• Bulletin of the Korean Chemical Society
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• 제20권8호
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• pp.910-916
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• 1999

A current interest in chemistry concerns traceability of analytical measurements to the International System of Units (SI) and the proper estimation of their uncertainties in accordance with the internationally agreed guide provided by the International Organization for Standardization (ISO). Isotope dilution mass spectrometry (IDMS) is regarded as a primary method, which make the measurement results traceable to SI units without significant empirical correction factors. Our laboratory, as the national standards institute of Korea, participated in an intercomparison of environmental analysis, pp'-DDE in corn oil, which was organized by the CCQM under supervision of the CIPM to test feasibility of IDMS as a primary method for the trace analysis of organic compounds. In this report, we provide basic equations used for the calculation of the concentration of the analyte in a sample and a precise description of the processes for the evaluation of the uncertainties of the measurement results. Also, we report the experimental conditions adopted to improve the accuracy of the IDMS measurement. The principles contained in ？？Guide to the Expression of Uncertainty in Measurement'' provided by ISO are followed for the uncertainty evaluation.

• Journal of Electrical Engineering and information Science
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• 제1권1호
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• pp.108-117
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• 1996

In this paper, we propose a new type of recurrent neural network architecture in which each output unit is connected with itself and fully-connected with other output units and all hidden units. The proposed recurrent network differs from Jordan's and Elman's recurrent networks in view of functions and architectures because it was originally extended from the multilayer feedforward neural network for improving the discrimination and generalization power. We also prove the convergence property of learning algorithm of the proposed recurrent neural network and analyze the performance of the proposed recurrent neural network by performing recognition experiments with the totally unconstrained handwritten numeral database of Concordia University of Canada. Experimental results confirmed that the proposed recurrent neural network improves the discrimination and generalization power in recognizing spatial patterns.

• 대한치과교정학회지
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• 제46권6호
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• pp.364-371
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• 2016

Objective: With the introduction of third-generation light-emitting diodes (LEDs) in dental practice, it is necessary to compare their bracket-bonding effects, safety, and efficacy with those of the second-generation units. Methods: In this study, 80 extracted human premolars were randomly divided into eight groups of 10 samples each. Metal or polycrystalline ceramic brackets were bonded on the teeth using second- or third-generation LED light-curing units (LCUs), according to the manufacturers' instructions. The shear bond strengths were measured using the universal testing machine, and the adhesive remnant index (ARI) was scored by assessing the residual resin on the surfaces of debonded teeth using a scanning electron microscope. In addition, curing times were also measured. Results: The shear bond strengths in all experimental groups were higher than the acceptable clinical shear bond strengths, regardless of the curing unit used. In both LED LCU groups, all ceramic bracket groups showed significantly higher shear bond strengths than did the metal bracket groups except the plasma emulation group which showed no significant difference. When comparing units within the same bracket type, no differences in shear bond strength were observed between the second- and third-generation unit groups. Additionally, no significant differences were observed among the groups for the ARI. Conclusions: The bracket-bonding effects and ARIs of second- and third-generation LED LCUs showed few differences, and most were without statistical significance; however, the curing time was shorter for the second-generation unit.

• 대한치과교정학회지
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• 제23권3호
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• pp.375-389
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• 1993

The delivery of optimal orthodontic treatment is greatly influenced by a clinician's ability to predict and control tooth movement achieved by applying known force systems to the dentition. It is important to determine the location of the center of resistance of a tooth or group of teeth to better understand the nature of their displacement characteristics under the various force levels. The purpose of this study was to define the location of the centers of resistance of various units of the upper anterior segment for lingually directed 100gm and 200gm force in a dry human skull. The units investigated were composed of four incisors and six anterior teeth. In addition, the effect of change in force magnitude on the location of the center of resistance of these units was investigated. The laser reflection technique was used to measure the initial displacements of the consolidated teeth under loading. The results were as follows: 1. The instantaneous center of resistance for the four anterior teeth was located vertically between level 4 and level 5-that is, at $37.4\%$ apical to the cementoenamel junction level. 2. The instantaneous center of resistance for the six anterior teeth was located vertically just beneath level 5-that is, at $50.3\%$ apical to the cementoenamel junction level. 3. Increasing force levels had little effect on the location of the center of resistance of a given unit. 4. The location of the instantaneous center of resistance shifted apically as the number of dental units consolidated increased.

