• Journal of the Korean housing association
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• v.18 no.1
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• pp.83-93
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• 2007

Following the previous ones, this study is intended to explore methods of qualitative assessment on the view from apartment units. It first complemented and analyzed the attributes of landscape elements and then set up questionnaire items based on these attributes to identify the tendencies in apartment inhabitants' recognition of landscape elements, and then conducted a preference assessment on the test cases sampled on the basis of picture and other data collected in the previous studies to identify the characteristics of the preference for the view from apartment units according to landscape elements. Consequently, the following results have been derived. First, the landscape elements seen from apartment units may be classified into a total of sixteen categories, and the overall ratio of natural elements to artificial ones is shown to be approximately one to three. Second, it is also shown that apartment dwellers tend to prefer natural landscape elements over artificial ones, and the preferences for the distance to and location of landscape elements exhibit certain variance depending on the type of the elements. Third, the analysis of the preference for landscape elements has revealed that the types of landscape elements, the make-up and diversity of landscape elements, and the perceived distance to landscape elements as well as the resultant feeling of openness all affect the preference tendencies.

• Journal of Animal Science and Technology
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• v.45 no.5
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• pp.725-730
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• 2003

This study was conducted to evaluate the adequacy of an alternative a.m.-p.m. testing scheme for milk yield in comparison with the official test method based on weighing two milkings within 24 h. A total of 8,309 p.m. milking weights and 6,767 a.m. milking weights from 72 Holstein cows raised at N.L.R.I. were collected between October 2000 and November 2001. Ratios were computes for daily milk yield to a.m. and p.m. milking weights(direct yield ratios) and ratios of a.m. and p.m. milking weights to daily milk yield (inverse yield ratios). Analysis of variance indicated that the milking interval is the most important source of variation for yield ratios. Adjustment factors for estimating daily milk yield from single milking weights were derived through regression analysis of direct and inverse yield ratios on the length of the milking interval. Daily milk yield was estimated more precisely and accurately when adjustment factors were used than when single milking weights were doubled. In conclusion, alternative recording of a.m. and p.m. milking weights led to reliable estimates of milk yields.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.11 no.2
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• pp.169-174
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• 2018

In general, the methods of the analysis of variance(ANOVA) for the continuous data and the chi-square test for the discrete data are used for statistical analysis of the effect and the association. In multidimensional data, analysis of hierarchical structure is required and statistical linear model is adopted. The structure of the linear model requires the normality of the data. A multidimensional categorical data analysis methods are used for causal relations, interactions, and correlation analysis. In this paper, Bayesian network model using probability distribution is proposed to reduce analysis procedure and analyze interactions and causal relationships in categorical data analysis.

• Journal of Periodontal and Implant Science
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• v.53 no.5
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• pp.362-375
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• 2023

Purpose: The aim of this study was to investigate the relationships between gingival thickness (GT) and keratinized gingiva width (KGW), papilla height (PH), and crown ratio (CR) by employing transgingival probing and an intraoral scanner (IOS). Methods: This cross-sectional study examined 360 maxillary anterior teeth from 60 patients. GT was assessed using transgingival probing with an endodontic spreader. KGW, CR, and PH were measured using an IOS. One-way analysis of variance, the Student's t-test, and Spearman correlation coefficients were employed for statistical analysis. Results: Higher GT was significantly associated with thinner KGW in the central region (P=0.019). There was no statistically significant difference in GT between teeth (P=0.06). PH was lower in lateral teeth than in canines (P=0.047), with a PH of 2.99 mm in lateral teeth. The KGW was narrower in canines than in central teeth (P=0.007). A moderate correlation was observed between KGW and PH in the central region (P=0.01), while a weak negative correlation was found between KGW and CR (P=0.043). Conclusions: A moderate negative correlation was found between GT and KGW, as well as between PH and KGW in central teeth. In contrast, a weak negative correlation existed between CR and KGW. The PH (2.99 mm) was lower in lateral teeth than in canines. The traditional paradigm, which suggests a positive correlation between KGW and GT, was reevaluated by measuring KGW using an IOS.

