating material was powder of polyvinylacetal diethyl-aminocacetate (AEA) and an additive material was talc powder. The dissolution characteristics of base from the antacid granules were investigated to evaluate neutralization capacity of hydrochloric profile of base and neutralization behavior, the following results were obtained : The prepared granules showed a pH-dependent dissolution pattern of a base. The dissolution profile of a base was varied with addition of talc powder as well as coating amount of AEA. The relationship between the ratio of dissolution retarded time for 20% and 10% AEA. The relationship between the ratio of dissolution retarded time for 20% AEA coated granules $\theta_{20}/\theta_{10}$ and the diameter reduction of the granules was explained by the rate process of neutralization of hydrochloric acid.

• Journal of the Korean Ceramic Society
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• v.33 no.7
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• pp.802-808
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• 1996

PbTiO3 thin films were fabricated onto MgO(100) single crystal substrate by reactive D. C magnetron sput-tering of Pb and Ti metal in an oxygen and argon gas mixture. The annealing of the thin films resulted in the decrease of both the c-axis orientation ratio and the lattice parameter. It is well known that the c-axis lattice parameter of thin film is dependent on the Pb/(Pb+Ti)ratio and the residual stress in the film The PbTiO3 thin films with a Pb/(Pb+T) ratio ranging from 0.45 to 0.57 were fabricated and annealed. The structure of the film the c-axis orientation ratio and the lattice parameter were not dependent on the Pb/(Pb+Ti) ratio before and after annealing. These experimental results proved that the decrease of the c-axis lattice parameter under the annealing conditions was due to the relaxation of the intrinsic stress in the film. This relaxation of the intrinsic stress caused the decrease of the c-axis orientation ratio and this phenomenon can be explained by c-axis growth lattice model.

• Journal of the Korea Institute of Military Science and Technology
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• v.16 no.1
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• pp.40-47
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• 2013

By virtue of Rec. ITU-R P.1546 and geography information system, interference analysis for the fixed wireless system and radar has been presented based upon the frequency-distance rules with minimum coupling loss, and a comprehensive methodology for assessing interoperability between systems was examined in terms of received signal, protection ratio, frequency dependent rejection. Also to find the antenna gain from a discrimination angle, a useful S-I plane was introduced based on signal and interference vectors derived from the real map with geographic information. To show some computational results, geography information on the map was taken for the given area, and field strength and path profile were illustrated for the radar and fixed wireless system operating at 2.7 GHz, for convenience. In addition the interference effect of receiver was also checked as a function of radar beam direction including protection ratio and frequency dependent rejection. The developed interference analysis can be actually applied to evaluate interoperability for wireless systems in the VHF and UHF bands.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.3
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• pp.548-554
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• 1994

The high temperature fatigue crack growth behavior of SUS 304 stainless steel at $550^{\circ}C$ and $650^{\circ}C$ was investigated under various kinds of stress ratio and frequency in sinusoidal waveform on the basis of the non-linear fracture mechanics. The result arranging crack growth rate by modified J-integral J' showed influence of stress ratio and frequency. All the data obtained under the test at $550^{\circ}C$ were plotted within data band of da/dN-${\triangle}J_f$ relationship for cycle-dependent crack growth. On the basis of static creep and cycle-dependent data band; both time- and cycle-dependent crack growth behavior was observed under loading conditions at $650^{\circ}C$, but cycle-dependent crack growth behavior predominantly appeared and time-dependent crack growth behaviour was little observed under loading conditions at $550^{\circ}C$. Fractographic examinations for fracture surface indicated that the fracture mode was generally transgranular. The stripes were found on fracture surface and each stripe was accompanied by a crack tip blunting and an abrupt increase in the load-point displacement. The $J'_{an}$ had a validity in case of $650^{\circ}C, but scarcely had it in case of $550^{\circ}C$.

• Journal of the Korea Safety Management & Science
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• v.9 no.3
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• pp.165-171
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• 2007

Dependent models in quality statistics are classified as serially autocorrelated model, multivariate model and dependent sample model. Dependent sample model is most efficient in time and cost to obtain samples among the above models. This paper proposes to implement parametric and nonparametric models into production system depended on demand pattern. Nonparametric models have distribution free and asymptotic distribution free techniques. Quality statistical models are classified into two categories ; the number of dependent sample and the type of data. The type of data consists of nominal, ordinal, interval and ratio data. The number of dependent sample divides into 2 samples and more than 3 samples.