• Asian-Australasian Journal of Animal Sciences
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• 제12권2호
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• pp.197-202
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• 1999

Three barrows weighing 45.0 kg, fitted with simple T-cannulas in both the duodenum and terminal ileum, were assigned to diets in a $3{\times}3$ Latin Square design experiment to determine the effect of two calcium levels (0.8% vs 0.4%) on phytase activity and nutrient balance in growing pigs. The control diet contained 0.8% calcium, with no added inorganic phosphorus (0.45% total phosphorus) and no added phytase. The two additional experimental diets contained microbial phytase (750 phytase units/kg) and supplied either 0.8% or 0.4% calcium. With added microbial phytase, ileal and total tract digestibility of rotal phosphorus were improved by 20.9 and 13.8 percentage units, respectively (p=0.01). The apparent duodenal and ileal digestibility of phytate phosphorus were increased by 51.8 and 49.7 percentage units (p=0.01). Lowering dietary calcium in the presence of microbial phytase increased the digestibility of phytate phosphorus by an additional 10.9 (p=0.001) and 5.7 percentage units for duodenal and ileal digestibility, respectively. Supplementation with microbial phytase significantly reduced fecal excretion of nitrogen and phosphorus and increased the percentage of these nutrients retained by the pig. Lowering dietary calcium further increased the percentage of dietary phosphorus retained. Overall, reducing dietary calcium appeared to increase the effectiveness of added microbial phytase in degrading phytate phosphorus. As a result, care should be taken to avoid high levels of dietary calcium when supplementing swine diets with microbial phytase.

• 한국작물학회지
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• 제26권4호
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• pp.293-297
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• 1981

맥류시험에 있어서 표본추출 체계를 확립하기 위하여 1979/80년 맥류연구소의 포장에서 실시한 몇가지 소맥재배양식에 대한 표본단위의 크기 및 주어진 정도를 위한 표본수 결정을 시도하였던 바 그 결과를 요약하면 다음과 같다. 1. 소맥의 수수에 대한 변이계수는 휴입광철파를 제외하고는 맥류수량의 평균변이계수와 거의 같았다. 2. 수수의 변이계수와 표본단위의 크기에 대한 회귀계수는 유입광철파를 제외하고 모두 1% 수준에서 유의성을 보였다. 3. 표본단위의 크기는 재배양식에 따라 차이가 크며 변이계수 15%를 허용한다면 협폭파, 관행 및 Drill 파는 각각 0.40, 0.17 및 0.11$m^2$, 로 추정되며 답리작의 유입광철파는 0.55$m^2$, 로 추정되었다. 4. 표본단위간 변이가 심하여 시험오차의 분산성분이 영인 조건하에서 CV=12%를 위해서 2반복인 경우는 구당 2개의 표본단위, 4반복민 경우는 구당 1개의 표본단위로 충분한 것으로 추정되었다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제12권1호
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• pp.27-40
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• 1990

In recent years, tissue antigens and enzymes that will serve as phenotypic markers for malignant cells are becoming increasingly important as diagnostic aids. This study was undertaken to investigate the specific activities of these enzymes in DMBA-induced rat submaxillary gland carcinogenesis. One hundred and twenty Sprague-Dawley rats about 100 gms of body weight were used. In experimental group, DMBA pellet (5mg) was implanted into right submaxillary gland and sham operation was performed into left gland to serve as control. The animals were sacrificed every three weeks up to 15 weeks. Submaxillary glands were excised on both sides and enzyme assays for ${\gamma}-glutamyl$ transpeptidase (GGT), 5'-Nucleotidase, Ornithine decarboxylase(ODC) and Acetyl-Co A carboxylase were carried out biochemically. The obtained results were as follows ; 1. In control group, there was no significant weight change of submaxillary gland, while experimental group, weight was increased remarkably about 7-fold at 15th week since DMBA implantation. 2. In control group, there was no change in specific activities of enzymes during the experimental period. 3. GGT activity was rapidly increased reaching a peak of 1.766${\pm}$0.082units/mg of DNA, 8-fold greater than that of onset. 4. 5'-Nucleotidase activity was increased reaching a peak of $362.1{\pm}53.2{\mu}moles/mg$ of DNA at 9th week. 5. ODC activity was rapidly increased, reaching a peak of 26.2${\pm}$4.8nmoles/mg of DNA at 9th week and quickly returned to that of control at 15th week. 6. Acetyl-Co A carboxylase activity was rapidly increased earlier than other enzymes, reaching a peak of 0.178${\pm}$0.013units/mg of DNA at 6th week and quickly declined to the control level at 15th week.