• Korean Journal of Environmental Biology
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• v.18 no.4
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• pp.377-385
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• 2000

This study was carried out to investigate the ecotoxicological response on Gammarus sobaegensis Ueno with acid stress. Mean value of $LT_{50}$ (lethal time 50%) under pH 3 condition as acute ecotoxicity test was observed to be 0.271 ($\pm$0.146) day. And 0.812 ($\pm$0.377) day under pH 4, respectively. Mean value of $LT_{50}$ under pH 3 and 5 were 6.313 ($\pm$0.828), and 9.475 ($\pm$4.881) day, respectively. Variance in chronic ecotoxicity test pH (F ratio: 11.240, P< 0.0005) and times (F ratio: 2.916, P< 0.0005) as single factor were revealed to be the major factor for determining LT$_{50}$ with acid depression. The variation of secondary gill surface with acid stress to be certain that wrinkle phenomenon. Being weak tolerance of G. sobaegensis against the acid stress, it shows the possibility to be examined as an aquatic toxicity test organism.

• Physical Therapy Korea
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• v.20 no.4
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• pp.1-8
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• 2013

This study analyzes how different knee flexion angles affect the abdominal and pelvic muscle activity during supine bridging. Twenty healthy subjects participated in the study. We used surface electromyography (EMG) to measure how three different knee flexion angles ($100^{\circ}$, $70^{\circ}$, and $40^{\circ}$) affected the activity of the transverse abdominis/internal oblique (TrA/IO), external oblique (EO), biceps femoris (BF), rectus femoris (RF), and gluteus maximus (GM) muscles on the dominant side during supine bridging. The one-way repeated analysis of variance (ANOVA) was used to determine the statistical significance of TrA/IO, EO, BF, RF and GM muscle activity and the GM/BF activity ratio. For the TrA/IO, EO, BF, and GM muscles, supine bridging with different knee flexion angles resulted in significant differences in abdominal and pelvic muscle activity. For the TrA/IO muscles, the post-hoc test demonstrated that muscle activity significantly increased at $40^{\circ}$ compared to $70^{\circ}$; however, there were no significant differences between $100^{\circ}$ and $70^{\circ}$ or $100^{\circ}$ and $40^{\circ}$. For the EO muscle, the post-hoc test demonstrated that muscle activity significantly increased at $40^{\circ}$ compared to $100^{\circ}$ and $70^{\circ}$; no significant difference was observed between angles $100^{\circ}$ and $70^{\circ}$. For the BF muscle, the post-hoc test demonstrated that muscle activity significantly increased according to the knee flexion angle ($40^{\circ}$ > $70^{\circ}$ > $100^{\circ}$). For the GM muscle, the post-hoc test demonstrated that muscle activity significantly increased according to the knee flexion angle ($100^{\circ}$ > $70^{\circ}$ > $40^{\circ}$). However, for the RF muscle, there was no significant difference. Additionally, the GM/BF activity ratio significantly increased according to the knee flexion angle ($100^{\circ}$ > $70^{\circ}$ > $40^{\circ}$). From these results, we can conclude that bridging with a knee flexion of $100^{\circ}$ can strengthen the GM muscle, whereas bridging with a knee flexion of $40^{\circ}$ is recommended to strengthen the IO, EO, and BF muscles. We can also conclude that knee flexion angles should be modified during supine bridging to increase the muscle activity of different target muscles.

• Journal of Pharmaceutical Investigation
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• v.38 no.4
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• pp.277-282
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• 2008

The purpose of the present study was to evaluate the bioequivalence of two topiramate tablets, Topamax tablet (Janssen Korea. Co., Ltd., Seoul, Korea, reference drug) and Topamin tablet (Myungmoon Pharm. Co., Ltd., Seoul, Korea, test drug), according to the guidelines of Korea Food and Drug Administration (KFDA). Twenty-four healthy male Korean volunteers received one tablet at the dose of 100 mg topiramate in a $2{\times}2$ crossover study. There were two-weeks washout period between the doses. Plasma concentrations of topiramate were monitored by an LC-MS/MS for over a period of 96 hr after administration. $AUC_t$ (the area under the plasma concentration-time curve from time zero to 96 hr) was calculated by the linear trapezoidal rule method. $C_{max}$ (maximum plasma drug concentration) and $T_{max}$ (time to reach $C_{max}$) were compiled from the plasma concentration-time data. Analysis of variance (ANOVA) was carried out using logarithmically transformed $AUC_t$ and $C_{max}$. The 90% confidence intervals of the $AUC_t$, ratio and the $C_{max}$ ratio for Topamin/Topamax were $\log0.88{\sim}\log1.02$ and $\log0.87{\sim}\log1.03$, respectively. These values were within the acceptable bioequivalence intervals of $\log0.80{\sim}\log1.25$. Taken together, our study demonstrated the bioequivalence of Topamax and Topamin with respect to the rate and extent of absorption.