• Journal of the Korean Society of Safety
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• v.30 no.1
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• pp.8-13
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• 2015

The experimental design methodology was applied in the drop tube furnace (DTF) to predict the various combustion properties according to the operating conditions and to assess the coal plant safety. Response surface method (RSM) was introduced as a design of experiment, and the database for RSM was set with the numerical simulation of DTF. The dependent variables such as burnout ratios (BOR) of coal and $CO/CO_2$ ratios were mathematically described as a function of three independent variables (coal particle size, carrier gas flow rate, wall temperature) being modeled by the use of the central composite design (CCD), and evaluated using a second-order polynomial multiple regression model. The prediction of BOR showed a high coefficient of determination (R2) value, thus ensuring a satisfactory adjustment of the second-order polynomial multiple regression model with the simulation data. However, $CO/CO_2$ ratio had a big difference between calculated values and predicted values using conventional RSM, which might be mainly due to the dependent variable increses or decrease very steeply, and hence the second order polynomial cannot follow the rates. To relax the increasing rate of dependent variable, $CO/CO_2$ ratio was taken as common logarithms and worked again with RSM. The application of logarithms in the transformation of dependent variables showed that the accuracy was highly enhanced and predicted the simulation data well.

• YAKHAK HOEJI
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• v.43 no.1
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• pp.85-90
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• 1999

FTY720, a novel immunosuppressant, elevated the level of endogenous sphingoid bases in a dose-dependent manner within 3 hr in $LLC-PK_1$ cells. The relative molar ratio of sphingoid bases expressed as sphingosine/sphinganine (SPN/SPA), a biomarker of altered sphingolipid biosynthesis, in $10{\;}{\mu}M$ of FTY720 showed tow-fold increase as compared with the one in control culture. FTY720 under the serum-free medium condition increased only cytosolic free sphingosine concentration, not sphinganine concentration in a time-dependent manner over the 8 hr incubation under the same condition as in serum free cultures, the SPN/SPA ratio began to fluctuate and the number of floating cells as an indicator of cytotoxicity was increased 8 hr after the addition of FTY720 to cultured cells. These results suggest that the process of FTY720-induced cell death in $LLC-PK_1$ cells.

• Journal of Nutrition and Health
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• v.35 no.5
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• pp.531-543
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• 2002

To assess the dietary therapy compliance of non-insulin-dependent diabetes mellitus (NIDDM) patients living in Daegu, we evaluated diet adequacy levels by index of nutritional quality (INQ), nutrient adequacy ratio (NAR), mean adequacy ratio (MAR), and dietary variety score (DVS) with food exchange system and Korean recommended dietary allowances (KRDA). One day dietary intake was measured by 24 hour recall method for 229 subjects over 20 years of age. Average daily energy intake was 1444 kcal. The relative ratio of carbohydrate, protein and fat in terms of energy intake was 69.4：14.5：16.0. The nutrient adequacy ratio (NAR) for Vitamin A, B$_2$, calcium were lower than 0.5 and MAR was 0.65. It appeared that the consumption of each food group as compared to prescribed food exchange unit was insufficient, in the order of dairy group (10.2 $\pm$ 25.2%), fruits group (58.2 $\pm$ 71.2%) and oils & fats group (42.9 $\pm$ 42.0%). The dietary variety score (DVS) was evaluated as an useful tool for diabetes' meal management when we accept minimum intake as 0.3 of food exchange unit. We found significant correlation between food groups and anthropometric indices: cereals group and % total body fat (r = 0.251, p < 0.01), meat group and waist circumference (r = 0.241, p < 0.01), vegetables group and WHR(r = 0.139, p < 0.05), and oils poop and WHR(r = 0.165, p < 0.05). from these results, we concluded that overall status of dietary intake of NIDDM patients in Daegu area was insufficient not only in quality but also in quantity. It is suggested that nutrition education for NIDDM patients should stress on balanced food consumption to meet proscribed amount by six food group to improve the inadequacy of dietary status.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.12C
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• pp.1175-1187
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• 2007

This paper proposes a novel crest factor reduction (CFR) algorithm to be deployed on WCDMA basestation. Generally speaking, it is well described that the reduction of peak-to-average ratio (PAR) yields the possibility of using low cost power amplifier such that the basesation becomes economic However, the simple reduction of PAR could degrade the signal quality measured by either peak code domain error (PCDE) or error vector measurement (EVM), and the level of channel interference constrained by adjacent channel leakage ratio (ACLR). Regarding these imperfections, this paper introduces an effective CFR algorithm in which the function of filter-dependent CFR (FDCFR) incorporated with the histogram-based waterfilling code domain compensation (HBWCDC) carries out. To verify the performance of the proposed CFR technique, substantial simulations including comparative works are conducted with obeying W-CDMA basestation verification specification. To exploit the superiority, the performance of the proposed method is tentatively compared with that associated to the simple memoryless clipping method and the memory-required filter-dependent clipping method.