• Communications for Statistical Applications and Methods
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• 제24권3호
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• pp.241-254
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• 2017

Drawing a sample can be costly or time consuming in some studies. However, it may be possible to rank the sampling units according to some baseline auxiliary covariates, which are easily obtainable, and/or cost efficient. Ranked set sampling (RSS) is a method to achieve this goal. In this paper, we propose a modified approach of the RSS method to allocate units into an experimental study that compares L groups. Computer simulation estimates the empirical nominal values and the empirical power values for the test procedure of comparing L different groups using modified RSS based on the regression approach in analysis of covariance (ANCOVA) models. A comparison to simple random sampling (SRS) is made to demonstrate efficiency. The results indicate that the required sample sizes for a given precision are smaller under RSS than under SRS. The modified RSS protocol was applied to an experimental study. The experimental study was designed to obtain a better understanding of the pathways by which positive experiences (i.e., goal completion) contribute to higher levels of happiness, well-being, and life satisfaction. The use of the RSS method resulted in a cost reduction associated with smaller sample size without losing the precision of the analysis.

• Asian-Australasian Journal of Animal Sciences
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• 제16권6호
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• pp.873-879
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• 2003

The study was conducted to improve the nutritive value of defatted rice polishing (DRP). DRP was treated with various concentrations of HCl, NaOH, $H_2O_2$ and Kemzyme-H $F^{(R)} and the effect on its chemical composition and nutritive value in broiler chicks was observed. The treatments levels of 0.4 N HCl, 0.2 N NaOH and 6% $H_2O_2$ were selected from many concentrations of HCl, NaOH and $H_2O_2$ tried earlier on DRP. The selection was made on the basis of release of nutrients from DRP. The Kemzyme-H $F^{(R)} was used at rate of 0.1% of DRP. The selected concentrations of HCl, NaOH, and $H_2O_2$ were then used for treatment of DRP that was used in biological experiments. Two hundred and forty, day-old Hubbard male broiler chicks (38-40 g) were randomly divided into 48 experimental units with five chicks each. Each chemically treated DRP was incorporated into broiler diets at 10, 20 or 30% levels replacing yellow corn from the control feed and thus sixteen experimental feeds were prepared. These feeds were randomly assigned to 48 experimental units such that there were three replicates of chicks on each diet. The results of the study suggest that DRP can be effectively used in broiler diets at 20% level. The best weight gain and feed conversion ratio were observed with diet containing 20% level of DRP treated with 6% $H_2O_2$. The diets containing 30% levels of treated DRP were uneconomical, as excess use of oil was required to compensate the energy needs of the birds.

• Physical Therapy Rehabilitation Science
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• 제8권3호
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• pp.134-140
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• 2019

Objective: The purpose of this study was to investigate the effect of exercise therapy and bedside ergometer exercise on muscle strength, function level, and quality of life of persons in intensive care. Design: Randomized Controlled Trial Methods: Sixteen patients in the ICU were randomly assigned to either the exercise group (n=8) or the bedside cycle ergometer group (n=8). Activities in the ICU exercise group (rolling, sitting at the edge of the bed, transfer from sitting to standing, standing balance training, ambulation) and bedside cycle ergometer group were performed 5 times a week for 30 minutes during the ICU admission period. Medical Research Council (MRC) and Functional Status Scale-Intensive Care Unit (FSS-ICU) parameters were assessed at the time of admission to the ICU, and reevaluation was assessed on the day of ICU discharge. The Short Form-36 (SF-36) was assessed at the time of discharge from the ICU. Results: MRC and FSS-ICU were significantly increased before and after intervention in both the experimental and control groups (p<0.05). There was a significant difference between MRC and FSS-ICU in the comparison of the changes before and after the intervention (p<0.05). SF-36 was compared between groups after intervention and there was a significant difference between the experimental and the control group (p<0.05). Conclusions: Muscle strength and functional levels improved after intervention in both the experimental and control groups. The ICU exercise group was more effective than the bedside cycle ergometer group to improve muscle strength, functional level, and quality of life performance of persons in the ICU.