• Restorative Dentistry and Endodontics
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• v.38 no.1
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• pp.21-25
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• 2013

Objectives: The aim of this study was to evaluate the shaping ability of newly marketed single-file instruments, Wave One (Dentsply-Maillefer) and Reciproc (VDW GmbH), in terms of maintaining the original root canal configuration and curvature, with or without a glide-path. Materials and Methods: According to the instruments used, the blocks were divided into 4 groups (n = 10): Group 1, no glide-path / Wave One; Group 2, no glide-path / Reciproc; Group 3, #15 K-file / Wave One; Group 4, #15 K-file / Reciproc. Pre- and post-instrumented images were scanned and the canal deviation was assessed. The cyclic fatigue stress was loaded to examine the cross-sectional shape of the fractured surface. The broken fragments were evaluated under the scanning electron microscope (SEM) for topographic features of the cross-section. Statistically analysis of the data was performed using one-way analysis of variance followed by Tukey's test (${\alpha}$ = 0.05). Results: The ability of instruments to remain centered in prepared canals at 1 and 2 mm levels was significantly lower in Group 1 (p < 0.05). The centering ratio at 3, 5, and 7 mm level were not significantly different. Conclusions: The Wave One file should be used following establishment of a glide-path larger than #15.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.4 no.3
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• pp.428-451
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• 2010

Traffic matrix-based anomaly detection and DDoS attacks detection in networks are research focus in the network security and traffic measurement community. In this paper, firstly, a new type of unidirectional flow called IF flow is proposed. Merits and features of IF flows are analyzed in detail and then two efficient methods are introduced in our DDoS attacks detection and evaluation scheme. The first method uses residual variance ratio to detect DDoS attacks after Recursive Least Square (RLS) filter is applied to predict IF flows. The second method uses generalized likelihood ratio (GLR) statistical test to detect DDoS attacks after a Kalman filter is applied to estimate IF flows. Based on the two complementary methods, an evaluation formula is proposed to assess the seriousness of current DDoS attacks on router ports. Furthermore, the sensitivity of three types of traffic (IF flow, input link and output link) to DDoS attacks is analyzed and compared. Experiments show that IF flow has more power to expose anomaly than the other two types of traffic. Finally, two proposed methods are compared in terms of detection rate, processing speed, etc., and also compared in detail with Principal Component Analysis (PCA) and Cumulative Sum (CUSUM) methods. The results demonstrate that adaptive filter methods have higher detection rate, lower false alarm rate and smaller detection lag time.

• Korean Journal of Applied Biomechanics
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• v.23 no.3
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• pp.253-259
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• 2013

The purpose of this study is to evaluate the influence of posture elements on symmetrical weight bearing during STS (sit-to-stand) in patients with chronic stroke. The subjects were patients diagnosed with stroke: a total of 24 patients (16 males and 8 females) participated in this study. All the participants performed STS tasks(3 foot postures and 2 arm postures). Two force plates (AMTI) were used to measure the peak vertical ground reaction force(Peak Fz) and the symmetrical ratio to peak vertical ground reaction force. The data were analyzed using independent t-test and 2-way repeated analysis of variance. The results of this study were as follows: 1) The peak Fz placed more weight on the paretic leg during STS and 2) The symmetrical ratio to the peak Fz showed a significant difference according to the foot and arm posture (p<.05), and had the highest AYM_GA ($0.87{\pm}0.12$). These results indicate that arm and leg postures during STS in patients with chronic stroke had the highest AYM_GA. We believe that the outcome of this study will be a reference for the prognosis of STS in patients with stroke.